Sample records for ammonium sulfates

  1. Ammonium sulfate preparation from phosphogypsum waste

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    Abdel-Hakim T. Kandil


    Full Text Available The Egyptian phosphogypsum waste is treated using sulfuric acid prior the ammonium sulfate production. The relevant factors that would affect the removal efficiencies of some impurities are studied. The optimum conditions of the treatment are 8 M sulfuric acid solution and 1/4 solid/liquid ratio for 30 min contact time at 80 °C. Moreover, the optimum conditions of the ammonium sulfate preparation are 10 g of the suspended impure or purified phosphogypsum in 40 ml of 3% ammonium sulfate solution (as initiator, 1/4 solid/liquid ratio at pH7 at an addition of an excess ammonium carbonate, and 150 rpm stirring speed for 4.0 h contact time at 55 °C as well as the 5 mg of barium chloride is added to remove the radium in the ammonium sulfate product. Finally, the ammonium sulfate is crystallized and the chemical analysis of the product shows 20% nitrogen and 23.6% sulfur. Therefore, the purity of the obtained ammonium sulfate is 95% from the purified phosphogypsum.

  2. On the evaporation of ammonium sulfate solution

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


    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.

  3. Performance of sulfate-dependent anaerobic ammonium oxidation

    Institute of Scientific and Technical Information of China (English)


    The performance of sulfate-dependent anaerobic ammonium oxidation was studied.The results showed that both SO42-and NH4+ were chemically stable under anaerobic conditions.They did not react with each other in the absence of biological catalyst(sludge).The anaerobic digested sludge cultivated in an anaerobic reactor for three years took on the ability of oxidizing ammonium with sulfate anaero-bically.The average reduction of sulfate and ammonium was 71.67 mg.L-1 and 56.82 mg.L-1 at high concentrations.The reaction between SO42-and NH4+ was difficult,though feasible,due to its low standard Gibbs free energy change.The experiment demonstrated that high substrate concentrations and low oxidation-reduction potential(ORP) may be favourable for the biological reaction.

  4. Performance of sulfate-dependent anaerobic ammo-nium oxidation

    Institute of Scientific and Technical Information of China (English)

    ZHANG Lei; ZHENG Ping; HE YuHui; JIN RenCun


    The performance of sulfate-dependent anaerobic ammonium oxidation was studied. The results showed that both SO42- and NH4+ were chemically stable under anaerobic conditions. They did not react with each other in the absence of biological catalyst (sludge). The anaerobic digested sludge cultivated in an anaerobic reactor for three years took on the ability of oxidizing ammonium with sulfate anaero-bically. The average reduction of sulfate and ammonium was 71.67 mg.L-1 and 56.82 mg.L-1 at high concentrations.The reaction between SO42- and NH4+ was difficult, though feasible, due to its low standard Gibbs free energy change. The experiment demonstrated that high substrate concentrations and low oxidation-reduction potential (ORP) may be favourable for the biological reaction.

  5. Sources et marché du sulfate d'ammonium Sources of and Market for Ammonium Sulfate

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    Loussouarn C.


    Full Text Available Engrais azoté le plus utilisé dans le monde jusqu'en 1970, le sulfate d'ammonium ne représente plus aujourd'hui que 4 % de la fertilisation azotée. Avec une teneur en azote de 21 % seulement, il a été peu à peu remplacé comme engrais universel par des produits plus concentrés, notamment l'urée et le nitrate d'ammonium. Obtenu pour plus de 40 % comme sous-produit dans la synthèse de monomères comme le caprolactame, l'acrylonitrile ou le méthacrylate de méthyle, et pour près de 10 % dans le traitement des gaz de cokerie, sa production dépend largement des développements du marché des fibres synthétiques, et, dans une moindre mesure, de la sidérurgie et de la métallurgie. Dans les pays développés, où la production est essentiellement fatale, le volume du marché est et sera plus fonction de la disponibilité du sulfate d'ammonium que de la demande ou de facteurs de marché; sa consommation ne résidera plus que dans des applications spécifiques pour lesquelles il sera bien adapté. Par contre, l'intérêt croissant pour compenser le déficit en soufre de certains sols, et les qualités agronomiques propres du sulfate d'ammonium laissent entrevoir la possibilité d'un essor de son utilisation dans certaines régions en voie de développernent. Ammonium sulfate was the most worldwide nitrogenous fertilizer used up to 1970. Today, it makes up only 4% of nitrogenous fertilization. With a nitrogen content of only 21%, it has gradually been replaced as a universal fertilizer by more concentrated products, particularly urea and ammonium nitrate. More than 40% of the ammonium sulfate is obtained as a by-product from the synthesis of monomers such as caprolactam, acrylonitrile or methyl methacrylate, and nearly 10% from coking gas processing. Its production depends extensively on the development of the market for synthetic fibers and, to a lesser extent, on the steel and metallurgical industries. In the industrialized countries

  6. Evidence for surface nucleation: efflorescence of ammonium sulfate and coated ammonium sulfate aerosol particles (United States)

    Ciobanu, V. Gabriela; Marcolli, Claudia; Krieger, Ulrich K.; Zuend, Andreas; Peter, Thomas


    Aerosol particles are ubiquitous in the atmosphere and can undergo different phase transitions, such as deliquescence and efflorescence. Using optical microscopy, we investigated the efflorescence of ammonium sulfate (AS) in supersaturated AS and 1:1 and 8:1 (by weight) poly(ethylene glycol)-400 (PEG-400)/AS particles, which were deposited as droplets with diameters in the 16 - 35 μm range on a hydrophobically coated slide. The PEG-400/AS particles that are exposed to decreasing relative humidity (RH) exhibit a liquid-liquid phase separation below 90 % RH with the PEG-400 phase surrounding the aqueous AS inner phase (Marcolli and Krieger, 2006; Ciobanu et al., 2009). Pure AS particles effloresced in the RH range from 36.3 to 43.7 % RH, in agreement with literature data (31 - 48 % RH). In contrast, 1:1 PEG-400/AS particles with diameters of the AS phase from 7.2 - 19.2 μm effloresced between 26.8 - 33.9 % RH and 8:1 PEG-400/AS particles with diameters of the AS phase from 1.8 - 7.3 μm between 24.3 - 29.3 % RH. Such low efflorescence relative humidity (ERH) values have never been reached before for AS particles of this size range. We show that neither a potential inhibition of water evaporation via anomalously slow diffusion through the PEG coating, nor the presence of low amounts of PEG-400 in the AS phase, nor different timescales between various experimental techniques could possibly explain the low AS ERH values of PEG-400/AS particles in our setup. High-speed photography of the efflorescence process allowed to monitor the proceeding of the AS crystallization fronts within the particles with millisecond time resolution. The nucleation locations were deduced based on the initial crystals growth locations. Statistical analysis of 31 and 19 efflorescence events for pure AS and 1:1 PEG-400/AS particles, respectively, identified the air/droplet/substrate contact line and the air/droplet interface as preferred nucleation locations in the case of pure AS particles

  7. Kinetics Analysis on Mixing Calcination Process of Fly Ash and Ammonium Sulfate

    Institute of Scientific and Technical Information of China (English)

    Peng Wang; Laishi Li; Dezhou Wei


    abstract The further development of the extraction of alumina that is produced in the calcination process of ammonium sulfate mixed with fly ash was limited because of the lack of systematic theoretical study. In order to aggrandize the research of the calcination process, the kinetics and reaction mechanism of the calcinations were studied. The result suggests that there are two stages in the calcination process, and the alumina extraction rate increases swiftly in the initial stage, but slows down increasing in the later stage. The apparent activation energy of the initial and later stages equals to 13.31 and 35.65 kJ·mol-1, respectively. In the initial stage, ammonium sulfate reacts directly with mullite in the fly ash to form ammonium aluminum sulfate, while in the later stage, alumi-num sulfate is formed by the reaction between ammonium aluminum sulfate and ammonium sulfate.

  8. Cold Case: Radar investigation of ammonium sulfate cryovolcanism on Titan (United States)

    Thomann, C.; Hayes, A. G.; Hofgartner, J.; Lunine, J. I.; Le Gall, A.


    The detection of a large tidal k2 value from Cassini [1] constitutes very strong evi-dence for a subcrustal ocean, most plausibly dominated by water. However, the secondary constituents are not known. One interesting possibility that has received scant attention in analysis of surface data sets is that the ocean contain aqueous ammonium sulfates, which erupted on the surface in the past to create vast, smooth plains [2]. We adopt the hypothesis that the undifferentiated plains—the "bland-lands" in the mid-latitudes of Titan—are these deposits, and test it using radiometry with SAR data. Lopez et al (this conference) investigate the global distribution and possible origin of this type of unit. We extracted SAR and radiometry-during-SAR data sets from the PDS, and pro-duced maps of brightness temperatures. The SAR imagery was used to identify locations where crossovers exist -some of which are in the undifferentiated plains--and hence where brightness temperatures at different incidence angles are available. We derived emissivities from the data using a simple radiometric model [3] to ac-count for the brightness temperature differences as a function of surface roughness, volume scattering and emissivity. We test the hypothesis by assessing whether the derived emissivities and volume scattering in the bland-lands are consistent with the model cryoclastic ash of ice and ammonium sulfate proposed in [2], distinct from that in other terrains. [1] L. Iess, R.A. Jacobson, M. Ducci, D.J. Stevenson, J.I. Lunine, J.W. Armstrong, S.W. Asmar, P. Racioppa, N.J. Rappaport, P. Tortora, Science, 337, 457 (2012). [2] A.D. Fortes, P.M. Grinrod, S.K. Trickett, L. Vocadlo. Icarus, 188, 139 (2007). [3] T.L. White and J.R. Cogdell. The Moon, 6, 235 (1973).

  9. Crystallization of Chicken Egg-White Lysozyme from Ammonium Sulfate (United States)

    Forsythe, Elizabeth L.; Snell, Edward H.; Pusey, Marc L.


    Chicken egg-white lysozyme was crystallized from ammonium sulfate over the pH range 4.0-7.8, with protein concentrations from 100 to 150 mg/ml. Crystals were obtained by vapor-diffusion or batch-crystallization methods. The protein crystallized in two morphologies with an apparent morphology dependence on temperature and protein concentration. In general, tetragonal crystals could be grown by lowering the protein concentration or temperature. Increasing the temperature or protein concentration resulted in the growth of orthorhombic crystals. Representative crystals of each morphology were selected for X-ray analysis. The tetragonal crystals belonged to the P4(sub 3)2(sub 1)2 space group with crystals grown at ph 4.4 having unit-cell dimensions of a = b = 78.7 1, c=38.6 A and diffracting to beyond 2.0 A. The orthorhombic crystals, grown at pH 4.8, were of space group P2(sub 1)2(sub 1)2 and had unit-cell dimensions of a = 30.51, b = 56.51 and c = 73.62 A.

  10. Depositional ice nucleation on solid ammonium sulfate and glutaric acid particles

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    K. J. Baustian


    Full Text Available Heterogeneous ice nucleation on solid ammonium sulfate and glutaric acid particles was studied using optical microscopy and Raman spectroscopy. Optical microscopy was used to detect selective nucleation events as water vapor was slowly introduced into an environmental sample cell. Particles that nucleated ice were dried via sublimation and examined in detail using Raman spectroscopy. Depositional ice nucleation is highly selective and occurred preferentially on just a few ammonium sulfate and glutaric acid particles in each sample. For freezing temperatures between 214 K and 235 K an average ice saturation ratio of S = 1.10±0.07 for solid ammonium sulfate was observed. Over the same temperature range, S values observed for ice nucleation on glutaric acid particles increased from 1.2 at 235 K to 1.6 at 218 K. Experiments with externally mixed particles further show that ammonium sulfate is a more potent ice nucleus than glutaric acid. Our results suggest that heterogeneous nucleation on ammonium sulfate may be an important pathway for atmospheric ice nucleation and cirrus cloud formation when solid ammonium sulfate aerosol particles are available for ice formation. This pathway for ice formation may be particularly significant near the tropical tropopause region where sulfates are abundant and other species known to be good ice nuclei are depleted.

  11. Isolation and identification of bacteria responsible for simultaneous anaerobic ammonium and sulfate removal

    Institute of Scientific and Technical Information of China (English)


    Sulfate-dependent anaerobic ammonium oxidation is a novel biological reaction,in which ammonium is oxidized with sulfate as the electron acceptor under anoxic conditions.Ammonium and sulfate are cosmopolitan chemical species which are an integral part of the global nitrogen and sulfur cycles.A detailed exploration of sulfate-dependent anaerobic ammonium oxidation is quite practical.In this work,a bacterial strain named ASR has been isolated from an anaerobic ammonia and sulfate removing reactor working under steady-state.On the basis of electron microscopy,physiological tests and 16S rDNA phylogenetic sequence analysis,the strain ASR is found to be related to Bacillus benzoevorans.According to the biological carbon source utilization test,the strain ASR could use many carbon sources.Its optimum pH value and temperature were 8.5 and 30 °C,respectively.The test proves that the strain ASR is able to use sulfate to oxidize ammonia anaerobically.The maximum ammonia and sulfate removal rates were 44.4% and 40.0%,respectively.The present study provided biological evidence for the confirmation and development of sulfate-dependent anaerobic ammonium oxidation and brought new insights into the global nitrogen and sulfur cycles.

  12. Sulfuric acid-ammonium sulfate aerosol: optical detection in the St. Louis region. (United States)

    Charlson, R J; Vanderpol, A H; Covert, D S; Waggnoner, A P; Ahlquist, N C


    Nephelometric sensing of the deliquescence of ammonium sulfate produced by the reaction of sulfuric acid or ammonium bisulfate aerosol with ammonia provides a means for detecting these substances in air. Field experiments show them to be the dominant substances in the submicrometer, light-scattering aerosol in the St. Louis region.

  13. Synthesis of nano-crystalline hydroxyapatite and ammonium sulfate from phosphogypsum waste

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    Mousa, Sahar, E-mail: [Inorganic Chemistry Department, National Research Centre, Dokki, P.O.Box:12622, Postal code: 11787 Cairo (Egypt); King Abdulaziz University, Science and Art College, Chemistry Department, Rabigh Campus, P.O. Box:344, Postal code: 21911 Rabigh (Saudi Arabia); Hanna, Adly [Inorganic Chemistry Department, National Research Centre, Dokki, P.O.Box:12622, Postal code: 11787 Cairo (Egypt)


    Graphical abstract: TEM micrograph of dried HAP at 800 °C. -- Abstract: Phosphogypsum (PG) waste which is derived from phosphoric acid manufacture by using wet method was converted into hydroxyapatite (HAP) and ammonium sulfate. Very simple method was applied by reacting PG with phosphoric acid in alkaline medium with adjusting pH using ammonia solution. The obtained nano-HAP was dried at 80 °C and calcined at 600 °C and 900 °C for 2 h. Both of HAP and ammonium sulfate were characterized by X-ray diffraction (XRD) and infrared spectroscopy (IR) to study the structural evolution. The thermal behavior of nano-HAP was studied; the particle size and morphology were estimated by using transmission electron microscopy (TEM) and scanning electron microscopy (SEM). All the results showed that HAP nano-crystalline and ammonium sulfate can successfully be produced from phosphogypsum waste.

  14. Precipitation of phenyl and phenoxypenicillin from solutions using ammonium sulfate. (United States)

    Luengo, J M


    An easy, rapid, and available method for separating 6-aminopenicillanic acid (6-APA), benzylpenicillin (penicillin G), and other related molecules from aqueous solutions or complex industrial broths is described. A high concentration of ammonium sulphate induces partially or totally the precipitation of the penicillin present in the solutions, while 6-APA, phenylacetic, and phenoxyacetic acid always remain in the supernatant. The filtration through No. 4 Pyrex glass-fiber filter or Whatman 3MM paper permits the separation of the compounds present in the supernatant from the other ones precipitated. The precipitated product was identified, in all cases, as ammonium penicillin. This method is described here for the first time.

  15. Ammonium Sulfate Evaporites Associated With Uranium Mill Tailings Disposal Cells (United States)

    Wendlandt, R. F.; Harrison, W. J.


    The waste products of uranium mill operations are complex and dependent on the ore mineralogy, milling process (e.g., low pH vs. high pH), and operational status of the mill among other things. The White Mesa Mill, Utah, was visited during both quiescent (July 2004) and operational phases (August 2005) to collect liquid and solid samples from the active evaporation and storage ponds environments (Cells 1 and 3). Cell 4, which was unused and being excavated at the times of both samplings, yielded solids accumulated through the history of that cell's use. Raffinate samples are concentrated Na-Mg-Al-Fe-SO4-NO3(-NH4) brines characterized by extreme enrichments in REE and transition elements. Ionic strengths, calculated using the Pitzer activity coefficient model varied from 25M (pH = 1 at 25°C) in Cell 1 and 12M (pH = 2.7) in Cell 3 during July 2004, to 5M (pH = 1.5) in Cell 1 and 1.2M (pH = 2.9) in Cell 3 during August 2005. At the first sampling, the dominant anion was sulfate in Cell 1 and nitrate in Cell 3. At the time of the second sampling, both cells were dominated by sulfate. During July 2004, there was significant evaporative drawdown in the ponds, resulting in 3 variably colored zones (~7m) of mineralogically complex evaporites at the cell margins. During August 2005, the operational nature of the mill and the addition of fresh water had produced high water levels in Cells 1 and 3. Evaporation crusts were recognized around the margins of the cells but they were <2m in extent. XRD analyses document the presence of boussingaultite, (NH4)2Mg(SO4)2.6H2O, which was actively precipitating from Cell 1 during 2004, tschermigite, (NH4)Al(SO4)2.12H2O, gypsum, and polymorphs of Na2SO4 including thenardite. ESEM imaging and EDS analyses of crusts reveal complex parageneses involving the above-mentioned phases and NH4-bearing metavoltine, K2Na6Fe^{+2}Fe6^{+3}(SO4)12O2.18H2O, among others. Ksp calculations and field relations are consistent with a precipitation sequence




    The utilization of nitrogen by sugar cane (Saccharum officinarum L.) fertilized with sunn hemp (Crotalaria juncea L.) as green manure and ammonia sulfate and its residual effect during two cuts were evaluated using 15N tracer technique. The amounts of 195.8 kg and 70 kg of N by hectare were added respectively as sunn hemp (SH) and ammonium sulfate (AS), in the following treatments: Control; AS-15N; SH-15N + AS; SH-15N; AS-15N + SH. Five samples of +3 leaves were collected and two meters of th...

  17. Solid/liquid phase diagram of the ammonium sulfate/succinic acid/water system. (United States)

    Pearson, Christian S; Beyer, Keith D


    We have studied the low-temperature phase diagram and water activities of the ammonium sulfate/succinic acid/water system using differential scanning calorimetry and infrared spectroscopy of thin films. Using the results from our experiments, we have mapped the solid/liquid ternary phase diagram, determined the water activities based on the freezing point depression, and determined the ice/succinic acid phase boundary as well as the ternary eutectic composition and temperature. We also compared our results to the predictions of the extended AIM aerosol thermodynamics model (E-AIM) and found good agreement for the ice melting points in the ice primary phase field of this system; however, differences were found with respect to succinic acid solubility temperatures. We also compared the results of this study with those of previous studies that we have published on ammonium sulfate/dicarboxylic acid/water systems.

  18. Optimization of tetanus toxoid ammonium sulfate precipitation process using response surface methodology. (United States)

    Brgles, Marija; Prebeg, Pero; Kurtović, Tihana; Ranić, Jelena; Marchetti-Deschmann, Martina; Allmaier, Günter; Halassy, Beata


    Tetanus toxoid (TTd) is a highly immunogenic, detoxified form of tetanus toxin, a causative agent of tetanus disease, produced by Clostridium tetani. Since tetanus disease cannot be eradicated but is easily prevented by vaccination, the need for the tetanus vaccine is permanent. The aim of this work was to investigate the possibility of optimizing TTd purification, i.e., ammonium sulfate precipitation process. The influence of the percentage of ammonium sulfate, starting amount of TTd, buffer type, pH, temperature, and starting purity of TTd on the purification process were investigated using optimal design for response surface models. Responses measured for evaluation of the ammonium sulfate precipitation process were TTd amount (Lf/mL) and total protein content. These two parameters were used to calculate purity (Lf/mgPN) and the yield of the process. Results indicate that citrate buffer, lower temperature, and lower starting amount of TTd result in higher purities of precipitates. Gel electrophoresis combined with matrix-assisted laser desorption ionization-mass spectrometric analysis of precipitates revealed that there are no inter-protein cross-links and that all contaminating proteins have pIs similar to TTd, so this is most probably the reason for the limited success of purification by precipitation.

  19. Manufacture of ammonium sulfate fertilizer from gypsum-rich byproduct of flue gas desulfurization - A prefeasibility cost estimate (United States)

    Chou, I.-Ming; Rostam-Abadi, M.; Lytle, J.M.; Achorn, F.P.


    Costs for constructing and operating a conceptual plant based on a proposed process that converts flue gas desulfurization (FGD)-gypsum to ammonium sulfate fertilizer has been calculated and used to estimate a market price for the product. The average market price of granular ammonium sulfate ($138/ton) exceeds the rough estimated cost of ammonium sulfate from the proposed process ($111/ ton), by 25 percent, if granular size ammonium sulfate crystals of 1.2 to 3.3 millimeters in diameters can be produced by the proposed process. However, there was at least ??30% margin in the cost estimate calculations. The additional costs for compaction, if needed to create granules of the required size, would make the process uneconomical unless considerable efficiency gains are achieved to balance the additional costs. This study suggests the need both to refine the crystallization process and to find potential markets for the calcium carbonate produced by the process.

  20. Formation and transformation of metastable double salts from the crystallization of mixed ammonium nitrate and ammonium sulfate particles. (United States)

    Ling, Tsz Yan; Chan, Chak K


    Ammonium nitrate (AN) and ammonium sulfate (AS) are ubiquitous components of atmospheric aerosols. Thermodynamic models predict formation of pure (AN and AS) and double salts (3AN. AS and 2AN. AS) for the AN/AS system. Because of the high supersaturation at which a droplet crystallizes, metastable crystal formation is possible. In this study, the identity of the crystals formed from the crystallization of equimolar AN/AS mixed droplets was investigated in an electrodynamic balance coupled with a Raman spectroscopic system. Raman spectra of bulk AN/AS double salts possibly formed in this system are first reported for comparison with the single particle Raman results. The double-salt 3AN. AS, not predicted from thermodynamics, was observed in the freshly crystallized single particles. The degree of metastability can be different among several crystallization processes of the same particles. The metastable salt 3AN. AS gradually transformed into stable 2AN. AS, and the rate of such transformation increased with increasing relative humidity. This study illustrates the possibility of occurrence of metastable salts in atmospheric aerosols.


    Institute of Scientific and Technical Information of China (English)

    Meigen Zhang


    The transport and chemical production processes of nitrate, sulfate, and ammonium aerosols over East Asia were investigated by use of the Models-3 Community Multi-scale Air Quality (CMAQ) modeling system coupled with the Regional Atmospheric Modeling System (RAMS). For the evaluation of the model's ability in depicting their3-dimensional concentration distributions and temporal variations, modeled concentrations of nitrate, sulfate, and ammonium aerosols are compared with the observations obtained at a ground station in Japan in March 2001 and onboard of an aircraft DC-8 on 18 and 21 March 2001 during the Transport and Chemical Evolution over the Pacific (TRACE-P)field campaign. Comparison shows that simulated values of nitrate, sulfate, and ammonium aerosols are generally in good agreement with their observed data, and the model captures most important observed features, and reproduces temporal and spatial variations of nitrate, sulfate, and ammonium aerosol concentrations reasonably well, e.g., the timing and locations of the concentration spikes of nitrate, sulfate, and ammonium aerosols are well reproduced, but large discrepancies between observed and simulated values are also clearly seen at some points and some times due to the coarse grid resolution and uncertainties of the emissions used in this study. This comparison results indicate that CMAQ is able to simulate the distributions of nitrate, sulfate, and ammonium aerosols and their related species in the troposphere over East Asia reasonably well.

  2. Management of ammonium sulfate fertilization on productive performance of corn grown after oats and wheat

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    Maria Anita Gonçalves Silva


    Full Text Available The time, dose and applied nutrients in corn have a direct effect on its productivity. Therefore, the objective was to study the application of N and S in corn as ammonium sulfate, in succession to wheat and oats and evaluate different forms of fertilizer management. The experiment was conducted in a randomized block design in Oxisol (Hapludox. The five treatments with N, at a dose of 120 kg ha-1 were applied in 20 plots (5x4, according to the management of fertilizer: T1-N (120 kg ha-1 full at sowing, T2-N (120 kg ha-1 total coverage; T3 –N (40 kg ha-1 at sowing and N (80 kg ha-1 in coverage; T4-N advance in wheat sowing and sowing oats (120 kg ha-1, T5- (control. The S doses were corresponding to their concentrations in the fertilizer. Only wheat received a dose of 24 kg N ha-1 at sowing all plots and oats received 24 kg N ha- 1 at sowing only the portions related to treatment with anticipation of corn N ( T4 . We evaluated the biomass production of winter crops (oats and wheat, according to the fertilization at sowing, and also the influence of winter crops and management of ammonium sulfate, the corn yield. The oats produced more dry matter in relation to wheat, positively influencing the corn yield, regardless of fertilizer management. The anticipation of ammonium sulfate, the sowing of oats, was favorable to corn yield, equating to other forms of management of fertilizer. Rotation corn and oats, forms management, ammonium sulphate, at seeding, topdressing or applied in split were equally efficient in corn yields.

  3. Formation of hexamethylenetetramine by aqueous solutions of formaldehyde and ammonium sulfate (United States)

    Rodriguez, A. A.; De Haan, D. O.; Kua, J.


    Formaldehyde and ammonium sulfate are prominent compounds found in cloudwater. Electronic structure calculations and lab experiments were carried out to explore the oligomerization reactions between formaldehyde and ammonia. Density functional theory calculations along with solvation and thermodynamic corrections were performed to map the kinetic and thermodynamic landscape for the reactions leading to the formation of hexamethylenetetramine (hmta). Three general classes of reactions were considered: nucleophilic addition of amine to formaldehyde, nucleophilic addition of ammonia to imine intermediates ammonia, and dehydration of alkanolamines. The reaction was studied experimentally using bulk-phase aqueous solutions of formaldehyde, ammonium sulfate, and in some experiments, iron (III) sulfate (chosen because Fe3+ forms a brown complex with hmta). Aqueous standard solutions of the reaction product hmta were also made. Reaction mixtures were analyzed using NMR, UV-Vis spectroscopy and LCMS. Compound hmta was the main product observed by both NMR and LCMS. Using LCMS a large peak was observed within minutes of mixing the reactants. The absorbance of the reaction mixture increased strongly below 225 nm but little to no absorbance was observed in the visible spectrum.

  4. Synthesis and surface-active property of bis-quaternary ammonium-sodium sulfate Gemini surfactant

    Institute of Scientific and Technical Information of China (English)

    Zhao Qiuling; Gao Zhinong


    N,N-dimethyldodecylamine,hydrochloride and epichlorohydrin (molar ration is 2:1:1) were used to synthesize bis-quaternary ammonium Gemini surfactant with a hydroxyl in its spacer group by the one-pot method.This hydroxyl was sulfonated by chlorosulfonic acid and then neutralized to bis-quaternary ammonium-sodium sulfate zwitterionic Gemini surfactant.The yield of the final product was 78%,and the melting point was 231-233℃.Its structure was characterized by IR,1H-NMR,MS,and elemental analyses.The critical micelle concentration (cmc)and surface tension of the novel zwitterionic Gemini surfactant in aqueous solution at 15℃ are 7.2×10-5 mol/L and 34.5 mN/m,respectively.

  5. Removal of hydrogen sulfide as ammonium sulfate from hydropyrolysis product vapors

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    Marker, Terry L.; Felix, Larry G.; Linck, Martin B.; Roberts, Michael J.


    A system and method for processing biomass into hydrocarbon fuels that includes processing a biomass in a hydropyrolysis reactor resulting in hydrocarbon fuels and a process vapor stream and cooling the process vapor stream to a condensation temperature resulting in an aqueous stream. The aqueous stream is sent to a catalytic reactor where it is oxidized to obtain a product stream containing ammonia and ammonium sulfate. A resulting cooled product vapor stream includes non-condensable process vapors comprising H.sub.2, CH.sub.4, CO, CO.sub.2, ammonia and hydrogen sulfide.

  6. Experimental Investigation on Pool Boiling Heat Transfer With Ammonium Dodecyl Sulfate

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    Mr.P. Atcha Rao


    Full Text Available We have so many applications related to Pool Boiling. The Pool Boiling is mostly useful in arid areas to produce drinking water from impure water like sea water by distillation process. It is very difficult to distill the only water which having high surface tension. The surface tension is important factor to affect heat transfer enhancement in pool boiling. By reducing the surface tension we can increase the heat transfer rate in pool boiling. From so many years we are using surfactants domestically. It is proven previously by experiments that the addition of little amount of surfactant reduces the surface tension and increase the rate of heat transfer. There are different groups of surfactants. From those I‟m conducting experimentation with anionic surfactant Ammonium Dodecyl Sulfate (ADS, which is most human friendly and three times best soluble than Sodium Dodecyl Sulfate, to test the heat transfer enhancement.

  7. Volatility of mixed atmospheric humic-like substances and ammonium sulfate particles (United States)

    Nie, Wei; Hong, Juan; Häme, Silja A. K.; Ding, Aijun; Li, Yugen; Yan, Chao; Hao, Liqing; Mikkilä, Jyri; Zheng, Longfei; Xie, Yuning; Zhu, Caijun; Xu, Zheng; Chi, Xuguang; Huang, Xin; Zhou, Yang; Lin, Peng; Virtanen, Annele; Worsnop, Douglas R.; Kulmala, Markku; Ehn, Mikael; Yu, Jianzhen; Kerminen, Veli-Matti; Petäjä, Tuukka


    The volatility of organic aerosols remains poorly understood due to the complexity of speciation and multiphase processes. In this study, we extracted humic-like substances (HULIS) from four atmospheric aerosol samples collected at the SORPES station in Nanjing, eastern China, and investigated the volatility behavior of particles at different sizes using a Volatility Tandem Differential Mobility Analyzer (VTDMA). In spite of the large differences in particle mass concentrations, the extracted HULIS from the four samples all revealed very high-oxidation states (O : C > 0.95), indicating secondary formation as the major source of HULIS in Yangtze River Delta (YRD). An overall low volatility was identified for the extracted HULIS, with the volume fraction remaining (VFR) higher than 55 % for all the regenerated HULIS particles at the temperature of 280 °C. A kinetic mass transfer model was applied to the thermodenuder (TD) data to interpret the observed evaporation pattern of HULIS, and to derive the mass fractions of semi-volatile (SVOC), low-volatility (LVOC) and extremely low-volatility components (ELVOC). The results showed that LVOC and ELVOC dominated (more than 80 %) the total volume of HULIS. Atomizing processes led to a size-dependent evaporation of regenerated HULIS particles, and resulted in more ELVOC in smaller particles. In order to understand the role of interaction between inorganic salts and atmospheric organic mixtures in the volatility of an organic aerosol, the evaporation of mixed samples of ammonium sulfate (AS) and HULIS was measured. The results showed a significant but nonlinear influence of ammonium sulfate on the volatility of HULIS. The estimated fraction of ELVOC in the organic part of the largest particles (145 nm) increased from 26 %, in pure HULIS samples, to 93 % in 1 : 3 (mass ratio of HULIS : AS) mixed samples, to 45 % in 2 : 2 mixed samples, and to 70 % in 3 : 1 mixed samples, suggesting that the interaction with ammonium sulfate

  8. The optical constants of several atmospheric aerosol species - Ammonium sulfate, aluminum oxide, and sodium chloride (United States)

    Toon, O. B.; Pollack, J. B.; Khare, B. N.


    An investigation is conducted of problems which are related to a use of measured optical constants in the simulation of the optical constants of real atmospheric aerosols. The techniques of measuring optical constants are discussed, taking into account transmission measurements through homogeneous and inhomogeneous materials, the immersion of a material in a liquid of a known refractive index, the consideration of the minimum deviation angle of prism measurement, the interference of multiply reflected light, reflectivity measurements, and aspects of mathematical analysis. Graphs show the real and the imaginary part of the refractive index as a function of wavelength for aluminum oxide, NaCl, and ammonium sulfate. Tables are provided for the dispersion parameters and the optical constants.

  9. A study of the phase transition behavior of internally mixed ammonium sulfate - malonic acid aerosols

    Directory of Open Access Journals (Sweden)

    C. F. Braban


    Full Text Available This is a study into the phase transitions of aerosol composed of the ternary system ammonium sulfate (AS - malonic acid (MA - water using infrared extinction spectroscopy. Twelve compositions were studied in both deliquescence and efflorescence mode experiments. The presence of a MA fraction, by dry mass, (fMA of 0.1 in an AS aerosol altered the relative humidity at which the phase transitions occur in an atmospherically significant manner. For compositions with 0.25fMAfMA=0.9, the crystallization relative humidity of MA was lowered from RH=6% to less than 1%. Similarly, at fMA=0.4, the AS component did not crystallize. The atmospheric implications of the results are discussed.

  10. Hygroscopic behavior of multicomponent organic aerosols and their internal mixtures with ammonium sulfate

    Directory of Open Access Journals (Sweden)

    B. Jing


    Full Text Available Water soluble organic compounds (WSOCs are important components of organics in the atmospheric fine particulate matter. Although WSOCs play an important role in the hygroscopicity of aerosols, water uptake behavior of internally mixed WSOC aerosols remains limited characterization. Here, the hygroscopic properties of single component such as levoglucosan, oxalic acid, malonic acid, succinic acid and phthalic acid and multicomponent WSOC aerosols mainly involving oxalic acid are investigated with the hygroscopicity tandem differential mobility analyzer (HTDMA. The coexisting hygroscopic species including levoglucosan, malonic acid and phthalic acid have strong influence on the hygroscopic growth and phase behavior of oxalic acid, even suppress its crystallization completely. The interactions between oxalic acid and levoglucosan are confirmed by infrared spectra. The discrepancies between measured growth factors and predictions from Extended Aerosol Inorganics Model (E-AIM with UNIFAC method and Zdanovskii–Stokes–Robinson (ZSR approach increase at medium and high relative humidity (RH assuming oxalic acid in a solid state. For the internal mixture of oxalic acid with levoglucosan or succinic acid, there is enhanced water uptake at high RH due to positive chemical interactions between solutes. Organic mixture has more complex effect on the hygroscopicity of ammonium sulfate than single species. Although hygroscopic species such as levoglucosan accounts for a small fraction in the multicomponent aerosols, they may still strongly influence the hygroscopic behavior of ammonium sulfate by changing phase state of oxalic acid which plays the role of "intermediate" species. Considering the abundance of oxalic acid in the atmospheric aerosols, its mixtures with hygroscopic species may significantly promote water uptake under high RH conditions and thus affect the cloud condensation nuclei (CCN activity, optical properties and chemical reactivity of

  11. Hygroscopic and phase separation properties of ammonium sulfate/organic/water ternary solutions (United States)

    Zawadowicz, M. A.; Proud, S. R.; Seppalainen, S. S.; Cziczo, D. J.


    Atmospheric aerosol particles are often partially or completely composed of inorganic salts, such as ammonium sulfate and sodium chloride, and therefore exhibit hygroscopic properties. Many inorganic salts have well-defined deliquescence and efflorescence points at which they take up and lose water, respectively. Deliquescence and efflorescence of simple inorganic salt particles have been investigated by a variety of methods, such as IR spectroscopy, tandem mobility analysis and electrodynamic balance. Field measurements have shown that atmospheric aerosols are not typically pure inorganic salt, instead they often also contain organic species. There is ample evidence from laboratory studies that suggests that mixed particles exist in a phase-separated state, with an aqueous inorganic core and organic shell. Although phase separation has not been measured in situ, there is no reason it would not also take place in the atmosphere. Many recent studies have focused on microscopy techniques that require deposition of the aerosol on a glass slide, possibly changing its surface properties. Here, we investigate the deliquescence and efflorescence points, phase separation and ability to exchange gas-phase components of mixed organic and inorganic aerosol using a flow tube coupled with FTIR spectroscopy. Ammonium sulfate aerosol mixed with organic polyols with different O : C ratios, including 1,4-butanediol, glycerol, 1,2,6-hexanetriol, 1,2-hexanediol, and 1,5-pentanediol have been investigated. Those constituents correspond to materials found in the atmosphere in great abundance, and therefore, particles prepared in this study should mimic atmospheric mixed phase aerosol particles. The results of this study tend to be in agreement with previous microscopy experiments, with several key differences, which possibly reveal a size-dependent effect on phase separation in organic/inorganic aerosol particles.

  12. Hygroscopic and phase separation properties of ammonium sulfate/organics/water ternary solutions (United States)

    Zawadowicz, M. A.; Proud, S. R.; Seppalainen, S. S.; Cziczo, D. J.


    Atmospheric aerosol particles are often partially or completely composed of inorganic salts, such as ammonium sulfate and sodium chloride, and therefore exhibit hygroscopic properties. Many inorganic salts have well-defined deliquescence and efflorescence points at which they take up and lose water, respectively. Field measurements have shown that atmospheric aerosols are not typically pure inorganic salt, instead, they often also contain organic species. There is ample evidence from laboratory studies that suggests that mixed particles exist in a phase-separated state, with an aqueous inorganic core and organic shell. Although phase separation has not been measured in situ, there is no reason it would not also take place in the atmosphere. Here, we investigate the deliquescence and efflorescence points, phase separation and ability to exchange gas-phase components of mixed organic and inorganic aerosol using a flow tube coupled with FTIR (Fourier transform infrared) spectroscopy. Ammonium sulfate aerosol mixed with organic polyols with different O : C ratios, including 1,4-butanediol, glycerol, 1,2,6-hexanetriol, 1,2-hexanediol, and 1,5-pentanediol have been investigated. Those constituents correspond to materials found in the atmosphere in great abundance and, therefore, particles prepared in this study should mimic atmospheric mixed-phase aerosol particles. Some results of this study tend to be in agreement with previous microscopy experiments, but others, such as phase separation properties of 1,2,6-hexanetriol, do not agree with previous work. Because the particles studied in this experiment are of a smaller size than those used in microscopy studies, the discrepancies found could be a size-related effect.

  13. Hygroscopic and phase separation properties of ammonium sulfate/organic/water ternary solutions

    Directory of Open Access Journals (Sweden)

    M. A. Zawadowicz


    Full Text Available Atmospheric aerosol particles are often partially or completely composed of inorganic salts, such as ammonium sulfate and sodium chloride, and therefore exhibit hygroscopic properties. Many inorganic salts have well-defined deliquescence and efflorescence points at which they take up and lose water, respectively. Deliquescence and efflorescence of simple inorganic salt particles have been investigated by a variety of methods, such as IR spectroscopy, tandem mobility analysis and electrodynamic balance. Field measurements have shown that atmospheric aerosols are not typically pure inorganic salt, instead they often also contain organic species. There is ample evidence from laboratory studies that suggests that mixed particles exist in a phase-separated state, with an aqueous inorganic core and organic shell. Although phase separation has not been measured in situ, there is no reason it would not also take place in the atmosphere. Many recent studies have focused on microscopy techniques that require deposition of the aerosol on a glass slide, possibly changing its surface properties. Here, we investigate the deliquescence and efflorescence points, phase separation and ability to exchange gas-phase components of mixed organic and inorganic aerosol using a flow tube coupled with FTIR spectroscopy. Ammonium sulfate aerosol mixed with organic polyols with different O : C ratios, including 1,4-butanediol, glycerol, 1,2,6-hexanetriol, 1,2-hexanediol, and 1,5-pentanediol have been investigated. Those constituents correspond to materials found in the atmosphere in great abundance, and therefore, particles prepared in this study should mimic atmospheric mixed phase aerosol particles. The results of this study tend to be in agreement with previous microscopy experiments, with several key differences, which possibly reveal a size-dependent effect on phase separation in organic/inorganic aerosol particles.

  14. Effects of the physical state of tropospheric ammonium-sulfate-nitrate particles on global aerosol direct radiative forcing

    Directory of Open Access Journals (Sweden)

    S. T. Martin


    Full Text Available The effect of aqueous versus crystalline sulfate-nitrate-ammonium tropospheric particles on global aerosol direct radiative forcing is assessed. A global three-dimensional chemical transport model predicts sulfate, nitrate, and ammonium aerosol mass. An aerosol thermodynamics model is called twice, once for the upper side (US and once for lower side (LS of the hysteresis loop of particle phase. On the LS, the sulfate mass budget is 40% solid ammonium sulfate, 12% letovicite, 11% ammonium bisulfate, and 37% aqueous. The LS nitrate mass budget is 26% solid ammonium nitrate, 7% aqueous, and 67% gas-phase nitric acid release due to increased volatility upon crystallization. The LS ammonium budget is 45% solid ammonium sulfate, 10% letovicite, 6% ammonium bisulfate, 4% ammonium nitrate, 7% ammonia release due to increased volatility, and 28% aqueous. LS aerosol water mass partitions as 22% effloresced to the gas-phase and 78% remaining as aerosol mass. The predicted US/LS global fields of aerosol mass are employed in a Mie scattering model to generate global US/LS aerosol optical properties, including scattering efficiency, single scattering albedo, and asymmetry parameter. Global annual average LS optical depth and mass scattering efficiency are, respectively, 0.023 and 10.7 m2 (g SO4-2-1, which compare to US values of 0.030 and 13.9 m2 (g SO4-2-1. Radiative transport is computed, first for a base case having no aerosol and then for the two global fields corresponding to the US and LS of the hysteresis loop. Regional, global, seasonal, and annual averages of top-of-the-atmosphere aerosol radiative forcing on the LS and US (FL and FU, respectively, in W m-2 are calculated. Including both anthropogenic and natural emissions, we obtain global annual averages of FL=-0.750, FU=-0.930, and DFU,L=24% for full sky calculations without clouds and FL=-0.485, FU=-0.605, and DFU,L=25% when clouds are included. Regionally, DFU,L=48% over the USA, 55% over Europe

  15. Modeling the spectral optical properties of ammonium sulfate and biomass burning aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Grant, K.E.; Chuang, C.C.; Grossman, A.S.; Penner, J.E. [Michigan Univ., Ann Arbor, MI (United States)


    The importance of including the global and regional radiative effects of aerosols in climate models has increasingly been realized. Accurate modeling of solar radiative forcing due to aerosols from anthropogenic sulfate and biomass burning emissions requires adequate spectral resolution and treatment of spatial and temporal variability. The variation of aerosol spectral optical properties with local relative humidity and dry aerosol composition must be considered. Because the cost of directly including Mie calculations within a climate model is prohibitive, parameterizations from offline calculations must be used. Starting from a log-normal size distribution of dry ammonium sulfate, we developed optical properties for tropospheric sulfate aerosol at 15 relative humidities up to 99 percent. The resulting aerosol size distributions were then used to calculate bulk optical properties at wavelengths between 0.175 {micro}m and 4 {micro}m. Finally, functional fits of optical properties were made for each of 12 wavelength bands as a function of relative humidity. Significant variations in optical properties occurred across the total solar spectrum. Relative increases in specific extinction and asymmetry factor with increasing relative humidity became larger at longer wavelengths. Significant variation in single-scattering albedo was found only in the longest near-IR band. This is also the band with the lowest albedo. A similar treatment was done for aerosols from biomass burning. In this case, size distributions were taken as having two carbonaceous size modes and a larger dust mode. The two carbonaceous modes were considered to be humidity dependent. Equilibrium size distributions and compositions were calculated for 15 relative humidities and five black carbon fractions. Mie calculations and Chandrasekhar averages of optical properties were done for each of the resulting 75 cases. Finally, fits were made for each of 12 spectral bands as functions of relative humidity

  16. Assessment of the first indirect radiative effect of ammonium-sulfate-nitrate aerosols in East Asia (United States)

    Han, Xiao; Zhang, Meigen; Skorokhod, Andrei


    A physically based cloud nucleation parameterization was introduced into an optical properties/radiative transfer module incorporated with the off-line air quality modeling system Regional Atmospheric Modeling System (RAMS)-Models-3 Community Multi Scale Air Quality (CMAQ) to investigate the distribution features of the first indirect radiative effects of sulfate, nitrate, and ammonium-sulfate-nitrate (ASN) over East Asia for the years of 2005, 2010, and 2013. The relationship between aerosol particles and cloud droplet number concentration could be properly described by this parameterization because the simulated cloud fraction and cloud liquid water path were generally reliable compared with Moderate Resolution Imaging Spectroradiometer (MODIS) retrieved data. Simulation results showed that the strong effect of indirect forcing was mainly concentrated in Southeast China, the East China Sea, the Yellow Sea, and the Sea of Japan. The highest indirect radiative forcing of ASN reached -3.47 W m-2 over Southeast China and was obviously larger than the global mean of the indirect forcing of all anthropogenic aerosols. In addition, sulfate provided about half of the contribution to the ASN indirect forcing effect. However, the effect caused by nitrate was weak because the mass burden of nitrate was very low during summer, whereas the cloud fraction was the highest. The analysis indicated that even though the interannual variation of indirect forcing magnitude generally followed the trend of aerosol mass burden from 2005 to 2013, the cloud fraction was an important factor that determined the distribution pattern of indirect forcing. The heaviest aerosol loading in North China did not cause a strong radiative effect because of the low cloud fraction over this region.

  17. Simulation of nitrate, sulfate, and ammonium aerosols over the United States

    Directory of Open Access Journals (Sweden)

    J. M. Walker


    Full Text Available Atmospheric concentrations of inorganic gases and aerosols (nitrate, sulfate, and ammonium are simulated for 2009 over the United States using the chemical transport model GEOS-Chem. Predicted aerosol concentrations are compared with surface-level measurement data from the Interagency Monitoring of Protected Visual Environments (IMPROVE, the Clean Air Status and Trends Network (CASTNET, and the California Air Resources Board (CARB. Sulfate predictions nationwide are in reasonably good agreement with observations, while nitrate and ammonium are over-predicted in the East and Midwest, but under-predicted in California, where observed concentrations are the highest in the country. Over-prediction of nitrate in the East and Midwest is consistent with results of recent studies, which suggest that nighttime nitric acid formation by heterogeneous hydrolysis of N2O5 is over-predicted based on current values of the N2O5 uptake coefficient, γ, onto aerosols. After reducing the value of γ by a factor of 10, predicted nitrate levels in the US Midwest and East still remain higher than those measured, and over-prediction of nitrate in this region remains unexplained. Comparison of model predictions with satellite measurements of ammonia from the Tropospheric Emissions Spectrometer (TES indicates that ammonia emissions in GEOS-Chem are underestimated in California and that the nationwide seasonality applied to ammonia emissions in GEOS-Chem does not represent California very well, particularly underestimating winter emissions. An ammonia sensitivity study indicates that GEOS-Chem simulation of nitrate is ammonia-limited in southern California and much of the state, suggesting that an underestimate of ammonia emissions is likely the main cause for the under-prediction of nitrate aerosol in many areas of California. An approximate doubling of ammonia emissions is needed to reproduce observed nitrate concentrations in

  18. Joint enhancement of lead accumulation in Brassica plants by EDTA and ammonium sulfate in sand culture

    Institute of Scientific and Technical Information of China (English)


    When EDTA was added alone in the Pb-contaminated sand, the plant biomass and the total Pb amount in plant decreased in both species, Brassica pekinensis and B. juncea var. multiceps, though the shoot Pb amount increased. In contrast, when (NH4)2 SO4 was added alone in the Pb-contaminated sand, little effect was observed on the shoot Pb amount, though the root Pb amount was significantly increased in B. juncea var. multiceps. When amending EDTA and (NH4)2SO4 in combination, however, the shoot Pb amount in both species substantially increased, being, on an average, 2 times and 9 times higher than that in EDTA alone or (NH4)2 SO4 alone amended treatment, respectively.The two amendments showed antagonism for plant growth, but synergism for Pb bioaccumulation. B. pekinensis showed its highest level of shoot and total Pb amount in the treatment amended with EDTA and (NH4)2 SO4 only a half as much as in the other treatments. It is inferred that the mechanisms responsible for the joint-enhanced Pb accumulation might be concerned with the acidification of the growth medium, cation exchange reaction and relieving EDTA induced toxicity as results by amending ammonium sulfate.

  19. Nitrous Oxide and Methane Fluxes Following Ammonium Sulfate and Vinasse Application on Sugar Cane Soil. (United States)

    Paredes, Debora da S; Alves, Bruno J R; dos Santos, Marco A; Bolonhezi, Denizart; Sant'Anna, Selenobaldo A C; Urquiaga, Segundo; Lima, Magda A; Boddey, Robert M


    This study aimed to quantify nitrous oxide (N2O) and methane (CH4) emission/sink response from sugar cane soil treated with fertilizer nitrogen (N) and vinasse applied separately or in sequence, the latter being investigated with regard to the time interval between applications for a possible effect on emissions. The study was carried out in a traditional area of unburned sugar cane in São Paulo state, Brazil. Two levels of N fertilization (0 and 100 kg N ha(-1)) with no added vinasse and combined with vinasse additions at different times (100 m(-3) ha(-1) at 3 and 15 days after N fertilization) were evaluated. Methane and N2O fluxes were monitored for 211 days. On average, the soil was a sink for CH4, which was not affected by the treatments. Emissions of N2O were induced by N fertilizer and vinasse applications. For ammonium sulfate, 0.6% of the added N was emitted as N2O, while for vinasse, this ranged from 1.0 to 2.2%. Changes in N2O fluxes were detected the day after application of vinasse on the N fertilized areas, but although the emission factor (EF) was 34% greater, the EF was not significantly different from fertilizer N alone. Nevertheless, we recommend to not apply vinasse after N fertilization to avoid boosting N2O emissions.

  20. Effects of ammonium sulfate aerosols on vegetation—II. Mode of entry and responses of vegetation (United States)

    Gmur, Nicholas F.; Evans, Lance S.; Cunningham, Elizabeth A.

    These experiments were designed to provide information on the rates of aerosol deposition, mode of entry, and effects of deposition of submicrometer ammonium sulfate aerosols on foliage of Phaseolus vulgaris L. A deposition velocity of 3.2 × 10 3cms-1 was constant during 3-week exposures of plants to aerosol concentrations of 26mg m -3 (i.e. about two orders of magnitude above ambient episode concentrations). Mean deposition rate on foliage was 4.1 × 10 -11 μg cm -2s -1. Visible injury symptoms included leaf chlorosis, necrosis and loss of turgor. Chlorosis was most frequent near leaf margins causing epinasty and near major veins. Internal injury occurred initially in spongy mesophyll cells. Eventually abaxial epidermal and palisade parenchyma cells were injured. These results suggest that submicrometer aerosols enter abaxial stomata and affect more internal cells before affecting leaf surface cells. Exposure to aerosols decreased both abaxial and adaxial leaf resistances markedly. Although visible injury to foliage occurred, no changes in dry mass of roots and shoots or leaf area occurred. These results suggest that for the plant developmental stage studied, while leaf resistances decreased and cellular injury occurred in foliage, these factors were not significantly related to plant growth and development.

  1. Effects of ammonium sulfate aerosols on vegetation--II. Mode of entry and responses of vegetation

    Energy Technology Data Exchange (ETDEWEB)

    Gmur, N.F. (Brookhaven National Lab., Upton, NY); Evans, L.S.; Cunningham, E.A.


    These experiments were designed to provide information on the rates of aerosol deposition, mode of entry, and effects of deposition of submicrometer ammonium sulfate aerosols on foliage of Phaseolus vulgaris L. A deposition velocity of 3.2 x 10/sup -3/ cm s/sup -1/ was constant during 3-week exposures of plants to aerosol concentrations of 26mg m/sup -3/ (i.e., about two orders of magnitude above ambient episode concentrations). Mean deposition rate on foliage was 4.1 x 10/sup -11/ cm/sup -2/ s/sup -1/. Visible injury symptoms included leaf chlorosis, necrosis, and loss of turgor. Chlorosis was most frequent near leaf margins causing epinasty and near major veins. Internal injury occurred initially in spongy mesophyll cells. Eventually abaxial epidermal and palisade parenchyma cells were injured. These results suggest that submicrometer aerosols enter abaxial stomata and affect more internal cells before affecting leaf surface cells. Exposure to aerosols decreased both abaxial and adaxial leaf resistances markedly. Although visible injury to foliage occurred, no change in dry mass of roots and shoots or leaf area occurred. These results suggest that for the plant developmental stage studied, while leaf resistances decreased and cellular injury occurred in foliage, these factors were not significantly related to plant growth and development.

  2. Revealing Brown Carbon Chromophores Produced in Reactions of Methylglyoxal with Ammonium Sulfate

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Peng; Laskin, Julia; Nizkorodov, Sergey A.; Laskin, Alexander


    Atmospheric brown carbon (BrC) is an important contributor to light absorption and climate forcing by aerosols. Reactions between small water-soluble carbonyls and ammonia or amines have been identified as one of the potential pathways of BrC formation. However, detailed chemical characterization of BrC chromophores has been challenging and their formation mechanisms are still poorly understood. Understanding BrC formation is impeded by the lack of suitable methods which can unravel the variability and complexity of BrC mixtures. This study applies high performance liquid chromatography (HPLC) coupled to photodiode array (PDA) detector and high resolution mass spectrometry (HRMS) to investigate optical properties and chemical composition of individual BrC components produced through reactions of methylglyoxal (MG) and ammonium sulfate (AS), both of which are abundant in the atmospheric environment. A direct relationship between optical properties and chemical composition of 30 major BrC chromophores was established. Nearly all of these chromophores are nitrogen-containing compounds that account for >70% of the overall light absorption by the MG+AS system in the 300-500 nm range. These results suggest that reduced-nitrogen organic compounds formed in reactions between atmospheric carbonyls and ammonia/amines are important BrC chromophores. It is also demonstrated that improved separation of BrC chromophores by HPLC will significantly advance understanding of BrC chemistry.

  3. A study of the phase transition behavior of mixed ammonium sulfate – malonic acid aerosols

    Directory of Open Access Journals (Sweden)

    C. F. Braban


    Full Text Available This is a study into the phase transitions of aerosol composed of the ternary system ammonium sulfate (AS – malonic acid (MA – water using infrared extinction spectroscopy. Twelve compositions were studied in both deliquescence and efflorescence mode experiments. The presence of a MA fraction, by dry mass, (fMA of 0.1 in an AS aerosol altered the relative humidity at which the phase transitions occur in an atmospherically significant manner. For compositions with 0.25<fMA<0.90, no distinct "deliquescence" was observed, contrary to the observed behavior in the binary systems. The crystallization of both the MA and AS components is suppressed by the presence of the other component in the aerosol. At fMA=0.9, the crystallization relative humidity of MA was lowered from RH=6% to less than 1%. Similarly, at fMA=0.4, the AS component did not crystallize. The atmospheric implications of the results are discussed.

  4. Modified ferrous ammonium sulfate benzoic acid xyelenol orange (MFBX) and thermoluminescent dosimeters--a comparative study. (United States)

    Brindha, S; Rose, J V R; Sathyan, S; Singh I, Rabi Raja; Ravindran, B Paul


    Radiation dosimetry deals with the determination of absorbed dose to the medium exposed to ionizing radiation. Chemical dosimetry depends on oxidation or reduction of chemicals by ionizing radiation. A ferrous ammonium sulfate benzoic acid xyelenol orange (FBX) dosimeter based on this principle is being used as a clinical dosimeter at present. Certain modifications were carried out in the preparation and storage of the FBX dosimeter to increase its shelf life. The resulting dosimeter was called a modified FBX (MFBX) dosimeter and has been used in our department for the past few years. An extensive study of the dose, dose rate and energy response of the dosimeter was carried out and compared with a thermoluminescent (LiF7) dosimeter. The results obtained were found to be comparable to the thermoluminescent (LiF7) dosimeter. Hence it was concluded that the MFBX dosimeter could be used for phantom dosimetry, data collection and in vivo measurements. Easier preparation and availability of the reagents are added advantages of using MFBX as a clinical dosimeter in small radiotherapy departments.

  5. Induced binding of proteins by ammonium sulfate in affinity and ion-exchange column chromatography. (United States)

    Arakawa, Tsutomu; Tsumoto, Kouhei; Ejima, Daisuke; Kita, Yoshiko; Yonezawa, Yasushi; Tokunaga, Masao


    In general, proteins bind to affinity or ion-exchange columns at low salt concentrations, and the bound proteins are eluted by raising the salt concentration, changing the solvent pH, or adding competing ligands. Blue-Sepharose is often used to remove bovine serum albumin (BSA) from samples, but when we applied BSA to Blue-Sepharose in 20 mM phosphate, pH 7.0, 50%-60% of the protein flowed through the column; however, complete binding of BSA was achieved by the addition of 2 M ammonium sulfate (AS) to the column equilibration buffer and the sample. The bound protein was eluted by decreasing the AS concentration or by adding 1 M NaCl or arginine. AS at high concentrations resulted in binding of BSA even to an ion-exchange column, Q-Sepharose, at pH 7.0. Thus, although moderate salt concentrations elute proteins from Blue-Sepharose or ion-exchange columns, proteins can be bound to these columns under extreme salting-out conditions. Similar enhanced binding of proteins by AS was observed with an ATP-affinity column.

  6. Aqueous two-phase extraction of 2,3-butanediol from fermentation broths by isopropanol/ammonium sulfate system. (United States)

    Sun, Li-Hui; Jiang, Bo; Xiu, Zhi-Long


    A novel aqueous two-phase system consisted of 2-propanol/ammonium sulfate was used for the extraction of 2,3-butanediol from fermentation broths. The maximum partition coefficient and recovery of 2,3-butanediol reached 9.9 and 93.7%, respectively, and more than 99% of the cells and about 85% of the soluble proteins were removed when 34% (w/w) 2-propanol and 20% (w/w) ammonium sulfate were used. The separated cells could be re-used as inocula for subsequent fermentations. The aqueous two-phase system described in this study may have potential application in the extraction of 2,3-butanediol produced by industrial fermentation processes.

  7. Distribution coefficients of purine alkaloids in water-ammonium sulfate-alkyl acetate-dialkyl phthalate systems (United States)

    Korenman, Ya. I.; Krivosheeva, O. A.; Mokshina, N. Ya.


    The distribution of purine alkaloids (caffeine, theobromine, theophylline) was studied in the systems: alkyl acetates-dialkyl phtalate-salting-out agent (ammonium sulfate). The quantitative characteristics of the extraction-distribution coefficients ( D) and the degree of extraction ( R, %) are calculated. The relationships between the distribution coefficients of alkaloids and the length of the hydrocarbon radical in the molecule of alkyl acetate (dialkyl phtalate) are determined. The possibility of predicting the distribution coefficients is demonstrated.

  8. Effects of Sodium Citrate on the Ammonium Sulfate Recycled Leaching of Low-Grade Zinc Oxide Ores (United States)

    Yang, Kun; Li, Shi-wei; Zhang, Li-bo; Peng, Jin-hui; Ma, Ai-yuan; Wang, Bao-bao


    The effects of sodium citrate on ammonium sulfate recycled leaching of low-grade zinc oxide ores were studied. By applying various kinds of detection and analysis techniques such as chemical composition analysis, chemical phase method, scanning electron microscopy and energy dispersive spectrum (SEM/EDS), X-ray diffraction (XRD) and Fourier-transforming infrared spectrum (FT-IR), zinc raw ore, its leaching slag and the functional mechanism of sodium citrate were investigated. Based on a comprehensive analysis, it can be concluded that in contrast to hemimorphite (Zn4Si2O7(OH)2 · H2O), amorphous smithsonite (ZnCO3) and zinc silicate (Zn2SiO4) prove to be refractory phases under ammonium sulfate leaching, while sodium citrate has a better chelating action with the refractory phases, resulting in a higher zinc leaching rate. Under conditions of [NH3]/[NH3]T molar ratio being 0.5, [NH3]T being 7.5 mol/L, [Na3C6H5O7] being 0.2 mol/L, S/L ratio being 1:5, temperature being 303 K, holding time being 1 h in each of the two stages, and stirring rate being 300 rpm, the leaching rate of zinc reached 93.4%. In this article, sulfate ammonium recycled technology also reveals its unique advantage in processing low-grade zinc oxide ores accompanied by high silicon and high alkaline gangue.

  9. Importance of including ammonium sulfate ((NH42SO4 aerosols for ice cloud parameterization in GCMs

    Directory of Open Access Journals (Sweden)

    R. Yang


    Full Text Available A common deficiency of many cloud-physics parameterizations including the NASA's microphysics of clouds with aerosol-cloud interactions (hereafter called McRAS-AC is that they simulate lesser (larger than the observed ice cloud particle number (size. A single column model (SCM of McRAS-AC physics of the GEOS4 Global Circulation Model (GCM together with an adiabatic parcel model (APM for ice-cloud nucleation (IN of aerosols were used to systematically examine the influence of introducing ammonium sulfate (NH42SO4 aerosols in McRAS-AC and its influence on the optical properties of both liquid and ice clouds. First an (NH42SO4 parameterization was included in the APM to assess its effect on clouds vis-à-vis that of the other aerosols. Subsequently, several evaluation tests were conducted over the ARM Southern Great Plain (SGP and thirteen other locations (sorted into pristine and polluted conditions distributed over marine and continental sites with the SCM. The statistics of the simulated cloud climatology were evaluated against the available ground and satellite data. The results showed that inclusion of (NH42SO4 into McRAS-AC of the SCM made a remarkable improvement in the simulated effective radius of ice cloud particulates. However, the corresponding ice-cloud optical thickness increased even more than the observed. This can be caused by lack of horizontal cloud advection not performed in the SCM. Adjusting the other tunable parameters such as precipitation efficiency can mitigate this deficiency. Inclusion of ice cloud particle splintering invoked empirically further reduced simulation biases. Overall, these changes make a substantial improvement in simulated cloud optical properties and cloud distribution particularly over the Intertropical Convergence Zone (ITCZ in the GCM.

  10. Identification and Characterization of Visible Absorption Components in Aqueous Methylglyoxal-Ammonium Sulfate Mixtures (United States)

    McGivern, W. S.; Allison, T. C.; Radney, J. G.; Zangmeister, C. D.


    The aqueous reaction of methylglyoxal (MG) with ammonium sulfate has been suggested as a source of atmospheric ``brown carbon.'' We have utilized high-performance liquid chromatography coupled to ultraviolet-visible spectroscopy and tandem mass spectrometry to study the products of this reaction at high concentrations. The overall product spectrum shows a large number of distinct components; however, the visible absorption from this mixture is derived a very small number of components. The largest contributor is an imine-substituted (C=N-H) product of aldol condensation/facile dehydration reaction between the parent MG and a hydrated product of the MG + ammonia reaction. The asymmetric nature of this compound relative to the aldol condensation of two MG results in a sufficiently large redshift of the UV absorption spectrum that absorption of visible radiation can occur in the long-wavelength tail. The simplicity of the imine products is a result of a strong bias toward ketimine products due to the extensive hydration of the aldehydic moiety in the parent in aqueous solution. In addition, a strong pH dependence of the absorption cross section was observed with significantly greater absorption under more basic conditions. We have performed time-dependent density functional theory calculations to evaluate the absorption spectra of all of the possible condensation products and their respective ions, and the results are consistent with the experimental observations. We have also observed smaller concentrations of other condensation products of the imine-substituted parent species that do not contribute significantly to the visible absorption but have not been previously discussed.

  11. Effects of the physical state of tropospheric ammonium-sulfate-nitrate particles on global aerosol direct radiative forcing

    Directory of Open Access Journals (Sweden)

    S. T. Martin


    Full Text Available The effect of aqueous versus crystalline sulfate-nitrate-ammonium tropospheric particles on global aerosol direct radiative forcing is assessed. A global three-dimensional chemical transport model predicts sulfate, nitrate, and ammonium aerosol mass. An aerosol thermodynamics model is called twice, once for the upper side (US and once for lower side (LS of the hysteresis loop of particle phase. On the LS, the sulfate mass budget is 40% solid ammonium sulfate, 12% letovicite, 11% ammonium bisulfate, and 37% aqueous. The LS nitrate mass budget is 26% solid ammonium nitrate, 7% aqueous, and 67% gas-phase nitric acid release due to increased volatility upon crystallization. The LS ammonium budget is 45% solid ammonium sulfate, 10% letovicite, 6% ammonium bisulfate, 4% ammonium nitrate, 7% ammonia release due to increased volatility, and 28% aqueous. LS aerosol water mass partitions as 22% effloresced to the gas-phase and 78% remaining as aerosol mass. The predicted US/LS global fields of aerosol mass are employed in a Mie scattering model to generate global US/LS aerosol optical properties, including scattering efficiency, single scattering albedo, and asymmetry parameter. Global annual average LS optical depth and mass scattering efficiency are, respectively, 0.023 and 10.7 m2  (g SO42−−1, which compare to US values of 0.030 and 13.9 m2 (g SO42−−1. Radiative transport is computed, first for a base case having no aerosol and then for the two global fields corresponding to the US and LS of the hysteresis loop. Regional, global, seasonal, and annual averages of top-of-the-atmosphere aerosol radiative forcing on the LS and US (FL and FU, respectively, in W m2− are calculated. Including both anthropogenic and natural emissions, we obtain global annual averages of FL = −0.750, FU = −0.930, and

  12. Simulations of Sulfate-Nitrate-Ammonium (SNA) aerosols during the extreme haze events over Northern China in 2014

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Dan; Liu, Zhiquan; Fast, Jerome D.; Ban, Junmei


    Extreme haze events have occurred frequently over China in recent years. Although many studies have investigated the formation mechanisms associated with PM2.5 for heavily polluted regions in China based on observational data, adequately predicting peak PM2.5 concentrations is still challenging for regional air quality models. In this study, we evaluate the performance of one configuration of the Weather Research and Forecasting model coupled with chemistry (WRF-Chem) and use the model to investigate the sensitivity of heterogeneous reactions on simulated peak sulfate, nitrate, and ammonium concentrations in the vicinity of Beijing during four extreme haze episodes in October 2014 over the North China Plain. The highest observed PM2.5 concentration of 469 μg m-3 occurred in Beijing. Comparisons with observations show that the model reproduced the temporal variability in PM2.5 with the highest PM2.5 values on polluted days (defined as days in which observed PM2.5 is greater than 75 μg m-3), but predictions of sulfate, nitrate, and ammonium were too low on days with the highest observed concentrations. Observational data indicate that the sulfur/nitric oxidation rates are strongly correlated with relative humidity during periods of peak PM2.5; however, the model failed to reproduce the highest PM2.5 concentrations due to missing heterogeneous reactions. As the parameterizations of those reactions is not well established yet, estimates of SO2-to-H2SO4 and NO2/NO3-to-HNO3 reaction rates that depend on relative humidity were applied which improved the simulation of sulfate, nitrate, and ammonium enhancement on polluted days in terms of both concentrations and partitioning among those species. Sensitivity simulations showed that the extremely high heterogeneous reaction rates and also higher emission rates than those reported in the emission inventory

  13. Simulations of sulfate-nitrate-ammonium (SNA) aerosols during the extreme haze events over northern China in October 2014 (United States)

    Chen, Dan; Liu, Zhiquan; Fast, Jerome; Ban, Junmei


    Extreme haze events have occurred frequently over China in recent years. Although many studies have investigated the formation mechanisms associated with PM2.5 for heavily polluted regions in China based on observational data, adequately predicting peak PM2.5 concentrations is still challenging for regional air quality models. In this study, we evaluate the performance of one configuration of the Weather Research and Forecasting model coupled with chemistry (WRF-Chem) and use the model to investigate the sensitivity of heterogeneous reactions on simulated peak sulfate, nitrate, and ammonium concentrations in the vicinity of Beijing during four extreme haze episodes in October 2014 over the North China Plain. The highest observed PM2.5 concentration of 469 µg m-3 occurred in Beijing. Comparisons with observations show that the model reproduced the temporal variability in PM2.5 with the highest PM2.5 values on polluted days (defined as days in which observed PM2.5 is greater than 75 µg m-3), but predictions of sulfate, nitrate, and ammonium were too low on days with the highest observed concentrations. Observational data indicate that the sulfur/nitric oxidation rates are strongly correlated with relative humidity during periods of peak PM2.5; however, the model failed to reproduce the highest PM2.5 concentrations due to missing heterogeneous/aqueous reactions. As the parameterizations of those heterogeneous reactions are not well established yet, estimates of SO2-to-H2SO4 and NO2/NO3-to-HNO3 reaction rates that depend on relative humidity were applied, which improved the simulation of sulfate, nitrate, and ammonium enhancement on polluted days in terms of both concentrations and partitioning among those species. Sensitivity simulations showed that the extremely high heterogeneous reaction rates and also higher emission rates than those reported in the emission inventory were likely important factors contributing to those peak PM2.5 concentrations.

  14. Evaluation of N sub 2 fixation by applying sup 15 N labeled plant material and ammonium sulfate

    Energy Technology Data Exchange (ETDEWEB)

    Chiu, C.Y.; Yoshida, T.


    Effect of different {sup 15}N labeled sources on the estimation of N{sub 2} fixation was investigated. The combination of {sup 15}N labeled ammonium sulfate, {sup 15}N labeled plant material, and {sup 15}N labeled ammonium sulfate with unlabeled plant material, was examined in pot experiments. Two cultivars of soybean (Glycine max) and one of mungbean (Vigna radiata) were used. No significant difference was observed among the treatments for the estimation of N{sub 2} fixation. This was due to the homogeneity and stability of the {sup 15}N abundance in soil which resulted in a similar N uptake from the soil by the N{sub 2} fixing and reference crops. The plant yield, total N uptake and amount of N{sub 2} fixed were higher in the Yellow Soil than in the Andosol. The amount of N{sub 2} fixed was strongly influenced by the plant growth and consequently it affected the plant yield. The slow decomposition of plant material in the Andosol resulted in a low yield in both the N{sub 2} fixing and reference crops. Thus, the artificial decrease of the available N content in soil, by application of plant material, did not stimulate N{sub 2} fixation but suppressed plant growth and N{sub 2} fixation.

  15. Second organic aerosol formation from the ozonolysis of α-pinene in the presence of dry submicron ammonium sulfate aerosol

    Institute of Scientific and Technical Information of China (English)

    ZHAO Zhe; HAO Jiming; LI Junhua; WU Shan


    An indoor chamber facility is described for investigation of atmospheric aerosol chemistry. Two sets of α-pinene ozonolysisexperiments were conducted in the presence of dry ammonium sulfate seed particle: ozone limited experiments and α-pinene limitedexperiments. The concentration of gas phase and particle phase species was monitored continuously by on-line instruments andrecorded automatically by data sampling system. The evolution of size distribution was measured by a scanning mobility particlesizer (SMPS), and α-pinene consumed was measured using GC-FID. Secondary organic aerosol (SOA) produced for seed-free systemis 100% organic in content, resulting from a sufficient supersaturation of low volatility organics to produce homogeneous nucleationfollowed by condensation to the aerosol. Secondary organic aerosol produced in seeded system is a mixture of organic and inorganicconstituents, initially forms via condensation onto the inorganic particles, and subsequent growth occurs via absorption into the organicsurface coating the inorganic core. Although the formation process and the size distribution for seed-free system and seeded system isdifferent, the ultimate mass of SOA formed is equal, and SOA yield for the two system located in the same regression line when usingone-product model, suggesting that the presence of dry ammonium sulfate seed has no measurable effect on the total aerosol yield, and the dry seed particle acts solely as a site upon which organic deposition occurs.

  16. Selectively leaching Cu(Ⅱ) and Ni(Ⅱ) from acid mine drainage sludge by using ethylenediamine-ammonium sulfate

    Institute of Scientific and Technical Information of China (English)


    A method based on controlling the complexation-precipitation equilibrium of metal ions was proposed to selectively recover nickel and copper from hydroxide sludge formed by lime neutralization of acid mine drainage(AMD). Ethylenediamine(EDA) and ammonium sulfate were chosen as complex reagent and precipitating reagent, respectively, to dissolve target metal hydroxides from sludge and limit useless metal ions in the pregnant solution. Results from both synthetic and natural samples show the excellent selectivity for the target metals(copper and nickel) against Fe(Ⅲ), Ca(Ⅱ) and Mg(Ⅱ), 99% recovery of Cu(Ⅱ) and Ni(Ⅱ) and shorter leaching time can be reached by this process, and the resultant solution can be used for direct electrowinning. The optimum operating conditions are: pH=9~11, ρ(EDA)=40g/L, ammonium sulfate 50g/L, leaching time 5h(for natural sample) and 2.5h(for synthetic sludge), liquid to solid ratio being 4 with mechanical stirring at room temperature.

  17. {sup 15}N-labeled nitrogen from green manure and ammonium sulfate utilization by the sugarcane ratoon

    Energy Technology Data Exchange (ETDEWEB)

    Ambrosano, Edmilson Jose; Rossi, Fabricio, E-mail: [Agencia Paulista de Tecnologia dos Agronegocios (APTA), Piracicapa, SP (Brazil). Polo Rigional Centro Sul; Trivelin, Paulo Cesar Ocheuze [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil). Lab. de Isotopos Estaveis; Cantarella, Heitor [Agencia Paulista de Tecnologia dos Agronegocios (APTA/IAC), Campinas, SP (Brazil). Instituto Agronomico de Campinas. Centro de Solos e Recursos Agroambientais; Ambrosano, Glaucia Maria Bovi [Universidade de Campinas (UNICAMP/FOP), Piracicaba, SP (Brazil). Fac. de Odontologia de Piracicaba. Dept. de Odontologia Social, Bioestatistica; Schammass, Eliana Aparecida [Agencia Paulista de Tecnologia dos Agronegocios (APTA/IZ), Nova Odessa, SP (Brazil). Instituto de Zootecnia; Muraoka, Takashi [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil). Lab. de Fertilidade do solo


    Legumes as green manure are alternative sources of nitrogen (N) for crops and can supplement or even replace mineral nitrogen fertilization due to their potential for biological nitrogen fixation (BNF). The utilization of nitrogen by sugarcane (Saccharum spp.) fertilized with sunn hemp (Crotalaria juncea L.) and ammonium sulfate (AS) was evaluated using the {sup 15}N tracer technique. N was added at the rate of 196 and 70 kg ha{sup -1} as {sup 15}N-labeled sunn hemp green manure (SH) and as ammonium sulfate (AS), respectively. Treatments were: (I) Control; (II) AS{sup 15}N; (III) SH{sup 15}N + AS; (IV) SH{sup 15}N; and (V) AS{sup 15}N + SH. Sugarcane was cultivated for five years and was harvested three times. {sup 15}N recovery was evaluated in the two first harvests. In the sum of the three harvests, the highest stalk yields were obtained with a combination of green manure and inorganic N fertilizer; however, in the second cutting the yields were higher where SH was used than in plots with AS. The recovery of N by the first two consecutive harvests accounted for 19 to 21% of the N applied as leguminous green manure and 46 to 49% of the N applied as AS. The amounts of inorganic N, derived from both N sources, present in the 0-0.4 m layer of soil in the first season after N application and were below 1 kg ha{sup -1}. (author)

  18. Life cycle energy and greenhouse gas profile of a process for the production of ammonium sulfate from nitrogen-fixing photosynthetic cyanobacteria. (United States)

    Razon, Luis F


    In this paper, an alternative means for nitrogen fixation that may consume less energy and release less greenhouse gases than the Haber-Bosch process is explored. A life-cycle assessment was conducted on a process to: culture the cyanobacterium, Anabaena sp. ATCC 33047, in open ponds; harvest the biomass and exopolysaccharides and convert these to biogas; strip and convert the ammonia from the biogas residue to ammonium sulfate; dry the ammonium sulfate solution to ammonium sulfate crystals and transport the finished product. The results suggest that substantial reductions in non-renewable energy use and greenhouse gas emissions may be realized. The study opens the possibility that Haber-Bosch ammonia may be replaced with ammonia from a biomass process which simultaneously generates renewable energy. The process is intrinsically safer than the Haber-Bosch process. However, there are trade-offs in terms of land use and possibly, water.

  19. Raman Spectra and Nucleation Rates of Sulfuric Acid and Ammonium Sulfate Aerosols Supercooled with Respect to Ice (United States)

    Knopf, D. A.; Koop, T.; Weers, U. G.; Krieger, U. K.; Peter, T.


    Sulfuric acid and ammonium sulfate aerosol particles can serve as ice condensation nuclei for the formation of upper tropospheric cirrus clouds. These clouds influence the global radiation budget by scattering of short wavelength (solar) radiation as well as by absorbing long wavelength (terrestrial) radiation. Knowledge of the thermodynamics and the nucleation rates of aerosols is fundamental for the understanding of formation processes of cirrus clouds. Here, we present a new investigation tool to observe phase transitions of aerosols supercooled with respect to ice. Confocal Raman microscopy is used to determine the phase changes and the morphology of the particles. Raman spectroscopy is employed to distinguish and to characterize the different phases inside the frozen particles. Single droplets with a diameter of typically 20-120 μ m are deposited on a hydrophobically coated Herasil-plate that is covered by a spacer and another plate. Since the gas phase volume of the cell is small compared to the liquid droplet volume the composition of the droplets remains fixed during temperature changes. The temperature of the droplets can be varied between 150-350~K. We present the first Raman spectra of aqueous H2SO4/H2O and (NH4)2SO4/H2O droplets for several concentrations and temperatures to the homogeneous ice nucleation limits. The analysis of the speciation of the components inside the droplets (e.g. sulfate vs. bisulfate ions) is compared to results from thermodynamic models. Evaluation of the freezing data gives upper limits for ice nucleation rates of droplets as a function of sulfuric acid or ammonium sulfate concentration.

  20. Sulfate-reducing anaerobic ammonium oxidation as a potential treatment method for high nitrogen-content wastewater. (United States)

    Rikmann, Ergo; Zekker, Ivar; Tomingas, Martin; Tenno, Taavo; Menert, Anne; Loorits, Liis; Tenno, Toomas


    After sulfate-reducing ammonium oxidation (SRAO) was first assumed in 2001, several works have been published describing this process in laboratory-scale bioreactors or occurring in the nature. In this paper, the SRAO process was performed using reject water as a substrate for microorganisms and a source of NH(4) (+), with SO(4) (2-) being added as an electron acceptor. At a moderate temperature of 20°C in a moving bed biofilm reactor (MBBR) sulfate reduction along with ammonium oxidation were established. In an upflow anaerobic sludge blanket reactor (UASBR) the SRAO process took place at 36°C. Average volumetric TN removal rates of 0.03 kg-N/m³/day in the MBBR and 0.04 kg-N/m³/day in the UASBR were achieved, with long-term moderate average removal efficiencies, respectively. Uncultured bacteria clone P4 and uncultured planctomycete clone Amx-PAn30 were detected from the biofilm of the MBBR, from sludge of the UASBR uncultured Verrucomicrobiales bacterium clone De2102 and Uncultured bacterium clone ATB-KS-1929 were found also. The stoichiometrical ratio of NH(4) (+) removal was significantly higher than could be expected from the extent of SO(4) (2-) reduction. This phenomenon can primarily be attributed to complex interactions between nitrogen and sulfur compounds and organic matter present in the wastewater. The high NH(4) (+) removal ratio can be attributed to sulfur-utilizing denitrification/denitritation providing the evidence that SRAO is occurring independently and is not a result of sulfate reduction and anammox. HCO(3) (-) concentrations exceeding 1,000 mg/l were found to have an inhibiting effect on the SRAO process. Small amounts of hydrazine were naturally present in the reaction medium, indicating occurrence of the anammox process. Injections of anammox intermediates, hydrazine and hydroxylamine, had a positive effect on SRAO process performance, particularly in the case of the UASBR.

  1. [Serodiagnosis of schistosomiasis mansoni using an egg extract semi-purified by precipitation with ammonium sulfate]. (United States)

    Ouattara, S A; Sauneron, M F; Tribouley-Duret, J; Tribouley, J


    Fifty one sera from bilharziosis patients and thirty control sera were examined with a Schistosoma mansoni egg antigen purified by precipitation with ammonium sulphate at 50% saturation. Sensitivity and specificity were good and showed a good correlation with results obtained by MSA1 antigen, but antigen tested is far more easier to prepare than MSA1.

  2. Partition of Chiral pharmaceutical intermediate R(-)-Mandelic Acid in Aqueous Two-Phase System of Poly(ethylene glycol)-Ammonium Sulfate

    Institute of Scientific and Technical Information of China (English)

    Xu Xiaoping; Li Zhongqin; Chen Jiebo; Huang Xinghua


    An aqueous two-phase system of poly (ethylene glycol)-ammonium sulfate was employed to separate R (-)-mandelic acid.The result showed that R (-)-mandelic acid has priority to partition in PEG-rich top phase. This indicated that aqueous two-phase is a very suitable system for separation of R(-)-mandelic acid.

  3. Crystal structure of bis-(di-methyl-ammonium) hexa-aqua-nickel(II) bis-(sulfate) dihydrate. (United States)

    Held, Peter


    In the title salt, (C2H8N)2[Ni(H2O)6)](SO4)2·2H2O, the Ni(II) cation is located on a centre of inversion and exhibits a slightly distorted octa-hedral arrangement of water mol-ecules. The Ni-O bond lengths in the complex [Ni(H2O)6](2+) cation show a distribution as in the related Tutton salt (NH4)2[Ni(H2O)6](SO4)2, but are longer in average [2.056 (13) versus 2.037 (12) Å]. The noncoordinating water mol-ecules and di-methyl-ammonium cations connect the sulfate and [Ni(H2O)6](2+) octa-hedra via O-H⋯O and N-H⋯O hydrogen bonds from weak up to medium strength into a three-dimensional framework whereby the complex metal cations and sulfate anions are arranged in sheets parallel (001).

  4. Process for Production of Potassium Sulfate with Potassium Chloride-Ammonium Sulfate Conversion Method%氯化钾-硫酸铵转化法制硫酸钾生产工艺

    Institute of Scientific and Technical Information of China (English)

    赵玉平; 周丽; 李元峰; 靖美萍


    简要介绍了氯化钾-硫酸铵转化法制硫酸钾生产工艺及关键设备。该工艺的主产品硫酸钾及副产品氯化铵钾均可在企业内部消化,不仅可优化产品组合,而且降低了外部市场波动对企业经济效益的影响。%The production process and key equipment for production of potassium sulfate with potassium chloride-ammonium sulfate conversion method are briefly introduced.By this process, the main product potassium sulfate and the byproduct potassium ammonium chloride can be digested in the enterprise, it can not only optimize the product structure, but also reduce the influence of external market fluctuations on economic benefits of the enterprise.

  5. Crystal structure of bis-(di-methyl-ammonium) hexa-aqua-cobalt(II) bis-(sulfate) dihydrate. (United States)

    Held, Peter


    The title salt, (C2H8N)2[Co(H2O)6)](SO4)2·2H2O, is isotypic with (C2H8N)2[Ni(H2O)6)](SO4)2·2H2O. The Co-O bond lengths in the [Co(H2O)6](2+) complex cation show very similar distances as in the related Tutton salt (NH4)2[Co(H2O)6)](SO4)2 [average 2.093 (17) Å], but are significantly longer than in the isotypic Ni(II) compound (Δd ≃ 0.04 Å). The cobalt cation reaches an overall bond-valence sum of 1.97 valence units. The S-O distances are nearly equal, ranging from 1.454 (4) to 1.470 (3) Å [mean 1.465 (12) Å]; however, the O-S-O angles vary clearly from 108.1 (2) to 110.2 (2)° [average bond angle 109.5 (9)°]. The non-coordinating water mol-ecules and di-methyl-ammonium cations connect the sulfate tetrahedra and the [Co(H2O)6](2+) octa-hedron via O-H⋯O and N-H⋯O hydrogen bonds of weak up to medium strength into a three-dimensional framework whereby the complex metal cations and sulfate anions are arranged in sheets parallel to (001).

  6. Determination of standard enthalpies of formation and lattice energies of ammonium chloride and ammonium sulfate%氯化铵和硫酸铵生成焓与晶格能测定

    Institute of Scientific and Technical Information of China (English)

    杨春; 成文玉; 王庆伦; 刘晓莉; 王桂香; 杨津


    A new inorganic chemistry experiment of “Determination of standard enthalpies of formation and lattice energies of ammonium chloride and ammonium sulfate” has been designed . To reduce the measurement error , temperature was measured by digital Beckman thermometer and the experimental data were passed to computer for drawing and linear regress by means of software Origin . As a result , the mass of ammonium chloride used for measurement of enthalpy of dissolution decreased to about 40% .The designing experiment on ammonium sulfate can cultivate the integrated ability of students .Calculations of the lattice energies of ammonium chloride and ammonium sulfate based on their enthalpies of dissolution are introduced ,which can guide the students to research the relationship between the ionic crystal structures and physicochemical properties .%设计改进了一个新的无机化学实验“氯化铵和硫酸铵生成焓与晶格能的测定”。用数字贝克曼温度计代替水银温度计以减小测量的误差;用作图法对温度-时间曲线进行校正,提高了温度测量的准确度;在测定N H4 C1溶解焓的实验中使N H4 C1的用量减少为原来的40%,硫酸铵的设计性实验可以培养学生的综合能力,所得硫酸铵溶液可用作制备硫酸亚铁铵的原料;通过溶解热求晶格能,引导学生探究离子晶体结构与物性间的关系。

  7. Cryo-transmission electron microscopy imaging of the morphology of submicrometer aerosol containing organic acids and ammonium sulfate. (United States)

    Veghte, Daniel P; Bittner, Danielle Rae; Freedman, Miriam Arak


    The effects of aerosol particles on heterogeneous atmospheric chemistry and climate are determined in part by the internal arrangement of compounds within the particles. To characterize the morphology of internally mixed aerosol particles in the accumulation mode size regime, we have used cryo-transmission electron microscopy to investigate the phase separation behavior of dry, submicrometer particles composed of ammonium sulfate mixed with carboxylic acids (adipic, azelaic, citric, glutaric, malonic, pimelic, suberic, and succinic acid). Determining the morphology of dry particles is important for understanding laboratory studies of aerosol optical properties, reactivity, and cloud condensation nucleus activity, results from field instruments where aerosol particles are dried prior to analysis, and atmospheric processes like deposition mode heterogeneous ice nucleation that occur on dried particles. We observe homogeneous morphologies for highly soluble organic compounds. For organic compounds with limited aqueous solubility, partially engulfed structures are observed. At intermediate aqueous solubilities, small particles are homogeneous and larger particles are partially engulfed. Results are compared to previous studies of liquid-liquid phase separation in supermicrometer particles and the impact of these dry particle morphologies on aerosol-climate interactions are discussed.

  8. Parameterization of N2O5 reaction probabilities on the surface of particles containing ammonium, sulfate, and nitrate

    Directory of Open Access Journals (Sweden)

    K. M. Foley


    Full Text Available A comprehensive parameterization was developed for the heterogeneous reaction probability (γ of N2O5 as a function of temperature, relative humidity, particle composition, and phase state, for use in advanced air quality models. The reaction probabilities on aqueous NH4HSO4, (NH42SO4, and NH4NO3 were modeled statistically using data and uncertainty values compiled from seven different laboratory studies. A separate regression model was fit to laboratory data for dry NH4HSO4 and (NH42SO4 particles, yielding lower γ values than the corresponding aqueous parameterizations. The regression equations reproduced 79% of the laboratory data within a factor of two and 53% within a factor of 1.25. A fixed value was selected for γ on ice-containing particles based on a review of the literature. The combined parameterization was applied under atmospheric conditions representative of the eastern United States using 3-dimensional fields of temperature, relative humidity, sulfate, nitrate, and ammonium, obtained from a recent Community Multiscale Air Quality model simulation. The resulting spatial distributions of γ were contrasted with three other parameterizations that have been applied in air quality models in the past and with atmospheric observational determinations of γ. Our results highlight a critical need for more laboratory measurements of γ at low temperature and high relative humidity to improve model simulations of N2O5 hydrolysis during wintertime conditions.

  9. Experimental additions of aluminum sulfate and ammonium nitrate to in situ mesocosms to reduce cyanobacterial biovolume and microcystin concentration (United States)

    Harris, Ted D.; Wilhelm, Frank M.; Graham, Jennifer L.; Loftin, Keith A.


    Recent studies suggest that nitrogen additions to increase the total nitrogen:total phosphorus (TN:TP) ratio may reduce cyanobacterial biovolume and microcystin concentration in reservoirs. In systems where TP is >100 μg/L, however, nitrogen additions to increase the TN:TP ratio could cause ammonia, nitrate, or nitrite toxicity to terrestrial and aquatic organisms. Reducing phosphorus via aluminum sulfate (alum) may be needed prior to nitrogen additions aimed at increasing the TN:TP ratio. We experimentally tested this sequential management approach in large in situ mesocosms (70.7 m3) to examine effects on cyanobacteria and microcystin concentration. Because alum removes nutrients and most seston from the water column, alum treatment reduced both TN and TP, leaving post-treatment TN:TP ratios similar to pre-treatment ratios. Cyanobacterial biovolume was reduced after alum addition, but the percent composition (i.e., relative) cyanobacterial abundance remained unchanged. A single ammonium nitrate (nitrogen) addition increased the TN:TP ratio 7-fold. After the TN:TP ratio was >50 (by weight), cyanobacterial biovolume and abundance were reduced, and chrysophyte and cryptophyte biovolume and abundance increased compared to the alum treatment. Microcystin was not detectable until the TN:TP ratio was microcystin concentrations in high-phosphorus systems. Additional studies are needed to define best management practices before combined alum and nitrogen additions are implemented as a reservoir management strategy.

  10. Energy-Saving Study of a System for Ammonium Sulfate Recovery from Wastewater with Mechanical Vapor Compression (MVC

    Directory of Open Access Journals (Sweden)

    Lin Liang


    Full Text Available In this study, a new two stage Mechanical Vapor Compression (MVC system which is used to recycle ammonium sulfate is investigated. In evaporation process, there are many efficient ways such as multiple-effect evaporation, multi-stage flash, thermal vapor compression, and mechanical vapor compression and so on. In these ways MVC is considered to be more effective. Now, almost all of the MVC systems in the literatures are about one stage structure. However, in the other process such as continuous crystallizer, if one stage MVC system is adopted, a lot of energy will be wasted. Therefore, in order to further save energy, a new system should be proposed. In this study, a new two stage MVC system is proposed and analyzed using the software of ASPEN PLUS. The first stage is a forcible recycle evaporator with MVC and the second one is a forcible recycle crystallizer with MVC. The energy consumption is discussed as a function of the middle concentration and the operating temperature. The results show that the compressor power decreases with the increase in the operating temperature and the optimal compressor power is obtained when the mass concentration is about 32%. Compared with one stage MVC system the running cost of the new system can be saved 29.2% and more than 25.8% of the energy can be saved. Additionally, it can save running cost over 42.2% and save energy more than 59.6% compared with the conventional multi-effect system.

  11. The effect of ammonium sulfate on the solubility of amino acids in water at (298.15 and 323.15) K

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Luisa A.; Macedo, Eugenia A. [Laboratory of Separation and Reaction Engineering, Departamento de Engenharia Quimica, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto (Portugal); Pinho, Simao P. [Laboratory of Separation and Reaction Engineering, Departamento de Tecnologia Quimica e Biologica, Instituto Politecnico de Braganca, Campus e Santa Apolonia, 5301-857 Braganca (Portugal)], E-mail:


    Using the analytical gravimetric method the solubility of glycine, DL-alanine, L-isoleucine, L-threonine, and L-serine in aqueous systems of (NH{sub 4}){sub 2}SO{sub 4}, at (298.15 and 323.15) K, were measured for salt concentrations ranging up to 2.0 molal. In the electrolyte molality range studied the experimental observations showed that ammonium sulfate is a salting-in agent for most of the amino acids studied. Furthermore, the change of the relative solubility with electrolyte concentration shows a maximum, which makes the representation of the data by a simple empirical correlation such as the Setschenow equation difficult. For the development and evaluation of a robust thermodynamic framework that makes it possible to more profoundly understand aqueous amino acid solutions with ammonium sulfate additional experimental information is needed.

  12. Optimization of Ammonium Sulfate Concentration for Purification of Colorectal Cancer Vaccine Candidate Recombinant Protein GA733-FcK Isolated from Plants. (United States)

    Park, Se-Ra; Lim, Chae-Yeon; Kim, Deuk-Su; Ko, Kisung


    A protein purification procedure is required to obtain high-value recombinant injectable vaccine proteins produced in plants as a bioreactor. However, existing purification procedures for plant-derived recombinant proteins are often not optimized and are inefficient, with low recovery rates. In our previous study, we used 25-30% ammonium sulfate to precipitate total soluble proteins (TSPs) in purification process for recombinant proteins from plant leaf biomass which has not been optimized. Thus, the objective in this study is to optimize the conditions for plant-derived protein purification procedures. Various ammonium sulfate concentrations (15-80%) were compared to determine their effects on TSPs yield. With 50% ammonium sulfate, the yield of precipitated TSP was the highest, and that of the plant-derived colorectal cancer-specific surface glycoprotein GA733 fused to the Fc fragment of human IgG tagged with endoplasmic reticulum retention signal KDEL (GA733(P)-FcK) protein significantly increased 1.8-fold. SDS-PAGE analysis showed that the purity of GA733(P)-FcK protein band appeared to be similar to that of an equal dose of mammalian-derived GA733-Fc (GA733(M)-Fc). The binding activity of purified GA733(P)-FcK to anti-GA733 mAb was as efficient as the native GA733(M)-Fc. Thus, the purification process was effectively optimized for obtaining a high yield of plant-derived antigenic protein with good quality. In conclusion, the purification recovery rate of large quantities of recombinant protein from plant expression systems can be enhanced via optimization of ammonium sulfate concentration during downstream processes, thereby offering a promising solution for production of recombinant GA733-Fc protein in plants.

  13. The use of a polymer inclusion membrane as a sorbent for online preconcentration in the flow injection determination of thiocyanate impurity in ammonium sulfate fertilizer. (United States)

    Ohshima, Takumi; Kagaya, Shigehiro; Gemmei-Ide, Makoto; Cattrall, Robert W; Kolev, Spas D


    A polymer inclusion membrane (PIM) is used for the first time as a sorbent in the construction of a preconcentration column to enhance the sensitivity in flow injection analysis (FIA). The PIM-coated column is readily prepared by coating the PIM containing poly(vinyl chloride), Aliquat 336, and 1-tetradecanol onto glass beads packed in a glass tube. The determination of trace amounts of thiocyanate in ammonium sulfate fertilizer demonstrates the potential of the proposed PIM-coated column in FIA. Thiocyanate standards or samples of relatively large volume (e.g. up to 2000 µL) are injected into a nitrate carrier stream. The sample zone passes through the proposed preconcentration column where thiocyanate is concentrated in a smaller volume of a carrier solution thus resulting in up to 7.4 fold increase in sensitivity. Thiocyanate is detected spectrophotometrically after its reaction with Fe(III) downstream of the preconcentration column. The limits of detection of thiocyanate in the absence and presence of 20 g L(-1) ammonium sulfate (S/N=2) are 0.014 and 0.024 mg L(-1), respectively. Thiocyanate was successfully determined in several samples of ammonium sulfate fertilizer.

  14. 磷石膏-碳铵-氨水球磨制备硫酸铵和碳酸钙%Ammonium Sulfate and Calcium Carbonate Prepared by Ball-milling from Phosphogypsum-Ammonium Bicarbonate-Ammonia Water

    Institute of Scientific and Technical Information of China (English)

    李娜; 邓跃全; 董发勤; 罗绍东; 李珊珊; 彭宝瑶


    Ammonium sulfate and calcium carbonate were prepared using phosphogypsum, ammonium bicarbonate and ammonia water as raw materials by ball-milling technique. The optimum conditions were explored through orthogonal test, the major elements and phase composition of two kinds of products were analyzed by XRF and XRD, and the grain size distribution and poisonous elements of calcium carbonate were determined using laser particle size analyzer and ICP. The analysis results showed that the optimum technological conditions were as follows: the liquid-solid ratio was 0.5, the response time was 45 min, the ball-material ratio was 3:1, rotational speed was 600 r/min, and the average conversion reaction was up to 97.95%; the product quality of ammonium sulfate reached the standard of byproduct ammonium sulfate, poisonous and harmful elements contents of calcium carbonate were far lower than quality criteria of soil environment allows. Preparation of ammonium sulfate and calcium carbonate from phosphogypsum by ball-milling achieved the purpose of effectively using phosphogypsum.%  以磷石膏、碳酸氢铵和氨水为原料,采用球磨工艺制备硫酸铵和碳酸钙.通过正交试验设计,探索磷石膏球磨制备硫酸铵和碳酸钙的最佳工艺条件,采用 XRF 和 XRD 分析了2种产物的化学组成及物相组成,采用激光粒度仪和 ICP 分别测定了碳酸钙的粒度分布及有毒有害元素含量.结果表明,球磨制备硫酸铵和碳酸钙适宜的工艺条件为:液固比0.5,反应时间45 min,球料比3∶1,转速600 r/min,反应的平均转化率达97.95%;硫酸铵产品质量达到了副产硫酸铵标准,碳酸钙中有毒有害元素的含量远低于土壤环境质量标准要求.磷石膏球磨制备硫酸铵和碳酸钙,实现了磷石膏的高效利用.

  15. 磷石膏转化制硫酸铵的发展前景分析%Development prospect of preparation of ammonium sulfate from phosphogypsum

    Institute of Scientific and Technical Information of China (English)

    赵建国; 张应虎; 张宗凡; 孙文中; 张峻; 陈树林


    分析指出硫酸铵产品在中国肥料、工业及出口应用领域均存在持续增长的消费空间;传统产业及烟气脱硫副产硫酸铵产能的增长难于满足消费增长的需要;磷石膏转化制硫酸铵具有产能扩展空间大的优势;国内磷石膏转化制硫酸铵的产业化技术基本成熟,副产碳酸钙渣的较佳用途是作酸性土壤改良剂.定量分析了产品售价对项目可接受氨价及需补贴资金的影响,给出了有补贴和无补贴资金时使项目经济可行的产品售价.指出磷石膏转化制硫酸铵在有条件的高浓磷复肥企业会有较好的发展前景.%Ammonium sulfate products have a sustainedly growing consumption space in China's fertilizer,industry,and export application fields.The ammonium sulfate's capacity growth of traditional industry and of by-product of flue gas desulfurization is difficult to meet the requirement of consumption growth.Preparation of ammonium sulfate from phosphogypsum has the advantage of wider capacity increasing space.The domestic industrial preparation technology of ammonium sulfate from phosphogypsum is mature,and the better use of its by-product calcium carbonate slag is to be the acidic soil improver.The influence of product sales price on the project acceptable ammonia price and on required capital subsidy is quantitatively analyzed,and the project economically viable sales prices with and without capital subsidy are given.It is also pointed out that the preparation of ammonium sulfate from phosphogypsum will have a good development prospect in some conditional enter prises of high-concentration phosphoric compound fertilizer.

  16. Formation mechanisms of channels on Titan through dissolution by ammonium sulfate and erosion by liquid ammonia and ethane (United States)

    Gilliam, Ashley E.; Lerman, Abraham


    Data obtained from the Cassini Visual and Infrared Mapping Spectrometer (VIMS), Imaging Science Subsystem (ISS), and Synthetic Aperture Radar (SAR) instruments have revealed an array of fluvial channels on Titan's surface, often several hundreds of kilometers in length. The paucity of impact craters on Titan's surface suggests a formation by fluvial erosion into the water-ice bedrock. Additionally, at the landing site, the Huygens Probe Descent Imager and Spectral Radiometer (DISR) imaged Earth-like rounded cobbles 0.3-15 cm in diameter composed of water ice, reminiscent of rounded stream clasts on Earth. In this paper we examine different fluvial features on Titan, identified by the Cassini spacecraft, and evaluate the possibilities of channel formation by dissolution of ice by a concentrated solution of ammonium sulfate, and by mechanical erosion by flow of liquid ammonia and liquid ethane. We find that chemical erosion of Titan's channels could be completed in 280 to 1100 years (all units of time in this paper are Terrestrial, not Titanian), much shorter than the period of about 84,000 years that a concentrated (NH4)2SO4-H2O solution could exist as a liquid on the Titan surface. Mechanical erosion of Titan's channels is generally a much slower process, on the order of 102 to 105 years to completion, and is also slower than mechanical erosion of a model river on Earth, averaging 103 to 104 years. The erosional sequence of the channels on Titan may have started after the formation of water-ice on the surface by the process of chemical dissolution by (NH4)2SO4-H2O, overlapping, or followed by, a period of mechanical erosion by liquid NH3. A final stage on the cooling surface of Titan might have been characterized by liquid C2H6 as an agent of mechanical erosion.

  17. Discussion on MET ammonium sulfate WFGD technology%MET湿式氨-硫酸铵法烟气脱硫技术研究

    Institute of Scientific and Technical Information of China (English)

    柯昌华; 陈捷


    The MET patented ammonium sulfate wet flue gas desulfurization technology is described. And the methods of control ing ammonium sulfite oxidation, ammonia slip, aerosols, chloride concentration and fly ash concentration in the slurry are presented further. MET ammonium sulfate FGD technology is an advanced tech-nology with the characteristics of mature, high SO2 removal efficiency, high reliability, simple operation and high value by-product.%简要介绍了MET氨法烟气脱硫技术,着重介绍了MET氨法对亚硫酸铵的氧化、氨逃逸、气溶胶、浆液中氯离子浓度和飞灰浓度等的控制措施。研究表明,MET氨法烟气脱硫技术是一种技术成熟、脱硫效率高、运行可靠、操作简单、副产物品质高的先进烟气脱硫技术。

  18. Research of the Acidizing of Ammonium Sulfate Decomposition of Phosphate Rock%酸化硫酸铵分解磷矿研究

    Institute of Scientific and Technical Information of China (English)

    赵新菊; 李沪萍; 罗康碧; 秦令; 苏毅


    磷石膏复分解可制备硫酸铵,硫酸铵应用于磷矿分解系统可使磷钙分离简单,从而可实现磷化工企业湿法硫循环利用的目的。本研究开展了热力学分析探讨酸化硫酸铵分解磷矿的可行性,采用正交实验考察了酸化硫酸铵的酸化剂类型、H+浓度、反应温度和时间对磷矿转化率的影响,对分解滤渣进行了表征。结果表明,酸化硫酸铵分解磷矿可行,硝酸和盐酸为酸化剂的分解效果最好,硫酸和磷酸为酸化剂的效果较差,这主要是受分解过程中硫酸钙结晶的影响。正交实验的最佳方案为:酸化剂盐酸,反应时间80 min,反应温度80℃,H+浓度5.4 mol/L,磷矿最终转化率达99.89%。%Ammonium sulfate can be prepared from the phosphogypsum by the metathetical reaction, and is used for decomposition of phosphate to make separation of calcium and phosphorus simple, which can achieve the purpose of the use of wet sulfur recycling for the phosphorus chemical enterprises. To achieve this goal, this paper investigated the feasibility of acidifying ammonium sulfate to decompose phosphate by thermodynamic analysis, using orthogonal experiment to investigate the effects of types of ammonium sulfate acidiifers, concentration of H+, reaction temperature and time on the conversion rate of phosphate, and residues were characterized. The results indicate that decomposing phosphate ore through ammonium sulfate acidiifcation is feasible, the effect of nitric acid and hydrochloric acid as decomposition acidiifers are best, and sulfuric acid and phosphoric acid appear relatively poor effect, which is mainly due to the crystallization of calcium sulfate in decomposition process. The best solution for the orthogonal experiments:hydrochloric acid as an acidifying agent, reaction time 80 min, reaction temperature 80℃, H+concentration 5.4 mol/L, phosphate ifnal conversion rate can reach 99.89%.

  19. Salting-out extraction of allicin from garlic (Allium sativum L.) based on ethanol/ammonium sulfate in laboratory and pilot scale. (United States)

    Li, Fenfang; Li, Qiao; Wu, Shuanggen; Tan, Zhijian


    Salting-out extraction (SOE) based on lower molecular organic solvent and inorganic salt was considered as a good substitute for conventional polymers aqueous two-phase extraction (ATPE) used for the extraction of some bioactive compounds from natural plants resources. In this study, the ethanol/ammonium sulfate was screened as the optimal SOE system for the extraction and preliminary purification of allicin from garlic. Response surface methodology (RSM) was developed to optimize the major conditions. The maximum extraction efficiency of 94.17% was obtained at the optimized conditions for routine use: 23% (w/w) ethanol concentration and 24% (w/w) salt concentration, 31g/L loaded sample at 25°C with pH being not adjusted. The extraction efficiency had no obvious decrease after amplification of the extraction. This ethanol/ammonium sulfate SOE is much simpler, cheaper, and effective, which has the potentiality of scale-up production for the extraction and purification of other compounds from plant resources.

  20. Development of an on-line source-tagged model for sulfate, nitrate and ammonium: A modeling study for highly polluted periods in Shanghai, China. (United States)

    Wu, Jian-Bin; Wang, Zifa; Wang, Qian; Li, Jie; Xu, Jianming; Chen, HuanSheng; Ge, Baozhu; Zhou, Guangqiang; Chang, Luyu


    An on-line source-tagged model coupled with an air quality model (Nested Air Quality Prediction Model System, NAQPMS) was applied to estimate source contributions of primary and secondary sulfate, nitrate and ammonium (SNA) during a representative winter period in Shanghai. This source-tagged model system could simultaneously track spatial and temporal sources of SNA, which were apportioned to their respective primary precursors in a simulation run. The results indicate that in the study period, local emissions in Shanghai accounted for over 20% of SNA contributions and that Jiangsu and Shandong were the two major non-local sources. In particular, non-local emissions had higher contributions during recorded pollution periods. This suggests that the transportation of pollutants plays a key role in air pollution in Shanghai. The temporal contributions show that the emissions from the "current day" (emission contribution from the current day during which the model was simulating) contributed 60%-70% of the sulfate and ammonium concentrations but only 10%-20% of the nitrate concentration, while the previous days' contributions increased during the recorded pollution periods. Emissions that were released within three days contributed over 85% averagely for SNA in January 2013. To evaluate the source-tagged model system, the results were compared by sensitivity analysis (emission perturbation of -30%) and backward trajectory analysis. The consistency of the comparison results indicated that the source-tagged model system can track sources of SNA with reasonable accuracy.

  1. Study on treatment of phenolic compounds in cokery wastewater by propyl-alcohol ammonium sulfate aqueous two-phase system%醇-盐双水相技术去除废水中的酚类物质

    Institute of Scientific and Technical Information of China (English)

    曹文; 高云涛; 王红斌; 李孔明; 马存娇


    A novel method for treatment of phenolic compounds in cokery wastewater by propyl-alcohol ammonium sulfate aqueous two-phase system was investigted.The effects of the amount of ammonium sulfate used,the amount of propyl-alcohol used,pH value on extractield was studied.Extraction was optimized using a L9(34)orthogonal test.The results indicated optimum extraction conditions were the amount of ammonium sulfate used of 18.0 g,the amount of propyl-alcohol used of 16 mL,and pH value of 3.0.A extraction yield of 99.37% was achived under optimum extraction conditions and via secondary extraction.

  2. Fine-tuning key parameters of an integrated reactor system for the simultaneous removal of COD, sulfate and ammonium and elemental sulfur reclamation

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Ye, E-mail: [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China); Chen, Chuan, E-mail: [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China); Liang, Bin, E-mail: [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China); Huang, Cong, E-mail: [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China); Zhao, Youkang, E-mail: [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China); Xu, Xijun, E-mail: [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China); Tan, Wenbo, E-mail: [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China); Zhou, Xu, E-mail: [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China); Gao, Shuang, E-mail: [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China); Sun, Dezhi, E-mail: [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China); Lee, DuuJong, E-mail: [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China); Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan (China); and others


    Graphical abstract: - Highlights: • The system achieved simultaneous removal of 98% COD, 98% sulfate and 78% nitrogen. • The HRTs and reflux ratios were key parameters for performance and S{sup 0} recovery. • 60% S{sup 0} reclaimed from effluent, 30% deposited in reactor S{sup 0} (S{sup 0} production ≈ 90%). • Characteristics of bio-S{sup 0} were targeted to acquire high-rate S{sup 0} recovery. • Microbial community succession and function were discussed at different stage. - Abstract: In this paper, we proposed an integrated reactor system for simultaneous removal of COD, sulfate and ammonium (integrated C-S-N removal system) and investigated the key parameters of the system for a high level of elemental sulfur (S{sup 0}) production. The system consisted of 4 main units: sulfate reduction and organic carbon removal (SR-CR), autotrophic and heterotrophic denitrifying sulfide removal (A and H-DSR), sulfur reclamation (SR), and aerated filter for aerobic nitrification (AN). In the system, the effects of key operational parameters on production of elemental sulfur were investigated, including hydraulic retention time (HRT) of each unit, sulfide/nitrate (S{sup 2−}-S/NO{sub 3}{sup −}-N) ratios, reflux ratios between the A and H-DSR and AN units, and loading rates of chemical oxygen demand (COD), sulfate and ammonium. Physico-chemical characteristics of biosulfur were studied for acquiring efficient S{sup 0} recovery. The experiments successfully explored the optimum parameters for each unit and demonstrated 98% COD, 98% sulfate and 78% nitrogen removal efficiency. The optimum HRTs for SR-CR, A and H-DSR and AN were 12 h, 3 h and 3 h, respectively. The reflux ratio of 3 could provide adequate S{sup 2−}-S/NO{sub 3}{sup −}-N ratio (approximately 1:1) to the A and H-DSR unit for obtaining maximum sulfur production. In this system, the maximum production of S{sup 0} reached 90%, but only 60% S{sup 0} was reclaimed from effluent. The S{sup 0} that adhered

  3. The effects of fuel composition and ammonium sulfate addition on PCDD, PCDF, PCN and PCB concentrations during the combustion of biomass and paper production residuals. (United States)

    Lundin, Lisa; Jansson, Stina


    The use of waste wood as an energy carrier has increased during the last decade. However, the higher levels of alkali metals and chlorine in waste wood compared to virgin biomass can promote the formation of deposits and organic pollutants. Here, the effect of fuel composition and the inhibitory effects of ammonium sulfate, (NH4)2SO4, on the concentrations of persistent organic pollutants (POPs) in the flue gas of a lab-scale combustor was investigated. Ammonium sulfate is often used as a corrosion-preventing additive and may also inhibit formation of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs). In addition to PCDDs and PCDFs, polychlorinated naphthalenes (PCN) and biphenyls (PCB) were also analyzed. It was found that the flue gas composition changed dramatically when (NH4)2SO4 was added: CO, SO2, and NH3 levels increased, while those of HCl decreased to almost zero. However, the additive's effects on POP formation were less pronounced. When (NH4)2SO4 was added to give an S:Cl ratio of 3, only the PCDF concentration was reduced, indicating that this ratio was not sufficient to achieve a general reduction in POP emissions. Conversely, at an S:Cl ratio of 6, significant reductions in the WHO-TEQ value and the PCDD and PCDF contents of the flue gas were observed. The effect on the PCDF concentration was especially pronounced. PCN formation seemed to be promoted by the elevated CO concentrations caused by adding (NH4)2SO4.

  4. 空气氧化—氨浸出废旧电路板中的铜%Ammonia-Ammonium Sulfate Copper Leaching from Waste Printed Circuit Boards

    Institute of Scientific and Technical Information of China (English)

    张有新; 李静; 潘发芳


    A novel hydrometallurgical process of copper recovery from waste printed circuit boards was introduced. In this process, air was blown into solution as oxidant for copper leaching in NH3-(NH4)2SO4-H2O system, while leaching residue was treated by physical method. The effects of ammonia and ammonium sulfate concentration, ratio of solid to liquid, leaching temperature, air flow and leaching time on copper leaching rate were investigated. The results show that copper leaching rate is up to 96. 67% under the following optimum conditions including ammonia concentration of 2 mol/L, ammonium sulfate concentration of 2 mol/L, ratio of solid to liquid of 1 : 20, leaching temperature of 25 ℃ , air flow of 8 m3/h and leaching time of 4 h.%提出了在氨水—硫酸铵体系下鼓入空气浸出废旧电路板中铜的新工艺.考察了氨水浓度、硫酸铵浓度、固液比、反应温度、通入空气流量和浸出时间对铜浸出率的影响.结果表明,在下述最佳浸出条件下,渣计铜浸出率达到96.67%:氨水浓度2 mol/L,硫酸铵浓度2 mol/L,固液比1∶20,反应温度25℃、通入空气量8 m3/h、浸出时间4h.

  5. Extraction and separation of tungsten (VI) from aqueous media with Triton X-100-ammonium sulfate-water aqueous two-phase system without any extractant. (United States)

    Yongqiang Zhang; Tichang Sun; Tieqiang Lu; Chunhuan Yan


    An aqueous two-phase system composed of Triton X-100-(NH4)2SO4-H2O was proposed for extraction and separation of tungsten(VI) from aqueous solution without using any extractant. The effects of aqueous pH, concentration of ammonium sulfate, Triton X-100 and tungsten, extracting temperature on the extraction of tungsten were investigated. The extraction of tungsten has remarkable relationship with aqueous pH and are to above 90% at pH=1.0-3.0 under studied pH range (pH=1.0-7.0) and increases gradually with increasing Triton X-100 concentration, but decreases slightly with increasing ammonium sulfate concentration. The extraction percentage of tungsten is hardly relevant to temperature but its distribution coefficient linearly increases with increasing temperature within 303.15-343.15K. The distribution coefficient of tungsten increases with the increase of initial tungsten concentration (0.1-3%) and temperature (303.15 K-333.15K). The solubilization capacity of tungsten in Triton X-100 micellar phase is independent of temperature. FT-IR analysis reveals that there is no evident interaction between polytungstate anion and ether oxygen unit in Triton X-100, and DLS analysis indicates that zeta potential of Triton X-100 micellar phase have a little change from positive to negative after extracting tungsten. Based on the above-mentioned results, it can be deduced that polytungstate anions are solubilized in hydrophilic outer shell of Triton X-100 micelles by electrostatic attraction depending on its relatively high hydrophobic nature. The stripping of tungsten is mainly influenced by temperature and can be easily achieved to 95% in single stage stripping. The tungsten (VI) is separated out from solution containing Fe(III), Co(II), Ni(II), Cu(II), Zn(II), Al(III), Cr(III) and Mn(II) under the suitable conditions.

  6. Indirect Determination of Ascorbic Acid with Ammonium Sulfate and Isopropyl Alcohol by Extraction-flotation of Copper

    Institute of Scientific and Technical Information of China (English)

    Shao Mei WANG; Yun XING; Quan Min LI


    A new method of indirect determination of ascorbic acid(Vc) with ammonium sulfateand isopropyl alcohol by extraction-flotation of copper is studied in this paper. It shows that asmall amount of Cu(Ⅱ) can be reduced to Cu(Ⅰ) by Vc, then Cu(Ⅰ) reacted with the SCN-,which precipitated on the interface of isopropyl alcohol and H2O. A good linear relationship isobserved between the flotation yield(E) of Cu(Ⅱ) and the amount of Vc. The detection limit forVc is 1.76μ g/mL. The method is simple, rapid (5 min), but suffers from little interference ofcommon anions and cations. It has been successfully applied for the determination of Vc infruits.

  7. Temperature- and pH-dependent aqueous-phase kinetics of the reactions of glyoxal and methylglyoxal with atmospheric amines and ammonium sulfate (United States)

    Sedehi, Nahzaneen; Takano, Hiromi; Blasic, Vanessa A.; Sullivan, Kristin A.; De Haan, David O.


    Reactions of glyoxal (Glx) and methylglyoxal (MG) with primary amines and ammonium salts may produce brown carbon and N-containing oligomers in aqueous aerosol. 1H NMR monitoring of reactant losses and product appearance in bulk aqueous reactions were used to derive rate constants and quantify competing reaction pathways as a function of pH and temperature. Glx + ammonium sulfate (AS) and amine reactions generate products containing C-N bonds, with rates depending directly on pH: rate = (70 ± 60) M-1 s-1fAld [Glx]totfAm [Am]tot, where fAld is the fraction of aldehyde with a dehydrated aldehyde functional group, and fAm is the fraction of amine or ammonia that is deprotonated at a given pH. MG + amine reactions generate mostly aldol condensation products and exhibit less pH dependence: rate = 10[(0.36 ± 0.06) × pH - (3.6 ± 0.3)] M-1 s-1fAld [MG]tot [Am]tot. Aldehyde + AS reactions are less temperature-dependent (Ea = 18 ± 8 kJ mol-1) than corresponding amine reactions (Ea = 50 ± 11 kJ mol-1). Using aerosol concentrations of [OH] = 10-12 M, [amine]tot = [AS] = 0.1 M, fGlx = 0.046 and fMG = 0.09, we estimate that OH radical reactions are normally the major aerosol-phase sink for both dicarbonyl compounds. However, reactions with AS and amines together can account for up to 12 and 45% of daytime aerosol-phase glyoxal and methylglyoxal reactivity, respectively, in marine aerosol at pH 5.5. Reactions with AS and amines become less important in acidic or non-marine aerosol, but may still be significant atmospheric sources of brown carbon, imidazoles, and nitrogen-containing oligomers.

  8. Effects of long-term exposure to ammonium sulfate particles on growth and gas exchange rates of Fagus crenata, Castanopsis sieboldii, Larix kaempferi and Cryptomeria japonica seedlings (United States)

    Yamaguchi, Masahiro; Otani, Yoko; Li, Peiran; Nagao, Hiroshi; Lenggoro, I. Wuled; Ishida, Atsushi; Yazaki, Kenichi; Noguchi, Kyotaro; Nakaba, Satoshi; Yamane, Kenichi; Kuroda, Katsushi; Sano, Yuzou; Funada, Ryo; Izuta, Takeshi


    To clarify the effects of long-term exposure to ammonium sulfate (AS) particles on growth and physiological functions of forest tree species, seedlings of Fagus crenata, Castanopsis sieboldii, Larix kaempferi and Cryptomeria japonica were exposed to submicron-size AS particles during two growing seasons from 3 June 2011 to 8 October 2012. The mean sulfate concentration in PM2.5 increased during the exposure inside the chamber in 2011 and 2012 by 2.73 and 4.32 μg SO42- m-3, respectively. No significant effects of exposure to AS particles were detected on the whole-plant dry mass of the seedlings. These results indicate that the exposure to submicrometer AS particles at the ambient level for two growing seasons did not significantly affect the growth of the seedlings. No significant effects of exposure to AS particles were found on the net photosynthetic rate in the leaves or needles of F. crenata, C. sieboldii and L. kaempferi seedlings. Also, in the previous-year needles of C. japonica seedlings, exposure to AS particles significantly reduced the net photosynthetic rate, which may be caused by the reduction in the concentration of ribulose-1, 5-bisphosphate carboxylase/oxygenase (Rubisco). On the contrary, in current-year needles of C. japonica seedlings, net photosynthetic rate significantly increased with exposure to AS particles, which may be the result of increases in stomatal conductance and concentrations of Rubisco and chlorophyll. Furthermore, exposure to AS particles correlated with an increase in concentrations of NH4+, free amino acid and total soluble protein, suggesting that AS particles may be deliquesced, absorbed into the leaves and metabolized into amino acid and protein. These results suggest that net photosynthesis in the needles of C. japonica is relatively sensitive to submicron-size AS particles as compared with the other three tree species.

  9. Influence of the Salting-out Effect of Ammonium Sulfate on the Gas-Particle Partitioning of Organic Compounds in the Atmosphere (United States)

    Wang, C.; Lei, Y. D.; Endo, S.; Wania, F.


    As one of the major salts in the atmosphere, ammonium sulfate ((NH4)2SO4) influences significantly the partitioning of organic compounds into atmospheric aqueous phases. This salting out effect has important implications regarding the reactivity, transport and fate of organic compounds in atmospheric waters, particularly in aerosol particles because of the relatively large amount of salts present. However, very few studies have quantified the salting out effect of (NH4)2SO4. For the first time, we measured salting-out coefficients (or Setschenow constants) (KS [M-1]) for a large and diverse group of organic compounds in (NH4)2SO4 solutions at a wide range of salt concentrations, providing a reliable database for model development. KS values for (NH4)2SO4 are correlated with and always higher than KS for sodium chloride (NaCl), suggesting a higher salting-out effect of (NH4)2SO4. Three modeling approaches: a poly-parameter linear free energy relationship (pp-LFER), the quantum-chemical COSMOtherm software and the group contribution method AIMOFAC, were calibrated and evaluated in terms of their capability to predict KS. Relative merits of the prediction methods were identified. These models can be applied to estimate Setschenow constants for atmospherically relevant compounds involved in secondary organic aerosol formation based on chemical structure alone.

  10. Synergistic effect of sodium dodecyl sulfate and cetyltrimethyl ammonium bromide on the corrosion inhibition behavior of l-methionine on mild steel in acidic medium

    Directory of Open Access Journals (Sweden)

    M. Mobin


    Full Text Available The corrosion inhibition behavior of amino acid l-methionine (LMT separately and in combination with very low concentration of surfactants sodium dodecyl sulfate (SDS and cetyltrimethyl ammonium bromide (CTAB on mild steel in 0.1 M H2SO4 solution was studied, using weight loss and potentiodynamic polarization measurement techniques. The studies were carried out in the temperature range of 30–60 °C. The surface morphology of the corroded steel samples was studied by scanning electron microscopy (SEM and atomic force microscopy (AFM.The results show that LMT is an effective inhibitor for mild steel corrosion in 0.1 M H2SO4 which is synergistically improved in the presence of SDS and CTAB. The mixed LMT and CTAB is more effective as an inhibitor than mixture of LMT and SDS. The SEM and AFM photographs show a clearly different surface morphology in the presence of additives. LMT alone and in combination with surfactants obeys Langmuir adsorption isotherm from the fit of the experimental data of all concentrations and temperatures studied. Phenomenon of physical adsorption is proposed from the trend of the IE with temperature and also the values of activation energy (Ea, standard enthalpy of adsorption (ΔHads, and standard free energy of adsorption (ΔGads obtained. The results obtained by potentiodynamic polarization measurements are consistent with the results of the weight loss measurements. LMT acts as a mixed type inhibitor.

  11. Cleaning technique of ammonium sulfate evaporator pipes scale%硫铵蒸发器列管结垢的清洗工艺

    Institute of Scientific and Technical Information of China (English)

    张福元; 姚立斌


    This paper presents the pipes scale of ammonium sulfate falling film evaporator,elements composition of the scale was analyzed by X Ray Fluorescence(XRF) and quantitative analysis by chemistry mothed,adopting the dredge water cleaning,heating alkaline cleaning,room acid cleaning and water cleaning passivation multistep cleaning method by the results of analysis on scale,industrial cleaning results,this process method is simple and effect,it can deal with the hard evaporator scale that conventional physical approach is difficult to dredge,has good application value.%介绍了硫铵降膜蒸发器列管的结垢情况,对结垢进行了X衍射荧光光谱定性分析和化学定量分析,根据分析结果对列管进行疏通水洗—加热碱洗—常温酸洗—水洗钝化等多步清洗工艺。试验证明,该工艺简单、效果良好,能够处理常规物理方法难以处理的质硬蒸发器结垢,具有良好的推广应用价值。

  12. Restraining Na-Montmorillonite Delamination in Water by Adsorption of Sodium Dodecyl Sulfate or Octadecyl Trimethyl Ammonium Chloride on the Edges

    Directory of Open Access Journals (Sweden)

    Hongliang Li


    Full Text Available The delamination of montmorillonite in water leads to sliming in ore slurry, which is detrimental to mineral flotation and solid/water separation. In this work, the delamination of Na-montmorillonite (Na-MMT has been restrained by sodium dodecyl sulfate (SDS or octadecyl trimethyl ammonium chloride (1831 through the adsorption on the edge of the mineral. The experimental results have shown that the pretreatment by adding SDS and 1831 could greatly reduce the Stokes size percentage of −1.1 µm particles in the aqueous Na-MMT suspension. From the X-ray diffractometer (XRD results, the interlayer spacing of the MMT pre-treated by SDS and 1831 is smaller than that of original MMT particles. Adsorption position of SDS and 1831 on MMT surfaces was analyzed by the measurements of adsorption capacity of SDS and 1831, inductively-coupled plasma spectra, and zeta potential before and after the plane surface of MMT was covered with tetraethylenepentaminecopper ([Cu(tetren]2+. The results indicated that SDS and 1831 are adsorbed on the edge and the whole surface of Na-MMT, respectively. Delamination of MMT could be well restrained by the adsorption of SDS and 1831 on the edges of MMT.

  13. Technology Optimization Research of Calcining Asbestos Tailings with Ammonium Sulfate%石棉尾矿硫酸铵焙烧工艺优化研究

    Institute of Scientific and Technical Information of China (English)

    刘姝抒; 宋贝; 胡志波; 牛保军; 郑水林


    Asbestos tailings were preprocessed by ball-milling and calcining. This paper studied the influence of calcination temperature, calcination time and milling time on the roasting effect of asbestos tailings and ammonium sulfate. The result showed that the optimum conditions were that calcination temperature was 500℃, calcination time was 1 h, milling time was 18 min. Through being preprocessed, the leaching ratio of MgO was up from 70.03%to 95.29%.%对石棉尾矿进行预先煅烧和研磨处理,研究了煅烧温度、煅烧时间和研磨时间对石棉尾矿硫酸铵焙烧效果的影响,得到最佳的预处理条件:煅烧温度为500℃,煅烧时间为1 h,研磨时间为18 min。经过预处理后,石棉尾矿硫酸铵焙烧氧化镁溶出率从70.03%提高到95.29%。


    Institute of Scientific and Technical Information of China (English)

    吴艳平; 赵春霞; 李全民; 耿新华


    The behavior of Ammonium sulfate-Potassium iodide-Ethanol System For Extraction and Separation of Bismuth and the condition of separating of ethanol from water have been study.It shows that as the extracting regent,ethanol,can extract BiI3-6.If pH=3~6,Bi(Ⅲ) can be separated from Fe(Ⅲ)、Co(Ⅱ)、Mn(Ⅱ)、Cu(Ⅱ)、Ni(Ⅱ)、Mo(Ⅵ).

  15. Research of Magnesium Extracted from Asbestos Tailings by Ammonium Sulfate Calcination Method%硫酸铵焙烧活化石棉尾矿提取镁实验研究

    Institute of Scientific and Technical Information of China (English)

    曾丽; 孙红娟; 彭同江


    本实验采用硫酸铵与石棉尾矿用高温炉焙烧的方法提取镁.首先利用差热-热重法分析石棉尾矿与硫酸铵混合物的热分解和化学反应的热效应,得出石棉尾矿与硫酸铵混合物在240~ 500℃下产生分解、失重.将石棉尾矿与硫酸铵混合均匀后在320℃、400℃和460℃下焙烧1h,用XRD分析焙烧产物,得出在320℃时石棉尾矿和硫酸铵反应主要生成(NH4)2Mg(SO4)2和(NH4)2Mg2(SO4)3;在400℃时主要生成(NH4)2Mg2(SO4)3;在460℃时主要生成MgSO4,由于吸水变为MgSO4·6H2O.研究了硫酸铵与石棉尾矿不同物质的量的配比、焙烧温度和焙烧时间对镁浸取率的影响,得出当硫酸铵与石棉尾矿物质的量之比为2∶1、焙烧温度为460℃、焙烧时间为60 min时,镁的浸取率为83.1%.%In this paper, magnesium was extracted from asbestos tailings by ammonium sulfate calcination method. First the thermal behavior and the chemical calorific effect of the blend of asbestos tailings and ammonium sulfate were characterized by TG-DTA, it showed that asbestos tailings and ammonium sulfate were decompounded at 240~500 ℃. Then the asbestos tailings were uniform mixed with ammonium sulfate and calcined at 320 ℃, 400 ℃, and 460 ℃ for 1 h respectively and the calcinated products were studied by XRD. The results indicated that asbestos tailings and ammonium sulfate react each other to generate (NH4)2Mg(SO4)2 and (NH4)2Mg2(SO4)3 at 320 °C; the main product was (NH4)2Mg2(SO4)3 at 400 ℃ and MgSO4 at 460℃ respectively. Then the influence of the molar ratio of ammonium sulfate and asbestos tailings, the calcination temperature, the calcination time were studied. The results indicated that when the molar ratio of ammonium sulfate and asbestos tailings is 2 : 1, the calcination temperature is 460 ℃, the calcination time is 60 min, the leaching rate of Mg is 83.1%.

  16. Study on crystallization of ammonium sulfate and ammonium nitrate by-produced from desulfurization and denitrification with oxidation and ammonia methods%氧化法、氨法脱硫、脱硝副产物硫酸铵、硝酸铵结晶研究

    Institute of Scientific and Technical Information of China (English)

    范学友; 贾勇; 钟秦


    Ammonium sulfate and ammonium nitrate were by-produced during the simultaneous desulfurization and denitrification for the flue gas by the combined oxidation and ammonia process.Ammonium nitrate was added on the basis of single crystallization of ammonium sulfate.The products were analyzed by laser particle size distribution meter,XRD,and SEM.Effects of evaporation temperature ,pH, stirring speed, and fly ash content on mixed crystallization of ammonium sulfate and ammonium nitrate were investigated.Results showed that the product of mixed crystals was cubic crystal; under the conditions of pH = 5, temperature of 60 ℃, stirring speed of 200 r/min,and no fly ash existed the distribution of particle size was even; the crystal size was the biggest when the fly ash content was 4 g/L.%运用氧化和氨法脱硫相结合的烟气同时脱硫、脱硝技术得到的副产物中主要含有硫酸铵和硝酸铵.在原有硫酸铵单独结晶的基础上加入了硝酸铵,利用激光粒度分布仪、XRD、扫描电镜对产物进行了分析,考察了蒸发温度、pH、搅拌速度、飞灰含量对二者混合结晶的影响.结果发现:混合结晶的产物为立方晶型;当结晶的pH控制在5左右、温度为60℃、搅拌速度为200r/min、无飞灰存在时得到的晶体粒径分布均匀;飞灰含量为4g/L时得到的晶体的平均粒径最大.

  17. 硫酸铵在蛋白质含量测定中的参比作用初探%The significance of ammonium sulfate in the determination of concentration of protein

    Institute of Scientific and Technical Information of China (English)

    王亚棋; 黎隽; 刘立科; 刘东鸣; 张篧; 马力; 李剑利


    Objective To determinate the concentration of protein,the second method of nitrogen measurement in appendix Ⅶ D of Chinese pharmacopoeia 2010 edition is always used. The complicated experiments used to leads puzzling result,for there is not right reference protein.We tried to find a way to determinate the concentration of protein in regeneration scaf old of ar-ticular cartilage by using ammonium sulfate.Methods triplet ammonium sulfate taken was used as reference to determinate the concentration of protein in the samples.Results we got a nearly 100% recovery rate of ammonium sulfate irrespective of the dif erence digestion with protein samples.Conclusions In the case of get ing no protein reference,Ammonium sulfate could be used as reference in the kjeldahl determination to improve the credibility.%目的:中国药典2010版附录Ⅶ D 氮测定法第二法,是蛋白质含量测定的经典方法。但参考蛋白难于获得,检测结果缺乏参比性。本文尝试以分析纯硫酸铵为参考品,检测关节软骨再生支架样品中的蛋白质含量。方法分别称取三份硫酸铵,与蛋白样品一起,在相同条件下测试其回收率,用以参照评价蛋白样品的检测结果。结果硫酸铵的回收率接近100%,不考虑消化样品的差异,可以确认样品测定结果。结论在没有标准蛋白作参比的情况下,在凯氏定氮法中引入硫酸铵,可以很好的监测实验结果。

  18. The ferrous ammonium sulfate solid system, as dosemeter for processes at low temperatures and high doses of gamma radiation; El sistema sulfato ferroso amoniacal solido, como dosimetro para procesos a bajas temperaturas y altas dosis de radiacion gamma

    Energy Technology Data Exchange (ETDEWEB)

    Juarez C, J.M.; Ramos B, S.; Negron M, A. [ICN-UNAM, 04510 Mexico D.F. (Mexico)


    This paper presents the results obtained from a study of the radiation induced oxidation of crystalline ferrous ammonium sulfate with gamma rays at 295 K, 263 K and 77 K and dose from 0 to 300 kGy. The radiation induced decomposition of ferrous ammonium sulfate has been studied by the dissolution of the irradiated salt in 0,8 N sulfuric acid. The main product is Fe{sup 3+} and molar concentration of ferric ion was determined spectrophotometrically in the UV region at 304 nm. The optical density values showed a linear dependence with dose, indicating that the data obtained might be used to create a calibrating curve. Color in irradiated salt changes from blue to green, yellow and orange according to the absorbed dose. The accuracy and the reproducibility of the system were tested. In addition, some other characteristics make possible the use of this system as a dosimeter, similar to Fricke chemical dosemeter, at low temperatures and high dose. (Author)


    Ammonium-nitrogen fertilizers are used in large quantities in agricultural areas of the United States, including the grass-seed fields of the Willamette Valley of western Oregon, and are a potential threat to larval amphibians living in the treat areas (Edwards and Daniel 1994, M...

  20. Synthesis and Anticoagulant Activity of Quaternary Ammonium Cationic Starch Sulfates%阳离子淀粉硫酸酯的制备及其抗凝血活性

    Institute of Scientific and Technical Information of China (English)

    樊李红; 沈元; 徐咏梅; 江澜; 王晓东; 周月; 潘晓然


    Quaternary ammonium cationic starch sulfate(QACSS) was synthesized by chemical modification of quaternary ammonium cationic starch(QACS) with trisulfonated sodium amine(N(SO_3Na)_3).This sulfating agent was close to neutral,and synthesized by reaction of sodium bisulfite and sodium nitrite in aqueous solution.The reaction conditions for the sulfonation process were optimized through posttest-only control group design.The optimal pH value of the sulfating agent solution was 10.0,the optimal ratio of sulfating agent to QACS was 2.0/314.5(mol/g),the reaction temperature was 40 ℃,the reaction time was about 22 h,respectively.The DS of QACSS was measured by barium sulfate nephelometry method,and the biggest DS was 1.83.The molecular weight was determined as 2.51×104 by static light scattering.Anticoagulant activity of QACSS was investigated by APTT,TT and PT assays.The results showed that QACSS exhibited good anticoagulant activity.The results also showed that with the increase of DS and concentration,APTT increased significantly,but TT and PT do not increased obviously.APTT prolonged as the molecular weight rose firstly and then decreased slowly with further increase in molecular weight.The best molecular weight was around 2.51×104.In addition,the anticoagulant activity of QACSS was better than QACS.%采用由亚硫酸氢钠和亚硝酸钠在水溶液中合成的近似中性的酯化剂N(SO3Na)3在水溶液中对季铵型阳离子淀粉(QACS)进行改性处理,制备了季铵型阳离子淀粉硫酸酯(QACSS).通过单因素实验优化得到酯化反应的最佳反应条件:pH=10.0,酯化剂的摩尔量与QACS的质量之比2∶314.5(mol/g),反应温度40℃,反应时间为22 h.通过测定凝血酶原时间(PT)、凝血活酶时间(APTT)以及凝血酶时间(TT),证明了QACSS有较优的抗凝血活性.随着QACSS取代度和浓度的增加,APTT明显增长,而TT与

  1. 苦土—硫酸铵循环法制备氢氧化镁的研究%Study on Preparation of Magnesium Hydroxide from Bitter Earth-Ammonium Sulfate by Circulation Method

    Institute of Scientific and Technical Information of China (English)

    杨定明; 石荣铭; 王清成; 白进伟


    本文对苦土—硫酸铵循环法制备氢氧化镁的工艺条件进行了试验研究,找到了提高产品质量以及镁和氨的回收率的适宜工艺条件,对苦土资源合理利用具有参考价值。%In this paper,the technological conditions for preparation of magnesium hydroxide from bitter earth-ammonium sulfate by circulation method have been studied,and the suitable conditions to increase quality of product and recovery of ammonia and magnesium oxide have been found.It has important significance for rational utilization of bitter earth resources.

  2. Study on Flotation Separation of Cadmium with Ammonium Sulfate-Potassium Iodide-crystal Violet System%用硫酸铵-碘化钾-结晶紫体系浮选分离镉

    Institute of Scientific and Technical Information of China (English)

    温欣荣; 李全民; 卫伟


    The flotation separation behaviour of cadmium with ammonium sulfate-potassium iodide-crystal violet system and the conditions for the separation of cadmium with other metal ions were studied. It was showed that Cd(Ⅱ) could be separated completely from Zn(Ⅱ)、Fe(Ⅲ)、Co(Ⅱ)、Ni(Ⅱ)、Mn(Ⅱ) 、Al(Ⅲ) by flotation on the optimum condition.%研究了硫酸铵-碘化钾-结晶紫体系浮选分离镉的行为及其与常见离子分离的条件,该体系能使 Cd(Ⅱ) 与常见离子 Zn(Ⅱ)、Fe(Ⅲ)、Co(Ⅱ)、Ni(Ⅱ)、Mn(Ⅱ)、Al(Ⅲ)分离。

  3. Dessecação de plantas daninhas com glyphosate em mistura com ureia ou sulfato de amônio Weed desiccation with glyphosate mixed with urea or ammonium sulfate

    Directory of Open Access Journals (Sweden)

    S.J.P. Carvalho


    Full Text Available O glyphosate é um herbicida não-seletivo, sistêmico, usado para controle de plantas daninhas anuais e perenes em todo o mundo. A absorção da molécula do glyphosate ocorre pelos tecidos fotossinteticamente ativos das plantas, porém alguns fatores podem reduzir sua eficácia, como a morfologia e diversidade de espécies, chuva após aplicação, qualidade da água e misturas em tanque com outros defensivos, entre outros. Objetivou-se com este trabalho avaliar a influência da adição de sulfato de amônio ou ureia em calda na eficácia do herbicida glyphosate para dessecação de plantas daninhas. Dois experimentos foram desenvolvidos em Piracicaba - SP, com aplicações de glyphosate (720 e 1.440 g ha-1 isolado ou combinado com duas doses de sulfato de amônio (7,5 e 15,0 g L-1 ou ureia (2,5 e 5,0 g L-1 sobre as plantas daninhas: apaga-fogo (Alternanthera tenella e capim-massambará (Sorghum halepense. Para a espécie menos suscetível ao herbicida (capim-massambará, a adição de fontes nitrogenadas à menor dose de glyphosate acelerou a morte das plantas, elevando os níveis de controle em até 7,3% na avaliação de 21 dias após aplicação (DAA dos tratamentos. Contudo, os efeitos não foram observados nas avaliações de controle, massa fresca e seca, conduzidas aos 28 DAA. A dose recomendada de glyphosate para cada espécie proporcionou controle satisfatório, sem a necessidade de adição de sulfato de amônio ou ureia.Glyphosate is a non-selective systemic herbicide used to control annual and perennial weeds worldwide. Molecule absorption occurs through the plant's photosynthetically-active tissues; however, some factors might reduce its efficacy, such as morphology and specific diversity, rain after application, water quality and tank mixtures with other chemicals. Thus, this work aimed to evaluate the influence of ammonium sulfate or urea addiction to spray tank on glyphosate efficacy for weed desiccation. Two trials were

  4. [Characteristics of the precipitation of the antigenic structures of the tick-borne encephalitis virus using polyethylene glycol and ammonium sulfate]. (United States)

    Liapustin, V N; Gritsun, T S; Lashkevich, V A


    When immunoelectrophoretic methods were used for analysis of tick-borne encephalitis (TBE) virus antigens, TBE virus virion antigen (VA) from the virus-containing tissue culture fluid sedimented upon addition of polyethylene glycol (PEG) up to 7% whereas upon addition of ammonium sulphate (AS) the bulk of VA sedimented in the range of 40-70% salt saturation. The non-virion antigens (NA) sedimented at all PEG (up to 22%) and AS (up to 70% saturation) concentrations. In stringent ultracentrifugation procedure (12-13 X 10(6) g X min), the bulk of VA and a small portion of NA are pelleted. Repeated ultracentrifugation results in sedimentation of additional amounts of VA and NA. The sedimentable NA are pelleted by low PEG (up to 5-7%) and AS (up to 20-30%) concentrations and differ in their interaction with antibodies in the course of immunoelectrophoresis from nonprecipitatable ("soluble") NA. Combined sedimentation of antigens with AS (in the range of 40-70% saturation), intensive dialysis and subsequent sedimentation with low and high PEG concentrations produces homogeneous antigenic preparations containing VA or "soluble" NA.

  5. Utilization of sulfate additives in biomass combustion: fundamental and modeling aspects

    DEFF Research Database (Denmark)

    Wu, Hao; Jespersen, Jacob Boll; Grell, Morten Nedergaard;


    Sulfates, such as ammonium sulfate, aluminum sulfate and ferric sulfate, are effective additives for converting the alkali chlorides released from biomass combustion to the less harmful alkali sulfates. Optimization of the use of these additives requires knowledge on their decomposition rate...... and product distribution under high temperature conditions. In the present work, the decomposition of ammonium sulfate, aluminum sulfate and ferric sulfate was studied respectively in a fast-heating rate thermogravimetric analyzer for deriving a kinetic model to describe the process. The yields of SO2 and SO3...... of different sulfates indicated that ammonium sulfate has clearly strongest sulfation power towards KCl at temperatures below 800oC, whereas the sulfation power of ferric and aluminum sulfates exceeds clearly that of ammonium sulfate between 900 and 1000oC. However, feeding gaseous SO3 was found to be most...

  6. (乙醇+丙酮)-硫酸铵二元双水相分离萃取盐酸四环素%Ethanol and acetone-ammonium sulfate binary aqueous two-phase extraction separation of tetracycline

    Institute of Scientific and Technical Information of China (English)

    关卫省; 邓江华; 韩娟


    基于小分子醇双水相体系和小分子有机物双水相体系,建立了(乙醇+丙酮)-(NH4)2SO4形成的二元双水相体系萃取盐酸四环素的新方法.研究了分相盐、醇及小分子有机物的类型、用量及比例、温度、溶液酸度、共存物质对盐酸四环素分配行为的影响.结果表明,硫酸铵浓度为41%、无水乙醇与丙酮体积比为2:1、溶液酸度在pH 4.5-5范围、温度为25℃二元双水相体系对四环素有较高萃取率可达90%,分配系数达到57.当测试允许相对误差为±7%时,浓度为75 mg·L-1的盐酸四环素,K+、Na+、F-、Cl-、NO3-、Br-浓度均为10%对测定结果无干扰,1.5倍的盐酸美他环素、35倍的氯霉素、青霉素和红霉素、80倍的淀粉和蔗糖、400倍的葡萄糖和果糖对测定结果不发生干扰.%Based on small molecule alcohol and organic molecule aqueous two -phase system, a new method was developed for extraction of tetracycline hydrochloride in ethanol-acetone-ammonium sulfate binary aqueous system. Several factors on the tetracycline hydrochloride allocation behavior was studied, including the type, amounts and relative proportions of salt-alcohol-small molecular organics, temperature, pH and the coexisting substances. The results showed that when ammonium sulfate was 41% , the volume ratio of absolute ethyl alcohol and acetone was 2:1, and the solution pH was 4. 5-5, the extraction rate and the distribution coefficient of tetracycline hydrochloride were 90% and 57 respectively. The relative error was ±7% , the ions including K+ , Na+ , F- , Cl- , NO3- , Br- , the hydrochloride metacycline, and other components in the system such as chloramphenicol penicillin, erythromycin, starch and sucrose, glucose and fructose have not any effect on the extraction behavior.

  7. Solubilities of carbon dioxide and oxygen in the ionic liquids methyl trioctyl ammonium bis(trifluoromethylsulfonyl)imide, 1-butyl-3-methyl imidazolium bis(trifluoromethylsulfonyl)imide, and 1-butyl-3-methyl imidazolium methyl sulfate. (United States)

    Bahadur, Indra; Osman, Khalid; Coquelet, Christophe; Naidoo, Paramespri; Ramjugernath, Deresh


    Ionic liquids (ILs) are being considered as solvents for gas absorption processes as they have the potential, in general, for improved efficiency of gas separations, as well as lower capital and operating costs compared to current commercial processes. In this study the solvent properties of ILs are investigated for use in the absorption of carbon dioxide (CO2) and oxygen (O2). The absorption of these gases in ILs was measured in the temperature range 303.15-333.15 K and at pressures up to 1.5 MPa by gravimetric analysis. The ILs used were methyl trioctyl ammonium bis (trifluoromethylsulfonyl) imide ([MOA][Tf2N]), 1-butyl-3-methyl imidazolium bis (trifluoromethylsulfonyl) imide ([BMIM][Tf2N]), and 1-butyl-3-methyl imidazolium methyl sulfate ([BMIM][MeSO4]). The measurement technique employed in this study is fast and accurate, and requires small quantities of solvent. The results indicated that absorption of both gases increased with a decrease in operating temperature and an increase in pressure. [MOA][Tf2N] had the highest CO2 and O2 solubility. [BMIM][Tf2N] was determined to have the highest selectivity for CO2 absorption. [BMIM][MeSO4] achieved the lowest CO2 absorption with a moderate O2 absorption, revealing this IL to be the least desirable for CO2 and O2 absorption. Calculation of Henry's law constants for all systems confirmed the deductions made from absorption data analysis. Calculation of enthalpy and entropy of absorption for each system revealed CO2 absorption in [MOA][Tf2N] to be the least sensitive to temperature increases. The absorption data was modeled using the generic Redlich-Kwong cubic equation of state (RK-EOS) coupled with a group contribution method.

  8. Calcining Serpentine with Ammonium Sulfate for Preparation of Ultrafine Magnesium Hydroxide%用蛇纹石硫酸铵焙烧法制备超细氢氧化镁的研究

    Institute of Scientific and Technical Information of China (English)

    宋贝; 刘超; 郑水林; 戴瑞; 侯会丽


    Calcining serpentine with ammonium sulfate to extract magnesium for preparaion of ultrafine magnesium hydroxide. This paper studies the effect of temperature on the performance of the preparation of ultrafine magnesium hydroxide, which come to the conclusion the appropriate reaction temperature is 40℃. The results show that superfine magnesium hydroxide particles occur agglomeration and have large specific surface area. In order to overcome the agglomeration of the magnesium hydroxide and decrease the surface area, the magnesium hydroxide hydrothermal reaction is carried on and the appropriate condition of hydrothermal time is 3 h. Through analysis of their chemical composition, particle size distribution, surface area and SEM, it shows that after the hydrothermal reaction magnesium hydroxide specific surface area is 13.79 m2/g, the content of MgO is 68.23%, and has good crystalline form.%  以蛇纹石为原料,通过硫酸铵焙烧法提取蛇纹石中的镁,并制备超细氢氧化镁。研究了温度对制备超细氢氧化镁性能的影响,得出适宜反应温度为40℃,SEM测试结果表明,制备的超细氢氧化镁颗粒间发生了较多团聚,比表面积较大。为克服氢氧化镁的团聚现象,降低比表面积,将氢氧化镁在反应釜中进行水热反应,得出适宜水热时间为3 h。化学分析以及粒度、比表面积、SEM测试结果表明,水热反应后氢氧化镁比表面积为13.79 m2/g,MgO含量为68.23%,晶型较好。

  9. Effects of brief and intermediate exposures to sulfate submicron aerosols and sulfate injections on cardiopulmonary function of dogs and tracheal mucous velocity of sheep

    Energy Technology Data Exchange (ETDEWEB)

    Sackner, M.A. (Mount Sinai Medical Center, Miami Beach, FL); Dougherty, R.L.; Chapman, G.A.; Cipley, J.; Perez, D.; Kwoka, M.; Reinhart, M.; Brito, M.; Schreck, R.


    Pulmonary mechanics of anesthetized dogs were not changed or were minimally altered by breathing the following compounds as submicron aerosols in concentrations up to 17.3 mg/m/sup 3/ for 7.5 min: (1) sodium chloride (as a control), (2) sodium sulfate, (3) ammonium sulfate, (4) zinc sulfate, (5) zinc ammonium sulfate, (6) ammonium bisulfate, (7) aluminum sulfate, (8) manganese sulfate, (9) nickel sulfate, (10) copper sulfate, (11) ferrous fulfate, and (12) ferric sulfate. Submicron aerosols of these compounds in concentrations of 4.1 to 8.8 mg/m/sup 3/, administered for 4 h to anesthetized dogs, did not affect mechanics of breathing, hemodynamics, and arterial blood gases. In conscious sheep, tracheal mucous velocity was not altered by exposure to the submicron aerosols of the sulfate compounds. None of these compounds, injected iv in a dose of 1 mg, had adverse effects on mechanics of breathing, pulmonary and systemic hemodynamics, or arterial blood gases. In 100-mg injections, zinc sulfate and zinc ammonium sulfate produced a fall in cardiac output, systemic hypotension, hypoxemia, and metabolic acidosis. Copper sulfate at this dose produced pulmonary hypertension, a fall in cardiac output, hypoxemia, respiratory acidosis, and a decrease of specific total respiratory conductance. It is concluded that submicron aerosols of sulfate salts do not have adverse cardiopulmonary effects when administered in high concentrations for up to 4 h. However, prolonged exposure to high concentrations of zinc sulfate, zinc ammonium sulfate, and copper sulfate aerosols might have adverse cardiopulmonary effects.

  10. Adição simultânea de sulfato de amônio e ureia à calda de pulverização do herbicida glyphosate Simultaneous addition of ammonium sulfate and urea to glyphosate spray solution

    Directory of Open Access Journals (Sweden)

    S.J.P. Carvalho


    Full Text Available Dois experimentos foram desenvolvidos em casa de vegetação, com o objetivo de avaliar a eficácia do herbicida glyphosate sobre plantas de Digitaria insularis quando soluções de ureia (U; 5 g L-1, sulfato de amônio (SA; 15 g L-1 ou U+SA (2,5 + 7,5 g L-1 foram utilizadas como veículo de pulverização. Aos 28 dias após aplicação, de acordo com as curvas de dose-resposta (primeiro experimento, foram necessários 409 g ha-1 de glyphosate para atingir 50% de controle da planta daninha (C50 quando água sem adjuvantes foi usada como veículo de pulverização. Para obtenção dos mesmos 50% de controle, as doses de glyphosate foram reduzidas para 373, 208 e 189 g ha-1; quando o herbicida foi pulverizado utilizando solução de U, SA ou U+SA, respectivamente. A redução na dose oriunda da combinação de glyphosate e U+SA também foi observada para controles de 80% (C80. No segundo experimento, a adição de U+SA à calda elevou o controle obtido com a menor dose de glyphosate (360 g ha-1, igualando-o à aplicação da maior dose (720 g ha-1 sem adjuvantes. Esses resultados evidenciam efeito complementar de U e SA em elevar a eficácia do glyphosate para controle de D. insularis.Two trials were carried out under greenhouse conditions to evaluate the efficacy of glyphosate on Digitaria insularis plants when urea (U; 5 g L-1; ammonium sulfate (AMS; 15 g L-1 or U+AMS (2.5 + 7.5 g L-1 were used as spray solutions. At 28 days after application, according to dose-response curves (first trial, 409 g ha-1 of glyphosate application were necessary to obtain 50% of weed control (C50 when water without adjuvants was used as spray solution. To reach the same 50% of weed control, glyphosate rates were reduced to 373, 208 and 189 g ha-1, when the herbicide was sprayed using a solution of U, AMS or U+AMS, respectively. Reduction in the dose of glyphosate combined with U+AMS was also observed for controls of 80% (C80. In the second trial, the addition of U

  11. Distribution of nitrogen ammonium sulfate ({sup 15}N) soil-plant system in a no-tillage crop succession; Distribuicao do nitrogenio do sulfato de amonio ({sup 15}N) no sistema solo-planta, em uma sucessao de culturas, sob sistema plantio direto

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, Flavia Carvalho da Silva, E-mail: [Universidade Estadual de Maringa - Campus de Umuarama, PR (Brazil); Libardi, Paulo Leonel, E-mail: [Departamento de Engenharia de Biossistemas, Escola Superior de Agricultura Luiz de Queiroz, Piracicaba, SP (Brazil)


    the n use by maize (Zea mays, l.) is affected by n-fertilizer levels. this study was conducted using a sandy-clay texture soil (Hapludox) to evaluate the efficiency of n use by maize in a crop succession, based on {sup 15}N labeled ammonium sulfate (5.5 atom %) at different rates, and to assess the residual fertilizer effect in two no-tillage succession crops (signal grass and corn). Two maize crops were evaluated, the first in the growing season 2006, the second in 2007, and brachiaria in the second growing season. The treatments consisted of n rates of 60, 120 and 180 kg ha{sup -1}in the form of labeled {sup 15}N ammonium sulfate. This fertilizer was applied in previously defined subplots, only to the first maize crop (growing season 2006). The variables total accumulated n; fertilizer-derived n in corn plants and pasture; fertilizer-derived n in the soil; and recovery of fertilizer-n by plants and soil were evaluated.The highest uptake of fertilizer n by corn was observed after application of 120 kg ha{sup -1}N and the residual effect of n fertilizer on subsequent corn and brachiaria was highest after application of 180 kg ha{sup -1}N. After the crop succession, soil n recovery was 32, 23 and 27 % for the respective applications of 60, 120 and 180 kg ha{sup -1}N. (author)

  12. 超声辅助异丙醇/(NH4)2SO4双水相体系提取金银花中总黄酮%Extraction of Total Flavonoids fromHoneysuckle with Isopropano/Ammonium Sulfate Aqueous Two-phase System by Ultrasonic-assisted

    Institute of Scientific and Technical Information of China (English)

    程志发; 马燮; 毛华剑


    Aqueous two-phase system was constructed with alcohols / ammonium sulfate / water.The extraction operating conditions of total flavonoids fromhoneysuckle by ultrasonic-assisted were investigated. The experiments results showed that the total flavnoids mostly accumulated in the top phase.It was found that the concentration of isopropanol and ammonium sulfatehad greater effect on aqueous two-phase extraction. The appropriate conditions were as followed: the quality percentage of isopropanol was 30% and the quality percentage of ammonium sulfate was 25%, ultrasonic treat time was 20 min. Under these conditions, the distribution coefficient K was 29.4 and the extraction ratio was 94.8%.%采用异丙醇/硫酸铵/水构建双水相体系,研究在超声波作用下操作条件对金银花中总黄酮萃取效果的影响。实验结果表明,金银花总黄酮主要分布在上相,双水相体系的组成(异丙醇与硫酸铵的浓度)对萃取效果的影响较大。当异丙醇质量分数为30%、硫酸铵质量分数为25%时,常温下超声处理20min,分配系数为29.4,总黄酮的萃取率为94.8%。

  13. Heterogenous uptake of gaseous N(sub 2)O(sub 5) by sulfate aerosols (United States)

    Leu, M. -T.; Kane, S. M.; Caloz, F.


    The heterogeneous uptake of gaseous N sub 2 O sub 5 by ammonium sulfate, ammonium bisulfate, and sulfuric acid aerosols as a function of relative humididty has been investigated at room temperature and atmsopheric pressure.

  14. Viabilidade econômica e risco do cultivo de mamão em função da lâmina de irrigação e doses de sulfato de amônio = Economic viability and cultivation risk of papaya in function of irrigation depth and ammonium sulfate

    Directory of Open Access Journals (Sweden)

    Gustavo Bastos Lyra


    Full Text Available Objetivou-se determinar a viabilidade econômica e o risco do cultivo do mamão na Região Norte do Espírito Santo e comparar os índices econômicos com dados experimentais de irrigação e doses de sulfato de amônio. O experimento foi conduzido na Fazenda Caliman Agrícola S.A., em Linhares, Estado do Espírito Santo. Foram avaliadas, separadamente, duas variedades de mamão, Golden e UENF Caliman 01, em cinco níveis de irrigação (50, 70, 90, 110 e 130% da evapotranspiração de referência, combinados com quatro doses de sulfato de amônio (90, 188, 288 e 377 kg ha-1 mês-1. Na determinação dos riscos e índices da cultura do mamão utilizou-se o cálculo do Valor Presente Líquido, a Taxa Interna de Retorno, a análise de sensibilidade e o método de Monte Carlo. Os tratamentos de irrigação apresentaram diferenças estatísticas significativas (p The aim of this paper was to determine the economic viability and cultivation risk in northern Espírito Santo State and compare theeconomic indices with experimental irrigation data and ammonium sulfate doses. The experiment was carried out at Calima Agricola S.A. farm, in Linhares, ES. Two varieties were evaluated separately, Golden and UENF Caliman 01, in five irrigation levels, combined withfour ammonium sulfate doses. The determination of indices and risks of papaya cultivation utilized the calculation of net present value, internal rate of return, sensitivity analysis and Monte Carlo method. The irrigation treatments showed significant statistical differences (p < 0.05 in relation to productivity. The ammonium sulfate and its interactions with applied irrigation depths did not present significant differences (p < 0.05 for the same variable. By means of a Monte Carlo simulation (triangular simulation, the probability of obtaining negative net present value is 63.2 and 81.4% for Golden and UENF Caliman 01, respectively.

  15. Calibration and measurement uncertainties of a continuous-flow cloud condensation nuclei counter (DMT-CCNC: CCN activation of ammonium sulfate and sodium chloride aerosol particles in theory and experiment

    Directory of Open Access Journals (Sweden)

    D. Rose


    Full Text Available Experimental and theoretical uncertainties in the measurement of cloud condensation nuclei (CCN with a continuous-flow thermal-gradient CCN counter from Droplet Measurement Technologies (DMT-CCNC have been assessed by model calculations and calibration experiments with ammonium sulfate and sodium chloride aerosol particles in the diameter range of 20–220 nm. Experiments have been performed in the laboratory and during field measurement campaigns, extending over a period of more than one year and covering a wide range of operating conditions (650–1020 hPa ambient pressure, 0.5–1.0 L min−1 aerosol flow rate, 20–30°C inlet temperature, 4–34 K m−1 temperature gradient. For each set of conditions, the effective water vapor supersaturation (Seff in the CCNC was determined from the measured CCN activation spectra and Köhler model calculations.

    High measurement precision was achieved under stable laboratory conditions, where relative variations of Seff in the CCNC were generally less than ±2%. During field measurements, however, the relative variability increased up to ±5–7%, which can be mostly attributed to variations of the CCNC column top temperature with ambient temperature.

    To assess the accuracy of the Köhler models used to calculate Seff, we have performed a comprehensive comparison and uncertainty analysis of the various Köhler models and thermodynamic parameterizations commonly used in CCN studies. For the relevant supersaturation range (0.05–2%, the relative deviations between different modeling approaches were as high as 25% for (NH42SO4 and 16% for NaCl. The deviations were mostly caused by the different parameterizations for the activity of water in aqueous solutions of (NH42SO4 and NaCl (activity parameterization, osmotic coefficient, and van't Hoff

  16. Insensitive Ammonium Nitrate. (United States)

    is reduced by replacing the ammonium nitrate with a solid solution of potassium nitrate in form III ammonium nitrate wherein the potassium nitrate...constitutes from more than zero to less than 50 weight percent of the solid solution . (Author)

  17. Effectof Material Ratio on Phase Transfer Rate of Calcium Ions During Reaction between Calcium Sulfate Dihydrate and Ammonium Carbonate%二水硫酸钙与碳酸铵反应过程中物料比对钙离子相转移速率的影响

    Institute of Scientific and Technical Information of China (English)

    陈昌国; 周加贝; 夏素兰; 王子宁; 宫源; 刘仕忠


    选择二水硫酸钙晶须为研究对象,在温度、搅拌速度、料浆浓度不变的条件下,探究了二水硫酸钙与碳酸铵反应过程中物料比 n(NH 4)2 CO 3:nCaSO 4∙2 H 2 O 对钙离子相转移速率的影响。结果表明,物料比在1.05∶1~1.4∶1之间时,生成的碳酸钙沉淀于溶液中,钙离子相转移是溶解-结晶过程,二水硫酸钙转化率和碳酸钙颗粒粒径均随物料比增大而增大,即相转移速率与物料比成正比。%Calcium sulfate dihydrate whiskers were applied under constant temperature,stirring speed and slurry concentration.The material ratio of n(NH 4 )2 CO 3 ∶nCaSO 4 ∙2 H 2 O was changed to study its effect on phase transfer of calcium ions during the reaction between calcium sulfate dihydrate and ammonium car-bonate.The result showed that calcium carbonate crystals were precipitate in solution as the material ratio between 1.05∶1 and 1.4∶1,so corresponding mechanism of calcium ions phase transfer was dissolution-precipitation.It could found that both the conversion rate of calcium sulfate dihydrate and the calcium car-bonate particles size were increased with the increasing value of materials ratio.It indicated that the phase transfer rate of calcium ions was proportional to the material ratio.

  18. Elevated ammonium levels

    DEFF Research Database (Denmark)

    Søgaard, Rikke; Novak, Ivana; MacAulay, Nanna


    ]glutamate uptake and glutamate transport currents but had no effect on EAAT2. The maximal EAAT3-mediated glutamate transport current was increased but the apparent affinities for glutamate and Na(+) were unaltered. Ammonium did not affect EAAT3-mediated transient currents, indicating that EAAT3 surface expression...... was not enhanced. The ammonium-induced stimulation of EAAT3 increased with increasing extracellular pH, suggesting that the gaseous form NH(3) mediates the effect. An ammonium-induced intracellular alkalinization was excluded as the cause of the enhanced EAAT3 activity because 1) ammonium acidified the oocyte...... cytoplasm, 2) intracellular pH buffering with MOPS did not reduce the stimulation, and 3) ammonium enhanced pH-independent cysteine transport. Our data suggest that the ammonium-elicited uptake stimulation is not caused by intracellular alkalinization or changes in the concentrations of cotransported ions...

  19. Glifosato aplicado com diferentes concentrações de uréia ou sulfato de amônio para dessecação de plantas daninhas Glyphosate applied with different concentrations of urea or ammonium sulfate for weed desiccation

    Directory of Open Access Journals (Sweden)

    Saul Jorge Pinto de Carvalho


    Full Text Available Este trabalho foi desenvolvido com o objetivo de avaliar a eficácia do herbicida glifosato, para a dessecação de trapoeraba (Commelina benghalensis e outras plantas daninhas, quando combinado a diferentes concentrações de sulfato de amônio ou uréia. Foram conduzidos três experimentos com tratamentos semelhantes: dois em campo e um em casa de vegetação. Os tratamentos aplicados em campo foram: glifosato (360 g ha-1 de e.a., isolado ou acrescido de quatro concentrações de sulfato de amônio (2,5, 5, 10 e 20 g L-1 ou uréia (1,5, 3, 6 e 12 g L-1; glifosato a 720 g ha-1 de e.a., aplicado isoladamente; e testemunha sem aplicação. Em casa de vegetação, para o controle específico da trapoeraba, as doses de glifosato foram elevadas para 720 (isolado e nas combinações e 1.440 g ha-1 de e.a. A adição de sulfato de amônio à calda do glifosato elevou o controle das plantas daninhas em campo, para as concentrações com até 10 g L-1. O herbicida glifosato não foi eficaz no controle da trapoeraba, em nenhumas das doses usadas. A adição de uréia não promoveu incrementos de controle em condição de campo; porém, para concentrações de até 6 g L-1, melhorou o controle da trapoeraba, na avaliação conduzida aos 28 dias após aplicação.This work was developed with the objective of evaluating glyphosate efficacy for Bengal dayflower (Commelina benghalensis and other weeds desiccation, when combined to different concentrations of ammonium sulfate or urea. Three experiments were carried out with similar treatments: two in field conditions and one in greenhouse. Treatments applied in field conditions were: glyphosate at 360 g ha-1 a.e., isolated or combined to four concentrations of ammonium sulfate (2.5, 5, 10, and 20 g L-1 or urea (1.5, 3, 6, and 12 g L-1; glyphosate at 720 g ha-1 a.e., applied isolately; and checks without application. In greenhouse, for the specific control on Bengal dayflower, glyphosate rates were increased to

  20. 乙醇-硫酸铵双水相萃取镉-碘化钾-罗丹明B离子缔合物%Extraction of cadmium-potassium iodide-rhodamine B ion association complex by alcohol-ammonium sulfate aqueous two-phase

    Institute of Scientific and Technical Information of China (English)

    曾云; 覃事栋; 姚康康; 王影; 肖苗


    In the presence of ammonium sulphate, the extraction behavior of Cd (Ⅱ) based on potassium iodide-Rhodamine B-alcohol system was studied and the optimal condition of phase separation was selected. Results showed that in the pH1 ~3 media, the extraction rate of [CdI4]2- by alcohol-ammonium sulfate aqueous two-phase system is only 35.5% , and the ion association complex, which is formed by adding rhodamine B, can be extracted completely by the aqueous two-phase system. In the system, Cd2+ can be dissociated completely from Zn2+, Fe3+, Co2+, Cu2+, and Ni2+.%研究了在( NH4) 2SO4存在下,碘化钾-罗丹明B-乙醇体系萃取Cd(Ⅱ)的行为及最佳分相条件.实验表明,在pH 1~3时,乙醇-( NH4 )2SO4双水相体系对[ CdI4]2-络阴离子的萃取率只有35.5%;加入罗丹明B后,该体系能完全萃取镉-碘化钾-罗丹明B形成的离子缔合物,而干扰离子Zn2+、Fe3+、Co2+、Cu2+、Ni2+不被萃取,实现Cd2+与上述离子的分离.

  1. Study on extraction separation of antimony(Ⅲ) by n-propyl alcohol-potassium iodide-ammonium sulfate system in the presence of ascorbic acid%在抗坏血酸存在下正丙醇-碘化钾-硫酸铵体系萃 分离锑(Ⅲ)的研究

    Institute of Scientific and Technical Information of China (English)

    郭鹏; 司学芝; 牛媛媛; 钟黎


    The behavior and conditions of extraction separation and concentration of Sb(Ⅲ) from other metal ions by n-propyl alcohol-potassium iodide-ammonium sulfate system in the presence of ascorbic acid were investigated. The results showed that n-propyl alcohol aqueous solution could be well divided into two phases when ammonia sulfate was added. The complex [SbI4-][C3H7OH2+ ] formed by Sbi4 4(the reaction product of Sb(Ⅲ) with potassium iodide) and protonized n-propyl alcohol (C3H7OH2+) could be fully extracted by n-propyl alcohol phase in phase separation process. When the system contained 0. 40 mol/L potassium iodide, 0. 2 g/Ml ammonia sulfate and 30% n-propyl alcohol (V/V). Sb(Ⅲ) was well separated from Pb(II),Mn(II)tFe(Ⅲ),Zn(Ⅱ), A1(II),Cr(Ⅲ),Ni(II},Cu(Ⅱ) and Mg(II), and the extraction recoveries of Sb(Ⅲ) was over 96. 9%.%研究了在抗坏血酸存在下正丙醇-碘化钾-硫酸铵体系萃取分离和富集Sb(Ⅲ)的行为及与一些金属离子分离的条件.结果表明,硫酸铵能使正丙醇的水溶液分成两相,在分相过程中,Sb(Ⅲ)与碘化钾生成的(SbI4-)与质子化正丙醇(C3 H7 OH2+)形成的缔合物[SbI4][C3 H7 OH2+]能被正丙醇相完全萃取.当正丙醇、碘化钾和硫酸铵的浓度分别为30%(V/V)、0.40 mol/L、0.20 g/mL时,Sb(Ⅲ)的萃取率达到96.9%以上,Pb(Ⅱ),Mn(Ⅱ),Fe(Ⅲ),Zn(Ⅱ),Al(Ⅲ),Cr(Ⅲ),Ni(Ⅱ),Cu(Ⅱ)和Mg(Ⅱ)基本不被萃取,实现了Sb(Ⅲ)与上述金属离子的分离.

  2. 聚乙二醇-硫酸铵双水相体系萃取螺旋藻藻蓝蛋白的研究%The extraction of C-phycocyanin from Spirulina using aqueous two- phase system composed of PEG and ammonium sulfate

    Institute of Scientific and Technical Information of China (English)

    于淑坤; 岳思君; 田露; 苏建宇


    对聚乙二醇一硫酸铵双水相体系直接从螺旋藻破碎液中萃取藻蓝蛋白的技术进行了研究。结果表明,对于藻蓝蛋白含量为0.282mg/mL的螺旋藻细胞破碎液,10%PEG2000与20%的硫酸铵双水相体系萃取藻蓝蛋白的效果最佳,经2次革取,藻蓝蛋白总革取率为96.1,藻蓝蛋白纯度达到1.2。%The technology of extracting C-phycocyanin from Spirulina by using a aqueous two-phase system composed of PEG and ammonium sulfate was studied in this paper. The results showed that the optimum conditions of extraction were 10 percent of PEG2000 and 20 percent of (NH4)2SO4. The total extraction rate of C-phycocyanin was reached to 96.1 percent and the purity of C-phycocyanin was as high as 1.2.

  3. 天然高分子改性异喹啉季铵盐对SRB杀菌性能及机理的研究%A Study of Bactericidal Effect of Natural Polymeric Modified Isoquinoline Quaternary Ammonium Salt on Sulfate Reducing Bacteria(SRB) and Mechanism

    Institute of Scientific and Technical Information of China (English)

    潘碌亭; 肖锦


    The bactericidal effect of natural polymeric modified isoquinoline quaternary ammonium salt(FIQ-C)on sulfate reducing bacteria (SRB) was studied using the vanishing- dilution method. Factors affecting the bactericidal ef- ficiency were investigated, the bectericidal ability of FIQ-C was compared with that of 1227, and the bactericidal mechanism of FIQ-C was approached. The result shows that FIQ - C has a good bactericidal effect on the SRB in sim- ulated oil field waste water and that when the addition of FIQ - C is 5 mg/L, the bactericidal rate may be 99.9% or higher.%采用绝迹稀释法研究了天然高分子改性异喹啉季铵盐(FIQ-C)对硫酸盐还原菌(SRB)的杀灭性能。考察了各种因素对杀菌性能的影响,比较了药剂FIQ-C与1227的杀菌能力,探讨了FIQ-C的杀菌机理。结果表明,药FIQ-C对模拟油田废水中SRB有良好的杀灭性能,当FIQ-C投加量为5 mg/L时,杀菌率可达99.9%以上。

  4. Floatation Sepearation of Palladium with Ammonium Sulfate-potassium Iodide-hexadecyl Trimethylammoniun Bromide System%十六烷基三甲基季铵溴化物-碘化钾-硫酸铵体系浮选分离钯

    Institute of Scientific and Technical Information of China (English)

    翟秋阁; 沈久明; 牛莉红


    The behavior and conditions of floatation separation of palladium from other metal ions in hexadecyl trimethylammonium bromide-potassium iodide-ammonium sulfate system were studied.It showed that Pd2+ can be separated quantitatively from Zn2+ 、Mn2+、Ni2+、 Co2+ 、Fe2+ 、Al3+ 、Cr3+ and Mg2+ by floatation in the given condition.%研究十六烷基三甲基季铵溴化物-碘化钾-硫酸铵体系分离钯的行为及与一些金属离子分离的条件.实验表明,在一定条件下,实现Pd2+与Zn2+、Mn2+、Ni2+、Co2+、Fe2+、Al3+、Cr3++和Mg2+离子的定量分离.

  5. Evaluating Ammonium, Nitrate and Sulfate Aerosols in 3-Dimensions (United States)

    Mezuman, Keren; Bauer, Susanne E.; Tsigaridis, Kostas


    The effect aerosols have on climate and air quality is a func-on of their chemical composi-on, concentra-on and spa-al distribu-on. These parameters are controlled by emissions, heterogeneous and homogeneous chemistry, where thermodynamics plays a key role, transport, which includes stratospheric-­- tropospheric exchange, and deposi-onal sinks. In this work we demonstrate the effect of some of these processes on the SO4-NH4­-NO3 system using the GISS ModelE2 Global Circula-on Model (GCM).

  6. Extraction of beryllium sulfate by a long chain amine; Extraction du sulfate de beryllium par une amine a longue chaine

    Energy Technology Data Exchange (ETDEWEB)

    Etaix, E.S. [Commissariat a l' Energie Atomique, Fontenay-Aux-Roses (France). Centre d' Etudes Nucleaires


    The extraction of sulfuric acid in aqueous solution by a primary amine in benzene solution, 3-9 (diethyl) - 6-amino tri-decane (D.E.T. ) - i.e., with American nomenclature 1-3 (ethyl-pentyl) - 4-ethyl-octyl amine (E.P.O.) - has made it possible to calculate the formation constants of alkyl-ammonium sulfate and acid sulfate. The formula of the beryllium and alkyl-ammonium sulfate complex formed in benzene has next been determined, for various initial acidity of the aqueous solution. Lastly, evidence has been given of negatively charged complexes of beryllium and sulfate in aqueous solution, through the dependence of the aqueous sulfate ions concentration upon beryllium extraction. The formation constant of these anionic complexes has been evaluated. (author) [French] L'etude de l'extraction de l'acide sulfurique en solution aqueuse par une amine primaire en solution dans le benzene, le diethyl-3,9 amino-6 tridecane (D.E.T.) - autre nom americain 1-3 (ethylpentyl) - 4-ethyloctylamine (E.P.O.) a permis de calculer les constantes de formation du sulfate et de l'hydrogenosulfate d'alkyl-ammonium. La formule du complexe de sulfate de beryllium et d'alkyl-ammonium forme en solution benzenique a ete ensuite determinee pour diverses acidites initiales de la solution aqueuse. Enfin, l'influence de la concentration des ions sulfate de la phase aqueuse sur l'extraction du beryllium a mis en evidence la formation en solution aqueuse de complexes anioniques de sulfate et de beryllium dont la constante de formation a ete evaluee. (auteur)

  7. Sulfate inhibition effect on sulfate reducing bacteria

    Directory of Open Access Journals (Sweden)

    Sulaiman Al Zuhair


    Full Text Available There is an increasing interest in the potential of bacterial sulfate reduction as an alternative method for sulfate removal from wastewater. Under anaerobic conditions, sulfate-reducing bacteria (SRB utilize sulfate to oxidize organic compounds and generate sulfide (S2-. SRB were successfully isolated from sludge samples obtained from a local petroleum refinery, and used for sulfate removal. The effects of initial sulfate concentration, temperature and pH on the rate of bacterial growth and anaerobic sulfate removal were investigated and the optimum conditions were identified. The experimental data were used to determine the parameters of two proposed kinetic model, which take into consideration substrate inhibition effect. Keywords: Sulfate Reducing Bacteria, Sulfate, Kinetic Model, Biotreatement, Inhibition Received: 31 August 2008 / Received in revised form: 18 September 2008, Accepted: 18 September 2008 Published online: 28 September 2008

  8. Modeling the Use of Sulfate Additives for Potassium Chloride Destruction in Biomass Combustion

    DEFF Research Database (Denmark)

    Wu, Hao; Pedersen, Morten Nedergaard; Jespersen, Jacob Boll;


    Potassium chloride, KCl, formed from biomass combustion may lead to ash deposition and corrosion problems in boilers. Sulfates are effective additives for converting KCl to the less harmful K2SO4 and HCl. In the present study, the rate constants for decomposition of ammonium sulfate and aluminum...... sulfate were obtained from experiments in a fast heating rate thermogravimetric analyzer. The yields of SO2 and SO3 from the decomposition were investigated in a tube reactor at 600–900 °C, revealing a constant distribution of about 15% SO2 and 85% SO3 from aluminum sulfate decomposition and a temperature......-dependent distribution of SO2 and SO3 from ammonium sulfate decomposition. On the basis of these data as well as earlier results, a detailed chemical kinetic model for sulfation of KCl by a range of sulfate additives was established. Modeling results were compared to biomass combustion experiments in a bubbling...

  9. Global modeling of nitrate and ammonium aerosols using EQSAM3 (United States)

    Xu, L.; Penner, J. E.


    Atmospheric aerosols, particles suspending in air, are important as they affect human health, air quality, and visibility as well as climate. Sulfate, nitrate, ammonium, chloride and sodium are among the most important inorganic aerosol species in the atmosphere. These compounds are hygroscopic and absorb water under almost all ambient environmental conditions. The uptake of water alters the aerosol size, and causes water to become the constituent with the largest atmospheric aerosol mass, especially when the aerosols grow into fog, haze or clouds. Furthermore, several global model studies have demonstrated that rapid increases in nitrogen emissions could produce enough nitrate in aerosols to offset the expected decline in sulfate forcing by 2100 for the extreme IPCC A2 scenario (Bauer et al., 2007). Although nitrate and ammonium were identified as significant anthropogenic sources of aerosols by a number of modeling studies, most global aerosol models still exclude ammonium-nitrate when the direct aerosol forcing is studied. In this study, the computationally efficient equilibrium model, EQSAM3, is incorporated into the UMICH-IMPACT-nitrate model using the hybrid dynamical solution method (Feng and Penner, 2007). The partitioning of nitrate and ammonium along with the corresponding water uptake is evaluated by comparing the model to the EQUISOLVE II method used in Feng and Penner (2007). The model is also evaluated by comparison with the AERONET data base and satellite-based aerosol optical depths.

  10. Physicochemical Study on the Interface Zone of Concrete Exposed to Different Sulfate Solutions

    Institute of Scientific and Technical Information of China (English)


    This paper reports the results of the visual observations and micro-analysis of concrete core samples after 6 and 12 months of their exposure to sodium, ammonium and magnesium sulfate solutions with the same concentration of sulfate ions. XRD, SEM and EDS were used for micro-analysis of the microstructure and the composition of the interface zone in the samples. The results indicate that the deterioration of concrete by different sulfate solutions could proceed differently with regard to the mechanism and the mode of damage caused. The damage of concrete exposed to sodium sulfate solution is mainly caused by the gypsum crystals formed in the interface zone, which lead to expansion and cracking. In the case of concrete immersed in magnesium sulfate solutions, a layer of brucite (magnesium hydroxide) and gypsum was produced in the interface zone, which reduces the cohesiveness of the interface zone in concrete. For the concrete immersed in ammonium sulfate solutions, the conversation of mortar to some mush mass by ammonium ions and the formation of a large of gypsum occurred in the interface zone, consequently, serious softening of hydrated cement pastes and expansion and cracking of concrete are the characteristics of the attack by ammonium sulfate solutions. Also, it is considered that using drilled concrete core as samples to evaluate the sulfate resistance of concrete is a good and accelerated method.

  11. Utilização de uréia em misturas com sulfato de amônio ou com gesso na cultura de milho Use of urea in mix with ammonium sulfate or gypsum in the culture of corn

    Directory of Open Access Journals (Sweden)

    Waldo Alejandro Ruben Lara Cabezas


    ês a quatro folhas e seis a sete folhas. A produtividade de grãos foi similar entre as fontes de U+SA e U+Gesso, sendo em média de 5.332 kg ha-1. Em Uberlândia, foram comparados os cinco tratamentos testados no experimento - safrinha de Votuporanga. As misturas de grânulos foram aplicadas em dose única de 90 kg ha-1 de N, no estádio de quatro a cinco folhas. Os maiores teores de N-mineral total foram detectados na camada de 0 a 10 cm de profundidade, em todos os tratamentos (abaixo de 3 mg dm-3, diminuindo em profundidade, enquanto o S-sulfato concentrou-se entre as camadas de 10 a 60 cm. Os tratamentos de U+Gesso e U+SA apresentaram, em média, produtividades de 11.364 e 10.300 kg ha-1 de grãos, respectivamente. O custo de aplicação de U+Gesso gr foi 27,7 % superior aos custos médios de aplicação de U+SAgr e U+SAfa, devido a seu menor teor de N, e 7,8 % superior em relação aos custos diretos totais por hectare. A mistura NK com aplicação posterior de U+Gesso pó apresentou custo de aplicação similar ao da U+Gesso gr, devido à dupla operação de aplicação do primeiro. Os resultados em ambas as regiões permitem concluir que o milho respondeu de forma similar à aplicação em cobertura das fontes mistas, U+SA e U+Gesso, independentemente da granulometria dos produtos, e que os custos de aplicação das formas U+Gesso foram superiores aos das misturas U+SA.Qualitative and quantitative aspects must be considered in the side-dressing fertilization in the cultivation of corn. This study aimed to evaluate in the counties of Votuporanga (SP and Uberlândia (MG, the effect on productivity of corn using different mixtures of granules in the side-dressing fertilization, containing nitrogen (N and sulphur (S. In Votuporanga (SP, in an Argisol (120 g kg-1 of clay were estimated losses through volatilization of NH3-N granules mix consisting of urea (U + ammonium sulfate (AS or U + Gypsum applied in the first split of nitrogen application. In Uberlândia (MG

  12. Ammonium diphosphitoindate(III

    Directory of Open Access Journals (Sweden)

    Farida Hamchaoui


    Full Text Available The crystal structure of the title compound, NH4[In(HPO32], 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(HPO32]− 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(HPO32]− 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.

  13. Waterproofing Materials for Ammonium Nitrate

    Directory of Open Access Journals (Sweden)

    R.S. Damse


    Full Text Available This study explores the possibility of overcoming the problem of hygroscopicity of ammonium nitrate by coating the particles with selected waterproofing materials. Gravimetric analysis ofthe samples of ammonium nitrate coated with eight different waterproofing materials, vis-a-vis, uncoated ammonium nitrate, were conducted at different relative humidity and exposuretime. The results indicate that mineral jelly is the promising waterproofing material for ammonium nitrate among the materials tested, viz, calcium stearate, dioctyl phthalate, kaoline, diethylphthalate, dinitrotoluene, shelac varnish, and beeswax. Attempts were made to confirm the waterproofing ability of mineral jelly to ammonium nitrate using differential thermal analysisand x-ray diffraction patterns as an experimental tool. Suitability of mineral jelly as an additive for the gun propellant was also assessed on the basis of theoretical calculations using THERMprogram.

  14. Efeito da calagem e sulfato de amônio no algodão: II - Concentração de cátions e ânions na solução do solo e absorção de nutrientes pelas plantas Effect of liming and ammonium sulfate in cotton: II - Concentration of cations and anions in the soil solution and plant nutrient uptake

    Directory of Open Access Journals (Sweden)

    José Salvador Simoneti Foloni


    soil mobilization. Nitrogen fertilization adds anions that can increase the solubility of basic cations of the soil due to formation of ionic pairs. The objective of this study was to characterize the dynamics of anions (SO4(2- and NO3- and cations (NH4+, Ca2+, Mg2+ and K+ in the soil solution, and the nutrient uptake by cotton plants subjected to different lime application forms and ammonium sulfate fertilization, with straw on the soil surface. Cotton plants (Gossypium hirsutum were grown for 60 days in PVC columns filled with a distroferric Red Latosol (sand loam Rhodic Oxisol. The soil had lime incorporated into the 0-20 cm layer, liming on the soil surface, or received no lime. Nitrogen was used at rates of 0, 50, 100 and 150 kg ha-1 as ammonium sulfate. The pots consisted of PVC columns of 20 cm diameter and 50 cm height, totaling 15.71 dm³. Porous capsules were installed at a depth of 15-20 cm to extract soil solution. The SO4(2- of the soil solution was increased by the nitrogen fertilization, independently of the lime application form. Nitrification was favored in the short-term with the application of ammonium sulfate only in the condition of incorporated lime. After 50 days of plant growth, however, nitrate in the soil solution increased, even in the soil that had not been limed. The Ca, Mg and K concentrations in the soil solution were increased as a response to the nitrogen top dressing. The anion SO4(2- presented greater affinity than NO3- in the formation of ionic pairs with the basic cations in the soil solution. The application of ammonium sulfate was most effective in promoting Ca and Mg uptake by the cotton plants when lime was incorporated.

  15. Relations of ammonium minerals at several hydrothermal systems in the western U.S. (United States)

    Krohn, M. Dennis; Kendall, Carol; Evans, John R.; Fries, Terry L.


    Ammonium bound to silicate and sulfate minerals has recently been located at several major hydrothermal systems in the western U.S. utilizing newly-discovered near-infrared spectral properties. Knowledge of the origin and mineralogic relations of ammonium minerals at known hydrothermal systems is critical for the proper interpretation of remote sensing data and for testing of possible links to mineralization. Submicroscopic analysis of ammonium minerals from two mercury- and gold-bearing hot-springs deposits at Ivanhoe, Nevada and McLaughlin, California shows that the ammonium feldspar, buddingtonite, occurs as fine-grained euhedral crystals coating larger sulfide and quartz crystals. Ammonium feldspar seems to precipitate relatively late in the crystallization sequence and shows evidence for replacement of NH 4 + by K + or other monovalent cations. Some buddingtonite is observed in close association with mercury, but not with gold. Ammonioalunite is found in a variety of isolated crystal forms at both deposits. Nitrogen isotopic values for ammonium-bearing minerals show a 14‰ range in composition, precluding assignment of a specific provenance to the nitrogen. The correlations of nitrogen isotopic values with depth and ammonium content suggest some loss of nitrogen in the oxidizing supergene environment, possibly as a metastable mineral. The high ammonium content in these hydrothermal systems, the close association to mercury, and the small crystal size of the ammonium-bearing minerals all suggest that ammonium may be transported in a late-stage vapor phase or as an organic volatile. Such a process could lead to the formation of a non-carbonaceous organic aureole above a buried geothermal source. The discovery of a 10-km outcrop of ammonium minerals confirms that significant substitution of ammonium in minerals is possible over an extensive area and that remote sensing is a feasible means to detect such aureoles.

  16. Ammonium Perchlorate and Ammonium Perchlorate- Hydroxyl Terminated Polybutadiene Simulated Combustion

    Directory of Open Access Journals (Sweden)

    Rene Francisco Boschi Gonçalves


    Full Text Available The combustion simulation of ammonium perchlorate was carried out with the software Chemkin, in two steps: the burning behavior of pure ammonium perchlorate and the one of formulated ammonium perchlorate with hydroxyl terminated polybutadiene binder. In both cases, the room pressure varied in order to verify its influence in the system. The burning environment conditions were diverse. During the combustion process, the data obtained from the kinetic chemistry simulation software were compiled. The flame structure can be described by the molar fraction of the burning products and the temperature evolution from the surface of the material.

  17. Recent results of EPR and Moessbauer investigations on lattice dynamics in ammonium sulphate

    CERN Document Server

    Grecu, M N; Grecu, V V


    Recent results of the lattice dynamics investigation on ammonium sulfate are reported based on recent experiments carried out using using the non-destructive experimental technique of EPR and NGR. The main results confirm the presence and the contribution of a soft mode, which accompanied the paraferroelectric phase transition in the investigated crystal. (authors)

  18. Particle size distribution and behavior of sulfate aerosols in a coastal region

    Energy Technology Data Exchange (ETDEWEB)

    Fujimura, M.; Hashimoto, Y.


    To obtain fundamental knowledge about sulfate aerosols, a field research was conducted in a coastal region distant from industrial pollution sources. The aerosol samples were analyzed for some elements, sulfate and ammonium ions. Sulfate was determined by the turbidimetry with 2-aminoperimidine, and ammonium was by the colorimetry of indophenol method. Trace elements with short-lived nuclides were analyzed by instrumental neutron activation analysis. The mass-size distribution curve of total aerosols was the general bimodal pattern, although the concentration level was very low. Most of sulfate and ammonium salts were distributed in the fine particle range less than 2 microns in aerodynamic diameter, but sulfate had another peak, thought to be of maritime origin, in the coarse particle range. Nevertheless, many fine sulfate particles that had been produced secondarily in the atmosphere were found in such a less polluted coastal region. The change of the sulfate concentrations obtained by the two-stage Andersen type sampler showed a correlation with the humidity. This may suggest that the formation of sulfate aerosols from sulfur dioxide could be related to a catalytic oxidation process in water drops.

  19. Parameterization of the Optical Properties of Sulfate Aerosols. (United States)

    Li, J.; Wong, J. G. D.; Dobbie, J. S.; Chýlek, P.


    Parameterizations of the shortwave optical properties of ammonium sulfate [(NH4)2SO4], ammonium bisulfate (NH4HSO4), and sulfuric acid (H2SO4) are provided as functions of relative humidity for high and low spectral resolution band models. The optical property parameterization is simple in form and in its dependence on relative humidity. The growth of the aerosol particles is based on equilibrium saturation theory, and the optical properties are computed from Mie theory. The optical properties necessary for the most commonly used radiative transfer methods are provided.Results show that when relative humidity effects are included in the backscatter fraction the radiative forcing is found to be a more sensitive function of near infrared wavelengths compared to visible wavelengths. For increasing relative humidity, sulfuric acid is found to have a larger effect on radiative forcing compared to the forcing by ammonium sulfate or ammonium bisulfate. Also, as relative humidity increases, forcing increases to higher values for smaller mode size distributions compared to forcing by larger mode distributions. These parameterizations will enable climate forcing studies to be performed with radiative transfer schemes that more accurately represent sulfate influences on the radiation balance.

  20. 21 CFR 184.1138 - Ammonium chloride. (United States)


    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ammonium chloride. 184.1138 Section 184.1138 Food... Specific Substances Affirmed as 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....

  1. 21 CFR 184.1133 - Ammonium alginate. (United States)


    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ammonium alginate. 184.1133 Section 184.1133 Food... Specific Substances Affirmed as GRAS § 184.1133 Ammonium alginate. (a) Ammonium alginate (CAS Reg. No. 9005.... Ammonium alginate is prepared by the neutralization of purified alginic acid with appropriate pH...

  2. Tyrosine Sulfation of Statherin

    Directory of Open Access Journals (Sweden)

    C. Kasinathan, N. Gandhi, P. Ramaprasad, P. Sundaram, N. Ramasubbu


    Full Text Available Tyrosylprotein sulfotransferase (TPST, responsible for the sulfation of a variety of secretory and membrane proteins, has been identified and characterized in submandibular salivary glands (William et al. Arch Biochem Biophys 1997; 338: 90-96. In the present study we demonstrate the sulfation of a salivary secretory protein, statherin, by the tyrosylprotein sulfotransferase present in human saliva. Optimum statherin sulfation was observed at pH 6.5 and at 20 mm MnCl2. Increase in the level of total sulfation was observed with increasing statherin concentration. The Km value of tyrosylprotein sulfotransferase for statherin was 40 μM. Analysis of the sulfated statherin product on SDS-polyacrylamide gel electrophoresis followed by autoradiography revealed 35S-labelling of a 5 kDa statherin. Further analysis of the sulfated statherin revealed the sulfation on tyrosyl residue. This study is the first report demonstrating tyrosine sulfation of a salivary secretory protein. The implications of this sulfation of statherin in hydroxyapatite binding and Actinomyces viscosus interactions are discussed.

  3. Diammonium tricadmium tris(sulfate dihydroxide dihydrate

    Directory of Open Access Journals (Sweden)

    Xin Yin


    Full Text Available The title compound, (NH42Cd3(SO43(OH2(H2O2, has been obtained serendipitously. It is isotypic with the heavier alkali analogues M2Cd3(SO43(OH2(H2O2 (M = K, Rb, Cs. The structure contains two Cd2+ ions, one in a general position and one with site symmetry m. The former Cd2+ ion is coordinated by three O atoms of three SO4 groups, two hydroxide O atoms and one water O atom, the latter Cd2+ ion by four O atoms of four SO4 groups and two hydroxide O atoms, both in a distorted octahedral coordination geometry. This arrangement leads to the formation of a layered framework extending parallel to (100, with the ammonium cations situated in the voids. O—H...O hydrogen bonds involving the water molecules, hydroxide groups and sulfate O atoms, as well as N—H...O hydrogen bonds between ammonium cations and sulfate O atoms consolidate the crystal packing.

  4. Characterization of alumina obtained from the synthesis of gelatinous precipitates of aluminum hydroxide obtained from the reaction of aluminum sulfate and ammonium hydroxide in different temperatures; Caracterizacao de aluminas obtidas a partir da sintese de precipitados gelatinosos de hidroxido de aluminio obtidos pela reacao de sulfato de aluminio e hidroxido de amonio em diferentes temperaturas

    Energy Technology Data Exchange (ETDEWEB)

    Mercury, Jose Manuel Rivas [Centro Federal de Educacao Tecnologica do Maranhao (CEFET), Sao Luiz, MA (Brazil); Freitas Neves, R. de [Para Univ., Belem, Pa (Brazil). Dept. de Engenharia Quimica


    Aluminum hydroxide was obtained by synthesis through neutralization of solutions aluminum sulphate solutions with ammonium hydroxide at different level of temperatures of synthesis (30, 60, 90 deg C) on the molar [OH]/[Al{sup +3}] of 6,5. All products was burned at 950 deg C during two hours of dried aluminum hydroxide powder. Alumina obtained and A-16SG, APC-2011, produced by Alcoa Co. was characterized by Bulk Density, Tap density, Real Density, Particle Size Distribution, X-Ray Diffractions and Chemical Analysis and both compared. (author) 11 refs., 3 figs., 3 tabs.

  5. Roles of heparan sulfate sulfation in dentinogenesis. (United States)

    Hayano, Satoru; Kurosaka, Hiroshi; Yanagita, Takeshi; Kalus, Ina; Milz, Fabian; Ishihara, Yoshihito; Islam, Md Nurul; Kawanabe, Noriaki; Saito, Masahiro; Kamioka, Hiroshi; Adachi, Taiji; Dierks, Thomas; Yamashiro, Takashi


    Cell surface heparan sulfate (HS) is an essential regulator of cell signaling and development. HS traps signaling molecules, like Wnt in the glycosaminoglycan side chains of HS proteoglycans (HSPGs), and regulates their functions. Endosulfatases Sulf1 and Sulf2 are secreted at the cell surface to selectively remove 6-O-sulfate groups from HSPGs, thereby modifying the affinity of cell surface HSPGs for its ligands. This study provides molecular evidence for the functional roles of HSPG sulfation and desulfation in dentinogenesis. We show that odontogenic cells are highly sulfated on the cell surface and become desulfated during their differentiation to odontoblasts, which produce tooth dentin. Sulf1/Sulf2 double null mutant mice exhibit a thin dentin matrix and short roots combined with reduced expression of dentin sialophosphoprotein (Dspp) mRNA, encoding a dentin-specific extracellular matrix precursor protein, whereas single Sulf mutants do not show such defective phenotypes. In odontoblast cell lines, Dspp mRNA expression is potentiated by the activation of the Wnt canonical signaling pathway. In addition, pharmacological interference with HS sulfation promotes Dspp mRNA expression through activation of Wnt signaling. On the contrary, the silencing of Sulf suppresses the Wnt signaling pathway and subsequently Dspp mRNA expression. We also show that Wnt10a protein binds to cell surface HSPGs in odontoblasts, and interference with HS sulfation decreases the binding affinity of Wnt10a for HSPGs, which facilitates the binding of Wnt10a to its receptor and potentiates the Wnt signaling pathway, thereby up-regulating Dspp mRNA expression. These results demonstrate that Sulf-mediated desulfation of cellular HSPGs is an important modification that is critical for the activation of the Wnt signaling in odontoblasts and for production of the dentin matrix.

  6. 21 CFR 582.1141 - Ammonium phosphate. (United States)


    ... 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)...

  7. 76 FR 46907 - Ammonium Nitrate Security Program (United States)


    ... and fertilizer blends containing more than 15% by weight ammonium nitrate, except liquid fertilizers... concerning the detonability of ammonium nitrate; Comments on how likely ammonium nitrate fertilizer users would be to use an alternative fertilizer that is potentially less detonable, such as Sulf-N...

  8. 76 FR 11273 - Ammonium Nitrate From Russia (United States)


    ... COMMISSION Ammonium Nitrate From Russia AGENCY: United States International Trade Commission. ACTION: Institution of a five-year review concerning the suspended investigation on ammonium nitrate from Russia... investigation on ammonium nitrate from Russia would be likely to lead to continuation or recurrence of...

  9. 76 FR 47238 - Ammonium Nitrate From Russia (United States)


    ... COMMISSION Ammonium Nitrate From Russia Determination On the basis of the record \\1\\ developed in the subject... order on ammonium nitrate from Russia would be likely to lead to continuation or recurrence of material... Commission are contained in USITC Publication 4249 (August 2011), entitled Ammonium Nitrate from...

  10. 21 CFR 582.7133 - Ammonium alginate. (United States)


    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ammonium alginate. 582.7133 Section 582.7133 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Ammonium alginate. (a) Product. Ammonium alginate. (b) Conditions of use. This substance is...

  11. Application of Neesler reagent in the ammonium quantification used in the fermentations of biotechnology products

    Directory of Open Access Journals (Sweden)

    Dinorah Torres-Idavoy


    Full Text Available The ammonium salts are used in fermentations to supplement the deficient amounts of nitrogen and stabilize the pH of the culture medium. The excess ammonium ion exerts a detrimental effect on the fermentation process inhibiting microbial growth. An analytical method based on Neesler reagent was developed for monitoring and controlling the concentration of ammonium during the fermentation process. The test was standardized, by means of the selection of measuring equipment, and the reaction time as well as comparing standards of ammonium salts. The method was characterized with the evaluation of the next parameters: Specificity, Linearity and Range, Quantification Limit, Accuracy and Precision. The method proved to be specific. Two linear curves were defined in the ranges of concentrations of ammonium chloride salt (2-20 μg/ml and ammonium sulfate salt (5-30 μg/ml. The limits of quantification were the lowest points of each one. The method proved to be accurate and precise. This assay was applied to samples of the yeast culture and bacteria of the genus Saccharomyces and E. coli respectively. A novel method in micro plate for quantification and analytical control of ammonia was developed. This method is used to control this fundamental chemical component in the fermentations, to optimize the culture medium. Thus, an appropriate expression of recombinant proteins and proper vaccine candidates for clinical use are achieved

  12. Phase diagram of ammonium nitrate (United States)

    Dunuwille, M.; Yoo, C. S.


    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.

  13. Modes in the size distributions and neutralization extent of fog-processed ammonium salt aerosols observed at Canadian rural locations

    Directory of Open Access Journals (Sweden)

    X. H. Yao


    Full Text Available Among the 192 samples of size-segregated water-soluble inorganic ions collected using a Micro-Orifice Uniform Deposit Impactor (MOUDI at eight rural locations in Canada, ten samples were identified to have gone through fog processing. The supermicron particle modes of ammonium salt aerosols were found to be the fingerprint of fog processed aerosols. However, the patterns and the sizes of the supermicron modes varied with ambient temperature (T and particle acidity and also differed between inland and coastal locations. Under T > 0 °C condition, fog-processed ammonium salt aerosols were completely neutralized and had a dominant mode at 1–2 μm and a minor mode at 5–10 μm if particles were in neutral condition, and ammonium sulfate was incompletely neutralized and only had a 1–2 μm mode if particles were in acidic conditions. Under T < 0 °C at the coastal site, fog-processed aerosols exhibited a bi-modal size distribution with a dominant mode of incompletely-neutralized ammonium sulfate at about 3 μm and a minor mode of completely-neutralized ammonium sulfate at 8–9 μm. Under T < 0 °C condition at the inland sites, fog-processed ammonium salt aerosols were sometimes completely neutralized and sometimes incompletely neutralized, and the size of the supermicron mode was in the range from 1 to 5 μm. Overall, fog-processed ammonium salt aerosols under T < 0 °C condition were generally distributed at larger size (e.g., 2–5 μm than those under T > 0 °C condition (e.g., 1–2 μm.

  14. Obtaining of barium sulfate from solution formed after desulfation of the active mass of scrap lead-acid batteries

    Directory of Open Access Journals (Sweden)

    O. A. Kalko


    Full Text Available Analyses of literature data about processes for solution utilization formed after desulfation of the active mass of scrap lead-acid batteries is performed. Optimal conditions for obtaining of barium sulfate sediment from ammonium sulfate solute and chemically pure Ba(OH2×8H2O и BaCl2×2H2O were found experimentally. In laboratory the commercial barium sulfate from sulfate solutions, that are waste of recycling process of battery scrap, with application of chloride and barium hydroxide was production. The possibility of using this product were discussed.

  15. Synthesis of Chitosan Quaternary Ammonium Salts

    Institute of Scientific and Technical Information of China (English)


    A series of N-alkyl or N-aryl chitosan quaternary ammonium salts were prepared via Schiffs base intermediates. Quaternization of N-substituted chitosan derivatives was carried out using methyl iodide to produce water-soluble cationic chitosan quaternary ammonium salt. The products were characterized by IR, 1HNMR and elemental analysis. The degree of substitution of chitosan quaternary ammonium salt was calculated by elemental analysis.

  16. Effect of ammonium sulfate, ammonium chloride and root-zone acidity on inorganic ion content of tobacco (United States)

    Vessey, J. K.; Raper, C. D. Jr; Henry, L. T.; Raper CD, J. r. (Principal Investigator)


    Tobacco plants (Nicotiana tabacum L. cv NC82) were supplied with (NH4)2SO4 or NH4Cl at root-zone pH of 6.0 and 4.5 in hydroponic culture for 28 days. Dry matter accumulation, total N and C content, and leaf area and number were not affected by the NH4+ source or root-zone pH. Plants supplied with NH4Cl accumulated up to 1.2 mM Cl g DW-1, but accumulated 37% less inorganic H2PO4- and 47% less SO4(2-) than plants supplied with (NH4)2SO4. The large Cl- accumulation resulted in NH4Cl- supplied plants having a 31% higher inorganic anion (NO3-, H2, PO4-, SO4(2-), and Cl-) charge. This higher inorganic anion charge in the NH4Cl-supplied plants was balanced by a similar increase in K+ charge. Plants supplied with NH4Cl accumulated greater concentrations of Cl- in leaves (up to 5.1% of DW) than plants supplied with (NH4)2SO4 (less than -% DW). Despite the high Cl- concentration of leaves in NH4Cl supplied plants, these plants showed no symptoms of Cl- toxicity. This demonstrates that toxicity symptoms are not due solely to an interaction between high Cl- concentration in tissue and NH4+ nutrition. The increase in root-zone acidity to pH 4.5 from 6.0 did not induce toxicity symptoms.

  17. 49 CFR 176.410 - Division 1.5 materials, ammonium nitrate and ammonium nitrate mixtures. (United States)


    ... 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...

  18. 33 CFR 126.28 - Ammonium nitrate, ammonium nitrate fertilizers, fertilizer mixtures, or nitro carbo nitrate... (United States)


    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Ammonium nitrate, ammonium nitrate fertilizers, fertilizer mixtures, or nitro carbo nitrate; general provisions. 126.28 Section 126...) WATERFRONT FACILITIES HANDLING OF DANGEROUS CARGO AT WATERFRONT FACILITIES § 126.28 Ammonium...

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

    Energy Technology Data Exchange (ETDEWEB)

    Jama, M.A.; Yuecel, H. (Middle East Technical Univ., Ankara (Turkey))


    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+}.

  20. Biodegradation of rocket propellant waste, ammonium perchlorate (United States)

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


    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.

  1. Atmospheric concentrations of ammonia and ammonium at an agricultural site in the southeast United States (United States)

    Robarge, Wayne P.; Walker, John T.; McCulloch, Ronald B.; Murray, George

    In this study, we present ˜1 yr (October 1998-September 1999) of 12-hour mean ammonia (NH 3), ammonium (NH 4+), hydrochloric acid (HCl), chloride (Cl -), nitrate (NO 3-), nitric acid (HNO 3), nitrous acid (HONO), sulfate (SO 42-), and sulfur dioxide (SO 2) concentrations measured at an agricultural site in North Carolina's Coastal Plain region. Mean gas concentrations were 0.46, 1.21, 0.54, 5.55, and 4.15 μg m -3 for HCl, HNO 3, HONO, NH 3, and SO 2, respectively. Mean aerosol concentrations were 1.44, 1.23, 0.08, and 3.37 μg m -3 for NH 4+, NO 3-, Cl -, and SO 42-, respectively. Ammonia, NH 4+, HNO 3, and SO 42- exhibit higher concentrations during the summer, while higher SO 2 concentrations occur during winter. A meteorology-based multivariate regression model using temperature, wind speed, and wind direction explains 76% of the variation in 12-hour mean NH 3 concentrations ( n=601). Ammonia concentration increases exponentially with temperature, which explains the majority of variation (54%) in 12-hour mean NH 3 concentrations. Dependence of NH 3 concentration on wind direction suggests a local source influence. Ammonia accounts for >70% of NH x (NH x=NH 3+NH 4+) during all seasons. Ammonium nitrate and sulfate aerosol formation does not appear to be NH 3 limited. Sulfate is primarily associated ammonium sulfate, rather than bisulfate, except during the winter when the ratio of NO 3--NH 4+ is ˜0.66. The annual average NO 3--NH 4+ ratio is ˜0.25.

  2. Direct Sulfation of Limestone

    DEFF Research Database (Denmark)

    Hu, Guilin; Dam-Johansen, Kim; Wedel, Stig


    -state diffusion. The nucleation and crystal grain growth of the solid product, and this mixed control mechanism provide satisfactory explanations of the various phenomena related to the direct sulfation of limestone, such as porosity in the product layer, the variation of the apparent reaction orders of SO2, O-2...

  3. Effects of ammonium concentration and charge exchange on ammonium recovery from high strength wastewater using a microbial fuel cell

    NARCIS (Netherlands)

    Kuntke, P.; Geleij, M.; Bruning, H.; Zeeman, G.; Hamelers, H.V.M.; Buisman, C.J.N.


    Ammonium recovery using a 2 chamber microbial fuel cell (MFC) was investigated at high ammonium concentration. Increasing the ammonium concentration (from 0.07 g to 4 g ammonium-nitrogen/L) by addition of ammonium chloride did not affect the performance of the MFC. The obtained current densities by

  4. 49 CFR 176.415 - Permit requirements for Division 1.5, ammonium nitrates, and certain ammonium nitrate fertilizers. (United States)


    ... 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...

  5. The nucleation kinetics of ammonium metavanadate precipitated by ammonium chloride (United States)

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


    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.

  6. Impact of sulfate pollution on anaerobic biogeochemical cycles in a wetland sediment. (United States)

    Baldwin, Darren S; Mitchell, Alison


    The impact of sulfate pollution is increasingly being seen as an issue in the management of inland aquatic ecosystems. In this study we use sediment slurry experiments to explore the addition of sulfate, with or without added carbon, on the anaerobic biogeochemical cycles in a wetland sediment that previously had not been exposed to high levels of sulfate. Specifically we looked at the cycling of S (sulfate, dissolved and particulate sulfide--the latter measured as acid volatile sulfide; AVS), C (carbon dioxide, bicarbonate, methane and the short chain volatile fatty acids formate, acetate, butyrate and propionate), N (dinitrogen, ammonium, nitrate and nitrite) and redox active metals (Fe(II) and Mn(II)). Sulfate had the largest effects on the cycling of S and C. All the added S at lower loadings were converted to AVS over the course of the experiment (30 days). At the highest loading (8 mmol) less than 50% of consumed S was converted to AVS, however this is believed to be a kinetic effect. Although sulfate reduction was occurring in sediments with added sulfate, dissolved sulfide concentrations remained low throughout the study. Sulfate addition affected methanogenesis. In the absence of added carbon, addition of sulfate, even at a loading of 1 mmol, resulted in a halving of methane formation. The initial rate of formation of methane was not affected by sulfate if additional carbon was added to the sediment. However, there was evidence for anaerobic methane oxidation in those sediments with added sulfate and carbon, but not in those sediments treated only with carbon. Surprisingly, sulfate addition had little apparent impact on N dynamics; previous studies have shown that sulfide can inhibit denitrification and stimulate dissimilatory nitrate reduction to ammonia. We propose that because most of the reduced sulfur was in particulate form, levels of dissolved sulfide were too low to interfere with the N cycle.

  7. Heparan sulfate biosynthesis

    DEFF Research Database (Denmark)

    Multhaupt, Hinke A B; Couchman, John R


    that the synthesis of heparan sulfate is tightly controlled. Although genomics has identified the enzymes involved in glycosaminoglycan synthesis in a number of vertebrates and invertebrates, the regulation of the process is not understood. Moreover, the localization of the various enzymes in the Golgi apparatus has...... not been carried out in a detailed way using high-resolution microscopy. We have begun this process, using well-known markers for the various Golgi compartments, coupled with the use of characterized antibodies and cDNA expression. Laser scanning confocal microscopy coupled with line scanning provides high......-quality resolution of the distribution of enzymes. The EXT2 protein, which when combined as heterodimers with EXT1 comprises the major polymerase in heparan sulfate synthesis, has been studied in depth. All the data are consistent with a cis-Golgi distribution and provide a starting point to establish whether all...

  8. Controlling barium sulfate

    Energy Technology Data Exchange (ETDEWEB)

    Greenley, R.

    Even though for several years success has been realized in controlling barium sulfate scale deposition in relatively shallow, low pressure oil wells--by squeezing an organic phosphonate scale inhibitor into the producing zone--barium sulfate scale depositon in deep, high pressure/high temperature wells usually meant an expensive workover operation. A case history of a deep (16,000 ft) well in St. Mary Parish, Louisiana, and the scale inhibitor squeeze operation are described. Based on the successful results obtained in treating this well, a generalized treating procedure for combating downhole scale deposition in high pressure/high temperature gas wells is presented. Formation squeezing with such an inhibitor represents a significant breakthrough for the oil and gas industry.

  9. Substrate specificity of Rhbg: ammonium and methyl ammonium transport. (United States)

    Nakhoul, Nazih L; Abdulnour-Nakhoul, Solange M; Boulpaep, Emile L; Rabon, Edd; Schmidt, Eric; Hamm, L Lee


    Rhbg is a nonerythroid membrane glycoprotein belonging to the Rh antigen family. In the kidney, Rhbg is expressed at the basolateral membrane of intercalated cells of the distal nephron and is involved in NH4+ transport. We investigated the substrate specificity of Rhbg by comparing transport of NH3/NH4+ with that of methyl amine (hydrochloride) (MA/MA+), often used to replace NH3/NH4+, in oocytes expressing Rhbg. Methyl amine (HCl) in solution exists as neutral methyl amine (MA) in equilibrium with the protonated methyl ammonium (MA+). To assess transport, we used ion-selective microelectrodes and voltage-clamp experiments to measure NH3/NH4+- and MA/MA+-induced intracellular pH (pH(i)) changes and whole cell currents. Our data showed that in Rhbg oocytes, NH3/NH4+ caused an inward current and decrease in pH(i) consistent with electrogenic NH4+ transport. These changes were significantly larger than in H2O-injected oocytes. The NH3/NH4+-induced current was not inhibited in the presence of barium or in the absence of Na+. In Rhbg oocytes, MA/MA+ caused an inward current but an increase (rather than a decrease) in pH(i). MA/MA+ did not cause any changes in H2O-injected oocytes. The MA/MA+-induced current and pH(i) increase were saturated at higher concentrations of MA/MA+. Amiloride inhibited MA/MA+-induced current and the increase in pH(i) in oocytes expressing Rhbg but had no effect on control oocytes. These results indicate that MA/MA+ is transported by Rhbg but differently than NH3/NH4+. The protonated MA+ is likely a direct substrate whose transport resembles that of NH4+. Transport of electroneutral MA is also enhanced by expression of Rhbg.

  10. Ammonium deficiency caused by heterogeneous reactions during a super Asian dust episode (United States)

    Hsu, Shih-Chieh; Lee, Celine Siu Lan; Huh, Chih-An; Shaheen, Robina; Lin, Fei-Jan; Liu, Shaw Chen; Liang, Mao-Chang; Tao, Jun


    Mineral dust particles exert profound impacts on air quality, visibility, and ocean biogeochemistry. Interactions between dust particles and other anthropogenic pollutants modify not only the size spectrum and morphology but also physicochemical properties of dust particles, thereby affecting their radiative properties and ability to act as cloud condensation nuclei and in turn their impact on climate. Here we report field observations on the surface chemical transformations in a super Asian dust plume captured in coastal areas of China and the adjacent marginal seas. The dust plume showed enhanced concentrations of sulfate, nitrate, and calcium along with a decrease in ammonium. The percentages of total Ca in water-soluble form increased from an intrinsic value of ~5% to 25-40% at four stations along the path of the dust plume. From these increases, we estimated the extent to which carbonate was modified by heterogeneous reactions and calculated that the enhanced sulfate and nitrate could account for 40-60% of the observed concentrations. Our observation suggests that the formation of ammonium sulfate via the H2SO4-NH3-H2O ternary system was impeded by heterogeneous reactions in the marine boundary layer when dust loads exceeded a certain threshold. A conceptual model is proposed to elucidate the heterogeneous reactions during the super Asian dust event and their impacts on atmospheric chemistry.

  11. Sulfation of chondroitin. Specificity, degree of sulfation, and detergent effects with 4-sulfating and 6-sulfating microsomal systems

    Energy Technology Data Exchange (ETDEWEB)

    Sugumaran, G.; Silbert, J.E.


    Microsomal preparations from chondroitin 6-sulfate-producing chick embryo epiphyseal cartilage, and from chondroitin 4-sulfate-producing mouse mastocytoma cells, were incubated with UDP-(14C)glucuronic acid and UDP-N-acetylgalactosamine to form non-sulfated proteo(14C)chondroitin. Aliquots of the incubations were then incubated with 3'-phosphoadenylylphosphosulfate (PAPS) in the presence or absence of various detergents. In the absence of detergents, there was good sulfation of this endogenous proteo(14C)chondroitin by the original microsomes from both sources. Detergents, with the exception of Triton X-100, markedly inhibited sulfation in the mast cell system but not in the chick cartilage system. These results indicate that sulfation and polymerization are closely linked on cell membranes and that in some cases this organization can be disrupted by detergents. When aliquots of the original incubation were heat inactivated, and then reincubated with new microsomes from chick cartilage and/or mouse mastocytoma cells plus PAPS, there was no significant sulfation of this exogenous proteo(14C) chondroitin with either system unless Triton X-100 was added. Sulfation of exogenous chondroitin and chondroitin hexasaccharide was compared with sulfation of endogenous and exogenous proteo(14C)chondroitin. Sulfate incorporation into hexasaccharide and chondroitin decreased as their concentrations (based on uronic acid) approached that of the proteo(14C)chondroitin. At the same time, the degree of sulfation in percent of substituted hexosamine increased. However, the degree of sulfation did not reach that of the endogenous proteo(14C)chondroitin. Hexasaccharide and chondroitin sulfation were stimulated by the presence of Triton X-100. However, in contrast to the exogenous proteo(14C)chondroitin, there was some sulfation of hexasaccharide and chondroitin in the absence of this detergent.

  12. Off limits: sulfate below the sulfate-methane transition (United States)

    Brunner, Benjamin; Arnold, Gail; Røy, Hans; Müller, Inigo; Jørgensen, Bo


    One of the most intriguing recent discoveries in biogeochemistry is the ubiquity of cryptic sulfur cycling. From subglacial lakes to marine oxygen minimum zones, and in marine sediments, cryptic sulfur cycling - the simultaneous sulfate consumption and production - has been observed. Though this process does not leave an imprint in the sulfur budget of the ambient environment - thus the term cryptic - it may have a massive impact on other element cycles and fundamentally change our understanding of biogeochemical processes in the subsurface. Classically, the sulfate-methane transition (SMT) in marine sediments is considered to be the boundary that delimits sulfate reduction from methanogenesis as the predominant terminal pathway of organic matter mineralization. Two sediment cores from Aarhus Bay, Denmark reveal the constant presence of sulfate (generally 0.1 to 0.2 mM) below the SMT. The sulfur and oxygen isotope signature of this deep sulfate (34S = 18.9‰, 18O = 7.7‰) was close to the isotope signature of bottom-seawater collected from the sampling site (34S = 19.8‰, 18O = 7.3‰). In one of the cores, oxygen isotope values of sulfate at the transition from the base of the SMT to the deep sulfate pool (18O = 4.5‰ to 6.8‰) were distinctly lighter than the deep sulfate pool. Our findings are consistent with a scenario where sulfate enriched in 34S and 18O is removed at the base of the SMT and replaced with isotopically light sulfate below. Here, we explore scenarios that explain this observation, ranging from sampling artifacts, such as contamination with seawater or auto-oxidation of sulfide - to the potential of sulfate generation in a section of the sediment column where sulfate is expected to be absent which enables reductive sulfur cycling, creating the conditions under which sulfate respiration can persist in the methanic zone.

  13. High aerosol acidity despite declining atmospheric sulfate concentrations over the past 15 years (United States)

    Weber, Rodney J.; Guo, Hongyu; Russell, Armistead G.; Nenes, Athanasios


    Particle acidity affects aerosol concentrations, chemical composition and toxicity. Sulfate is often the main acid component of aerosols, and largely determines the acidity of fine particles under 2.5 μm in diameter, PM2.5. Over the past 15 years, atmospheric sulfate concentrations in the southeastern United States have decreased by 70%, whereas ammonia concentrations have been steady. Similar trends are occurring in many regions globally. Aerosol ammonium nitrate concentrations were assumed to increase to compensate for decreasing sulfate, which would result from increasing neutrality. Here we use observed gas and aerosol composition, humidity, and temperature data collected at a rural southeastern US site in June and July 2013 (ref. ), and a thermodynamic model that predicts pH and the gas-particle equilibrium concentrations of inorganic species from the observations to show that PM2.5 at the site is acidic. pH buffering by partitioning of ammonia between the gas and particle phases produced a relatively constant particle pH of 0-2 throughout the 15 years of decreasing atmospheric sulfate concentrations, and little change in particle ammonium nitrate concentrations. We conclude that the reductions in aerosol acidity widely anticipated from sulfur reductions, and expected acidity-related health and climate benefits, are unlikely to occur until atmospheric sulfate concentrations reach near pre-anthropogenic levels.

  14. Airway responses to sulfate and sulfuric acid aerosols in asthmatics. An exposure-response relationship. (United States)

    Utell, M J; Morrow, P E; Speers, D M; Darling, J; Hyde, R W


    Epidemiologic studies support an association between elevated levels of sulfates and increased symptoms in asthmatics. To determine if these pollutants produce airway responses, 17 asthmatics inhaled the following sulfates: sodium bisulfate, ammonium sulfate, ammonium bisulfate (NH4HSO4), or sulfuric acid (H2SO4) aerosols with an aerodynamic diameter of 0.80 micron at concentrations of 100 micrograms/m3, 450 micrograms/m3, and 1,000 micrograms/m3. A sodium chloride (NaCl) aerosol of similar characteristics, administered by double-blind randomization, served as a control. Subjects breathed these aerosols for a 16-minute period via a mouthpiece. Deposition studies showed 54 to 65% retention of the inhaled aerosols. At the 1,000 micrograms/m3 concentration, the Threshold Limit Value for occupational exposure, H2SO4 and NH4HSO4 inhalation produced significant reductions in specific airway conductance (SGaw) (p less than 0.05) and forced expiratory volume in one second (p less than 0.01) compared with NaCl or pre-exposure values. At the 450 micrograms/m3 concentration, only H2SO4 inhalation produced a significant reduction in SGaw (p less than 0.01). At 100 micrograms/m3, a level 3 to 5 times greater than peak urban levels, no significant change in airway function occurred after any sulfate exposure. These data indicate that asthmatics demonstrate bronchoconstriction after brief exposure to common acidic sulfate pollutants.

  15. 77 FR 65532 - Solid Fertilizer Grade Ammonium Nitrate From the Russian Federation: Notice of Rescission of... (United States)


    ... International Trade Administration Solid Fertilizer Grade Ammonium Nitrate From the Russian Federation: Notice... the antidumping duty order on solid fertilizer grade ammonium nitrate (ammonium nitrate) from the... Administrative Review: Solid Fertilizer Grade Ammonium Nitrate (Ammonium Nitrate) from the Russian...

  16. Controlled exposures of human volunteers to sulfate aerosols. Health effects and aerosol characterization. (United States)

    Avol, E L; Jones, M P; Bailey, R M; Chang, N M; Kleinman, M T; Linn, W S; Bell, K A; Hackney, J D


    Our laboratory has undertaken the study of possible acute adverse health effects of sulfate aerosols through controlled exposures of volunteer human subjects. Both healthy and asthmatic adult men were exposed for 2-hour periods (with intermittent exercise) to ammonium sulfate, ammonium bisulfate, and sulfuric acid of particle size distributions and concentrations intended to simulate "worst case" exposures during Los Angeles smog episodes. Lung function tests were performed by the subjects on entering and before exiting from a carefully controlled environmental chamber. Subject symptoms were evluated in a standardized manner. Aerosol concentrations and size distributions were determined by an on-line computer/aerometric monitoring system; gravimetric and chemical analyses were performed on impactor and total filter samples after test exposures. We found little or no evidence of adverse health effects from 2-hour multiple-day exposures to any of the compounds at "worst case" ambient concentrations.

  17. Natural Nitrogen—15 Abundance of Ammonium Nitrogen and Fixed Ammonium in Soils

    Institute of Scientific and Technical Information of China (English)



    The present article deals with the natural nitrogen-15 abundance of ammonium nitrogen and fixed ammonium in different soils.Variations in the natural 15N abundance of ammonium nitrogen mineralized in soils under anaerobic incubation condition were related to soil pH.The δ 15N of mineralizable N in acid soils was lower but that in neutral and calcareous soils was higher compared with the δ 15N of total N in the soils.A variation tendence was also found in the δ 15N of amino-acid N in the hydrolysates of soils.The natural 15N abundance of fixed ammonium was higher than that of total N in most surface soils and other soil horizons,indicating that the increase of δ 15N in the soil borizons beneath subsurface horizon of some forest soils and acid paddy soils was related to the higher δ 15N value of fixed ammonium in the soil.

  18. Calcium sulphate in ammonium sulphate solution (United States)

    Sullivan, E.C.


    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.

  19. Preparation and Catalytic Properties of Iron-Cerium Phosphates with Sodium Dodecyl Sulfate


    Hiroaki Onoda; Takeshi Sakumura


    Iron phosphate was prepared from iron nitrate and phosphoric acid with sodium dodecyl sulfate at various stirring hours. The chemical composition of the obtained samples was estimated from ICP and XRD measurements. Particle shape and size distribution were observed by SEM images and laser diffraction/scattering methods. Further, the catalytic activity was studied with the decomposition of the complex between formaldehyde, ammonium acetate, and acetylacetone. The peaks of FePO4 were observed i...

  20. Reduction in Ammonium Ions in Sludge Liquor

    Directory of Open Access Journals (Sweden)

    Eglė Šlajūtė


    Full Text Available Liquor rejected from the centrifugation of the digested sludge can contain the concentrations of ammonium ions up to 1750 mg/L. These loads are usually returned to the intake of wastewater treatment plants (WWTP without additional treatment and can have a negative impact on biological wastewater and/or sludge treatment processes, e.g. phosphorus and nitrogen removal. This article deals with the use of naturally obtained sorbent, zeolite, in batch and column test procedure for removing ammonium from the rejected liquor. This research study was carried out using different sizes of zeolite particles: 0.8–1.6 mm and 1.6–2.5 mm. The highest efficiency of ammonium removal (up to 98 % was achieved by applying the zeolite particles of 0.8–1.6 mm.Article in Lithuanian

  1. Mineral carbonation of phosphogypsum waste for production of useful carbonate and sulfate salts

    Directory of Open Access Journals (Sweden)

    Hannu-Petteri eMattila


    Full Text Available Phosphogypsum (CaSO4·2H2O waste is produced in large amounts during phosphoric acid (H3PO4 production. Minor quantities are utilized in construction or agriculture, while most of the material is stockpiled, creating an environmental challenge to prevent pollution of natural waters. In principle, the gypsum waste could be used to capture several hundred Mt of carbon dioxide (CO2. For example, when gypsum is converted to ammonium sulfate ((NH42SO4 with ammonia (NH3 and CO2, also solid calcium carbonate (CaCO3 is generated. The ammonium sulfate can be utilized as a fertilizer or in other mineral carbonation processes that use magnesium silicate-based rock as feedstock, while calcium carbonate has various uses as e.g. filler material. The reaction extent of the described process was studied by thermodynamic modeling and experimentally as a function of reactant concentrations and temperature. Other essential properties such as purity and quality of the solid products are also followed. Conversion efficiencies of >95% calcium from phosphogypsum to calcium carbonate are obtained. Scalenohedral, rhombohedral and prismatic calcite particles can be produced, though the precipitates contain certain contaminants such as rare earth metals and sulfur from the gypsum. A reverse osmosis membrane cartridge is also tested as an alternative and energy-efficient method of concentrating the ammonium sulfate salt solution instead of the traditional evaporation of the process solution.

  2. Synthesis of ammonium and sulfate ion-functionalized titanium dioxide for photocatalytic applications (United States)

    Cheng, J. L.; Mi, J. Y.; Miao, H.; Sharifah Fatanah, B. S. A.; Wong, S. F.; Tay, B. K.


    Due to high band gap energy the optimum photocatalytic activities can only be achieved under UV light, thus limiting the practical application of TiO2. In this study, a method combining NH4 +/SO4 2--functionalization technique and post-treatment was developed and successfully applied to synthesize photoactive TiO2 samples which showed higher photocatalytic activity than the commercial P25 TiO2 under visible light radiation. The results also showed that the addition of (NH4)2SO4 surface functionalization on TiO2 increased the photocatalytic activity, which could be due to the combined effect of crystallinity and band gap energies. Moreover, the results showed that calcination temperature was inversely proportional to photocatalytic activity. The degradation efficiency for methylene blue under visible light was improved by 2 times from 10.7% for P25 nano Degussa TiO2 to 20.2% for the synthesized sample. The band gap energies were also reduced from 3.7 to 3.4 eV (under UV-Vis direct transition mode) indicating a red shift towards higher wavelength.

  3. Thermodynamics and kinetics of extracting zinc from zinc oxide ore by the ammonium sulfate roasting method (United States)

    Sun, Yi; Shen, Xiao-yi; Zhai, Yu-chun


    Thermodynamic analyses and kinetic studies were performed on zinc oxide ore treatment by (NH4)2SO4 roasting technology. The results show that it is theoretically feasible to realize a roasting reaction between the zinc oxide ore and (NH4)2SO4 in a temperature range of 573-723 K. The effects of reaction temperature and particle size on the extraction rate of zinc were also examined. It is found that a surface chemical reaction is the rate-controlling step in roasting kinetics. The calculated activation energy of this process is about 45.57 kJ/mol, and the kinetic model can be expressed as follows: 1 - (1 - α)1/3 = 30.85 exp(-45.57/ RT)· t. An extraction ratio of zinc as high as 92% could be achieved under the optimum conditions.

  4. The modulation of cell surface cAMP receptors from Dictyostelium disscoideum by ammonium sulfate

    NARCIS (Netherlands)

    Haastert, Peter J.M. van


    Dictyostelium discoideum cells contain a heterogeneous population of cell surface cAMP receptors with components possessing different affinities (Kd between 15 and 450 nM) and different off-rates of the cAMP-receptor complex (t½ between 0.7 and 150 s). The association of cAMP to the receptor and the

  5. Interaction of PACls with sulfate

    Institute of Scientific and Technical Information of China (English)

    XU Yi; WANG Dong-Sheng; TANG Hong-Xiao


    This article discusses the influential factors on Al13 separation considering the interaction of sulfate with various polyaluminum chloride(PACl). The experimental results showed that the basicity(B=[OH]/[Al]), the concentration of PACl and Al/SO4 ratio exhibited significant roles in the PACl-sulfate reaction. It indicated that different species in various PACl underwent different reaction pathway with sulfate. The Alc, colloidal species, formed precipitation quickly with sulfate, while Alb, oligomers and polymers, undergoes slow crystallization. And Ala, monomers, reacts with sulfate to form soluble complexes. The kinetic difference of reaction made it possible to realize the separation of Alb and further purification. The decrease of Ala resulted in the limit of ferron method was also mentioned.

  6. Final report on the safety assessment of sodium sulfite, potassium sulfite, ammonium sulfite, sodium bisulfite, ammonium bisulfite, sodium metabisulfite and potassium metabisulfite. (United States)

    Nair, Bindu; Elmore, Amy R


    Sodium Sulfite, Ammonium Sulfite, Sodium Bisulfite, Potassium Bisulfite, Ammonium Bisulfite, Sodium Metabisulfite, and Potassium Metabisulfite are inorganic salts that function as reducing agents in cosmetic formulations. All except Sodium Metabisulfite also function as hair-waving/straightening agents. In addition, Sodium Sulfite, Potassium Sulfite, Sodium Bisulfite, and Sodium Metabisulfite function as antioxidants. Although Ammonium Sulfite is not in current use, the others are widely used in hair care products. Sulfites that enter mammals via ingestion, inhalation, or injection are metabolized by sulfite oxidase to sulfate. In oral-dose animal toxicity studies, hyperplastic changes in the gastric mucosa were the most common findings at high doses. Ammonium Sulfite aerosol had an acute LC(50) of >400 mg/m(3) in guinea pigs. A single exposure to low concentrations of a Sodium Sulfite fine aerosol produced dose-related changes in the lung capacity parameters of guinea pigs. A 3-day exposure of rats to a Sodium Sulfite fine aerosol produced mild pulmonary edema and irritation of the tracheal epithelium. Severe epithelial changes were observed in dogs exposed for 290 days to 1 mg/m(3) of a Sodium Metabisulfite fine aerosol. These fine aerosols contained fine respirable particle sizes that are not found in cosmetic aerosols or pump sprays. None of the cosmetic product types, however, in which these ingredients are used are aerosolized. Sodium Bisulfite (tested at 38%) and Sodium Metabisulfite (undiluted) were not irritants to rabbits following occlusive exposures. Sodium Metabisulfite (tested at 50%) was irritating to guinea pigs following repeated exposure. In rats, Sodium Sulfite heptahydrate at large doses (up to 3.3 g/kg) produced fetal toxicity but not teratogenicity. Sodium Bisulfite, Sodium Metabisulfite, and Potassium Metabisulfite were not teratogenic for mice, rats, hamsters, or rabbits at doses up to 160 mg/kg. Generally, Sodium Sulfite, Sodium

  7. The measurement of H 2SO 4 and other sulfate species at Tuxedo, New York with a thermal analysis flame photometric detector and simultaneously collected quartz filter samples (United States)

    Morandi, Maria T.; Kneip, Theo J.; Geoffery Cobourn, W.; Husar, Rudolf B.; Lioy, Paul J.

    A study of major atmospheric particulate sulfate species was conducted during 30 July 1980-1983 September 1980 in Sterling Forest, a rural area in Tuxedo, NY, not affected by major local sources of pollution. In situ measurements of total sulfate, sulfuric acid and ammonium sulfate ammonium bisulfate were made using Thermal Analysis-Flame Photometric Detection (TA-FPD). These measurements were compared to the total sulfate and strong acid (H +) concentration measured in simultaneously collected 12 h, treated quartz filter samples. The concentration of NH 4HSO 4 was inferred from the difference between the total strong acid concentration and the sulfuric acid measurements, so that total sulfate and acid concentrations could be balanced. A major sulfate pollution episode occurred during the period of 27-29 August. The concentration of H + showed an excess above that necessary to account for the TA-FPD H 2SO 4 measurement, indicating the presence of NH 4 HSO 4. The maximum 12 h average concentrations of H 2SO 4, NH 4HSO 4 and (NH 4) 2SO 4 were 5.18, 11.42 and 10.08 μg m -3 as SO 42- respectively, and were measured from 9:15 to 21:15 on 28 August. The study demonstrated the usefulness of concurrent measurements of airborne particulate sulfate by filter extraction and TA-FPD to identify acidic sulfate species.

  8. Effects of Aromatic Ammoniums on Methyl Ammonium Lead Iodide Hybrid Perovskite Materials

    Directory of Open Access Journals (Sweden)

    Jianli Yang


    Full Text Available The introduction of bulky ammoniums into methyl ammonium lead iodide hybrid perovskites (MAPbI3 has emerged as a promising strategy to improve the properties of these materials. In the present work, we studied the effects of several aromatic ammoniums onto the structural, electronic, and optical properties of MAPbI3. Although powder XRD data suggest that the bulky cations are not involved in the bulk phase of the MAPbI3, a surprisingly large effect of the bulky cations onto the photoluminescence properties was observed.

  9. Review of Ammonium Dinitramide Toxicity Studies (United States)


    reproductive toxicant in rats, causing implantation failure in early gestation; follow-on studies implied that ADN is embryotoxic . EPR studies indicated that...mutagenic. 15. SUBJECT TERMS Ammonium dinitramide, ADN, toxicity, reproductive, embryotoxic , genotoxicity 16. SECURITY CLASSIFICATION OF: U 17...reproductive studies, reproduction and fertility, pre-implantation and post-implantation studies, implied that ADN is embryotoxic . A mouse embryo

  10. Detonation characteristics of ammonium nitrate products

    NARCIS (Netherlands)

    Kersten, R.J.A.; Hengel, E.I.V. van den; Steen, A.C. van der


    The detonation properties of ammonium nitrate (AN) products depend on many factors and are therefore, despite the large amount of information on this topic, difficult to assess. In order to further improve the understanding of the safety properties of AN, the European Fertilizer Manufacturers Associ

  11. Topaz concentrate desiliconization with ammonium bifluoride


    Andreev, V. A.; Buynovskiy, A. S.; Andreev, Artyom Andreevich; Dyachenko, Alexander Nikolaevich


    Fluoridizing agent for the process of topaz concentrate desiliconization has been selected, topaz thermodynamic potentials have been appraised, thermodynamic probabilities of fluorination reaction of topaz concentrate main constituents have been calculated. The results of studying the concentrate desiliconization process with ammonium bifluoride by the methods of thermogravimetry, RFA, microphotography are presented

  12. Comparative irritant potency of inhaled sulfate aerosols--effects on bronchial mucociliary clearance. (United States)

    Schlesinger, R B


    The effect of 1-hr oral inhalation exposures to submicrometer aerosols of ammonium bisulfate (NH4HSO4), ammonium sulfate [NH4)2SO4), and sodium sulfate (Na2SO4) upon mucociliary clearance from the bronchial tree of rabbits was examined. Exposures to NH4HSO4 at concentrations of approximately 600-1700 micrograms/m3 produced a significant depression of clearance rate only at the highest exposure level. No significant effects were observed with the other sulfates at levels up to approximately 2000 micrograms/m3. When results were compared to those from another study in this laboratory using sulfuric acid (H2SO4) aerosol, the ranking of irritant potency was H2SO4 greater than NH4HSO4 greater than (NH4)2SO4, Na2SO4. Alteration in bronchial mucociliary clearance due to sulfate aerosols appears to be related to the deposition of [H+] on the mucus lining of conducting airways.

  13. Ice Formation by Sulfate and Sulfuric Acid Aerosol Particles under Upper-Tropospheric Conditions. (United States)

    Chen, Yalei; Demott, Paul J.; Kreidenweis, Sonia M.; Rogers, David C.; Eli Sherman, D.


    Ice formation in ammoniated sulfate and sulfuric acid aerosol particles under upper-tropospheric conditions was studied using a continuous flow thermal diffusion chamber. This technique allowed for particle exposure to controlled temperatures and relative humidities for known residence times. The phase states of (NH4)2SO4 and NH4HSO4 particles were found to have important impacts on their ice formation capabilities. Dry (NH4)2SO4 particles nucleated ice only at high relative humidity (RH 94%) with respect to water at temperatures between 40° and 60°C. This result suggested either an impedance or finite time dependence to deliquescence and subsequent homogeneous freezing nucleation. Ammonium sulfate particles that entered the diffusion chamber in a liquid state froze homogeneously at relative humidities that were 10% lower than where ice nucleated on initially dry particles. Likewise, crystalline or partially crystallized (as letovicite) NH4HSO4 particles required higher relative humidities for ice nucleation than did initially liquid bisulfate particles. Liquid particles of size 0.2 m composed of either ammonium sulfate or bisulfate froze at lower relative humidity at upper-tropospheric temperatures than did 0.05-m sulfuric acid aerosol particles. Comparison of calculated homogeneous freezing point depressions suggest that size effects on freezing may be more important than the degree of ammoniation of the sulfate compound.

  14. Effective Henry's law partitioning and the salting constant of glyoxal in aerosols containing sulfate. (United States)

    Kampf, Christopher J; Waxman, Eleanor M; Slowik, Jay G; Dommen, Josef; Pfaffenberger, Lisa; Praplan, Arnaud P; Prévôt, André S H; Baltensperger, Urs; Hoffmann, Thorsten; Volkamer, Rainer


    The reversible partitioning of glyoxal was studied in simulation chamber experiments for the first time by time-resolved measurements of gas-phase and particle-phase concentrations in sulfate-containing aerosols. Two complementary methods for the measurement of glyoxal particle-phase concentrations are compared: (1) an offline method utilizing filter sampling of chamber aerosols followed by HPLC-MS/MS analysis and (2) positive matrix factorization (PMF) analysis of aerosol mass spectrometer (AMS) data. Ammonium sulfate (AS) and internally mixed ammonium sulfate/fulvic acid (AS/FA) seed aerosols both show an exponential increase of effective Henry's law coefficients (KH,eff) with AS concentration (cAS, in mol kg(-1) aerosol liquid water, m = molality) and sulfate ionic strength, I(SO4(2-)) (m). A modified Setschenow plot confirmed that "salting-in" of glyoxal is responsible for the increased partitioning. The salting constant for glyoxal in AS is K(S)CHOCHO = (-0.24 ± 0.02) m(-1), and found to be independent of the presence of FA. The reversible glyoxal uptake can be described by two distinct reservoirs for monomers and higher molecular weight species filling up at characteristic time constants. These time constants are τ1 ≈ 10(2) s and τ2 ≈ 10(4) s at cAS < 12 m, and about 1-2 orders of magnitude slower at higher cAS, suggesting that glyoxal uptake is kinetically limited at high salt concentrations.

  15. Sulfate transport in toad skin

    DEFF Research Database (Denmark)

    Larsen, Erik Hviid; Simonsen, K


    1. In short-circuited toad skin preparations exposed bilaterally to NaCl-Ringer's containing 1 mM SO2(-4), influx of sulfate was larger than efflux showing that the skin is capable of transporting sulfate actively in an inward direction. 2. This active transport was not abolished by substituting...... apical Na+ for K+. 3. Following voltage activation of the passive Cl- permeability of the mitochondria-rich (m.r.) cells sulfate flux-ratio increased to a value predicted from the Ussing flux-ratio equation for a monovalent anion. 4. In such skins, which were shown to exhibit vanishingly small leakage...

  16. Surface investigation and tribological mechanism of a sulfate-based lubricant deposited on zinc-coated steel sheets (United States)

    Timma, Christian; Lostak, Thomas; Janssen, Stella; Flock, Jörg; Mayer, Christian


    Phosphatation is a well-known technique to improve friction and wear behaviour of zinc coated steel, but has a variety of economic and ecologic limitations. In this study an alternative coating based on ammonium sulfate ((NH4)2SO4) is applied on skin-passed hot-dip galvanized steel sheets in order to investigate its surface chemical and tribological behaviour in a Pin-on-Disk Tribometer. Raman- and X-ray photoelectron spectroscopic results revealed a formation of ammonium zinc sulfate ((NH4)2Zn(SO4)2 * xH2O) on the surface, which is primarily located in the skin-passed areas of the steel material. Sulfate coated samples exhibited a superior friction behaviour in Pin-on-Disk Tests using squalane as a model substance for oil-like lubricated conditions and a formation of a thin lubrication film is obtained in the wear track. Squalane acts as a carrier substance for ammonium zinc sulfate, leading to an effective lubrication film in the wear track.

  17. p-Cresyl Sulfate

    Directory of Open Access Journals (Sweden)

    Tessa Gryp


    Full Text Available If chronic kidney disease (CKD is associated with an impairment of kidney function, several uremic solutes are retained. Some of these exert toxic effects, which are called uremic toxins. p-Cresyl sulfate (pCS is a prototype protein-bound uremic toxin to which many biological and biochemical (toxic effects have been attributed. In addition, increased levels of pCS have been associated with worsening outcomes in CKD patients. pCS finds its origin in the intestine where gut bacteria metabolize aromatic amino acids, such as tyrosine and phenylalanine, leading to phenolic end products, of which pCS is one of the components. In this review we summarize the biological effects of pCS and its metabolic origin in the intestine. It appears that, according to in vitro studies, the intestinal bacteria generating phenolic compounds mainly belong to the families Bacteroidaceae, Bifidobacteriaceae, Clostridiaceae, Enterobacteriaceae, Enterococcaceae, Eubacteriaceae, Fusobacteriaceae, Lachnospiraceae, Lactobacillaceae, Porphyromonadaceae, Staphylococcaceae, Ruminococcaceae, and Veillonellaceae. Since pCS remains difficult to remove by dialysis, the gut microbiota could be a future target to decrease pCS levels and its toxicity, even at earlier stages of CKD, aiming at slowing down the progression of the disease and decreasing the cardiovascular burden.

  18. p-Cresyl Sulfate (United States)

    Gryp, Tessa; Vanholder, Raymond; Vaneechoutte, Mario; Glorieux, Griet


    If chronic kidney disease (CKD) is associated with an impairment of kidney function, several uremic solutes are retained. Some of these exert toxic effects, which are called uremic toxins. p-Cresyl sulfate (pCS) is a prototype protein-bound uremic toxin to which many biological and biochemical (toxic) effects have been attributed. In addition, increased levels of pCS have been associated with worsening outcomes in CKD patients. pCS finds its origin in the intestine where gut bacteria metabolize aromatic amino acids, such as tyrosine and phenylalanine, leading to phenolic end products, of which pCS is one of the components. In this review we summarize the biological effects of pCS and its metabolic origin in the intestine. It appears that, according to in vitro studies, the intestinal bacteria generating phenolic compounds mainly belong to the families Bacteroidaceae, Bifidobacteriaceae, Clostridiaceae, Enterobacteriaceae, Enterococcaceae, Eubacteriaceae, Fusobacteriaceae, Lachnospiraceae, Lactobacillaceae, Porphyromonadaceae, Staphylococcaceae, Ruminococcaceae, and Veillonellaceae. Since pCS remains difficult to remove by dialysis, the gut microbiota could be a future target to decrease pCS levels and its toxicity, even at earlier stages of CKD, aiming at slowing down the progression of the disease and decreasing the cardiovascular burden. PMID:28146081

  19. Determination of homologues of quaternary ammonium surfactants by capillary electrophoresis using indirect UV detection. (United States)

    Liu, Hsueh-Ying; Ding, Wang-Hsien


    This investigation describes the simultaneous separation of two major non-chromophoric quaternary ammonium surfactants, alkyltrimethyl- and dialkyldimethylammonium compounds (ATMACs and DADMACs, respectively), by capillary electrophoresis (CE) using indirect UV detection. The most effective separation conditions was 10 mM phosphate buffer with 57.5% tetrahydrofuran and 3 mM sodium dodecyl sulfate (SDS) at pH 4.3, and the sample hydrodynamic injection of up to 20 s at 1 psi (approximately 60 nl), and an applied voltage of 25 kV (1 psi = 6.9 kPa). Specially, the selection of an appropriate chromophore and an internal standard (I.S.) to improve the peak identification and quantitation was systematically investigated. Decylbenzyldimethyl ammonium chloride (C10-BDMA+C-) as a chromophore with 3 mM sodium dodecyl sulfate provided the best detectability for all homologues. The reproducibility of the migration time and quantitative analysis can be improved by using tetraoctyl ammonium ion as an internal standard, giving the relative standard deviation (R.S.D.) less than 0.8% for the relative migration times, and 2.5-5.5% for the relative peak areas. A good linearity of CE analysis was obtained in the range of 1.0-20 microg/ml with r2 values of above 0.999. The analysis of cationic surfactants in commercial products of hair conditioners and fabric softeners was also performed. Electrospray mass spectrometric method was applied to evaluate the CE method, and the compatible results were obtained.

  20. Development and validation of stability-indicating HPLC method for determination of cefpirome sulfate. (United States)

    Zalewski, Przemysław; Skibiński, Robert; Cielecka-Piontek, Judyta; Bednarek-Rajewska, Katarzyna


    The stability-indicating LC assay method was developed and validated for quantitative determination of cefpirome sulfate (CPS) in the presence of degradation products formed during the forced degradation studies. An isocratic HPLC method was developed with Lichrospher RP-18 column, 5 μm particle size, 125 mm x 4 mm column and 12 mM ammonium acetate-acetonitrile (90 : 10 v/v) as a mobile phase. The flow rate of the mobile phase was 1.0 mL/min. Detection wavelength was 270 nm and temperature was 30 degrees C. Cefpirome sulfate as other cephalosporins was subjected to stress conditions of degradation in aqueous solutions including hydrolysis, oxidation, photolysis and thermal degradation. The developed method was validated with regard to linearity, accuracy, precision, selectivity and robustness. The method was applied successfully for identification and determination of cefpirome sulfate in pharmaceuticals and during kinetic studies.

  1. Integrated approach for investigating the durability of self-consolidating concrete to sulfate attack (United States)

    Bassuoni, Mohamed Tamer F.

    The growing use of self-consolidating concrete (SCC) in various infrastructure applications exposed to sulfate-rich environments necessitates conducting comprehensive research to evaluate its durability to external sulfate attack. Since the reliability and adequacy of standard sulfate immersion tests have been questioned, the current thesis introduced an integrated testing approach for assessing the durability of a wide scope of SCC mixtures to external sulfate attack. This testing approach involved progressive levels of complexity from single to multiple damage processes. A new series of sulfate attack tests involving multiple field-like parameters and combined damage mechanisms (various cations, controlled pH, wetting-drying, partial immersion, freezing-thawing, and cyclic cold-hot conditions with or without sustained flexural loading) were designed to evaluate the performance (suitability) of the SCC mixtures under various sulfate attack exposure scenarios. The main mixture design variables of SCC included the type of binder (single, binary, ternary and quaternary), air-entrainment, sand-to-aggregate mass ratio and hybrid fibre reinforcement. The comprehensive database and knowledge obtained from this research were used to develop smart models (fuzzy and neuro-fuzzy inference systems) based on artificial-intelligence to evaluate and predict the performance of the SCC mixtures under various sulfate attack exposure regimes implemented in this study. In full immersion tests involving high concentration sodium and magnesium sulfate solutions with controlled pH, the low penetrability of SCC was responsible for the high durability of specimens. Ternary and quaternary cementitious systems with or without limestone materials provided a passivating layer, with or without acid neutralization capacity, which protected SCC from severe damage in the aggressive sulfuric acid and ammonium sulfate solutions. In contrast to conclusions drawn from the sodium sulfate immersion

  2. Analysis of an explosion accident of nitrogen trichloride in a waste liquid containing ammonium ion and platinum black. (United States)

    Okada, Ken; Akiyoshi, Miyako; Ishizaki, Keiko; Sato, Hiroyasu; Matsunaga, Takehiro


    Five liters of sodium hypochlorite aqueous solution (12 mass%) was poured into 300 L of liquid waste containing ammonium ion of about 1.8 mol/L in a 500 L tank in a plant area; then, two minutes later the solution exploded with a flash on March 30th, 2005. The tank cover, the fluorescent lamp and the air duct were broken by the blast wave. Thus, we have conducted 40 runs of laboratory-scale explosion tests under various conditions (solution concentrations of (NH4)2SO4 and NaClO, temperatures, Pt catalysts, pH, etc.) to investigate the causes for such an explosion. When solutions of ammonium sulfate and sodium hypochlorite are mixed in the presence of platinum black, explosions result. This is ascribable to the formation of explosive nitrogen trichloride (NCl3). In the case where it is necessary to mix these 2 solutions (ammonium sulfate and sodium hypochlorite) in the presence of platinum black, the following conditions would reduce a probability of explosion; the initial concentration of NH4(+) should be less than 3 mol/L and the pH should be higher than 6. The hypochlorite solution (in 1/10 in volume) to be added at room temperature is recommended to be less than 0.6 mol/L.

  3. 21 CFR 184.1141b - Ammonium phosphate, dibasic. (United States)


    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ammonium phosphate, dibasic. 184.1141b Section 184... Listing of Specific Substances Affirmed as GRAS § 184.1141b Ammonium phosphate, dibasic. (a) Ammonium phosphate, dibasic ((NH4)2HPO4, CAS Reg. No. 7783-28-0) is manufactured by reacting ammonia with...

  4. 21 CFR 172.165 - Quaternary ammonium chloride combination. (United States)


    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Quaternary ammonium chloride combination. 172.165... HUMAN CONSUMPTION Food Preservatives § 172.165 Quaternary ammonium chloride combination. The food additive, quaternary ammonium chloride combination, may be safely used in food in accordance with...

  5. 78 FR 32690 - Certain Ammonium Nitrate From Ukraine (United States)


    ... COMMISSION Certain Ammonium Nitrate From Ukraine Determination On the basis of the record \\1\\ developed in... antidumping duty order on certain ammonium nitrate from Ukraine would be likely to lead to continuation or... Publication 4396 (May 2013), entitled Certain Ammonium Nitrate from Ukraine: Investigation No....

  6. 21 CFR 184.1296 - Ferric ammonium citrate. (United States)


    ... citrate (iron (III) ammonium citrate) is prepared by the reaction of ferric hydroxide with citric acid, followed by treatment with ammonium hydroxide, evaporating, and drying. The resulting product occurs in two forms depending on the stoichiometry of the initial reactants. (1) Ferric ammonium citrate (iron...

  7. 21 CFR 558.364 - Neomycin sulfate. (United States)


    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Neomycin sulfate. 558.364 Section 558.364 Food and... in Animal Feeds § 558.364 Neomycin sulfate. (a) Approvals. Type A medicated article: 325 grams per.... (c) (d) Conditions of use. Neomycin sulfate is used as follows: Neomycin Sulfate...

  8. 21 CFR 184.1307 - Ferric sulfate. (United States)


    ... Substances Affirmed as GRAS § 184.1307 Ferric sulfate. (a) Ferric sulfate (iron (III) sulfate, Fe2(SO4)3 CAS Reg. No. 10028-22-5) is a yellow substance that may be prepared by oxidizing iron (II) sulfate or by treating ferric oxide or ferric hydroxide with sulfuric acid. (b) The ingredient must be of a...

  9. Quaternary ammonium compounds – New occupational hazards

    Directory of Open Access Journals (Sweden)

    Agnieszka Lipińska-Ojrzanowska


    Full Text Available Quaternary ammonium compounds (QACs, quats belong to organic ionic chemical agents which display unique properties of both surfactants and disinfectants. Their wide distribution in the work environment and also in private households brings about new occupational hazards. This paper reviews reports about the health effects of QACs. QACs could play a role of sensitizers and irritants to the skin and mucous membranes. It is suspected that particular QACs can display an immunologic crossreactivity between each other and with other chemical compounds containing ammonium ion, such as muscle relaxants widely used in anesthesia. They may promote the development of airway allergy, however, the background mechanisms are still unclear and need to be further investigated. Until now, a few cases of occupational asthma induced by QACs have been described and their involvement in contact dermatitis has been documented. The possibility of anaphylaxis due to QACs cannot be excluded as well. Med Pr 2014;65(5:675–682

  10. Detonation Properties of Ammonium Dinitramide (ADN) (United States)

    Wätterstam, A.; Östmark, H.; Helte, A.; Karlsson, S.


    Ammonium Dinitramide, ADN, has a potential as an oxidizer for underwater high explosives. Pure ADN has a large reaction-zone length and shows a strong non-ideal behaviour. The work presented here is an extension of previous work.(Sensitivity and Performance Characterization of Ammonium Dinitramide (ADN). Presented at 11th International Detonation Symposium, Snowmass, CO, 1998.) Experiments for determining the detonation velocity as a function of inverse charge radius and density, reaction-zone length and curvature, and the detonation pressure are presented. Measurements of pressure indicates that no, or weak von-Neumann spike exists, suggesting an immediate chemical decomposition. Experimental data are compared with predicted using thermochemical codes and ZND-theory.

  11. The Pacific Marine aerosol: Evidence for natural acid sulfates (United States)

    Clarke, Antony D.; Ahlquist, Norman C.; Covert, David S.


    Optical, chemical, and physical measurements of marine boundary layer aerosol were made during two oceanographic cruises in the central Pacific in the fall of 1983 and spring of 1984. Both cruises revealed a ubiquitous accumulation mode atmospheric aerosol that showed marked increases in the region of equatorial upwelling, 4°N to 15°S, between Hawaii and Tahiti. Changes in the aerosol size distribution in response to thermal conditioning revealed properties consistent with those of sulfuric acid and/or ammonium sulfate/bisulfate depending upon the sampling location. Changes in the apparent acidity of the accumulation mode varied in conjunction with physical and chemical properties of the region sampled, while the number concentration suggests that it is the dominant and possibly limiting aerosol for cloud condensation nuclei in the remote central Pacific.

  12. 转化法制备氯化铵的条件优化%Optimization of Conditions for Preparation of Ammonium Chloride Based Transformation Method

    Institute of Scientific and Technical Information of China (English)

    周德望; 郭必豹; 李祖略; 李芳


    以氯化钠和硫酸铵为原料,采用正交设计法对氯化铵的制备条件进行了优化。实验结果表明:在物料比为21,冰浴冷却时间为20 min,蒸发水量为45%,冷却温度为35℃的条件下,单次结晶氯化铵的产率和纯度明显提高。%An experimental program was designed for preparing ammonium chloride from sodium chloride and ammonium sulfate based on the orthogonal design. The optimum conditions were determined as follows: material ratio 2:1, cooling time 20 min and temperature 35 ℃,water evaporation 45%. Under above conditions, the productivity and pure of ammonium chloride could be improved dramatically.

  13. Heparan sulfate structure: methods to study N-sulfation and NDST action. (United States)

    Dagälv, Anders; Lundequist, Anders; Filipek-Górniok, Beata; Dierker, Tabea; Eriksson, Inger; Kjellén, Lena


    Heparan sulfate proteoglycans are important modulators of cellular processes where the negatively charged polysaccharide chains interact with target proteins. The sulfation pattern of the heparan sulfate chains will determine the proteins that will bind and the affinity of the interactions. The N-deacetylase/N-sulfotransferase (NDST) enzymes are of key importance during heparan sulfate biosynthesis when the sulfation pattern is determined. In this chapter, metabolic labeling of heparan sulfate with [(35)S]sulfate or [(3)H]glucosamine in cell cultures is described, in addition to characterization of polysaccharide chain length and degree of N-sulfation. Methods to measure NDST enzyme activity are also presented.

  14. Sulfate reduction in freshwater peatlands

    Energy Technology Data Exchange (ETDEWEB)

    Oequist, M.


    This text consist of two parts: Part A is a literature review on microbial sulfate reduction with emphasis on freshwater peatlands, and part B presents the results from a study of the relative importance of sulfate reduction and methane formation for the anaerobic decomposition in a boreal peatland. The relative importance of sulfate reduction and methane production for the anaerobic decomposition was studied in a small raised bog situated in the boreal zone of southern Sweden. Depth distribution of sulfate reduction- and methane production rates were measured in peat sampled from three sites (A, B, and C) forming an minerotrophic-ombrotrophic gradient. SO{sub 4}{sup 2-} concentrations in the three profiles were of equal magnitude and ranged from 50 to 150 {mu}M. In contrast, rates of sulfate reduction were vastly different: Maximum rates in the three profiles were obtained at a depth of ca. 20 cm below the water table. In A it was 8 {mu}M h{sup -1} while in B and C they were 1 and 0.05 {mu}M h{sup -1}, respectively. Methane production rates, however, were more uniform across the three nutrient regimes. Maximum rates in A (ca. 1.5 {mu}g d{sup -1} g{sup -1}) were found 10 cm below the water table, in B (ca. 1.0 {mu}g d{sup -1} g{sup -1}) in the vicinity of the water table, and in C (0.75 {mu}g d{sup -1} g{sup -1}) 20 cm below the water table. In all profiles both sulfate reduction and methane production rates were negligible above the water table. The areal estimates of methane production for the profiles were 22.4, 9.0 and 6.4 mmol m{sup -2} d{sup -1}, while the estimates for sulfate reduction were 26.4, 2.5, and 0.1 mmol m{sup -2} d{sup -1}, respectively. The calculated turnover times at the sites were 1.2, 14.2, and 198.7 days, respectively. The study shows that sulfate reducing bacteria are important for the anaerobic degradation in the studied peatland, especially in the minerotrophic sites, while methanogenic bacteria dominate in ombrotrophic sites Examination

  15. An aqueous chemistry module for a three-dimensional cloud resolving model: Sulfate redistribution

    Directory of Open Access Journals (Sweden)

    Vujović Dragana


    Full Text Available An aqueous chemistry module is created and included into a complex 3D cloud-resolving mesoscale ARPS model to examine the characteristics of in-cloud sulfate. The complex orography of Serbia is included in the model. The chemical species included in the module are sulfur dioxide, sulfate ion, ammonium ion, hydrogen peroxide and ozone. Six water categories are considered: water vapor, cloud water, rain, cloud ice, snow and hail. Each chemical species in each microphysical category is represented by a differential equation of mass continuity. This paper gives a detailed description of the chemistry module and demonstrates the utility of an atmospheric model coupled with the chemistry module in forecasting the redistribution of chemical species in all water categories. The main mean microphysical and chemical conversion rates of sulfate averaged over a 2 h simulation period for a base run are for the oxidation of S(IV in rain water and cloud water, SO4 2− scavenging by Brownian diffusion in cloud droplets and cloud ice as well as the impact scavenging of SO4 2− by rain. The calculated values of sulfates in all water categories and the shape of sulfate profiles depend on radar reflectivity.

  16. Studies on Sulfation of Lycium barbarum Polysaccharides

    Institute of Scientific and Technical Information of China (English)

    YI,Jian-Ping; YAN,Hong; ZHONG,Ru-Gang


    @@ Polysaccharides can anti-virus, such as human immunodeficiency virus (HIV-1),[1] herpes simplex virus (HSV-1,HSV-2) and cytomegalovirus. Some of them are sulfates, e.g. dextran sulfate, heparin, sulfonation of chitosan and sulfated derivatives of Lentinan. Our results showed that sulfated derivatives of Lycium barbarum polysaccharides (LBP)have anti-HIV activity. Because the anti-HIV activity of LBP was deeply dependent on the molecular weight, the sulfation pattern and glycosidic branches besides degree of sulfation (DS), so we emphasized our work on the factors of DS.



    S. Putra; I A.M. Sukarini


    ABSTRACT In line with the regional government programs in sustaining the agricultural ? livestock farming system. An informative talk on enhancing performances and productivity of kacang goat was held at Penatih, Badung reegency on the 20th Dec. 2002. The aim of the community service is to fulfill the farmer?s knowledge and their technical skill in choosing and applying proportional feed stuff, especially using ammonium sulfate mineral as feed supplement on grass-legume based diet....

  18. Stable Ammonium Bisulfate Clusters in the Atmosphere (United States)

    Vehkamäki, Hanna; Napari, Ismo; Kulmala, Markku; Noppel, Madis


    Liquid drop model based equilibrium thermodynamics predicts that in the presence of even small ammonia concentrations practically all the atmospheric sulfuric acid molecules are bound to tiny, stable ammonium-bisulfate clusters. Hitherto sulfuric acid has been believed to form hydrates with water. Thermodynamic theory predicts correctly the hydrate formation observed experimentally. Results from ab initio computer simulations contradict the thermodynamic results and also the experimental findings for cluster formation in both sulfuric acid-water and ammonia-sulfuric acid-water mixtures.

  19. A sulfate conundrum: Dissolved sulfates of deep-saline brines and carbonate-associated sulfates (United States)

    Labotka, Dana M.; Panno, Samuel V.; Locke, Randall A.


    Sulfates in deeply circulating brines and carbonate-associated sulfates (CAS) within sedimentary units of the Cambrian strata in the Illinois Basin record a complex history. Dissolved sulfate within the Mt. Simon Sandstone brines exhibits average δ34SSO4 values of 35.4‰ and δ18OSO4 values of 14.6‰ and appears to be related to Cambrian seawater sulfate, either original seawater or sourced from evaporite deposits such as those in the Michigan Basin. Theoretical and empirical relationships based on stable oxygen isotope fractionation suggest that sulfate within the lower depths of the Mt. Simon brines has experienced a long period of isolation, possibly several tens of millions of years. Comparison with brines from other stratigraphic units shows the Mt. Simon brines are geochemically unique. Dissolved sulfate from brines within the Ironton-Galesville Sandstone averages 22.7‰ for δ34SSO4 values and 13.0‰ for δ18OSO4 values. The Ironton-Galesville brine has mixed with younger groundwater, possibly of Ordovician to Devonian age and younger. The Eau Claire Formation lies between the Mt. Simon and Ironton-Galesville Sandstones. The carbonate units of the Eau Claire and stratigraphically equivalent Bonneterre Formation contain CAS that appears isotopically related to the Late Pennsylvanian-Early Permian Mississippi Valley-type ore pulses that deposited large sulfide minerals in the Viburnum Trend/Old Lead Belt ore districts. The δ34SCAS values range from 21.3‰ to 9.3‰, and δ18OCAS values range from +1.4‰ to -2.6‰ and show a strong covariance (R2 = 0.94). The largely wholesale replacement of Cambrian seawater sulfate signatures in these dolomites does not appear to have affected the sulfate signatures in the Mt. Simon brines even though these sulfide deposits are found in the stratigraphically equivalent Lamotte Sandstone to the southwest. On the basis of this and previous studies, greater fluid densities of the Mt. Simon brines may have prevented the

  20. Sulfation of thyroid hormone by estrogen sulfotransferase

    NARCIS (Netherlands)

    M.H.A. Kester (Monique); T.J. Visser (Theo); C.H. van Dijk (Caren); D. Tibboel (Dick); A.M. Hood (Margaret); N.J. Rose; W. Meinl; U. Pabel; H. Glatt; C.N. Falany; M.W. Coughtrie


    textabstractSulfation is one of the pathways by which thyroid hormone is inactivated. Iodothyronine sulfate concentrations are very high in human fetal blood and amniotic fluid, suggesting important production of these conjugates in utero. Human estrogen sulfotransferas

  1. Purification of human immunoglobulins by sequential precipitation with caprylic acid and ammonium sulphate. (United States)

    Perosa, F; Carbone, R; Ferrone, S; Dammacco, F


    We have tested the usefulness of sequential precipitation with caprylic acid and ammonium sulfate to purify human monoclonal and polyclonal immunoglobulins from sera of 11 patients with monoclonal gammapathy (4 IgG kappa, 2 IgG lambda, 2 IgM kappa, 1 IgA kappa, 2 IgA lambda), four patients with autoimmune diseases and four healthy donors. In terms of purity and activity of Ig as well as execution time and cost, this two-step non-chromatographic procedure is highly efficient for the purification of IgG, IgA and IgM, thus offering several advantages over other methods of purification. Therefore, this procedure may have useful application in the preparation of human Ig for structural studies and therapeutic purposes.

  2. Synthesis of novel quaternary ammonium surfactants containing adamantane

    Institute of Scientific and Technical Information of China (English)

    Jian Wei Guo; Xing Zhong; Hua Zhu; Li Juan Feng; Ying De Cui


    A series of novel quaternary ammonium surfactants containing adamantane were designed and synthesized from 1-adamantanecarboxylic acid.The structures of target surfactants were confirmed by 1H NMR,elements analysis and FTIR.Surface properties of these surfactants were investigated.Due to the lipophilicity of adamantane,the critical micelle concentration (CMC) and C20 values of the synthesized quaternary ammonium surfactants are lower than that of conventional quaternary ammonium surfactants.

  3. Reassimilation of ammonium in Lotus japonicus. (United States)

    Betti, Marco; García-Calderón, Margarita; Pérez-Delgado, Carmen M; Credali, Alfredo; Pal'ove-Balang, Peter; Estivill, Guillermo; Repčák, Miroslav; Vega, José M; Galván, Francisco; Márquez, Antonio J


    This review summarizes the most recent results obtained in the analysis of two important metabolic pathways involved in the release of internal sources of ammonium in the model legume Lotus japonicus: photorespiratory metabolism and asparagine breakdown mediated by aparaginase (NSE). The use of photorespiratory mutants deficient in plastidic glutamine synthetase (GS2) enabled us to investigate the transcriptomics and metabolomic changes associated with photorespiratory ammonium accumulation in this plant. The results obtained indicate the existence of a coordinate regulation of genes involved in photorespiratory metabolism. Other types of evidence illustrate the multiple interconnections existing among the photorespiratory pathway and other processes such as intermediate metabolism, nodule function, and secondary metabolism in this plant, all of which are substantially affected in GS2-deficient mutants because of the impairment of the photorespiratory cycle. Finally, the importance of asparagine metabolism in L. japonicus is highlighted because of the fact that asparagine constitutes the vast majority of the reduced nitrogen translocated between different organs of this plant. The different types of NSE enzymes and genes which are present in L. japonicus are described. There is a particular focus on the most abundant K(+)-dependent LjNSE1 isoform and how TILLING mutants were used to demonstrate by reverse genetics the importance of this particular isoform in plant growth and seed production.

  4. Ammonium nitrate: a promising rocket propellant oxidizer (United States)

    Oommen; Jain


    Ammonium nitrate (AN) is extensively used in the area of fertilizers and explosives. It is present as the major component in most industrial explosives. Its use as an oxidizer in the area of propellants, however, is not as extensive as in explosive compositions or gas generators. With the growing demand for environmental friendly chlorine free propellants, many attempts have been made of late to investigate oxidizers producing innocuous combustion products. AN, unlike the widely used ammonium perchlorate, produces completely ecofriendly smokeless products. Besides, it is one of the cheapest and easily available compounds. However, its use in large rocket motors is restricted due to some of its adverse characteristics like hygroscopicity, near room temperature phase transformation involving a volume change, and low burning rate (BR) and energetics. The review is an attempt to consolidate the information available on the various issues pertaining to its use as a solid propellant oxidizer. Detailed discussions on the aspects relating to phase modifications, decomposition chemistry, and BR and energetics of AN-based propellants, are presented. To make the review more comprehensive brief descriptions of the history, manufacture, safety, physical and chemical properties and various other applications of the salt are also included. Copyright 1999 Elsevier Science B.V.

  5. 21 CFR 524.1484e - Neomycin sulfate and polymyxin B sulfate ophthalmic solution. (United States)


    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Neomycin sulfate and polymyxin B sulfate ophthalmic solution. 524.1484e Section 524.1484e Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... DOSAGE FORM NEW ANIMAL DRUGS § 524.1484e Neomycin sulfate and polymyxin B sulfate ophthalmic solution....

  6. 21 CFR 582.1643 - Potassium sulfate. (United States)


    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Potassium sulfate. 582.1643 Section 582.1643 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1643 Potassium sulfate. (a) Product. Potassium sulfate. (b) Conditions of use....

  7. 21 CFR 184.1643 - Potassium sulfate. (United States)


    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Potassium sulfate. 184.1643 Section 184.1643 Food... Specific Substances Affirmed as GRAS § 184.1643 Potassium sulfate. (a) Potassium sulfate (K2SO4, CAS Reg... having a bitter, saline taste. It is prepared by the neutralization of sulfuric acid with...

  8. 21 CFR 582.5443 - Magnesium sulfate. (United States)


    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Magnesium sulfate. 582.5443 Section 582.5443 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5443 Magnesium sulfate. (a) Product. Magnesium sulfate. (b) Conditions of use....

  9. 21 CFR 184.1443 - Magnesium sulfate. (United States)


    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Magnesium sulfate. 184.1443 Section 184.1443 Food... Specific Substances Affirmed as GRAS § 184.1443 Magnesium sulfate. (a) Magnesium sulfate (MgSO4·7H2O, CAS... magnesium oxide, hydroxide, or carbonate with sulfuric acid and evaporating the solution to...

  10. Sulfate transport in Penicillium chrysogenum plasma membranes.


    Hillenga, Dirk J.; Versantvoort, Hanneke J.M.; Driessen, Arnold J. M.; Konings, Wil N.


    Transport studies with Penicillium chrysogenum plasma membranes fused with cytochrome c oxidase liposomes demonstrate that sulfate uptake is driven by the transmembrane pH gradient and not by the transmembrane electrical potential. Ca2+ and other divalent cations are not required. It is concluded that the sulfate transport system catalyzes the symport of two protons with one sulfate anion.

  11. Preparation of Conducting Poly N-methylaniline Microsphere and Its Antibacterial Performance to Sulfate Reducing Bacteria

    Institute of Scientific and Technical Information of China (English)

    LIU Hongfan; HUANG Li; HUANG Zhuo; QI Gongtai; KEI Nanada; Yutaka Harima


    Microspheres of conducting polymers poly N-methylaniline(PNMA)were successfully synthesized through oxidation of N-methylaniline without any template.The average diameter of the M ammonium persulfate in 0.2 M of HCIO4 solution.The size of microspheres can be controlled by changing reaction time and temperature.The acid concentration was critical for the formation of microspheres with smooth surfaces.The excellent antibacterial performance of PNMA in novolac epoxy coating to sulfate reducing bacteria was demonstrated.Moreover,in API media,PNMA inhibited growth of SRB and then reduced the corrosion rate of carbon steel remarkably.


    Institute of Scientific and Technical Information of China (English)

    毛莹博; 方建军; 文娅; 赵文娟; 王珊; 魏志聪


    In this paper, through a series of experiment studies about the different ammonia-ammonium coupling of leaching system for the effect of copper oxide ore leaching, a significant influence sequence of the different ammonia-ammonium coupling of leaching system on the leaching rate of copper is determined as following : ammonia-ammonium carbamate > ammonia-ammonium carbonate > ammonia-ammonium chloride > ammonia-ammonium fluoride > ammonia-ammonium bicarbonate > ammonia-ammonium sulfate. The ammonia-ammonium carbamate leaching system is adopted as the experiment study of high calcium and magnesium, low grade and argillaceous copper oxide ore in Xinjiang Water, and the copper leaching rate is as high as 85. 25% .%通过不同氨-铵浸出体系对氧化铜矿浸出影响的试验研究,确定了不同氨-铵浸出体系对铜浸出率的显著性影响顺序是:氨-氨基甲酸铵>氨-碳酸铵>氨-氯化铵>氨-氟化铵>氨-碳酸氢铵>氨-硫酸铵.采用氨-氨基甲酸铵浸出体系对新疆滴水高钙镁低品位泥质氧化铜矿进行浸出试验,铜浸出率高达85.25%.

  13. Tris(ethylenediaminecobalt(II sulfate

    Directory of Open Access Journals (Sweden)

    Bunlawee Yotnoi


    Full Text Available The structure of the title compound, [CoII(C2H8N23]SO4, the cobalt example of [M(C2H8N23]SO4, is reported. The Co and S atoms are located at the 2d and 2c Wyckoff sites (point symmetry 32, respectively. The Co atom is coordinated by six N atoms of three chelating ethylenediamine molecules generated from half of the ethylenediamine molecule in the asymmetric unit. The O atoms of the sulfate anion are disordered mostly over two crystallographic sites. The third disorder site of O (site symmetry 3 has a site occupancy approaching zero. The H atoms of the ethylenediamine molecules interact with the sulfate anions via intermolecular N—H...O hydrogen-bonding interactions.

  14. Sulfates on Mars: Indicators of Aqueous Processes (United States)

    Bishop, Janice L.; Lane, Melissa D.; Dyar, M. Darby; Brown, Adrian J.


    Recent analyses by MER instruments at Meridiani Planum and Gusev crater and the OMEGA instrument on Mars Express have provided detailed information about the presence of sulfates on Mars [1,2,3]. We are evaluating these recent data in an integrated multi-disciplinary study of visible-near-infrared, mid-IR and Mossbauer spectra of several sulfate minerals and sulfate-rich analog sites. Our analyses suggest that hydrated iron sulfates may account for features observed in Mossbauer and mid-IR spectra of Martian soils [4]. The sulfate minerals kieserite, gypsum and other hydrated sulfates have been identified in OMEGA spectra in the layered terrains in Valles Marineris and Terra Meridiani [2]. These recent discoveries emphasize the importance of studying sulfate minerals as tracers of aqueous processes. The sulfate-rich rock outcrops observed in Meridiani Planum may have formed in an acidic environment similar to acid rock drainage environments on Earth [5]. Because microorganisms typically are involved in the oxidation of sulfides to sulfates in terrestrial sites, sulfate-rich rock outcrops on Mars may be a good location to search for evidence of past life on that planet. Whether or not life evolved on Mars, following the trail of sulfate minerals will lead to a better understanding of aqueous processes and chemical weathering.

  15. Unsteady growth of ammonium chloride dendrites (United States)

    Martyushev, L. M.; Terentiev, P. S.; Soboleva, A. S.


    Growth of ammonium chloride dendrites from aqueous solution is experimentally investigated. The growth rate υ and the radius ρ of curvature of branches are measured as a function of the relative supersaturation Δ for steady and unsteady growth conditions. It is shown that the experimental results are quantitatively described by the dependences ρ=a/Δ+b, υ=cΔ2, where the factors for primary branches are a=(1.3±0.2)·10-7 m, b=(2.5±0.4)·10-7 m, and c=(2.2±0.3)·10-4 m/s. The factor c is found to be approximately 7 times smaller for the side branches than that for the primary branches.

  16. Efficient cellulose solvent: quaternary ammonium chlorides. (United States)

    Kostag, Marc; Liebert, Tim; El Seoud, Omar A; Heinze, Thomas


    Pure quaternary tetraalkylammonium chlorides with one long alkyl chain dissolved in various organic solvents constitute a new class of cellulose solvents. The electrolytes are prepared in high yields and purity by Menshutkin quaternization, an inexpensive and easy synthesis route. The pure molten tetraalkylammonium chlorides dissolve up to 15 wt% of cellulose. Cosolvents, including N,N-dimethylacetamide (DMA), may be added in large excess, leading to a system of decreased viscosity. Contrary to the well-established solvent DMA/LiCl, cellulose dissolves in DMA/quaternary ammonium chlorides without any pretreatment. Thus, the use of the new solvent avoids some disadvantages of DMA/LiCl and ionic liquids, the most extensively employed solvents for homogeneous cellulose chemistry.

  17. Hydration Structure of the Quaternary Ammonium Cations

    KAUST Repository

    Babiaczyk, Wojtek Iwo


    Two indicators of the hydropathicity of small solutes are introduced and tested by molecular dynamics simulations. These indicators are defined as probabilities of the orientation of water molecules\\' dipoles and hydrogen bond vectors, conditional on a generalized distance from the solute suitable for arbitrarily shaped molecules. Using conditional probabilities, it is possible to distinguish features of the distributions in close proximity of the solute. These regions contain the most significant information on the hydration structure but cannot be adequately represented by using, as is usually done, joint distance-angle probability densities. Our calculations show that using our indicators a relative hydropathicity scale for the interesting test set of the quaternary ammonium cations can be roughly determined. © 2010 American Chemical Society.

  18. Chondroitin Sulfate Perlecan Enhances Collagen Fibril Formation

    DEFF Research Database (Denmark)

    Kvist, A. J.; Johnson, A. E.; Mörgelin, M.


    produced in the presence of perlecan. Interestingly, the enhancement of collagen fibril formation is independent on the core protein and is mimicked by chondroitin sulfate E but neither by chondroitin sulfate D nor dextran sulfate. Furthermore, perlecan chondroitin sulfate contains the 4,6-disulfated......Inactivation of the perlecan gene leads to perinatal lethal chondrodysplasia. The similarity to the phenotypes of the Col2A1 knock-out and the disproportionate micromelia mutation suggests perlecan involvement in cartilage collagen matrix assembly. We now present a mechanism for the defect...... in collagen type II fibril assembly by perlecan-null chondrocytes. Cartilage perlecan is a heparin sulfate or a mixed heparan sulfate/chondroitin sulfate proteoglycan. The latter form binds collagen and accelerates fibril formation in vitro, with more defined fibril morphology and increased fibril diameters...

  19. 21 CFR 73.1298 - Ferric ammonium ferrocyanide. (United States)


    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Ferric ammonium ferrocyanide. 73.1298 Section 73.1298 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL...) Identity. (1) The color additive ferric ammonium ferrocyanide is the blue pigment obtained by...

  20. How to make a living from anaerobic ammonium oxidation

    NARCIS (Netherlands)

    Kartal, B.; De Almeida, N.M.; Maalcke, W.J.; Op den Camp, H.J.M.; Jetten, M.S.M.; Keltjens, J.T.


    Anaerobic ammonium-oxidizing (anammox) bacteria primarily grow by the oxidation of ammonium coupled to nitrite reduction, using CO2 as the sole carbon source. Although they were neglected for a long time, anammox bacteria are encountered in an enormous species (micro)diversity in virtually any anoxi

  1. Sulfation and biological activities of konjac glucomannan. (United States)

    Bo, Surina; Muschin, Tegshi; Kanamoto, Taisei; Nakashima, Hideki; Yoshida, Takashi


    The sulfation of konjac glucomannan and its anti-HIV and blood anticoagulant activities were investigated. Konjac glucomannan is a polysaccharide occurring naturally in konjac plant tubers and has high molecular weights. Solubility in water is very low, and the aqueous solutions at low concentrations have high viscosity. Before sulfation, hydrolysis by diluted sulfuric acid was carried out to decrease the molecular weights of M¯n=19.2 × 10(4)-0.2 × 10(4). Sulfation with piperidine-N-sulfonic acid or SO3-pyridine complex gave sulfated konjac glucomannans with molecular weights of M¯n=1.0 × 10(4)-0.4 × 10(4) and degrees of sulfation (DS) of 1.3-1.4. It was found that the sulfated konjac glucomannans had potent anti-HIV activity at a 50% effective concentration, (EC50) of 1.2-1.3 μg/ml, which was almost as high as that of an AIDS drug, ddC, whose EC50=3.2 μg/ml, and moderate blood anticoagulant activity, AA=0.8-22.7 units/mg, compared to those of standard sulfated polysaccharides, curdlan (10 units/mg) and dextran (22.7 units/mg) sulfates. Structural analysis of sulfated konjac glucomannans with negatively charged sulfated groups was performed by high resolution NMR, and the interaction between poly-l-lysine with positively charged amino groups as a model compound of proteins and peptides was measured by surface plasmon resonance measurement, suggesting that the sulfated konjac glucomannans had a high binding stability on immobilized poly-l-lysine. The binding of sulfated konjac glucomannan was concentration-dependent, and the biological activity of the sulfated konjac glucomannans may be due to electrostatic interaction between the sulfate and amino groups.

  2. Ammonium removal from landfill leachate by anodic oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Cabeza, Adelaida [Department of Chemical Engineering, University of Cantabria, Avda. de los Castros s/n. 39005 Santander (Spain); Urtiaga, Ane [Department of Chemical Engineering, University of Cantabria, Avda. de los Castros s/n. 39005 Santander (Spain)]. E-mail:; Rivero, Maria-Jose [Department of Chemical Engineering, University of Cantabria, Avda. de los Castros s/n. 39005 Santander (Spain); Ortiz, Inmaculada [Department of Chemical Engineering, University of Cantabria, Avda. de los Castros s/n. 39005 Santander (Spain)


    The feasibility of removing ammonium from landfill leachates by electrochemical oxidation was studied. Raw leachates and biologically/physico-chemically pretreated leachates from a municipal landfill site were treated. Boron doped diamond was used as anode and stainless steel as cathode, both electrodes with an area of 70 cm{sup 2}. The effects of the applied current density (15-90 mA cm{sup -2}), the initial ammonium concentration (480-2000 mg L{sup -1}), and the initial chloride concentration were experimentally studied. Total ammonium removal was obtained after 360 min of processing and almost half of the initial ammonium nitrogen was oxidized to nitrate. On the other hand, the concentration of chloride enhanced the rate of ammonium oxidation. In addition, the amount of N-NH{sub 4} {sup +} transformed into N-NO{sub 3} {sup -} decreased when additional chloride was provided.

  3. Seasonal patterns of ammonium regeneration from size-fractionated microheterotrophs (United States)

    Maguer, Jean-François; L'Helguen, Stéphane; Madec, Christian; Le Corre, Pierre


    Ammonium regeneration by size-fractionated plankton was measured for 1 year at a coastal station in the shallow well-mixed waters of the western English Channel. Rates of ammonium regeneration in the Journal of Plankton Research, 18, 355-370). Total ammonium regenerated in a year by the microheterotrophs was 15 g N m -2, equivalent to about 60% of the total nitrogen uptake. Microplankton (200-15 μm) accounted for about 50% of the regeneration measured between early spring and late summer. Percent contribution of nanoplankton to total ammonium regeneration varied considerably between the seasons, from very high (83-88%) levels in winter to very low (2-13%) levels in summer. Contribution by picoplankton (nano- and picoplankton fractions, appears to be different from that in deep well-mixed waters. Here, the relative contribution of ciliates and bacteria to ammonium regeneration shows little variation with an increase in macrozooplankton biomass.

  4. 76 FR 49449 - Continuation of Antidumping Duty Order on Solid Fertilizer Grade Ammonium Nitrate From the... (United States)


    ... Nitrate From the Russian Federation AGENCY: Import Administration, International Trade Administration... duty investigation on solid fertilizer grade ammonium nitrate (``ammonium nitrate'') from the Russian... and the ITC instituted a second sunset review of the ammonium nitrate suspended investigation....

  5. 76 FR 23569 - Termination of the Suspension Agreement on Solid Fertilizer Grade Ammonium Nitrate From the... (United States)


    ... Nitrate From the Russian Federation and Notice of Antidumping Duty Order AGENCY: Import Administration... (``AD'') Investigation on Solid Fertilizer Grade Ammonium Nitrate from the Russian Federation (``the... determine whether imports of solid fertilizer grade ammonium nitrate (``ammonium nitrate'') from Russia...

  6. Inhibition of synthesis of heparan sulfate by selenate: Possible dependence on sulfation for chain polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Dietrich, C.P.; Nader, H.B. (Paulist School of Medicine, Sao Paulo (Brazil)); Buonassisi, V.; Colburn, P. (W. Alton Jones Cell Science Center, Lake Placid, NY (USA))


    Selenate, a sulfation inhibitor, blocks the synthesis of heparan sulfate and chondroitin sulfate by cultured endothelial cells. In contrast, selenate does not affect the production of hyaluronic acid, a nonsulfated glycosaminoglycan. No differences in molecular weight, ({sup 3}H)glucosamine/({sup 35}S)sulfuric acid ratios, or disaccharide composition were observed when the heparan sulfate synthesized by selenate-treated cells was compared with that of control cells. The absence of undersulfated chains in preparations from cultures exposed to selenate supports the concept that, in the intact cell, the polymerization of heparan sulfate might be dependent on the sulfation of the saccharide units added to the growing glycosaminoglycan chain.

  7. Near-Barrierless Ammonium Bisulfate Formation via a Loop-Structure Promoted Proton-Transfer Mechanism on the Surface of Water. (United States)

    Li, Lei; Kumar, Manoj; Zhu, Chongqin; Zhong, Jie; Francisco, Joseph S; Zeng, Xiao Cheng


    In the atmosphere, a well-known and conventional pathway toward the formation of ammonium sulfate is through the neutralization of sulfuric acid with ammonia (NH3) in water droplets. Here, we present direct ab initio molecular dynamics simulation evidence of the formation of ammonium bisulfate (NH4HSO4) from the hydrated NH3 and SO3 molecules in a water trimer as well as on the surface of a water droplet. This reaction suggests a new mechanism for the formation of ammonium sulfate in the atmosphere, especially when the concentration of NH3 is high (e.g., ∼10 μg m(-3)) in the air. Contrary to the water monomer and dimer, the water trimer enables near-barrierless proton transfer via the formation of a unique loop structure around the reaction center. The formation of the loop structure promotes the splitting of a water molecule in the proton-transfer center, resulting in the generation a NH4(+)/HSO4(-) ion pair. The loop-structure promoted proton-transfer mechanism is expected to be ubiquitous on the surface of cloud droplets with adsorbed NH3 and SO3 molecules and, thus, may play an important role in the nucleation of aerosol particles (e.g., fine particles PM2.5) in water droplets.

  8. Evaluating Deterioration of Concrete by Sulfate Attack

    Institute of Scientific and Technical Information of China (English)


    Effects of factors such as water to cement ratio, fly ash and silica fume on the resistance of concrete to sulfate attack were investigated by dry-wet cycles and immersion method. The index of the resistance to sulfate attack was used to evaluate the deterioration degree of concrete damaged by sulfate. The relationship between the resistance of concrete to sulfate attack and its permeability/porosity were analyzed as well as its responding mechanism. Results show that the depth of sulfate crystal attack from surface to inner of concrete can be reduced by decreasing w/c and addition of combining fly ash with silica fume. The variation of relative elastic modulus ratio and relative flexural strength ratio of various specimens before and after being subjected to sulfate attack was compared.

  9. Depolymerization of sulfated polysaccharides under hydrothermal conditions. (United States)

    Morimoto, Minoru; Takatori, Masaki; Hayashi, Tetsuya; Mori, Daiki; Takashima, Osamu; Yoshida, Shinichi; Sato, Kimihiko; Kawamoto, Hitoshi; Tamura, Jun-ichi; Izawa, Hironori; Ifuku, Shinsuke; Saimoto, Hiroyuki


    Fucoidan and chondroitin sulfate, which are well known sulfated polysaccharides, were depolymerized under hydrothermal conditions (120-180°C, 5-60min) as a method for the preparation of sulfated polysaccharides with controlled molecular weights. Fucoidan was easily depolymerized, and the change of the molecular weight values depended on the reaction temperature and time. The degree of sulfation and IR spectra of the depolymerized fucoidan did not change compared with those of untreated fucoidan at reaction temperatures below 140°C. However, fucoidan was partially degraded during depolymerization above 160°C. Nearly the same depolymerization was observed for chondroitin sulfate. These results indicate that hydrothermal treatment is applicable for the depolymerization of sulfated polysaccharides, and that low molecular weight products without desulfation and deformation of the initial glycan structures can be obtained under mild hydrothermal conditions.

  10. Subcellular localization of ammonium transporters in Dictyostelium discoideum

    Directory of Open Access Journals (Sweden)

    Davis Carter T


    Full Text Available Abstract Background With the exception of vertebrates, most organisms have plasma membrane associated ammonium transporters which primarily serve to import a source of nitrogen for nutritional purposes. Dictyostelium discoideum has three ammonium transporters, Amts A, B and C. Our present work used fluorescent fusion proteins to determine the cellular localization of the Amts and tested the hypothesis that the transporters mediate removal of ammonia generated endogenously from the elevated protein catabolism common to many protists. Results Using RFP and YFP fusion constructs driven by the actin 15 promoter, we found that the three ammonium transporters were localized on the plasma membrane and on the membranes of subcellular organelles. AmtA and AmtB were localized on the membranes of endolysosomes and phagosomes, with AmtB further localized on the membranes of contractile vacuoles. AmtC also was localized on subcellular organelles when it was stabilized by coexpression with either the AmtA or AmtB fusion transporter. The three ammonium transporters exported ammonia linearly with regard to time during the first 18 hours of the developmental program as revealed by reduced export in the null strains. The fluorescently tagged transporters rescued export when expressed in the null strains, and thus they were functional transporters. Conclusion Unlike ammonium transporters in most organisms, which import NH3/NH4+ as a nitrogen source, those of Dictyostelium export ammonia/ammonium as a waste product from extensive catabolism of exogenously derived and endogenous proteins. Localization on proteolytic organelles and on the neutral contractile vacuole suggests that Dictyostelium ammonium transporters may have unique subcellular functions and play a role in the maintenance of intracellular ammonium distribution. A lack of correlation between the null strain phenotypes and ammonia excretion properties of the ammonium transporters suggests that it is not

  11. [Reasons of high concentration ammonium in Yellow River, China]. (United States)

    Zhang, Xue-qing; Xia, Xing-hui; Yang, Zhi-feng


    Ammonium nitrogen contamination is one of the major problems of the Yellow River in China. The speciation, concentration and sources of nitrogen compounds as well as the water environment conditions of the Yellow River had been analyzed to study the reasons for the fact that the ammonium nitrogen concentration was above the water quality standard. In addition, laboratory experiments had been carried out to investigate the effects of suspended sediment (SS) on nitrification rate. The results indicated that the presence of SS could accelerate the nitrification process, therefore, the effects of SS on nitrification rate was not the reason for the high level of ammonium nitrogen in the river. The excessive and continuous input of nitrogen contaminants to the river was the fundamental reason for the high concentration of ammonium nitrogen. Organic and ammonium nitrogen with high concentration inhibitted the nitrification processes. When the initial NH4+ -N concentrations were 10.1, 18.4 and 28.2 mg/L, nitrification efficiencies were 17.4%, 13.0% and 2.5%, respectively. When the initial organic nitrogen concentrations were 5.5 and 8.6 mg/L, the maximum concentrations of ammonium nitrogen produced by the oxidation of organic nitrogen would reach 0.47 and 1.69 mg/L and they would last for 2 days and 6 days, respectively. The oxygen-consuming organics and toxic substance existing in the river water could inhibit the activity of nitrifying bacteria, and thus lead to the accumulation of ammonium nitrogen. In addition, the high pH value of river water resulted in the high concentration of nonionic ammonium nitrogen which would reduce the activity of nitrifying bacteria and decrease the nitrification rates. Besides, low river runoff, low SS content and low activity of nitrifying bacteria resulted in the high level of ammonium nitrogen of the river in the low water season.

  12. Modelling an Ammonium Transporter with SCLS

    Directory of Open Access Journals (Sweden)

    Angelo Troina


    Full Text Available The Stochastic Calculus of Looping Sequences (SCLS is a recently proposed modelling language for the representation and simulation of biological systems behaviour. It has been designed with the aim of combining the simplicity of notation of rewrite systems with the advantage of compositionality. It also allows a rather simple and accurate description of biological membranes and their interactions with the environment.In this work we apply SCLS to model a newly discovered ammonium transporter. This transporter is believed to play a fundamental role for plant mineral acquisition, which takes place in the arbuscular mycorrhiza, the most wide-spread plant-fungus symbiosis on earth. Due to its potential application in agriculture this kind of symbiosis is one of the main focuses of the BioBITs project. In our experiments the passage of NH3 / NH4+ from the fungus to the plant has been dissected in known and hypothetical mechanisms; with the model so far we have been able to simulate the behaviour of the system under different conditions. Our simulations confirmed some of the latest experimental results about the LjAMT2;2 transporter. The initial simulation results of the modelling of the symbiosis process are promising and indicate new directions for biological investigations.

  13. Antimicrobial Polymeric Materials with Quaternary Ammonium and Phosphonium Salts

    Directory of Open Access Journals (Sweden)

    Yan Xue


    Full Text Available Polymeric materials containing quaternary ammonium and/or phosphonium salts have been extensively studied and applied to a variety of antimicrobial-relevant areas. With various architectures, polymeric quaternary ammonium/phosphonium salts were prepared using different approaches, exhibiting different antimicrobial activities and potential applications. This review focuses on the state of the art of antimicrobial polymers with quaternary ammonium/phosphonium salts. In particular, it discusses the structure and synthesis method, mechanisms of antimicrobial action, and the comparison of antimicrobial performance between these two kinds of polymers.

  14. Parameterization of the Optical Properties of Sulfate Aerosols in the Infrared. (United States)

    Li, J.; Min, Qilong


    Parameterizations of absorptance depth for ammonium sulfate [(NH4)2SO4], ammonium bisulfate (NH4HSO4), and sulfuric acid (H2SO4) in the infrared are provided for an eight-band model (covering 340-2500 cm1) and for 32 individual wavenumbers in order to generate other band schemes. The parameterization is simple in form and in its dependence on relative humidity.It is found that the aerosol surface infrared forcing can cancel about 12%-24% aerosol surface solar forcing in a clear sky condition. Also the existence of clouds could enhance the ratio of aerosol surface infrared forcing to the aerosol surface solar forcing. In contrast to the solar case, a small mode size distribution does not always produce a larger aerosol surface forcing. Also it is found that the aerosol surface forcing is dependent on the aerosol location. Very simple analysis is presented to help understand the related physics on sulfate aerosol infrared radiative forcing.

  15. Origin of high ammonium, arsenic and boron concentrations in the proximity of a mine: Natural vs. anthropogenic processes

    Energy Technology Data Exchange (ETDEWEB)

    Scheiber, Laura, E-mail: [Institute of Environmental Assessment and Water Research, CSIC, Jordi Girona 18. E-08034 Barcelona (Spain); Ayora, Carlos; Vázquez-Suñé, Enric [Institute of Environmental Assessment and Water Research, CSIC, Jordi Girona 18. E-08034 Barcelona (Spain); Cendón, Dioni I. [Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia); School of Biological, Earth and Environmental Sciences (BEES), University of New South Wales (UNSW), NSW 2052 (Australia); Soler, Albert [Departament de Cristallografia, Mineralogia i Dipòsits Minerals, Facultat de Geologia, Universitat de Barcelona, C/Martí Franquès, sn., Barcelona (Spain); Baquero, Juan Carlos [Cobre Las Cruces S.A., Carretera SE-3410 km 4, 41860 Gerena, Sevilla (Spain)


    High ammonium (NH{sub 4}), arsenic (As) and boron (B) concentrations are found in aquifers worldwide and are often related to human activities. However, natural processes can also lead to groundwater quality problems. High NH{sub 4}, As and B concentrations have been identified in the confined, deep portion of the Niebla-Posadas aquifer, which is near the Cobre Las Cruces (CLC) mining complex. The mine has implemented a Drainage and Reinjection System comprising two rings of wells around the open pit mine, were the internal ring drains and the external ring is used for water reinjection into the aquifer. Differentiating geogenic and anthropogenic sources and processes is therefore crucial to ensuring good management of groundwater in this sensitive area where groundwater is extensively used for agriculture, industry, mining and human supply. No NH{sub 4}, As and B are found in the recharge area, but their concentrations increase with depth, salinity and residence time of water in the aquifer. The increased salinity down-flow is interpreted as the result of natural mixing between infiltrated meteoric water and the remains of connate waters (up to 8%) trapped within the pores. Ammonium and boron are interpreted as the result of marine solid organic matter degradation by the sulfate dissolved in the recharge water. The light δ{sup 15}N{sub NH4} values confirm that its origin is linked to marine organic matter. High arsenic concentrations in groundwater are interpreted as being derived from reductive dissolution of As-bearing goethite by dissolved organic matter. The lack of correlation between dissolved Fe and As is explained by the massive precipitation of siderite, which is abundantly found in the mineralization. Therefore, the presence of high arsenic, ammonium and boron concentrations is attributed to natural processes. Ammonium, arsenic, boron and salinity define three zones of groundwater quality: the first zone is close to the recharge area and contains water

  16. Origin of high ammonium, arsenic and boron concentrations in the proximity of a mine: Natural vs. anthropogenic processes. (United States)

    Scheiber, Laura; Ayora, Carlos; Vázquez-Suñé, Enric; Cendón, Dioni I; Soler, Albert; Baquero, Juan Carlos


    High ammonium (NH4), arsenic (As) and boron (B) concentrations are found in aquifers worldwide and are often related to human activities. However, natural processes can also lead to groundwater quality problems. High NH4, As and B concentrations have been identified in the confined, deep portion of the Niebla-Posadas aquifer, which is near the Cobre Las Cruces (CLC) mining complex. The mine has implemented a Drainage and Reinjection System comprising two rings of wells around the open pit mine, were the internal ring drains and the external ring is used for water reinjection into the aquifer. Differentiating geogenic and anthropogenic sources and processes is therefore crucial to ensuring good management of groundwater in this sensitive area where groundwater is extensively used for agriculture, industry, mining and human supply. No NH4, As and B are found in the recharge area, but their concentrations increase with depth, salinity and residence time of water in the aquifer. The increased salinity down-flow is interpreted as the result of natural mixing between infiltrated meteoric water and the remains of connate waters (up to 8%) trapped within the pores. Ammonium and boron are interpreted as the result of marine solid organic matter degradation by the sulfate dissolved in the recharge water. The light δ(15)NNH4 values confirm that its origin is linked to marine organic matter. High arsenic concentrations in groundwater are interpreted as being derived from reductive dissolution of As-bearing goethite by dissolved organic matter. The lack of correlation between dissolved Fe and As is explained by the massive precipitation of siderite, which is abundantly found in the mineralization. Therefore, the presence of high arsenic, ammonium and boron concentrations is attributed to natural processes. Ammonium, arsenic, boron and salinity define three zones of groundwater quality: the first zone is close to the recharge area and contains water of sufficient quality for

  17. Modeling of ferric sulfate decomposition and sulfation of potassium chloride during grate‐firing of biomass

    DEFF Research Database (Denmark)

    Wu, Hao; Jespersen, Jacob Boll; Jappe Frandsen, Flemming


    Ferric sulfate is used as an additive in biomass combustion to convert the released potassium chloride to the less harmful potassium sulfate. The decomposition of ferric sulfate is studied in a fast heating rate thermogravimetric analyzer and a volumetric reaction model is proposed to describe th...

  18. Involvement of highly sulfated chondroitin sulfate in the metastasis of the Lewis lung carcinoma cells.

    NARCIS (Netherlands)

    Li, F.; Dam, G.B. ten; Murugan, S.; Yamada, S.; Hashiguchi, T.; Mizumoto, S.; Oguri, K.; Okayama, M.; Kuppevelt, A.H.M.S.M. van; Sugahara, K.


    The altered expression of cell surface chondroitin sulfate (CS) and dermatan sulfate (DS) in cancer cells has been demonstrated to play a key role in malignant transformation and tumor metastasis. However, the functional highly sulfated structures in CS/DS chains and their involvement in the process

  19. Discovery of a Heparan sulfate 3- o -sulfation specific peeling reaction

    NARCIS (Netherlands)

    Huang, Yu; Mao, Yang; Zong, Chengli; Lin, Cheng; Boons, Geert Jan; Zaia, Joseph


    Heparan sulfate (HS) 3-O-sulfation determines the binding specificity of HS/heparin for antithrombin III and plays a key role in herpes simplex virus (HSV) infection. However, the low natural abundance of HS 3-O-sulfation poses a serious challenge for functional studies other than the two cases ment

  20. 14N NQR and relaxation in ammonium nitrate (United States)

    Stephenson, David


    The complete 14N nuclear quadrupole resonance (NQR) spectrum of ammonium nitrate is presented recorded using two double resonance techniques - double contact cross relaxation and zero field NQR. The spectra gave the quadrupole coupling constant (Qcc) and asymmetry parameter ( η) values for the nitro of 611 kHz, 0.229 and that for the ammonium nitrogen of 242 kHz, 0.835. The three relaxation transition probabilities have been determined for both the nitro and ammonium nitrogen atoms. The bi-exponential relaxation times (T 1) were measured at 295 K. The values for nitro are 16.9 s and 10.5 s and that of the ammonium are 23.0 s and 16.4 s.

  1. Synthesis and Antibacterial Activity of Novel Quaternary Ammonium Pyridoxine Derivatives. (United States)

    Shtyrlin, Nikita V; Sapozhnikov, Sergey V; Koshkin, Sergey A; Iksanova, Alfiya G; Sabirov, Arthur H; Kayumov, Airat R; Nureeva, Aliya A; Zeldi, Marina I; Shtyrlin, Yurii G


    A series of 26 quaternary ammonium pyridoxine derivatives were synthesized and their cytotoxicity and antibacterial activities against clinically relevant bacterial strains were tested in vitro. The antibacterial activity of mono-ammonium salts increased with the rise of the lipophilicity and compound 3,3,5-trimethyl-8,8-dioctyl-1,7,8,9-tetrahydro-[1,3]dioxino[5,4-d]pyrrolo[3,4-b]pyridin-8-ium chloride (2d) reaches a maximum among them. Bis-ammonium salt of pyridoxine 4 with two dimethyloctylamine groups also demonstrated high antibacterial activity despite lower lipophilicity. The results of MTT assay indicated that HEK 293 cells were more sensitive than HSF to quaternary ammonium pyridoxine derivatives. Compounds 2d and 4 did not induce the damage of the DNA and might be of interest in the development of new antimicrobials.

  2. Direct esterification of ammonium salts of carboxylic acids (United States)

    Halpern, Yuval


    A non-catalytic process for producing esters, the process comprising reacting an ammonium salt of a carboxylic acid with an alcohol and removing ammonia from the reaction mixture. Selectivities for the desired ester product can exceed 95 percent.

  3. Ammonium removal by modified zeolite from municipal wastewater

    Institute of Scientific and Technical Information of China (English)

    ZHAO Ya-ping; GAO Ting-yao; JIANG Shang-ying; CAO Da-wen


    Ammonium removal by modified zeolite, H-form and Na-form zeolite, were examined by batch-type methods. The adsorption of ammonium on modified zeolite was exothermic process. The saturation adsorption capacity of ammonium on H-form and Na-form zeolite were 21.23 and 41.15 mg/g, respectively. After ten times adsorption- desorption-readsorption cycles the standard deviations of H-form and Na-form zeolite were 6.34% and 6.59%. The zeolite adsorption process has proved cost effective and practical in reducing ammonium by H-form and Na-form zeolite in municipal wastewater from concentration 27.68 mg/L to 2.80 mg/L and 5.91 mg/L.

  4. {sup 14}N NQR and relaxation in ammonium nitrate

    Energy Technology Data Exchange (ETDEWEB)

    Stephenson, David, E-mail: [University of the West Indies, Chemistry Department (Trinidad and Tobago)


    The complete {sup 14}N nuclear quadrupole resonance (NQR) spectrum of ammonium nitrate is presented recorded using two double resonance techniques – double contact cross relaxation and zero field NQR. The spectra gave the quadrupole coupling constant (Qcc) and asymmetry parameter (η) values for the nitro of 611 kHz, 0.229 and that for the ammonium nitrogen of 242 kHz, 0.835. The three relaxation transition probabilities have been determined for both the nitro and ammonium nitrogen atoms. The bi-exponential relaxation times (T {sub 1}) were measured at 295 K. The values for nitro are 16.9 s and 10.5 s and that of the ammonium are 23.0 s and 16.4 s.

  5. Fixed Ammonium Content and Maximum Capacity of Ammonium Fixation in Major Types of Tillage Soils in Hunan Province, China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yang-zhu; HUANG Shun-hong; WAN Da-juan; HUANG Yun-xiang; ZHOU Wei-jun; ZOU Ying-bin


    In order to understand the status of fixed ammonium, fixed ammonium content, maximum capacity of ammonium fixation, and their influencing factors in major types of tillage soils of Hunan Province, China, were studied with sampling on fields, and laboratory incubation and determination. The main results are summarized as follows: (1) Content of fixed ammonium in the tested soils varies greatly with soil use pattern and the nature of parent material. For the paddy soils, it ranges from 135.4 ± 57.4 to 412.8±32.4 mg kg-1, with 304.7±96.7 mg kg-1 in average; while it ranges from 59.4 to 435.7 mg kg-1, with 230.1 ± 89.2 mg kg1 in average for the upland soils. The soils developed from limnic material and slate had higher fixed ammonium content than the soils developed from granite. The percentage of fixed ammonium to total N in the upland soils is always higher than that in the paddy soils. It ranges from 6.1 ± 3.6% to 16.6 ±4.6%, with 14.0% ± 5.1% in average for the paddy soils and it amounted to 5.8 ±2.0% to 40.1 ± 17.8%, with 23.5 ± 14.2% in average for upland soils. (2) The maximum capacity of ammonium fixation has the same trend with the fixed ammonium content in the tested soils. For all the tested soils, the percentage of recently fixed ammonium to maximum capacity of ammonium fixation is always bellow 20% and it may be due to the fact that the soils have high fertility and high saturation of ammonium-fixing site. (3) The clay content and clay composition in the tested soils are the two important factors influe ncing their fixed ammonium content and maximum capacity of ammonium fixation. The results showed that hydrous mica is the main 2:1 type clay mineral in <0.02 mm clay of the paddy soils, and its content in 0.02-0.002 mm clay is much higher than that in < 0.002 mm clay of the soils. The statistical analysis showed that both the fixed ammonium content and the maximum capacity of ammonium fixation of the paddy soils were positively correlated with

  6. Ammonium Metabolism Enzymes Aid Helicobacter pylori Acid Resistance



    The gastric pathogen Helicobacter pylori possesses a highly active urease to support acid tolerance. Urea hydrolysis occurs inside the cytoplasm, resulting in the production of NH3 that is immediately protonated to form NH4+. This ammonium must be metabolized or effluxed because its presence within the cell is counterproductive to the goal of raising pH while maintaining a viable proton motive force (PMF). Two compatible hypotheses for mitigating intracellular ammonium toxicity include (i) th...

  7. 食盐抗结剂柠檬酸铁铵的合成方法%Synthesis of Ferric Ammonium Citrate

    Institute of Scientific and Technical Information of China (English)

    王宇; 闫静; 王学炜; 李泽淳


    Ferrous sulfate was oxidated by hydrogen peroxide to synthesize iron hydroxide, then iron hydroxide reacted with ammonium citrate to prepare ferric ammonium citrate. The conditions which affected the iron content of product, included preparation of iron hydroxide, reaction time, temperature and drying methods, were discussed. The optimum technological conditions were obtained.%以硫酸亚铁为原料,双氧水为氧化剂制备氢氧化铁,再与柠檬酸铵反应制得柠檬酸铁铵。考察了氢氧化铁制备条件、反应时间、反应温度、干燥方式对产品含铁量的影响,确定了最佳工艺条件。

  8. Mutagenicity of quaternary ammonium salts containing carbohydrate moieties

    Energy Technology Data Exchange (ETDEWEB)

    Dmochowska, Barbara [Department of Carbohydrate Chemistry, University of Gdansk, Sobieskiego 18, 80-952 Gdansk (Poland); Piosik, Jacek; Woziwodzka, Anna [Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Kladki 24, 80-822 Gdansk (Poland); Sikora, Karol; Wisniewski, Andrzej [Department of Carbohydrate Chemistry, University of Gdansk, Sobieskiego 18, 80-952 Gdansk (Poland); Wegrzyn, Grzegorz, E-mail: [Department of Molecular Biology, University of Gdansk, Kladki 24, 80-822 Gdansk (Poland)


    Highlights: {yields} A series of quaternary ammonium salts containing carbohydrate moieties, with configuration D-galacto, D-gluco and D-manno, was synthesized and characterized. {yields} The quaternary ammonium salts containing carbohydrate moieties revealed potent mutagenic activities, as assessed by using the Vibrio harveyi bioluminescence mutagenicity test. {yields} The N-[2-(D-glycopyranosyloxy)ethyl]-N,N,N-trimethylaminium salts were of the highest activity in the mutagenicity assay. {yields} We suggest that quaternary ammonium salts may be more hazardous than previously supposed. - Abstract: Quaternary ammonium salts are widely used in industrial, agricultural, healthcare and domestic applications. They are believed to be safe compounds, with little or no health hazard to humans. However, in this report, we demonstrate that a series of newly synthesized quaternary ammonium salts containing carbohydrate moieties reveal potent mutagenic activities, as assessed by using the Vibrio harveyi bioluminescence mutagenicity test. D-Gluco- and D-galacto-derivatives were found to have a higher mutagenic potential than D-manno-derivatives. Among the former groups of compounds, the N-[2-(D-glycopyranosyloxy)ethyl]-N,N,N-trimethylaminium salts were of the highest activity in the mutagenicity assay. These results suggest that the safety of quaternary ammonium salts may be lower than previously supposed, indicating a need for testing such compounds for their mutagenicity.

  9. Fucoidans - sulfated polysaccharides of brown algae

    Energy Technology Data Exchange (ETDEWEB)

    Usov, Anatolii I; Bilan, M I [N.D.Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow (Russian Federation)


    The methods of isolation of fucoidans and determination of their chemical structures are reviewed. The fucoidans represent sulfated polysaccharides of brown algae, the composition of which varies from simple fucan sulfates to complex heteropolysaccharides. The currently known structures of such biopolymers are presented. A variety of the biological activities of fucoidans is briefly summarised.

  10. Fucoidans — sulfated polysaccharides of brown algae (United States)

    Usov, Anatolii I.; Bilan, M. I.


    The methods of isolation of fucoidans and determination of their chemical structures are reviewed. The fucoidans represent sulfated polysaccharides of brown algae, the composition of which varies from simple fucan sulfates to complex heteropolysaccharides. The currently known structures of such biopolymers are presented. A variety of the biological activities of fucoidans is briefly summarised.

  11. The partitioning of Nitric Acid between the gas phase and condensed phase of aqueous sulfate aerosols. (United States)

    Mentel, T. F.; Folkers, M.; Sebald, H.; Wahner, A.


    The heterogeneous hydrolysis of N2O_5 on aqueous aerosol surfaces is an important source of atmospheric HNO3. We generated HNO3 by heterogeneous hydrolysis of N2O_5 on aqueous ammonium and sodium sulfate aerosols and studied its partitioning between the gas phase and the aerosol phase. The experiments were performed in the large aerosol chamber at the FZ-Jülich at several relative humidities. Gas phase processes and the composition of the aerosols were monitored on-line simultaneously by FTIR spectroscopy and by Steam Jet Aerosol Collection/Ion Chromatography. The aerosol size distributions in the range of 20 nm to 5 μ m were measured by differential electromobility classification and by aerodynamic particle sizing. In the presence of aqueous bisulfate and sulfate aerosols a fast heterogeneous formation HNO3 is observed. (The reaction probability of N2O_5 is about 0.02.) In the case of the acidic bisulfate aerosols the major fraction of heterogeneously formed HNO3 resides in the gas phase. For neutral sulfate aerosols a significant fraction of HNO3 is taken up by the condensed phase of the aerosols. This leads to a distinctive growth of the aerosol population during the heterogeneous hydrolysis of N2O_5, which is observable in the number size distribution as well as in IR extinction measurements. The observed partitioning of HNO3 between gas phase and aqueous aerosol phase can be quantitatively understood by a Pitzer based thermodynamic model for salt solutions of high ionic strength. The model calculations and low resolution FTIR spectroscopy demonstrate that protonation of sulfate to bisulfate is the driving force for the uptake of HNO3 in neutral sulfate aerosols.

  12. Primary mesenchyme cell migration requires a chondroitin sulfate/dermatan sulfate proteoglycan. (United States)

    Lane, M C; Solursh, M


    Primary mesenchyme cell migration in the sea urchin embryo is inhibited by sulfate deprivation and exposure to exogenous beta-D-xylosides, two treatments known to disrupt proteoglycan synthesis. We show that in the developing sea urchin, exogenous xyloside affects the synthesis by the primary mesenchyme cells of a very large, cell surface chondroitin sulfate/dermatan sulfate proteoglycan. This proteoglycan is present in a partially purified fraction that restores migratory ability to defective cells in vitro. The integrity of this chondroitin sulfate/dermatan sulfate proteoglycan appears essential for primary mesenchyme cell migration since treatment of actively migrating cells with chondroitinase ABC reversibly inhibited their migration in vitro.

  13. Impact of mineral dust on nitrate, sulfate, and ozone in transpacific Asian pollution plumes

    Directory of Open Access Journals (Sweden)

    T. D. Fairlie


    Full Text Available We use a 3-D global chemical transport model (GEOS-Chem to interpret aircraft observations of nitrate and sulfate partitioning in transpacific dust plumes during the INTEX-B campaign of April–May 2006. The model includes explicit transport of size-resolved mineral dust and its alkalinity, nitrate, and sulfate content. The observations show that particulate nitrate is primarily associated with dust, sulfate is primarily associated with ammonium, and Asian dust remains alkaline across the Pacific. This can be reproduced in the model by using a reactive uptake coefficient for HNO3 on dust (γ(HNO3 ~10−3 much lower than commonly assumed in models and possibly reflecting limitation of uptake by dust dissolution. The model overestimates gas-phase HNO3 by a factor of 2–3, typical of previous model studies; we show that this cannot be corrected by uptake on dust. We find that the fraction of aerosol nitrate on dust in the model increases from ~30% in fresh Asian outflow to 80–90% over the Northeast Pacific, reflecting in part the volatilization of ammonium nitrate and the resulting transfer of nitrate to the dust. Consumption of dust alkalinity by uptake of acid gases in the model is slow relative to the lifetime of dust against deposition, so that dust does not acidify (at least not in the bulk. This limits the potential for dust iron released by acidification to become bio-available upon dust deposition. Observations in INTEX-B show no detectable ozone depletion in Asian dust plumes, consistent with the model. Uptake of HNO3 by dust, suppressing its recycling to NOx, reduces Asian pollution influence on US surface ozone in the model by 10–15% or up to 1 ppb.

  14. Impact of mineral dust on nitrate, sulfate, and ozone in transpacific Asian pollution plumes

    Directory of Open Access Journals (Sweden)

    L. Zhang


    Full Text Available We use a 3-d global chemical transport model (GEOS-Chem to interpret aircraft observations of nitrate and sulfate partitioning in transpacific dust plumes during the INTEX-B campaign of April–May 2006. The model includes explicit transport of size-resolved mineral dust and its alkalinity, nitrate, and sulfate content. The observations show that particulate nitrate is primarily associated with dust, sulfate is primarily associated with ammonium, and Asian dust remains alkaline across the Pacific. This can be reproduced in the model by using a reactive uptake coefficient for HNO3 on dust (γ(HNO3~10−3 much lower than commonly assumed in models and likely reflecting limitation of uptake by dust dissolution. The model overestimates gas-phase HNO3 by a factor of 2–3, typical of previous model studies; we show that this cannot be corrected by uptake on dust. We find that the fraction of aerosol nitrate on dust in the model increases from ~30% in fresh Asian outflow to 80–90% over the Northeast Pacific, reflecting in part the volatilization of ammonium nitrate and the resulting transfer of nitrate to the dust. Consumption of dust alkalinity by uptake of acid gases in the model is slow relative to the lifetime of dust against deposition, so that dust in general does not acidify. This argues against the hypothesis that dust iron released by acidification could become bio-available upon dust deposition. Observations in INTEX-B show no detectable ozone depletion in Asian dust plumes, consistent with the model. Uptake of HNO3 by dust, suppressing its recycling to NOx, reduces Asian pollution influence on US surface ozone in the model by 10–15% or up to 1 ppb.

  15. 40 CFR 418.40 - Applicability; description of the ammonium nitrate subcategory. (United States)


    ... ammonium nitrate subcategory. 418.40 Section 418.40 Protection of Environment ENVIRONMENTAL PROTECTION... Ammonium Nitrate Subcategory § 418.40 Applicability; description of the ammonium nitrate subcategory. The provisions of this subpart are applicable to discharges resulting from the manufacture of ammonium...

  16. 76 FR 39847 - Solid Fertilizer Grade Ammonium Nitrate From the Russian Federation; Final Results of the... (United States)


    ... International Trade Administration Solid Fertilizer Grade Ammonium Nitrate From the Russian Federation; Final... investigation on solid fertilizer grade ammonium nitrate (``ammonium nitrate'') from the Russian Federation...: Solid Fertilizer Grade Ammonium Nitrate From the Russian Federation, 64 FR 45236 (August 19, 1999)....

  17. Metabolic Flexibility of Sulfate Reducing Bacteria

    Directory of Open Access Journals (Sweden)

    Caroline M. Plugge


    Full Text Available Dissimilatory sulfate-reducing prokaryotes (SRB are a very diverse group of anaerobic bacteria that are omnipresent in nature and play an imperative role in the global cycling of carbon and sulfur. In anoxic marine sediments sulfate reduction accounts for up to 50% of the entire organic mineralization in coastal and shelf ecosystems where sulfate diffuses several meters deep into the sediment. As a consequence, SRB would be expected in the sulfate-containing upper sediment layers, whereas methanogenic Archaea would be expected to succeed in the deeper sulfate-depleted layers of the sediment. Where sediments are high in organic matter, sulfate is depleted at shallow sediment depths, and biogenic methane production will occur. In the absence of sulfate, many SRB ferment organic acids and alcohols, producing hydrogen, acetate, and carbon dioxide, and may even rely on hydrogen- and acetate-scavenging methanogens to convert organic compounds to methane. SRB can establish two different life styles, and these can be termed as sulfidogenic and acetogenic, hydrogenogenic metabolism. The advantage of having different metabolic capabilities is that it raises the chance of survival in environments when electron acceptors become depleted. In marine sediments, SRB and methanogens do not compete but rather complement each other in the degradation of organic matter.Also in freshwater ecosystems with sulfate concentrations of only 10-200 μM, sulfate is consumed efficiently within the top several cm of the sediments. Here, many of the δ-Proteobacteria present have the genetic machinery to perform dissimilatory sulfate reduction, yet they have an acetogenic, hydrogenogenic way of life.In this review we evaluate the physiology and metabolic mode of SRB in relation with their environment.

  18. Heterogeneous Uptake of Gaseous N2O5 by Sulfate Aerosols (United States)

    Leu, M.; Kane, S. M.; Caloz, F.


    The heterogeneous uptake of gaseous N2O5 by ammonium sulfate [(NH4)2SO4], ammonium bisulfate [NH4HSO4], and sulfuric acid [H2SO4] aerosols as a function of relative humidity has been investigated at room temperature and atmospheric pressure. Ammonium-containing aerosols were generated by a constant output atomizer and conditioned by passing through a diffusion dryer. Sulfuric acid aerosols were produced by the homogeneous reaction of SO3 and H2O in a borosilicate vessel. Addition of a dry or wet N2 flow controlled the relative humidity (RH) of these aerosol flows. Using a chemical ionization mass spectrometer (CIMS) for N2O5 concentration monitoring and a scanning mobility particle spectrometer (SMPS) for aerosol characterization, reaction probabilities (g) in the range of 0.001 to 0.1 for the uptake of N2O5 were determined as a function of RH. The results are expressed as follows: gamma[(NH4)2SO4] = 2.79 x 10-4 + 1.30 x 10-4 x (RH) -3.43 x 10-6 x (RH)2 + 7.52 x 10-8 x (RH)3, gamma[NH4HSO4] = 2.07 x 10-3 - 1.48 x 10-4 x (RH) + 8.26 x 10-6 x (RH)2, and gamma[H2SO4] = 0.052 - 2.79 x 10-4 x (RH) . We suggest that the water content and phase in the ammonium-containing aerosols control the reactivity of N2O5 while liquid-phase ionic reactions primarily dominate the uptake in sulfuric acid aerosols.

  19. A study of the relationship between anthropogenic sulfate and cloud drop nucleation

    Energy Technology Data Exchange (ETDEWEB)

    Chuang, C. C..; Penner, J. E.


    This document investigates the relationship between anthropogenic sulfate-containing aerosols and the condensationally produced cloud drops. The changes in aerosol size distribution associated with anthropogenic sulfur emissions may increase the number of cloud drops with subsequent influence on cloud albedo and climate. It has been suggested that the increase in CCN in industrial regions might explain why the Northern Hemisphere has not been warming as rapidly as the Southern Hemisphere over the last 50 Years (Wigley, 1989). In reality, the aerosol size distribution is the result of processes working simultaneously and continuously with such sources as sulfur, soot, particulate organic carbon, nitrate, ammonium, etc. Instead of applying a complete aerosol model to investigate the effect of anthropogenic sulfur emissions on the aerosol size distribution, we simply derived the anthropogenic sulfate-containing aerosol distribution by assuming that 75% of the anthropogenic was formed through aqueous-phase oxidation and the remaining 25% condensed onto a Prescribed preexisting particle distribution. Uncertainties may arise from the assumed fraction of sulfate produced by condensation and in cloud oxidation. In addition, new particle formation through homogeneous nucleation of H{sub 2}SO{sub 4}/H{sub 2}O is ignored in this paper.

  20. Comparative biological potency of acidic sulfate aerosols: implications for the interpretation of laboratory and field studies. (United States)

    Schlesinger, R B; Chen, L C


    Biological responses to inhaled acid sulfates result from the deposition of hydrogen ion (H+) on airway surfaces. Thus, effects from sulfuric acid and ammonium bisulfate, the two major ambient species, have been assumed to be the same for a given H+ concentration within the exposure atmosphere, assuming similar respiratory tract deposition patterns. However, recent inhalation studies have indicated that sulfuric acid is disproportionately potent compared to ammonium bisulfate when the H+ content of the exposure atmosphere is considered, suggesting that some factors following inhalation affect the amount of H+ contacting airway surfaces. This study assessed a mechanism potentially underlying this phenomenon, namely, the extent of neutralization by respiratory tract ammonia. This was evaluated using a physical model system designed to mimic transit of these aerosols in the upper respiratory tract of the animal model used in this laboratory, the rabbit. The results suggest that for equal exposure quantities of H+, more acid would be deposited when sulfuric acid is inhaled than when ammonium bisulfate is inhaled. Furthermore, results from a series of in vitro exposures of tracheal epithelial cells to sulfuric acid and ammonium bisulfate aerosols indicated that the biological response is a function of the total mass (ionic) concentration of H+ deliverable to the cells or the total extractable H+ per particle. The results of this study have possible implications for ambient monitoring of particulate-associated strong acidity, suggesting that it may be necessary to specilate such measures into the relative amounts of H+ as sulfuric acid or ammonium bisulfate in order to most accurately relate atmospheric acid levels to observed health effects. In addition, since much of the ambient particulate-associated H+ exists as sulfuric acid/ammonium bisulfate mixtures rather than pure compounds, H(+)-associated health effects from controlled exposure studies of sulfuric acid may

  1. Chlorobenzene formation from fly ash: effect of moisture, chlorine gas, cupric chloride, urea, ammonia and ammonium sulfate

    NARCIS (Netherlands)

    Yan, M.; Qi, Z.F.; Li, X.D.; Chen, T.; Lu, S.Y.; Buekens, A.G.; Olie, K.; Yan, J.H.; Olie, K.


    Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) are formed jointly with numerous products of incomplete combustion during waste incineration. Chlorobenzenes (CBz) are often cited as surrogates or precursors of PCDD/Fs. Experiments were conducted to investigate the effect of some key pa

  2. Characterization of particulate products for aging of ethylbenzene secondary organic aerosol in the presence of ammonium sulfate seed aerosol. (United States)

    Huang, Mingqiang; Zhang, Jiahui; Cai, Shunyou; Liao, Yingmin; Zhao, Weixiong; Hu, Changjin; Gu, Xuejun; Fang, Li; Zhang, Weijun


    Aging of secondary organic aerosol (SOA) particles formed from OH- initiated oxidation of ethylbenzene in the presence of high mass (100-300μg/m(3)) concentrations of (NH4)2SO4 seed aerosol was investigated in a home-made smog chamber in this study. The chemical composition of aged ethylbenzene SOA particles was measured using an aerosol laser time-of-flight mass spectrometer (ALTOFMS) coupled with a Fuzzy C-Means (FCM) clustering algorithm. Experimental results showed that nitrophenol, ethyl-nitrophenol, 2,4-dinitrophenol, methyl glyoxylic acid, 5-ethyl-6-oxo-2,4-hexadienoic acid, 2-ethyl-2,4-hexadiendioic acid, 2,3-dihydroxy-5-ethyl-6-oxo-4-hexenoic acid, 1H-imidazole, hydrated N-glyoxal substituted 1H-imidazole, hydrated glyoxal dimer substituted imidazole, 1H-imidazole-2-carbaldehyde, N-glyoxal substituted hydrated 1H-imidazole-2-carbaldehyde and high-molecular-weight (HMW) components were the predominant products in the aged particles. Compared to the previous aromatic SOA aging studies, imidazole compounds, which can absorb solar radiation effectively, were newly detected in aged ethylbenzene SOA in the presence of high concentrations of (NH4)2SO4 seed aerosol. These findings provide new information for discussing aromatic SOA aging mechanisms.

  3. Quantitative studies on the enzymatic hydrolysis of milk proteins brought about by cardosins precipitated by ammonium sulfate


    Barros,Rui M; Ferreira, Carla A. Ferreira; Silva, Sofia V. Silva; Malcata, F. Xavier


    Hydrolysis of whey proteins may produce peptide mixtures with better functional properties than the original protein mixture, viz. higher solubilites and lower allergenic effects. Cynara cardunculus is a wild plant that possesses (aspartic) proteases in its flower cells; those enzymes exhibit general proteolytic and specific milk clotting activities, which are rather useful in traditional cheesemaking. This study was thus aimed at characterizing the enzymatic action of crude extracts of said ...

  4. Atmospheric Corrosion of Steel A3 Deposited with Ammonium Sulfate and in the Presence of Sulfur Dioxide

    Institute of Scientific and Technical Information of China (English)

    Ye WAN; Chuanwei YAN; Chunan CAO Jun TAN; Jun TAN


    A laboratory study of the atmospheric corrosion of carbon steel deposited with (NH4)2SO4 in the presence of SO2 isreported. The different levels of (NH4)2SO4 (0, 15, 30, 45, 60μ were added on the surface of the samplesbefore the exposure. The corrosion was investigated by a combination of gravimetry, Fourier transform infraredspectroscope and scanning electron microscopy. A detailed knowledge about the corrosion products was acquired,both quantitatively and qualitatively. The results show that the metal loss increased and the increasing tendency ofcorrosion rates slowed down with the increasing exposure time. The phase constituents of the corrosion products aremainly c-FeO(OH), γ-FeO(OH), and δ-FeO(OH).

  5. Optimization of a biological sulfate reduction process

    Energy Technology Data Exchange (ETDEWEB)

    Lebel, A.


    A biological sulfate reduction process is presented. It is intended to treat sulfate wastes by converting them to hydrogen sulfide which can be further oxidized to elemental sulfur. An optimization study of a completely-mixed reactor system was performed. Major operating parameters were determined at the bench-scale level. The study was conducted in batch-culture experiments, using a mixed Desulfovibrio culture from sewage. Kinetic values were extrapolated using the Michaelis-Menten model, which best fitted the experimental data. The iron loading and the sulfate loading significantly affected the growth and metabolism of sulfate reducing bacteria (SRB). A model to determine V/sub m/ from the iron and sulfate loading values was explored. The model is limited by sulfate loading greater than 4.3 g/l, where bacterial growth is inhibited. Iron loading is not anticipated to suppress the bacterial metabolism efficiency since it remained in the linear pattern even at inhibition levels. Studies of the metabolic behavior of SRB, using lactic acid as the carbon source, showed a requirement of 2.7 moles of lactate for each mole of sulfate. This technique and its application to the sulfur recovery process are discussed.

  6. Di-sulfated Keratan Sulfate as a Novel Biomarker for Mucopolysaccharidosis II, IVA, and IVB. (United States)

    Shimada, Tsutomu; Tomatsu, Shunji; Mason, Robert W; Yasuda, Eriko; Mackenzie, William G; Hossain, Jobayer; Shibata, Yuniko; Montaño, Adriana M; Kubaski, Francyne; Giugliani, Roberto; Yamaguchi, Seiji; Suzuki, Yasuyuki; Orii, Kenji E; Fukao, Toshiyuki; Orii, Tadao


    Keratan sulfate (KS) is a storage material in mucopolysaccharidosis IV (MPS IV). However, no detailed analysis has been reported on subclasses of KS: mono-sulfated KS and di-sulfated KS. We established a novel method to distinguish and quantify mono- and di-sulfated KS using liquid chromatography-tandem mass spectrometry and measured both KS levels in various specimens.Di-sulfated KS was dominant in shark cartilage and rat serum, while mono-sulfated KS was dominant in bovine cornea and human serum. Levels of both mono- and di-sulfated KS varied with age in the blood and urine from control subjects and patients with MPS II and IVA. The mean levels of both forms of KS in the plasma/serum from patients with MPS II, IVA, and IVB were elevated compared with that in age-matched controls. Di-sulfated KS provided more significant difference between MPS IVA and the age-matched controls than mono-sulfated KS. The ratio of di-sulfated KS to total KS in plasma/serum increased with age in control subjects and patients with MPS II but was age independent in MPS IVA patients. Consequently, this ratio can discriminate younger MPS IVA patients from controls. Levels of mono- and di-sulfated KS in urine of MPS IVA and IVB patients were all higher than age-matched controls for all ages studied.In conclusion, the level of di-sulfated KS and its ratio to total KS can distinguish control subjects from patients with MPS II, IVA, and IVB, indicating that di-sulfated KS may be a novel biomarker for these disorders.

  7. Using Terrestrial Sulfate Efflorescences as an Analogue of Hydrated Sulfate Formation in Valles Marineris on Mars (United States)

    Smith, P. C.; Szynkiewicz, A.


    Hydrated sulfate minerals provide conclusive evidence that a hydrologic cycle was once active on the surface of Mars. Two classes of hydrated sulfate minerals have been detected by robotic instruments on Mars: monohydrated sulfate minerals comprised of kieserite and gypsum, and various polyhydrated sulfates with Fe-Ca-Na-Mg-rich compositions. These minerals are found in various locations on Mars, including large surface exposures in valley settings of Valles Marineris. However, the sulfate sources and formation mechanisms of these minerals are not yet well understood.Recently, it has been suggested that the sulfate minerals in Valles Marineris might have formed in a manner similar to sulfate efflorescences found in dry environments on Earth. In this study, we use sulfate effloresences from the Rio Puerco Watershed, New Mexico as a terrestrial analogue to assess major factors that might have led to deposition of sulfate minerals in Valles Marineris. In different seasons indicative of dry and wet conditions, we collected field photographs and sediment samples for chemical and stable isotopic analyses (sulfur content, δ34S) to determine major sources of sulfate ions for efflorescences and to assess how the seasonal changes in surface/groundwater activity affect their formation. Preliminary sulfur isotope results suggest that oxidation of bedrock sulfides (0.01-0.05 wt. S %) is a major source of sulfate ion for efflorescences formation because their δ34S varied in negative range (-28 to -20‰) similar to sulfides (average -32‰). Using field photographs collected in Oct 2006, Feb and Nov 2012, May 2013, Mar and Oct 2014, we infer that the highest surface accumulation of sulfate efflorescences in the studied analog site was observed after summer monsoon seasons when more water was available for surface and subsurface transport of solutes from chemical weathering. Conversely, spring snow melt led to enhanced dissolution of sulfate efflorescences.

  8. Sulfated binary and trinary oxide solid superacids

    Institute of Scientific and Technical Information of China (English)

    缪长喜; 华伟明; 陈建民; 高滋


    A series of sulfated binary and trinary oxide solid superacids were prepared, and their catalytic activities for n-butane isomerization at low temperature were measured. The incorporation of different metal oxides into ZrO2 may produce a positive or negative effect on the acid strength and catalytic activity of the solid superacids. Sulfated oxides of Cr-Zr, Fe-Cr-Zr and Fe-V-Zr are 2 - 3 times more active than the reported sulfated Fe-Mn-Zr oxide. The enhancement in the superacidity and catalytic activity of these new solid superacids has been discussed on account of the results of various characteriation techniques.

  9. Analysis of tyrosine-O-sulfation

    DEFF Research Database (Denmark)

    Bundgaard, J.R.; Sen, J.W.; Johnsen, A.H.


    Tyrosine O-sulfation was first described about 50 years ago as a post-translational modification of fibrinogen. In the following 30 years it was considered to be a rare modification affecting only a few proteins and peptides. However, in the beginning of the 1980s tyrosine (Tyr) sulfation was shown...... the presence of radioactively labeled tyrosine. These techniques have been described in detail previously. The aim of this chapter is to present alternative analytical methods of Tyr sulfation than radioisotope incorporation before analysis Udgivelsesdato: 2008...

  10. Chlorate: a reversible inhibitor of proteoglycan sulfation

    Energy Technology Data Exchange (ETDEWEB)

    Humphries, D.E.; Silbert, J.E.


    Bovine aorta endothelial cells were cultured in medium containing (/sup 3/H)glucosamine, (/sup 35/S)sulfate, and various concentrations of chlorate. Cell growth was not affected by 10 mM chlorate, while 30 mM chlorate had a slight inhibitory effect. Chlorate concentrations greater than 10 mM resulted in significant undersulfation of chondroitin. With 30 mM chlorate, sulfation of chondroitin was reduced to 10% and heparan to 35% of controls, but (/sup 3/H)glucosamine incorporation on a per cell basis did not appear to be inhibited. Removal of chlorate from the culture medium of cells resulted in the rapid resumption of sulfation.

  11. Fractionation of bamboo hemicelluloses by graded saturated ammonium sulphate. (United States)

    Guan, Ying; Zhang, Bing; Qi, Xian-Ming; Peng, Feng; Yao, Chun-Li; Sun, Run-Cang


    The hemicelluloses were isolated with 10% KOH at 25°C from dewaxed and delignified bamboo powder. The alkali-soluble hemicelluloses from Sinocalamus affinis were fractionated by ammonium sulphate precipitation method. The bamboo alkali-soluble hemicelluloses yielded seven hemicellulosic fractions obtained at 0, 5, 15, 25, 40, 55, and 70% saturation with ammonium sulphate. It was found that the more branched hemicelluloses were precipitated at higher ammonium sulphate concentrations (55 and 70%), the more linear hemicelluloses were precipitated at lower ammonium sulphate concentrations (0, 5, 15, 25, and 40%). The molecular weights of hemicellulosic fractions become lower from 35,270 (H0) to 18,680 (H70)gmol(-1) with the increasing concentrations of saturated ammonium sulphate from 0 to 70%. Based on the FT-IR, (1)H, (13)C and 2D HSQC NMR studies, the alkali-soluble hemicelluloses were 4-O-methyl-glucuronoarabinoxylans composed of the (1→4)-linked β-d-xylopyranosyl backbone with branches at O-3 of α-L-arabinofuranosyl or at O-2 of 4-O-methyl-α-d-glucuronic acid.

  12. A maritime pine antimicrobial peptide involved in ammonium nutrition. (United States)

    Canales, Javier; Avila, Concepción; Cánovas, Francisco M


    A large family of small cysteine-rich antimicrobial peptides (AMPs) is involved in the innate defence of plants against pathogens. Recently, it has been shown that AMPs may also play important roles in plant growth and development. In previous work, we have identified a gene of the AMP β-barrelin family that was differentially regulated in the roots of maritime pine (Pinus pinaster Ait.) in response to changes in ammonium nutrition. Here, we present the molecular characterization of two AMP genes, PpAMP1 and PpAMP2, showing different molecular structure and physicochemical properties. PpAMP1 and PpAMP2 displayed different expression patterns in maritime pine seedlings and adult trees. Furthermore, our expression analyses indicate that PpAMP1 is the major form of AMP in the tree, and its relative abundance is regulated by ammonium availability. In contrast, PpAMP2 is expressed at much lower levels and it is not regulated by ammonium. To gain new insights into the function of PpAMP1, we over-expressed the recombinant protein in Escherichia coli and demonstrated that PpAMP1 strongly inhibited yeast growth, indicating that it exhibits antimicrobial activity. We have also found that PpAMP1 alters ammonium uptake, suggesting that it is involved in the regulation of ammonium ion flux into pine roots.

  13. Effects of bisphenol A on ammonium assimilation in soybean roots. (United States)

    Sun, Hai; Wang, Li Hong; Zhou, Qing; Huang, Xiao Hua


    Bisphenol A (BPA), which is ubiquitous in the environment, is an example of an endocrine-disrupting compound (EDC). Ammonium assimilation has an important function in plant growth and development. However, insufficient information on the potential effect of BPA on ammonium assimilation in plants is available. In this study, the effects of BPA on ammonium assimilation in roots of soybean seedlings were investigated. During the stress period, 1.5 mg L(-1) of BPA improved glutamine synthetase (GS)/glutamate synthase (GOGAT) cycle and glutamate dehydrogenase (GDH) pathway in ammonium assimilation. The amino acid and the soluble protein contents increased in the soybeans. At 17.2 and 50.0 mg L(-1) of BPA, the GS/GOGAT cycle was inhibited and the GDH pathway was promoted. The amino acid content increased and the soluble protein content decreased. During the recovery period, the GS/GOGAT cycle and the GDH pathway recovered at 1.5 and 17.2 mg L(-1) of BPA but not at 50.0 mg L(-1) of BPA. The amino acid content continuously increased and the soluble protein content decreased compared with those in the control treatment. In summary, BPA treatment could affect the contents of soluble protein and amino acid in the soybean roots by regulating ammonium assimilation.

  14. Removing ammonium from water using modified corncob-biochar. (United States)

    Vu, Thi Mai; Trinh, Van Tuyen; Doan, Dinh Phuong; Van, Huu Tap; Nguyen, Tien Vinh; Vigneswaran, Saravanamuthu; Ngo, Huu Hao


    Ammonium pollution in groundwater and surface water is of major concern in many parts of the world due to the danger it poses to the environment and people's health. This study focuses on the development of a low cost adsorbent, specifically a modified biochar prepared from corncob. Evaluated here is the efficiency of this new material for removing ammonium from synthetic water (ammonium concentration from 10 to 100mg/L). The characteristics of the modified biochar were determined by Brunauer-Emmett-Teller (BET) test, Fourier transform infrared spectroscopy (FTIR) and Scanning electron microscopy (SEM). It was found that ammonium adsorption on modified biochar strongly depended on pH. Adsorption kinetics of NH4(+)-N using modified biochar followed the pseudo-second order kinetic model. Both Langmuir and Sips adsorption isotherm models could simulate well the adsorption behavior of ammonium on modificated biochar. The highest adsorption capacity of 22.6mg NH4(+)-N/g modified biochar was obtained when the biochar was modified by soaking it in HNO3 6M and NaOH 0.3M for 8h and 24h, respectively. The high adsorption capacity of the modified biochar suggested that it is a promising adsorbent for NH4(+)-N remediation from water.

  15. Difficultly Extractable Fixed Ammonium in Some Soils of China

    Institute of Scientific and Technical Information of China (English)



    Ninety-three soil samples and 19 sedimentary rock samples collected from 21 provinces of China were analyzed for their contents of fixed ammonium and total N by Kjeldahl-HF method.Results showed that amount of difficultly extractable fixed ammonium(the fixed ammonium that is not determinable by Kjeldahl procedures commonly used for soils) in soils ranged from 0 to 202 mg kg-1,It was generally more than 50 mg kg-1 in soils in Changji and Turpan districts,Xinjiang,accounting for 3.2%-36.8% with an average of 13.9% of the total N.For some Orthents derived from purple shale and purple sandstone in Sichuan and Hunan provinces and Chao soils derived from secondary loess in Henan Province and Ningxia Autonomous Region it was generally around 30 mg kg-1,accounting for 4%-7% of the total soil N,and for most of the rest of soils studied,with the exception of some subsoils,no or trace difficultly extractable fixed ammonium could be detected.It was sugested that the difficultly extractable fixed ammonium was originated from parent rock,and for slightly weathered soils derived from parent materials rich in this form of N the Kjeldahl method might give underestimation of total soil N.

  16. Quaternary ammonium salt derivatives of allylphenols with peripheral analgesic effect

    Directory of Open Access Journals (Sweden)

    A. B de Oliveira


    Full Text Available Ammonium salt derivatives of natural allylphenols were synthesized with the purpose of obtaining potential peripheral analgesics. These drugs, by virtue of their physicochemical properties, would not be able to cross the blood brain barrier. Their inability to enter into the central nervous system (CNS should prevent several adverse effects observed with classical opiate analgesics (Ferreira et al., 1984. Eugenol (1 O-methyleugenol (5 and safrole (9 were submitted to nitration, reduction and permethylation, leading to the ammonium salts 4, 8 and 12. Another strategy applied to eugenol (1, consisting in its conversion to a glycidic ether (13, opening the epoxide ring with secondary amines and methylation, led to the ammonium salts 16 and 17. All these ammonium salts showed significant peripheral analgesic action, in modified version of the Randall-Sellito test (Ferreira et al. 1978, at non-lethal doses. The ammonium salt 8 showed an activity comparable to that of methylnalorphinium, the prototype of an ideal peripheral analgesic (Ferreira et al., 1984.

  17. Structural basis for the enhanced stability of protein model compounds and peptide backbone unit in ammonium ionic liquids. (United States)

    Vasantha, T; Attri, Pankaj; Venkatesu, Pannuru; Devi, R S Rama


    Protein folding/unfolding is a fascinating study in the presence of cosolvents, which protect/disrupt the native structure of protein, respectively. The structure and stability of proteins and their functional groups may be modulated by the addition of cosolvents. Ionic liquids (ILs) are finding a vast array of applications as novel cosolvents for a wide variety of biochemical processes that include protein folding. Here, the systematic and quantitative apparent transfer free energies (ΔG'(tr)) of protein model compounds from water to ILs through solubility measurements as a function of IL concentration at 25 °C have been exploited to quantify and interpret biomolecular interactions between model compounds of glycine peptides (GPs) with ammonium based ILs. The investigated aqueous systems consist of zwitterionic glycine peptides: glycine (Gly), diglycine (Gly(2)), triglycine (Gly(3)), tetraglycine (Gly(4)), and cyclic glycylglycine (c(GG)) in the presence of six ILs such as diethylammonium acetate (DEAA), diethylammonium hydrogen sulfate (DEAS), triethylammonium acetate (TEAA), triethylammonium hydrogen sulfate (TEAS), triethylammonium dihydrogen phosphate (TEAP), and trimethylammonium acetate (TMAA). We have observed positive values of ΔG'(tr) for GPs from water to ILs, indicating that interactions between ILs and GPs are unfavorable, which leads to stabilization of the structure of model protein compounds. Moreover, our experimental data ΔG'(tr) is used to obtain transfer free energies (Δg'(tr)) of the peptide backbone unit (or glycyl unit) (-CH(2)C═ONH-), which is the most numerous group in globular proteins, from water to IL solutions. To obtain the mechanism events of the ILs' role in enhancing the stability of the model compounds, we have further obtained m-values for GPs from solubility limits. These results explicitly elucidate that all alkyl ammonium ILs act as stabilizers for model compounds through the exclusion of ILs from model compounds of

  18. The biological activity of quaternary ammonium salts (QASs

    Directory of Open Access Journals (Sweden)

    Ewa Obłąk


    Full Text Available Quaternary ammonium salts (QASs, especially those of cationic surfactant character, are applied as antibacterial and antifungal disinfectants. QASs affect lipid-enveloped viruses, including human immunodeficiency virus (HIV and hepatitis B virus (HBV, but not non-enveloped viruses. These compounds are extensively used in domestic (as ingredients of shampoos, hair conditioners, agricultural (as fungicides, pesticides, insecticides, healthcare (as medications, and industrial applications (as biocides, fabric softeners, corrosion inhibitors. The extensive use of quaternary ammonium disinfectants in recent years has led to the development of resistance in microorganisms to these drugs. Thus [i]Staphylococcus[/i] [i]aureus[/i] strains contain the plasmid-carrying genes [i]qacA[/i] and [i]qacB [/i]encoding resistance to quaternary ammonium compounds and acriflavine. The membrane proteins QacA and QacB confer multidrug resistance by exporting the compound by the proton motive force which is generated by the transmembrane electrochemical proton gradient.

  19. [The biological activity of quaternary ammonium salts (QASs)]. (United States)

    Obłak, Ewa; Gamian, Andrzej


    Quaternary ammonium salts (QASs), especially those of cationic surfactant character, are applied as antibacterial and antifungal disinfectants. QASs affect lipid-enveloped viruses, including human immunodeficiency virus (HIV) and hepatitis B virus (HBV), but not non-enveloped viruses. These compounds are extensively used in domestic (as ingredients of shampoos, hair conditioners), agricultural (as fungicides, pesticides, insecticides), healthcare (as medications), and industrial applications (as biocides, fabric softeners, corrosion inhibitors). The extensive use of quaternary ammonium disinfectants in recent years has led to the development of resistance in microorganisms to these drugs. Thus Staphylococcus aureus strains contain the plasmid-carrying genes qacA and qacB encoding resistance to quaternary ammonium compounds and acriflavine. The membrane proteins QacA and QacB confer multidrug resistance by exporting the compound by the proton motive force which is generated by the transmembrane electrochemical proton gradient.

  20. Rocket Solid Propellant Alternative Based on Ammonium Dinitramide

    Directory of Open Access Journals (Sweden)

    Grigore CICAN


    Full Text Available Due to the continuous run for a green environment the current article proposes a new type of solid propellant based on the fairly new synthesized oxidizer, ammonium dinitramide (ADN. Apart of having a higher specific impulse than the worldwide renowned oxidizer, ammonium perchlorate, ADN has the advantage, of leaving behind only nitrogen, oxygen and water after decomposing at high temperatures and therefore totally avoiding the formation of hydrogen chloride fumes. Based on the oxidizer to fuel ratios of the current formulations of the major rocket solid booster (e.g. Space Shuttle’s SRB, Ariane 5’s SRB which comprises mass variations of ammonium perchlorate oxidizer (70-75%, atomized aluminum powder (10-18% and polybutadiene binder (12-20% a new solid propellant was formulated. As previously stated, the new propellant formula and its variations use ADN as oxidizer and erythritol tetranitrate as fuel, keeping the same polybutadiene as binder.

  1. Study on mechanism of isomerization between ammonium thiocyanate and thiourea (United States)

    Zhang, Chao-Zhi; Niu, Meng-Xiao


    Application of ammonium thiocyanate that can be separated from wastewater in coking plant is limited. It may isomerize to thiourea which has widely applied in industry. However, the isomerization yield is low. Moreover, the isomerization temperature is more than 145 °C. In this paper, the isomerization was investigated. The mechanism of the isomerization was supposed based on quantum chemistry calculations. Ammonia was employed as a catalyst to lower isomerization temperature and improved the yield of thiourea in the isomerization reaction. Results of quantum chemical calculation and experiments support the supposed mechanism. The mechanism can be applied in production of thiourea from isomerization of ammonium thiocyanate. The paper suggests a useful way of resourcizing ammonium thiocyanate in wastewater.

  2. Enrichment culture of marine anaerobic ammonium oxidation (anammox) bacteria

    Institute of Scientific and Technical Information of China (English)

    GUAN Yong-jie


    The present study investigates the enrichment of anaerobic ammonium oxidation (anammox) bacteria in the marine environment using sediment samples obtained from the East China Sea and discusses the nitrogen removal efficiency of marine anammox bioreactor. Enrichment of anammox bacteria with simultaneous removal of nitrite and ammonium ions was observed in the Anaerobic Sequencing Batch Reactor under a total nitrogen loading rate of 0.37kg-N m-3day-1. In this study, The nitrogen removal efficiency was up to 80% and the molar-reaction ratio of ammonium, nitrite and nitrate was 1.0:1.22:0.22 which was a little different from a previously reported ratio of 1.0:1.32:0.26 in a freshwater system.

  3. Sulfated cellulose thin films with antithrombin affinity

    Directory of Open Access Journals (Sweden)


    Full Text Available Cellulose thin films were chemically modified by in situ sulfation to produce surfaces with anticoagulant characteristics. Two celluloses differing in their degree of polymerization (DP: CEL I (DP 215–240 and CEL II (DP 1300–1400 were tethered to maleic anhydride copolymer (MA layers and subsequently exposed to SO3•NMe3 solutions at elevated temperature. The impact of the resulting sulfation on the physicochemical properties of the cellulose films was investigated with respect to film thickness, atomic composition, wettability and roughness. The sulfation was optimized to gain a maximal surface concentration of sulfate groups. The scavenging of antithrombin (AT by the surfaces was determined to conclude on their potential anticoagulant properties.

  4. ROE Wet Sulfate Deposition 2009-2011 (United States)

    U.S. Environmental Protection Agency — The raster data represent the amount of wet sulfate deposition in kilograms per hectare from 2009 to 2011. Summary data in this indicator were provided by EPA’s...

  5. Sulfate reduction and methanogenesis at a freshwater

    DEFF Research Database (Denmark)

    Iversen, Vibeke Margrethe Nyvang; Andersen, Martin Søgaard; Jakobsen, Rasmus

    The freshwater-seawater interface was studied in a ~9-m thick anaerobic aquifer located in marine sand and gravel with thin peat lenses. Very limited amounts of iron-oxides are present. Consequently, the dominating redox processes are sulfate reduction and methanogenesis, and the groundwater...... is enriched in dissolved sulfide, methane and bicarbonate. Under normal conditions the seawater-freshwater interface is found at a depth of 4 m at the coastline and reaches the bottom of the aquifer 40 m inland. However, occasional flooding of the area occurs, introducing sulfate to the aquifer. Groundwater...... chemistry was studied in a 120 m transect perpendicular to the coast. Cores were taken for radiotracer rate measurements of sulfate reduction and methanogenesis. In the saline part of the aquifer 35 m inland, sulfate reduction was the dominant process with rates of 0.1-10 mM/year. In the freshwater part 100...

  6. Steady state growth of E. Coli in low ammonium environment (United States)

    Kim, Minsu; Deris, Barret; Zhang, Zhongge; Hwa, Terry


    Ammonium is the preferred nitrogen source for many microorganisms. In medium with low ammonium concentrations, enteric bacteria turn on the nitrogen responsive (ntr) genes to assimilate ammonium. Two proteins in E. coli, Glutamine synthetase (GS) and the Ammonium/methylammonium transporter AmtB play crucial roles in this regard. GS is the major ammonium assimilation enzyme below 1mM of NH4 + . AmtB is an inner membrane protein that transports NH4 + across the cell membrane against a concentration gradient. In order to study ammonium uptake at low NH4 + concentration at neutral pH, we developed a microfluidic flow chamber that maintains a homogenous nutrient environment during the course of exponential cell growth, even at very low concentration of nutrients. Cell growth can be accurately monitored using time-lapse microscopy. We followed steady state growth down to micro-molar range of NH4 + for the wild type and Δ amtB strains. The wild type strain is able to maintain the growth rate from 10mM down to a few uM of NH4 + , while the mutant exhibited reduced growth below ~ 20 ~uM of NH4 + . Simultaneous characterization of the expression levels of GS and AmtB using fluorescence reporters reveals that AmtB is turned on already at 1mM, but contributes to function only below ~ 30 ~uM in the wild-type. Down to ~ 20 ~uM of NH4 + , E.~coli can compensate the loss of AmtB by GS alone.


    Directory of Open Access Journals (Sweden)

    S. PUTRA


    Full Text Available ABSTRACT In line with the regional government programs in sustaining the agricultural ? livestock farming system. An informative talk on enhancing performances and productivity of kacang goat was held at Penatih, Badung reegency on the 20th Dec. 2002. The aim of the community service is to fulfill the farmer?s knowledge and their technical skill in choosing and applying proportional feed stuff, especially using ammonium sulfate mineral as feed supplement on grass-legume based diet. This material which has the capasity to promote rumen microbial growth and their activity in digesting low quality diets. Composing and mixing concentrate diets has also been demonstrated and 4 dietary treatments were tested using 12 goats during a period of 15 days. Ration ( R A contained 97% rice bran + 3% am. Sulfate; RB was 97% rice brand + 3% mineral miz; RC was pollard + 3% am. Sulfate and RD was 97% pollard + 3% mineral mix. Body weight gain were monitored through out the trial period. The result indicated that quality of ration caused improvement of performance and productivity of kacang goats. Body weight gain being increased to 0,067 ? 0,300 kg/head/day for diet A, C, and D, which the highest mean values of 0,217 kg/head/day were obtained for diet D. This situation may due to the present of ammonium sulfate plus zinc (Zn mineral to the legumes basal diet, which can act as metabolic modulator . In general, most of the participants (90% have a very good responses and acceptance for the beneficial information given to them.

  8. Sulfate Resistance of Alkali Activated Pozzolans


    Bondar, Dali


    The consequence of sulfate attack on geopolymer concrete, made from an alkali activated natural pozzolan (AANP) has been studied in this paper. Changes in the compressive strength, expansion and capillary water absorption of specimens have been investigated combined with phases determination by means of X-ray diffraction. At the end of present investigation which was to evaluate the performance of natural alumina silica based geopolymer concrete in sodium and magnesium sulfate solution, the l...

  9. Is there a correlation between structure and anticoagulant action of sulfated galactans and sulfated fucans? (United States)

    Pereira, Mariana S; Melo, Fábio R; Mourão, Paulo A S


    We attempted to identify the specific structural features in sulfated galactans and sulfated fucans that confer anticoagulant activity. For this study we employed a variety of invertebrate polysaccharides with simple structures composed of well-defined units of oligosaccharides. Our results indicate that a 2-O-sulfated, 3-linked alpha-L-galactan, but not a alpha-L-fucan with a similar molecular size, is a potent thrombin inhibitor mediated by antithrombin or heparin cofactor II. The difference between the activities of these two polysaccharides is not very pronounced when factor Xa replaced thrombin. The occurrence of 2,4-di-O-sulfated units is an amplifying motif for 3-linked alpha-fucan-enhanced thrombin inhibition by antithrombin. If we replace antithrombin by heparin cofactor II, then the major structural requirement for the activity becomes single 4-O-sulfated fucose units. The presence of 2-O-sulfated fucose residues always had a deleterious effect on anticoagulant activity. Overall, our results indicate that the structural requirements for interaction of sulfated galactans and sulfated fucans with coagulation cofactors and their target proteases are stereospecific and not merely a consequence of their charge density and sulfate content.

  10. Determination of Ammonium Ion in Lake Water by Voltammetry

    Institute of Scientific and Technical Information of China (English)

    Wu Yun-hua; Fei Jun-jie; Dang Xue-ping; Hu Sheng-shui


    An electroanalytical method for the determination of armonium ion using a platinized platinum electrode is described. Under optimized analytical conditions, the linear range of the calibration graphs for ammonium ion is 3. 0×10(-5)-5.0×10-3 mol·L-1.The Method has been applide to the determination of ammonium ion in lake water samples and recoveries of 100%-103%0 are obtained. The results obtained are found to be in good agreement with spectrophotometric results.

  11. Aerosol isotopic ammonium signatures over the remote Atlantic Ocean (United States)

    Lin, C. T.; Jickells, T. D.; Baker, A. R.; Marca, A.; Johnson, M. T.


    We report aerosol ammonium 15N signatures for samples collected from research cruises on the South Atlantic and Caribbean using a new high sensitivity method. We confirm a pattern of isotopic signals from generally light (δ15N -5 to -10‰), for aerosols with very low (ocean, to generally heavier values (δ15N +5 to +10‰), for aerosols collected in temperate and tropical latitudes and with higher ammonium concentrations (>2 nmol m-3). We discuss whether this reflects a mixing of aerosols from two end-members (polluted continental and remote marine emissions), or isotopic fractionation during aerosol transport.

  12. Mutagenic activity of quaternary ammonium salt derivatives of carbohydrates (United States)

    Sikora, Karol; Woziwodzka, Anna; Piosik, Jacek; Podgórska, Beata


    Summary This paper presents a study on a series of quaternary ammonium salt (QAS) derivatives of glucopyranosides with an elongated hydrophobic hydrocarbon chain. The new N-[6-(β-D-glucopyranosyloxy)hexyl]ammonium bromides and their O-acetyl derivatives were analyzed via 1H and 13C NMR spectroscopy. The mutagenic activity of the newly synthesized QAS was investigated using two different techniques: The Vibrio harveyi luminescence assay and the Ames test. The obtained results support previous findings contesting QAS safety and indicate that QAS, specifically pyridinium derivatives, might be mutagenic. PMID:27559394

  13. Hormonal control of sulfate uptake and assimilation. (United States)

    Koprivova, Anna; Kopriva, Stanislav


    Plant hormones have a plethora of functions in control of plant development, stress response, and primary metabolism, including nutrient homeostasis. In the plant nutrition, the interplay of hormones with responses to nitrate and phosphate deficiency is well described, but relatively little is known about the interaction between phytohormones and regulation of sulfur metabolism. As for other nutrients, sulfate deficiency results in modulation of root architecture, where hormones are expected to play an important role. Accordingly, sulfate deficiency induces genes involved in metabolism of tryptophane and auxin. Also jasmonate biosynthesis is induced, pointing to the need of increase the defense capabilities of the plants when sulfur is limiting. However, hormones affect also sulfate uptake and assimilation. The pathway is coordinately induced by jasmonate and the key enzyme, adenosine 5'-phosphosulfate reductase, is additionally regulated by ethylene, abscisic acid, nitric oxid, and other phytohormones. Perhaps the most intriguing link between hormones and sulfate assimilation is the fact that the main regulator of the response to sulfate starvation, SULFATE LIMITATION1 (SLIM1) belongs to the family of ethylene related transcription factors. We will review the current knowledge of interplay between phytohormones and control of sulfur metabolism and discuss the main open questions.

  14. Preparation of Agarose Sulfate and Its Antithrombogenicity

    Institute of Scientific and Technical Information of China (English)

    JIE Youping; ZHANG Lingmin; CHEN Peng; MAO Xuan; TANG Shunqing


    As one of the seaweed polysaccharide,agarose has received much attention because of its biocompatibility.However,its application in biomedical field was limited with its biological inertia.Modification with some functional groups is needed to obtain agarose derivatives with biological activity and expand its applications.Consequently,agarose was sulfated with chlorosulfonic acid-pyridine with formamide as dispersing agent.The orthogonal test result showed that the optimal reaction condition was the reaction time being 4 h,the reaction temperature 65 ℃,and the ratio of chlorosulfonic acid to agarose 1-4(mL/g).Two kinds of the insoluble agarose sulfate (below 37 ℃) were synthesized with degree of substitution (DS) being 0.17 and 0.43 respectively.Infrared spectroscopy (IR) and 13C nuclear magnetic resonance (13C-NMR) spectroscopy results proved that C3-6 in agarose was sulfated.Their hydrophobic property and BSA adsorption capacity rose with increasing DS,while the adsorption of Hb was reduced.The anti-clotting properties of agarose sulfate were significantly improved,and agarose sulfate could protect red blood cells from deformation after adsorption of BSA.These findings demonstrate that the cold-water insoluble agarose sulfate has a promise for applications as heparin-like material in anticoagulation or endothelial regeneration scaffold.

  15. Structure of a rat hepatoma heparan sulfate

    Energy Technology Data Exchange (ETDEWEB)

    Fedarko, N.S.; Ishihara, M.; Conrad, H.E.


    Previous studies showed that as monolayer cultures of a rat hepatocyte cell line passed from log growth to confluency there was an increase in sulfation of heparan sulfate (HS) and the accumulation of a unique species of HS with a high content of sulfated GlcA residues in the nucleus. The present study compares the HS metabolism of a rat (Morris) hepatoma line. Cells were labeled with /sup 35/SO/sub 4//sup 2 -/ and the structure and distribution of (/sup 35/SO/sub 4/)HS from the culture medium (CM), the pericellular matrix (Ma), the nucleus (NUC), the outer nuclear membrane (NM), and the remaining cytoplasmic (CP) pool was measured as nitrous acid-susceptible material. The amount of label incorporated into each pool was 1/10 that observed in the hepatocyte line. The HS proteglycan and the free HS chains from the hepatoma showed size distributions similar to those found for the hepatocytes, but a lower average charge density. In the HS from the CM, Ma, and CP pools 56% of glucosamine residues were sulfated; in that from the NM and NUC pools 46% were sulfated. HONO treatment gave mono- and disulfated disaccharides in a ratio of 1.5:1 for all five cellular pools, but showed that the HS from the NUC pool did not contain high levels of sulfated GlcA residues.

  16. Adsorption of ammonium dinitramide (ADN) from aqueous solutions. 1. Adsorption on powdered activated charcoal. (United States)

    Santhosh, G; Venkatachalam, S; Ninan, K N; Sadhana, R; Alwan, S; Abarna, V; Joseph, M A


    Investigations on the adsorption of ammonium dinitramide (NH(4)N(NO(2))(2)) (ADN) from aqueous solutions on powdered activated charcoal (PAC) were carried out in order to find out an effective and easier method of separating ADN from aqueous solutions. The effectiveness of PAC in the selective adsorption of ADN from aqueous solutions of ADN (ADN-F) and ADN in presence of sulfate (SO(4)(2-)) and nitrate (NO(3)(-)) ions (ADN-PS) was examined and compared using batch and column methods. The adsorption process follows both Langmuir and Freundlich adsorption isotherms and the isotherm parameters for the models were determined. The observed data favor the formation of monolayer adsorption. The adsorption capacities were found to be 63.3, 119, 105.3 and 82 mg of ADN per g of PAC for ADN-F (batch), ADN-PS (batch), ADN-F (column) and ADN-PS (column), respectively. Break-through curves for ADN-F and ADN-PS were obtained for the optimization of separation of ADN from aqueous solutions. Elution curves were generated for the desorption of ADN from PAC using hot water as eluent.

  17. Determination of kjeldahl nitrogen in fertilizers by AOAC official methods 978.02: effect of copper sulfate as a catalyst. (United States)

    Abrams, Dean; Metcalf, David; Hojjatie, Michael


    In AOAC Official Method 955.04, Nitrogen (Total) in Fertilizers, Kjeldahl Method, fertilizer materials are analyzed using mercuric oxide or metallic mercury HgO or Hg) as a catalyst. AOAC Official Methods 970.02, Nitrogen (Total) in Fertilizers is a comprehensive total nitrogen (including nitrate nitrogen) method adding chromium metal. AOAC Official Method 978.02, Nitrogen (Total) in Fertilizers is a modified comprehensive nitrogen method used to measure total nitrogen in fertilizers with two types of catalysts. In this method, either copper sulfate or chromium metal is added to analyze for total Kjeldahl nitrogen. In this study, the part of AOAC Official Method 978.02 that is for nitrate-free fertilizer products was modified. The objective was to examine the necessity of copper sulfate as a catalyst for the nitrate-free fertilizer products. Copper salts are not environmentally friendly and are considered pollutants. Products such as ammonium sulfate, diammonium phosphate, monoammonium phosphate, urea-containing fertilizers such as isobutylene diurea (IBDU), and urea-triazone fertilizer solutions were examined. The first part of the study was to measure Kjeldahl nitrogen as recommended by AOAC Official Method 978.02. The second part of the study was to exclude the addition of copper sulfate from AOAC Official Method 978.02 to examine the necessity of copper sulfate as a catalyst in nitrate-free fertilizers, which was the primary objective. Our findings indicate that copper sulfate can be eliminated from the method with no significant difference in the results for the nitrogen content of the fertilizer products.

  18. Comparative potency of inhaled acidic sulfates: speciation and the role of hydrogen ion. (United States)

    Schlesinger, R B; Chen, L C; Finkelstein, I; Zelikoff, J T


    Inhaled acidic sulfate aerosols affect various aspects of lung function, presumably by delivery of hydrogen ion (H+) to target sites. Recent evidence suggests that the relationship between response and H+ content of the exposure atmosphere may depend upon the specific sulfate species with which the H+ is associated. This study examined comparatively the effects of exposure to the two main ambient acidic sulfates, sulfuric acid (H2SO4) and ammonium bisulfate (NH4HSO4), using the phagocytic activity of alveolar macrophages as the endpoint. Rabbits were exposed to 250-2000 micrograms/m3 H2SO4 (as SO4(-2)) and 500-4000 micrograms/m3 NH4HSO4 (as SO4(-2)) for 1 hr/day for 5 days; bronchopulmonary lavage was then performed for recovery of free lung cells. Phagocytosis, measured by uptake of opsonized latex spheres in vitro, was altered by exposure to H2SO4 at concentrations greater than or equal to 500 micrograms/m3 and to NH4HSO4 at greater than or equal to 2000 micrograms/m3. Assessment of results in terms of the calculated hydrogen ion concentration in the exposure atmosphere showed that identical levels of H+ produced different degrees of response depending upon whether exposure was to H2SO4 or NH4HSO4. On the other hand, macrophages incubated in acidic environments in vitro responded similarly regardless of whether H2SO4 or NH4HSO4 was used to adjust the pH. Possible reasons for the difference in response observed in vivo and in vitro are discussed. Speciation of ambient acidic sulfate aerosols may be needed in atmospheric monitoring so as to assess the presence of H+ posing the greatest biologic hazard following inhalation exposure.

  19. Sulfated polysaccharides and cell differentiation in the sea urchin embryo. (United States)

    Løvtrup-Rein, H; Løvtrup, S


    The synthesis of sulfated polysaccharides during the embryonic development of Paracentrotus lividus has been investigated by incorporation of radioactive sulfate, glucose, glucosamine and fucose. The following substances become labelled: fucan sulfate (approximately 60%), heparan sulfate (approximately 20%) and dermatan sulfate (approximately 20%), and possibly a very slight amount of chondroitin sulfate. In animalized and vegetalized embryos, the rate of incorporation is significantly reduced, and furthermore dermatan sulfate is almost absent in animalized embryos. It is concluded that this substance is associated with the differentiation of vegetative cells, possibly the mesenchyme cells.

  20. Diversity of sulfur isotope fractionations by sulfate-reducing prokaryotes

    DEFF Research Database (Denmark)

    Detmers, Jan; Brüchert, Volker; Habicht, K S;


    Batch culture experiments were performed with 32 different sulfate-reducing prokaryotes to explore the diversity in sulfur isotope fractionation during dissimilatory sulfate reduction by pure cultures. The selected strains reflect the phylogenetic and physiologic diversity of presently known....... Sulfate reducers that oxidized the carbon source completely to CO2 showed greater fractionations than sulfate reducers that released acetate as the final product of carbon oxidation. Different metabolic pathways and variable regulation of sulfate transport across the cell membrane all potentially affect...

  1. Aqueous Media Oxidation of Alcohols with Ammonium Persulfate

    Institute of Scientific and Technical Information of China (English)

    IMANZADEH, Gholam Hassan; ZAMANLOO, Mohammad R.; MANSOORI, Yaghoob; KHODAYARI, Ali


    Oxidation of series of various primary and secondary alcohols to corresponding carbonyl compounds with ammonium persulfate in aqueous media was described. No over oxidation of primary alcohols to carboxylic acids and secondary alcohols to esters was observed. Under such conditions benzoin was converted to benzoic acid.

  2. New synthetic method and properties of ammonium dinitramide (ADN)

    Energy Technology Data Exchange (ETDEWEB)

    Hatano, H.; Onda, T.; Shi Ino, K.; Kiname, S.I. [Technical Center, Hosoya Kako, Osawa (Japan); Miyazaki, S.; Suzuki, S. [Research et Development Center, Nissan Motor Co, Saitama (Japan)


    Ammonium dinitramide (ADN) is one of the energetic materials, its hazard, however, has never been presented yet. In this paper, new synthetic method of ADN and its properties are contained. It has been found out that ADN has little hazard and is a safe energetic compound. (authors) 4 refs.

  3. 75 FR 14082 - Ammonium Salts of Fatty Acids (C8 (United States)


    ... diet of humans, animals, and plants and currently have Food and Drug Administration and EPA approved.../kg/day (6 times the limit dose of 1,000 mg/kg/day) on days 2 to 13 of pregnancy and musculo-skeletal... plants. Ammonium salts of fatty acid are not likely to persist in the environment and are expected to...

  4. Increase of water resistance of ammonium nitrate explosives

    Directory of Open Access Journals (Sweden)

    Zulkhair Mansurov


    Full Text Available Developed a method of kapsulating of ammonium nitrate with liquid paraffin increase finding explosives in water for 60 minutes. Placing explosives in the plastic shell, the explosive was, as in standing or running water during the day. When conducting field tests failures were absent.

  5. Characterization of ammonium polyuranate powders from a continuous precipitator

    Energy Technology Data Exchange (ETDEWEB)

    Oolman, T.


    Ammonium polyuranate powders produced in a continuous, well-mixed precipitator were characterized by means of electron microscopy. The powders were qualitatively analyzed with the scanning electron microscope and the elementary crystallites were quantivatively analyzed with the transmission electron microscope. The results were fit to a kinetic theory of continuous precipitation. A phase analysis was also preformed by x-ray powder diffraction.

  6. Synthetic receptors for ammonium ions using dynamic combinatorial chemistry

    NARCIS (Netherlands)

    Hamieh, Saleh


    The general topic of this dissertation is the development of synthetic receptors for organic ammonium ions in near physiological conditions using disulfide dynamic combinatorial chemistry (DCC). Chapter 1 explains the importance of this development and the associated difficulties when using the conv

  7. Carboxylates and the uptake of ammonium by excised maize roots

    NARCIS (Netherlands)

    Breteler, H.


    The effect of carboxylates (organic acid anions) on NH 4 uptake was studied by changing the carboxylate level of roots prior to uptake experi ments. Succinate was the most effective stimulator of ammonium uptake. The oxocarboxylates (α-oxoglutarate, oxaloacetate and

  8. Treating leachate mixture with anaerobic ammonium oxidation technology

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hong-guo; ZHOU Shao-qi


    Large amounts of ammonium and a low content of biodegradable chemical oxygen demand(COD) are contained in leachate from aged landfills, together with the effluent containing high concentration of nitric nitrogen after biochemical treatment.Treatment effect of anaerobic ammonium oxidation (anammox) process on the mixture of the leachate and its biochemical effluent was investigated. The results show that the average removal efficiencies of ammonium, nitric nitrogen and total nitrogen are 87.51%,74.95% and 79.59%, respectively, corresponding to the average ratio of removed nitric nitrogen to ammonium, i.e. 1.14 during the steady phase of anammox activity. The mean removal efficiency of COD is only 24.01% during the experimental period. The demand of total phosphorous for the anammox process is unobvious. Especially, the alkalinity and pH value of the effluent are close to those of the influent during the steady phase of anammox activity. In addition, it is demonstrated that the status of the anammox bioreactor can be indicated by the alkalinity and pH value during the course of the experiment. The anammox bioreactor has shown potential for nitrogen removal in the leachate mixture. However, COD and total phosphorous in the leachate mixture need further treatment for removal efficiencies of COD and total phosphorous are not good in the anammox bioreactor.

  9. Growth features of ammonium hydrogen -tartrate single crystals

    Indian Academy of Sciences (India)

    G Sajeevkumar; R Raveendran; B S Remadevi; Alexander Varghese Vaidyan


    Ammonium hydrogen -tartrate (-AHT) single crystals were grown in silica gel. The growth features of these crystals with variation of parameters like specific gravity of the gel, gel pH, acid concentrations, concentration of the feed solution and gel age were studied in detail.

  10. Profiling the origin of ammonium nitrate: proof-of-principle

    NARCIS (Netherlands)

    Carol-Visser, J.; Farmache, M.A.; Heijden, A.E.D.M. van der


    In many Improvised Explosive Devices (IEDs) the main charge consists of ammonium nitrate (AN). For forensic reasons, screening for the origin of AN is of importance. By assessing specifi c characteristics, diff erent AN batches can be profi led, in this way providing extra information which could le

  11. Sulfated polysaccharides and immune response: promoter or inhibitor? (United States)

    Chen, D; Wu, X Z; Wen, Z Y


    Sulfated polysaccharides, which frequently connect to core protein, are expressed not only on cell surface but also throughout the extracellular matrix. Besides providing structural integrity of cells, sulfated polysaccharides interact with a variety of sulfated polysaccharides-binding proteins, such as growth factors, cytokines, chemokines and proteases. Sulfated polysaccharides play two-edged roles, inhibitor and promoter, in immune response. Some sulfated polysaccharides act as the immunosuppressor by blocking inflammatory signal transduction induced by proinflammatory cytokines, suppressing the activation of complement and inhibiting the process that leukocytes adhere to and pass through endothelium. On the contrary, the interaction between immune cells and sulfated polysaccharides produced by bacteria, endothelial cells and immune cells initiate the occurrence of immune response. It promotes the processes of recognizing and arresting antigen, migrating transendothelium, moving into and out of immune organ and enhancing the proliferation of lymphocyte. The structure of sulfated polysaccharides, such as molecular weight and sulfated sites heterogeneity, especially the degree of disaccharide sulfation, position of the sulfate moiety and organization of sulfated domains, may play critical role in their controversial effects. As a consequence, the interaction between sulfated polysaccharides and sulfated polysaccharide-binding proteins may be changed by modifying the structure of sulfated polysaccharides chains. The administration of drug targeting sulfated polysaccharide-protein interaction may be useful in treating inflammatory related diseases.

  12. On the roles and regulation of chondroitin sulfate and heparan sulfate in zebrafish pharyngeal cartilage morphogenesis

    DEFF Research Database (Denmark)

    Holmborn, Katarina; Habicher, Judith; Kasza, Zsolt;


    The present study addresses the roles of heparan sulfate (HS) proteoglycans and chondroitin sulfate (CS) proteoglycans in the development of zebrafish pharyngeal cartilage structures. uxs1 and b3gat3 mutants, predicted to have impaired biosynthesis of both HS and CS because of defective formation...

  13. Determination of nitrogen content in milk by the Kjeldahl method using copper sulfate: interlaboratory study. (United States)

    Grappin, R; Horwitz, W


    Copper sulfate was substituted for mercury as the catalyst in the International Dairy Federation (IDF) Standard 20A:1986 method for the determination of nitrogen content in milk. The substitution was supported by results obtained in an interlaboratory study by 24 laboratories in 12 countries. Each laboratory analyzed 12 test samples of milk as blind duplicates in a double split level design with high, medium, and low nitrogen concentrations. The method protocol requires the concurrent analyses of an ammonium salt solution and a tryptophan solution as internal quality control standards with a minimum nitrogen recovery between 99 and 100% for the former and at least 98% for the latter. The repeatability and reproducibility relative standard deviations are 0.5 and 1%, respectively, for the range 0.35-0.70 g N/100 g. The performance of the laboratories that did not meet the required quality control specifications was clearly poorer than that of those that did meet the specifications.

  14. Maximizing ammonium nitrogen removal from solution using different zeolites. (United States)

    Penn, Chad J; Warren, Jason G; Smith, Savannah


    Zeolite minerals are ideal for removing ammonium nitrogen (NH4(+)-N) from animal wastes, leachates, and industrial effluents. The objectives of this study were to compare NH4+ removal and kinetics among several commercially available zeolites under various conditions and determine if calorimetry could provide information regarding kinetics of NH4+ removal. Ammonium sorption onto potassium (K) saturated zeolites was compared using synthetic vs. natural swine effluent and with either traditional batch-shaken system or a "tea bag" approach in which zeolites were contained in a mesh sack and suspended in a solution of swine effluent. Ammonium sorption was measured at four retention times using a flow-through system, and the resulting heat response was measured using isothermal calorimetry. Ammonium removal was not significantly different in synthetic vs. natural swine effluent. Ammonium removal was lower in batch-stirred compared to batch-shaken systems, suggesting that diffusion between particles was rate-limiting in the former system. Flow-through cells possessing contact times > 100 s displayed greater NH4+ sorption than batch systems, suggesting that maintaining high NH4+ concentration in solution, removal of exchange products, and sufficient reaction time are critical to maximizing NH4+ removal by zeolites. Within 100 s after NH4+ addition, endothermic heat responses indicated that NH4(+)-K+ exchange had peaked; this was followed by significant heat rate reduction for 50 min. This confirmed findings of an initial fast NH4(+)-K+ exchange followed by a slower one and suggests the 100-s period of rapid reaction is an indicator of the minimum flow through retention time required to optimize NH4+ sorption to zeolites used in this study.

  15. Recycle use of magnesium ammonium phosphate to remove ammonium nitrogen from rare-earth wastewater. (United States)

    Huang, H M; Xiao, X M; Yan, B


    This paper presents a recycle MAP process (magnesium ammonium phosphate) to remove NH4-N from a typical rare-earth wastewater. The optimum conditions for the MAP precipitation and recycle use of the MAP with a newly-designed process were investigated in laboratory. The results showed that the pH value and dosages of P (phosphate) and Mg reagents have a significant influence on NH4-N removal, with a maximum removal efficiency of 99.4% at the conditions of pH=9 and Mg:N:P molar ratio=1.2:1:1.2. In the process of recycle use of the MAP, adding some HCl to dissolve MAP decomposition residues could effectively enhance NH4-N removal. The NH4-N removal efficiency reached 99.6% by adding an HCl amount of H+:OH- molar ratio=0.8 into the reused MAP decomposition residues, whereas the NH4-N removal efficiency without addition of HCl was only 96.4%. Moreover, the residual PO4-P from the end of reaction was recovered and the optimum recovery efficiency was achieved at a Mg:P molar ratio=6 and pH=10. Under these optimum conditions, the residual NH4-N and PO4-P concentrations in the treated wastewater, through 6 times of the recycling, were less than 15 mg/L and 1 mg/L, respectively. On the basis of this, an economic evaluation of the recycling MAP was made, and this recycle process could save 48.6% cost used in the chemicals for treating per cubic meter of the rare-earth wastewater, compared to the conventional MAP process.

  16. Characterization of lighted upflow anaerobic sludge blanket (LUASB) method under sulfate-rich conditions. (United States)

    Sawayama, S; Tsukahara, K; Yagishita, T; Hanada, S


    Growth of phototrophic bacteria was induced from granules in a lighted upflow anaerobic sludge blanket (LUASB) reactor supplied with an organic-acid-based medium containing 141.7 mg S.l(-1) of SO4(2-) under light conditions (100 microE.m(-2).s(-1)). We investigated the population dynamics of phototrophic bacteria in the LUASB reactor and the performance of the LUASB reactor for wastewater treatment and poly-beta-hydroxybutyrate (PHB) production under anaerobic light and sulfate-rich conditions. In vivo absorption spectra and a colony count suggested that populations of Rhodopseudomonas palustris and Blastochloris sulfoviridis in the LUASB reactor supplied with a medium containing 574.4 mg S.l(-1) of SO4(2-) under light conditions were lower than those supplied with a medium containing 1.0 or 141.7 mg S.l(-1) of SO4(2-) under parallel conditions. Removal efficiencies of ammonium and phosphate in the LUASB reactor supplied with the medium containing 141.7 mg S.l(-1) of SO4(2-) under light conditions were higher than those under parallel conditions but without illumination. The difference in the results of runs under light or dark conditions suggested that the ammonium and phosphate ion removal efficiencies were improved by increasing the amount of phototrophic bacterial biomass in the LUASB reactor under sulfate-rich conditions. The average PHB production rates of the bacterial cells recovered from the effluent of the LUASB reactor supplied with a medium containing 141.7, 283.5 or 574.4 mg S.l(-1) of SO4(2-) were 1.0-2.9 mg.l(-1)-reactor.d(-1) and the average PHB content based on the dry bacterial biomass was 1.4-3.6%.

  17. Electrochemical oxidation of quaternary ammonium electrolytes : Unexpected side reactions in organic electrochemistry

    NARCIS (Netherlands)

    Nouri Nigjeh, Eslam; de Vries, Marcel; Bruins, Andries P.; Bischoff, Rainer; Permentier, Hjalmar P.


    Quaternary ammonium salts are among the most widely used electrolytes in organic electrochemistry, but there is little known about their unwanted side oxidation reactions. We have, therefore, studied the constant potential oxidation products of quaternary ammonium electrolytes using mass spectrometr

  18. Antibacterial activity of reactive quaternary ammonium compounds in solution and in nonleachable coatings

    NARCIS (Netherlands)

    Gozzelino, G.; Romero Tobar, D.E.; Chaitiemwong, N.; Hazeleger, W.C.; Beumer, R.R.


    Antibacterial polymers suitable for coating applications without leaching of the biocidal component have been obtained by UV copolymerization of acrylic resins with acrylic monomers containing quaternary ammonium moieties. Suitable reactive biocides, based on quaternary ammonium monomers (QAMs), end

  19. Heparin-like properties of sulfated alginates with defined sequences and sulfation degrees. (United States)

    Arlov, Øystein; Aachmann, Finn Lillelund; Sundan, Anders; Espevik, Terje; Skjåk-Bræk, Gudmund


    Sulfated glycosaminoglycans have a vast range of protein interactions relevant to the development of new biomaterials and pharmaceuticals, but their characterization and application is complicated mainly due to a high structural variability and the relative difficulty to isolate large quantities of structurally homogeneous samples. Functional and versatile analogues of heparin/heparan sulfate can potentially be created from sulfated alginates, which offer structure customizability through targeted enzymatic epimerization and precise tuning of the sulfation degree. Alginates are linear polysaccharides consisting of β-D-mannuronic acid (M) and α-L-guluronic acid (G), derived from brown algae and certain bacteria. The M/G ratio and distribution of blocks are critical parameters for the physical properties of alginates and can be modified in vitro using mannuronic-C5-epimerases to introduce sequence patterns not found in nature. Alginates with homogeneous sequences (poly-M, poly-MG, and poly-G) and similar molecular weights were chemically sulfated and structurally characterized by the use of NMR and elemental analysis. These sulfated alginates were shown to bind and displace HGF from the surface of myeloma cells in a manner similar to heparin. We observed dependence on the sulfation degree (DS) as well as variation in efficacy based on the alginate monosaccharide sequence, relating to relative flexibility and charge density in the polysaccharide chains. Co-incubation with human plasma showed complement compatibility of the alginates and lowering of soluble terminal complement complex levels by sulfated alginates. The sulfated polyalternating (poly-MG) alginate proved to be the most reproducible in terms of precise sulfation degrees and showed the greatest relative degree of complement inhibition and HGF interaction, maintaining high activity at low DS values.

  20. Evolution of strategies to achieve baseline separation of ten anionic, water-soluble sulfated estrogens via achiral packed column supercritical fluid chromatography. (United States)

    Patel, M A; Hardink, M A; Wrisely, L; Riley, F W; Hudalla, C J; Ashraf-Khorassani, M; Taylor, L T


    Near baseline separation of ten sulfated sodium salts of various structurally related estrogens employing a variety of bonded stationary phase packed columns was obtained using a conventional supercritical fluid chromatograph coupled with UV detection. Critical pairs 2/3 (8,9-dehydroestrone/17β-dihydroequilin) and 6/7 (17α-estradiol or 17α-dihydroequilin/estrone), however, failed to baseline separate. In all preliminary separations, 10mM ammonium acetate and variable percentages of H2O were initially used as co-additives in conjunction with methanol as a modifier. Different modifier programs and temperatures were employed to optimize the separation in a timely manner. A 2-ethylpyridine column provided the best separation compared to bare silica, diol, and cyano-based bonded phase columns. The employment of both salt and water as additives to the methanol-modified CO2 mobile phase suggested a mixed mode separation mechanism involving both ion pairing of each anionic sulfated estrogen with ammonium ion and hydrophilic interaction facilitated by partitioning of analyte between the aqueous solvated stationary phase and the aqueous component of the mobile phase. Upon more extensive study with either iso-propylamine or formic acid-ammonium formate buffer, the critical anionic pairs were 95% baseline resolved.

  1. Nitrification and N2O production processes in soil incubations after ammonium fertilizer application at high concentrations (United States)

    Deppe, Marianna; Well, Reinhard; Giesemann, Anette; Flessa, Heinz


    High concentrations of ammonium as they occur, e.g., after point-injection of ammonium fertilizer solution according to the CULTAN fertilization technique may retard nitrification. Potential advantages in comparison to conventional fertilization include a higher N efficiency of crops, reduced nitrate leaching, and lower N2O and N2 emissions. Dynamics of nitrification due to plant uptake and dilution processes, leading to decreasing ammonium concentrations in fertilizer depots, has only poorly been studied before. Furthermore, there is little information about the relative contribution of different N2O production processes under these conditions. To elucidate the process dynamics a laboratory incubation study was conducted. After fertilization with ammonium sulfate at 5 levels (from 0 to 5000 mg NH4+-N kg-1; 20mg NO3--N kg-1 each), sandy loam soil was incubated in dynamic soil microcosms for 21 days. N2O, CH4 and CO2 fluxes as well as isotope signatures of N2O and, at three dates, NO3- and NH4+ were measured. To identify N2O production processes, acetylene inhibition (0.01 vol.%), 15N tracer approaches, and isotopomer data (15N site preference and δ18O) were used. N2O emissions were highest at 450mg NH4+-N kg-1 and declined with further increasing concentrations. At 5000 mg NH4+-N kg-1 nitrification was completely inhibited. However, approximately 90% of N2O production was inhibited by acetylene application, and there was no change in the relative contribution of nitrification and denitrification to N2O production with N level. Applying the non-equilibrium technique to our 15N tracer data revealed heterogeneous distribution of denitrification in soil, with at least two distinct NO3- pools, and spatial separation of NO3- formation and consumption. In comparison with the acetylene inhibition and 15N tracer approaches the results of the isotopomer approach were reasonable and indicated substantial contribution of nitrifier-denitrification (10-40%) to total N2O

  2. p-Cresyl sulfate and indoxyl sulfate in pediatric patients on chronic dialysis

    Directory of Open Access Journals (Sweden)

    Hye Sun Hyun


    Full Text Available &lt;b&gt;Purpose:&lt;/b&gt; Indoxyl sulfate and p- cresyl sulfate are important protein-bound uremic retention solutes whose levels can be partially reduced by renal replacement therapy. These solutes originate from intestinal bacterial protein fermentation and are associated with cardiovascular outcomes and chronic kidney disease progression. The aims of this study were to investigate the levels of indoxyl sulfate and p- cresyl sulfate as well as the effect of probiotics on reducing the levels of uremic toxins in pediatric patients on dialysis. &lt;b&gt;Methods:&lt;/b&gt; We enrolled 20 pediatric patients undergoing chronic dialysis; 16 patients completed the study. The patients underwent a 12-week regimen of VSL#3, a high-concentration probiotic preparation, and the serum levels of indoxyl sulfate and p- cresyl sulfate were measured before treatment and at 4, 8, and 12 weeks after the regimen by using fluorescence liquid chromatography. To assess the normal range of indoxyl sulfate and p- cresyl sulfate we enrolled the 16 children with normal glomerular filtration rate who had visited an outpatient clinic for asymptomatic microscopic hematuria that had been detected by a school screening in August 2011. &lt;b&gt;Results:&lt;/b&gt; The baseline serum levels of indoxyl sulfate and p- cresyl sulfate in the patients on chronic dialysis were significantly higher than those in the children with microscopic hematuria. The baseline serum levels of p- cresyl sulfate in the peritoneal dialysis group were significantly higher than those in the hemodialysis group. There were no significant changes in the levels of these uremic solutes after 12-week VSL#3 treatment in the patients on chronic dialysis. &lt;b&gt;Conclusion:&lt;/b&gt; The levels of the uremic toxins p- cresyl sulfate and indoxyl sulfate are highly elevated in pediatric patients on dialysis, but there was no significant effect by

  3. Long-term atmospheric deposition of nitrogen, phosphorus and sulfate in a large oligotrophic lake. (United States)

    Ellis, Bonnie K; Craft, James A; Stanford, Jack A


    We documented significantly increasing trends in atmospheric loading of ammonium (NH4) and nitrate/nitrite (NO2/3) and decreasing trends in total phosphorus (P) and sulfate (SO4) to Flathead Lake, Montana, from 1985 to 2004. Atmospheric loading of NO2/3 and NH4 increased by 48 and 198% and total P and SO4 decreased by 135 and 39%. The molar ratio of TN:TP also increased significantly. Severe air inversions occurred periodically year-round and increased the potential for substantial nutrient loading from even small local sources. Correlations between our loading data and various measures of air quality in the basin (e.g., particulate matter dust and smoke are important sources. Ammonium was the primary form of N in atmospheric deposition, whereas NO3 was the primary N form in tributary inputs. Atmospheric loading of NH4 to Flathead Lake averaged 44% of the total load and on some years exceeded tributary loading. Primary productivity in the lake is colimited by both N and P most of the year; and in years of high atmospheric loading of inorganic N, deposition may account for up to 6.9% of carbon converted to biomass.

  4. 21 CFR 520.310 - Caramiphen ethanedisulfonate and ammonium chloride tablets. (United States)


    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Caramiphen ethanedisulfonate and ammonium chloride... § 520.310 Caramiphen ethanedisulfonate and ammonium chloride tablets. (a) Specifications. Each tablet contains 10 milligrams of 5st caramiphen ethanedisulfonate and 80 milligrams of ammonium chloride.1 1...

  5. 40 CFR 415.240 - Applicability; description of the ammonium chloride production subcategory. (United States)


    ... ammonium chloride production subcategory. 415.240 Section 415.240 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Ammonium Chloride Production Subcategory § 415.240 Applicability; description of the ammonium chloride production subcategory. The provisions of this subpart are applicable to...

  6. 77 FR 21527 - Ammonium Nitrate From Russia: Correction to Notice of Opportunity To Request Administrative Review (United States)


    ... International Trade Administration Ammonium Nitrate From Russia: Correction to Notice of Opportunity To Request... of the antidumping duty orders and inadvertently omitted Ammonium Nitrate from Russia, POR 5/2/2011-3... include the Ammonium Nitrate from Russia administrative review in the referenced notice. Dated: April...

  7. 77 FR 32669 - Ammonium Nitrate from Ukraine Institution of a Five-Year Review (United States)


    ... COMMISSION Ammonium Nitrate from Ukraine Institution of a Five-Year Review AGENCY: United States... determine whether revocation of the antidumping duty order on ammonium nitrate from Ukraine would be likely... ammonium nitrate from Ukraine (66 FR 47451). Following the five-year reviews by Commerce and the...

  8. Formation of the natural sulfate aerosol

    Energy Technology Data Exchange (ETDEWEB)

    Kerminen, V.M.; Hillamo, R.; Maekinen, M.; Virkkula, A.; Maekelae, T.; Pakkanen, T. [Helsinki Univ. (Finland). Dept. of Physics


    Anthropogenic sulfate aerosol, together with particles from biomass burning, may significantly reduce the climatic warming due to man-made greenhouse gases. The radiative forcing of aerosol particles is based on their ability to scatter and absorb solar radiation (direct effect), and on their influences on cloud albedos and lifetimes (indirect effect). The direct aerosol effect depends strongly on the size, number and chemical composition of particles, being greatest for particles of 0.1-1 {mu}m in diameter. The indirect aerosol effect is dictated by the number of particles being able to act as cloud condensation nuclei (CCN). For sulfate particles, the minimum CCN size in tropospheric clouds is of the order of 0.05-0.2 {mu}m. To improve aerosol parameterizations in future climate models, it is required that (1) both primary and secondary sources of various particle types will be characterized at a greater accuracy, and (2) the influences of various atmospheric processes on the spatial and temporal distribution of these particles and their physico-chemical properties are known much better than at the present. In estimating the climatic forcing due to the sulfate particles, one of the major problems is to distinguish between sulfur from anthropogenic sources and that of natural origin. Global emissions of biogenic and anthropogenic sulfate pre-cursors are comparable in magnitude, but over regional scales either of these two source types may dominate. The current presentation is devoted to discussing the natural sulfate aerosol, including the formation of sulfur-derived particles in the marine environment, and the use of particulate methanesulfonic acid (MSA) as a tracer for the natural sulfate

  9. Molybdate transport through the plant sulfate transporter SHST1. (United States)

    Fitzpatrick, Kate L; Tyerman, Stephen D; Kaiser, Brent N


    Molybdenum is an essential micronutrient required by plants. The mechanism of molybdenum uptake in plants is poorly understood, however, evidence has suggested that sulfate transporters may be involved. The sulfate transporter from Stylosanthes hamata, SHST1, restored growth of the sulfate transport yeast mutant, YSD1, on media containing low amounts of molybdate. Kinetic analysis using 99MoO4(2-) demonstrated that SHST1 enhanced the uptake of molybdate into yeast cells at nM concentrations. Uptake was not inhibited by sulfate, but sulfate transport via SHST1 was reduced with molybdate. These results are the first measurement of molybdate transport by a characterised plant sulfate transport protein.

  10. Selective sulfation of carrageenans and the influence of sulfate regiochemistry on anticoagulant properties. (United States)

    de Araújo, Cristiano A; Noseda, Miguel D; Cipriani, Thales R; Gonçalves, Alan G; Duarte, Maria Eugênia R; Ducatti, Diogo R B


    Sulfated polysaccharides are recognized for their broad range of biological activities, including anticoagulant properties. The positions occupied by the sulfate groups are often related to the level of the inherent biological activity. Herein the naturally sulfated galactans, kappa-, iota- and theta-carrageenan, were additionally sulfated by regioselective means. The anticoagulant activity of the resulting samples was then studied using the aPTT in vitro assay. The influence of sulfate regiochemistry on the anticoagulant activity was evaluated. From kappa-carrageenan three rare polysaccharides were synthesized, one of them involved a synthetic route with an amphiphilic polysaccharide intermediate containing pivaloyl groups. Iota- and theta-carrageenan were utilized in a selective C6 sulfation at β-D-Galp units to produce different structures comprising trisulfated diads. All the samples were characterized by NMR (1D and 2D). The resulting aPPT measurements suggested that sulfation at C2 of 3,6-anhydro-α-D-Galp and C6 of β-D-Galp increased the anticoagulant activity.

  11. Synthesis of benzo[g]indeno[2,1-b]quinoline derivatives via four-component and one-pot synthesis in presence of 3-methyl-1-sulfonic acid imidazolium hydrogen sulfate

    Institute of Scientific and Technical Information of China (English)

    Nader Ghaffari Khaligh


    A simple and facile synthesis of 12-arylbenzo[g]indeno[2,1-b]quinoline-6,11,13-trione deriv-atives was accomplished by the one-pot condensation of 2-hydroxynaphthalene-1,4-dione, aryl aldehydes, 2H-indene-1,3-dione, and ammonium acetate under solvent-free conditions in the presence of a Brönsted ionic liquid catalyst, namely 3-methyl-1-sulfonic acid imidazolium hydrogen sulfate.

  12. Anaerobic ammonium oxidation, denitrification and dissimilatory nitrate reduction to ammonium in the East China Sea sediment

    Directory of Open Access Journals (Sweden)

    G. D. Song


    Full Text Available Benthic nitrogen transformation pathways were investigated in the sediment of the East China Sea in June of 2010 using the 15N isotope pairing technique. Slurry incubations indicated that denitrification, anammox and dissimilatory nitrate reduction to ammonium (DNRA as well as nitrate release by nitrate storing organisms occurred in the East China Sea sediments. These four processes did not exist independently, the nitrate release therefore diluted the 15N labeling fraction of NO3−, a part of the 15NH4+ derived from DNRA also formed 30N2 via anammox. Therefore current methods of rate calculations led to over and underestimations of anammox and denitrification respectively. Following the procedure outlined in Thampdrup and Dalsgaard (2002, denitrification rates were slightly underestimated by on average 6% without regard to the effect of nitrate release, while this underestimation could be counteracted by the presence of DNRA. On the contrary, anammox rates calculated from 15NO3− experiment were significantly overestimated by 42% without considering nitrate release. In our study this overestimation could only be compensated 14% by taking DNRA into consideration. In a parallel experiment amended with 15NH4+ + 14NO3−, anammox rates were not significantly influenced by DNRA due to the high background of 15NH4+ addition. Excluding measurements in which bioirrigation was present, integrated denitrification rates decreased from 10 to 4 mmol N m−2 d−1 with water depth, while integrated anammox rates increased from 1.5 to 4.0 mmol N m−2 d−1. Consequently, the relative contribution of anammox to the total N-loss increased from 13% at the shallowest site near the Changjiang estuary to 50% at the deepest site on the outer shelf. This study represents the first time in which anammox has been demonstrated to play a significant role in benthic nitrogen cycling in the East China Sea sediment, especially on the outer shelf. N

  13. Synthesis, antimicrobial activity of lamotrigine and its ammonium derivatives

    Indian Academy of Sciences (India)

    Yong Qian; Peng-Cheng Lv; Lei Shi; Rui-Qin Fang; Zhong-Cheng Song; Hai-Liang Zhu


    Antiepileptic drug lamotrigine and its thirteen ammonium salt complexes (4a-4m) were synthesized and characterized by IR, elemental analysis, 1H-NMR, and MS spectral methods. Many of the ammonium salts (4a-4m) were first reported. Furthermore, the crystal structure of compound 3 was determined by single crystal X-ray diffraction analysis. All these complexes were tested in vitro for their antibacterial activity (Bacillus subtilis, Staphylococcus aureus, Enterococus faecalis, Escherichia coli, Pseudomonas aeruginosa and Enterobacter cloacae). The results indicated that most of the complexes showed good antibacterial activity against Gram-positive (B. subtilis, S. aureus and S. faecalis), but showed mild, even inactive against Gram-negative bacterial strains.

  14. Thorium adsorption behaviour on mixed ammonium lanthanum oxalate, LAOX

    Energy Technology Data Exchange (ETDEWEB)

    Valentini Ganzerli, M.T.; Maggi, L.; Crespi Caramella, V


    The cation-exchange properties of mixed ammonium lanthanum oxalate, LAOX, were studied by batch equilibration as a function of the concentration of some cations, such as alkaline earths or ammonium and of some anions and acids. The distribution coefficients for thorium are high, while U(VI) is not adsorbed over a large acidity range. Thus, the separation of thorium from uranium may be successfully carried out. The experimental conditions of adsorption, elution and recovery of thorium were investigated as well, by using chromatographic columns filled with LAOX, in order to set best the separation conditions from uranyl ions. Instrumental neutron activation analysis, ICP emission spectrometry and the UV spectrometry were used to evaluate the thorium, uranium and lanthanum concentrations00.

  15. Thermal stability assessment of anti-explosive ammonium nitrate

    Institute of Scientific and Technical Information of China (English)

    Lijin Shen; Xuguang Wang


    The explosivity experiment of anti-explosive ammonium nitrate (AEAN) shows that the explosive characteristic of AEAN is eliminated. The adiabatic decompositions of ammonium nitrate and AEAN were investigated with an accelerating rate calorimeter (ARC). The curves of thermal decomposition temperature and pressure versus time, self-heating rate and pressure versus temperature for two systems were obtained. The kinetic parameters such as apparent activation energy and pre-exponential factor were calculated.The safety of AEAN was analyzed. It was indicated that AEAN has a higher thermal stability than AN. At the same time, it can be shown that the elimination of its explosive characteristic is due to the improvement on the thermal stability of AEAN.

  16. Anaerobic ammonium oxidation in a bioreactor treating slaughterhouse wastewater

    Directory of Open Access Journals (Sweden)

    V. Reginatto


    Full Text Available Ammonium oxidation was thought to be an exclusively aerobic process; however, as recently described in the literature, it is also possible under anaerobic conditions and this process was named ANAMMOX. This work describes the operation of a system consisting of a denitrifying reactor coupled to a nitrifying reactor used for removal of nitrogen from slaughterhouse wastewater. During operation of the denitrifying reactor an average nitrogen ammonium removal rate of 50 mg/Ld was observed. This biomass was used to seed a second reactor, operated in repeated fed batch mode, fed with synthetic medium specific to the growth of bacteria responsible for the ANAMMOX process. The nitrogen loading rate varied between 33 and 67 mgN/Ld and average nitrogen removal was 95% and 40%, respectively. Results of fluorescence in situ hybridization (FISH confirmed the presence of anammox-like microorganisms in the enriched biomass.

  17. Preparation of nanodispersed titania using stabilized ammonium nitrate melts

    KAUST Repository

    Raciulete, Monica


    An expedite one-step approach using simple precursors has been proposed to obtain metallic oxide compounds and exemplified by preparation of highly dispersed TiO2. The technique consists in heating to 400500 °C of molten ammonium nitrate stabilized with an organic nitrogen-containing compound (urea, melamine, ammonium oxalate) and containing dissolved metal salt precursor (TiOCl2). The crystallites of the resulting TiO2 demonstrated variable size and shape as a function of stabilizer used. Their activity in photocatalytic oxidation of formic acid also depends on the nature of the stabilizer. The catalysts as-prepared showed high photocatalytic performance, superior to that of the Degussa P25 reference. Nitrogen containing stabilizers play a double role of increasing the process safety and modifying the properties of the solid products. © 2010 Elsevier Inc. All rights reserved.

  18. The nitrogen Sternheimer antishielding factor in the ammonium ion (United States)

    Fowler, P. W.; Kelly, H. M.; Brown, R. J. C.


    Coupled Hartree-Fock calculations in various basis sets yield values in the range 6.7 to 6.8 for the Sternheimer antishielding factor (1 - γ ∞) of the nitrogen nucleus in the ammonium ion. These are in substantial agreement with the value of 9 that is obtained from a model of measured relaxation times in solid ammonium chloride when allowance is made for effects of the crystalline environment on the chloride ion Sternheimer antishielding factor. Other experimental estimates of the nitrogen Sternheimer factor are discussed. The new value is used to derive cation field gradients from measured quadrupole coupling constants in solid NH 4ReO 4 and NH 4IO 4.

  19. Activation and transfer of sulfate in biological systems (1960); Activation biologique du sulfate et son transfert (1960)

    Energy Technology Data Exchange (ETDEWEB)

    Chapeville, F. [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires


    It examines in this review the successive stages of active sulfate formation and its role in biological synthesis of sulfuric esters. The possible role of active sulfate as intermediary in sulfate reduction is also discussed. (author) [French] On examine dans cette etude les stades successifs de la mise en evidence du sulfate actif, son role dans la formation des esters sulfuriques de natures diverses, ainsi que sa participation eventuelle comme intermediaire au cours de la reduction du sulfate. On decrit aussi un procede de preparation du systeme biologique, generateur du sulfate actif et une methode de synthese chimique. (auteur)

  20. Ammonium sulphate precipitation overestimates titres of anti-peptide antisera. (United States)

    Roth, B; Barkas, T


    Precipitation by 50% final saturation of ammonium sulphate, a method commonly used to estimate titres and affinity constants of antibodies, was found consistently to overestimate the titre of anti-peptide antisera when compared with other antibody precipitants. The effect could not be attributed to non-IgG fractions, and similar overestimations were found when pure IgG was used. We suggest that the lower values represent a more physiologically relevant estimation.

  1. Recovering germanium from coal ash by chlorination with ammonium chloride

    Institute of Scientific and Technical Information of China (English)


    A new process of enriching germanium from coal ash was developed. The process involves in mixing the coal ash and ammonium chloride and then roasting the mixture to produce germanium chloride that is then absorbed by dilute hydrochloric acid and hydrolyzed to germanium oxide. The germanium recovery reached to 80.2% at the optimum condition: mass ratio of NH4Cl/coal ash is 0.15, roasting temperature 400℃ and roasting time 90 min.

  2. Ammonium photo-production by heterocytous cyanobacteria: potentials and constraints. (United States)

    Grizeau, Dominique; Bui, Lan Anh; Dupré, Catherine; Legrand, Jack


    Over the last decades, production of microalgae and cyanobacteria has been developed for several applications, including novel foods, cosmetic ingredients and more recently biofuel. The sustainability of these promising developments can be hindered by some constraints, such as water and nutrient footprints. This review surveys data on N2-fixing cyanobacteria for biomass production and ways to induce and improve the excretion of ammonium within cultures under aerobic conditions. The nitrogenase complex is oxygen sensitive. Nevertheless, nitrogen fixation occurs under oxic conditions due to cyanobacteria-specific characteristics. For instance, in some cyanobacteria, the vegetative cell differentiation in heterocyts provides a well-adapted anaerobic microenvironment for nitrogenase protection. Therefore, cell cultures of oxygenic cyanobacteria have been grown in laboratory and pilot photobioreactors (Dasgupta et al., 2010; Fontes et al., 1987; Moreno et al., 2003; Nayak & Das, 2013). Biomass production under diazotrophic conditions has been shown to be controlled by environmental factors such as light intensity, temperature, aeration rate, and inorganic carbon concentration, also, more specifically, by the concentration of dissolved oxygen in the culture medium. Currently, there is little information regarding the production of extracellular ammonium by heterocytous cyanobacteria. This review compares the available data on maximum ammonium concentrations and analyses the specific rate production in cultures grown as free or immobilized filamentous cyanobacteria. Extracellular production of ammonium could be coupled, as suggested by recent research on non-diazotrophic cyanobacteria, to that of other high value metabolites. There is little information available regarding the possibility for using diazotrophic cyanobacteria as cellular factories may be in regard of the constraints due to nitrogen fixation.

  3. Proton- and ammonium- sensing by histaminergic neurons controlling wakefulness.

    Directory of Open Access Journals (Sweden)

    Yvgenij eYanovsky


    Full Text Available Orexinergic and histaminergic neurons in the posterior hypothalamus are involved in the control of arousal. Extracellular levels of acid /CO2 are fundamental physicochemical signals controlling wakefulness and breathing. Acidification excites orexinergic neurons like the chemosensory neurons in the brain stem. Hypercapnia induces c-Fos expression, a marker for increased neuronal activity, in the rat histaminergic tuberomamillary nucleus (TMN, but the mechanisms of this excitation are unknown. Acid-sensing ion channels (ASICs are gated by protons and also by ammonium. Recordings in rat brain slices revealed now that acidification within the physiological range (pH from 7.3 to 7.0 as well as ammonium chloride (5mM excite histaminergic neurons. We detected variable combinations of 4 known types of ASICs in single TMN neurons, along with the pharmacological properties of pH-induced current. At pH 7.0 however, activation of ASICs in TMN neurons was negligible. Block of type I metabotropic glutamate receptors abolished proton- but not ammonium- induced excitation. Mouse TMN neurons were identified within a novel HDC-Cre transgenic reporter mouse line. In contrast to the rat these lacked pH 7.0-induced excitation and showed only a minimal response to the mGluR I agonist DHPG (0.5µM. Ammonium-induced excitation was similar in mouse and rat. Thus glutamate, which is released by glial cells and orexinergic axons amplifies CO2/acid-induced arousal through the recruitment of the histaminergic system in rat but not in mouse. These results are relevant for the understanding of neuronal mechanisms controlling H+/CO2-induced arousal in hepatic encephalopathy and obstructive sleep apnoea. The new HDC-Cre mouse model will be a useful tool for studying the physiological and pathophysiological roles of the histaminergic system.

  4. Nanomodified vermiculite NMV - a new material for recycling ammonium nitrogen (United States)

    Rama, Miradije; Laiho, Taina; Eklund, Olav; Lehto, Kirsi; Shebanov, Alex; Smått, Jan-Henrik


    Vermiculites ((Mg,Fe,Al)3(Al,Si)4O10(OH)24H2O) are naturally occurring minerals from hydromica group with a high cation exchange capacity and large surface area. Since vermiculite is a hydrated mineral, its structure can be changed with heat. In this study vermiculite samples were heated in an oven until the interlayer distance of them diminished from 14 Å to 11.7 Å. This method for improving vermiculites intake of ammonium ions by heating, is an invention made at the University of Turku. Nanomodified vermiculite (NMV) is able to absorb up to 4.7 wt% of ammonium. NMV can be used as an efficient filter and immobilizer of ammonium in different environments. NMV has been efficiently tested on waste water from a biogas plant, human urine, combustion experiments, industrial chimneys, excrements from farms etc. Ammonium doped vermiculite (ADV) is further developed for fertilizer use. Performed experiments have testified the usability of ADV as a fertilizer. At first step the NMV was processed with the reject water from a biogas plant, were it absorbed NH4+ into the lattice. At second, the ADV was used as nutrient source for garden plants. Geraniums and begonias were used as test plants of the work. Plant growth rate was evaluated based on plant weight. Results showed that significant increase of the growth of geraniums and of begonias were observed when comparing to those cultivations where plants have got normal fertilization. Moreover, ADV has been tested as a fertilizer in greenhouse experiments with spruces and pines. After five months, the weight of the plants that had grown in a substrate containing ADV was 10 times the weight of plants growing in the reference substrate.

  5. Process optimization of rare earth and aluminum leaching from weathered crust elution-deposited rare earth ore with compound ammonium salts

    Institute of Scientific and Technical Information of China (English)

    何正艳; 张臻悦; 余军霞; 徐志高; 池汝安


    In order to intensify the leaching process of rare earth (RE) and reduce the impurities in the leachate, ammonium chloride (NH4Cl) and ammonium nitrate (NH4NO3) were mixed as a compound leaching agent to treat the weathered crust elution-deposited RE ore. Effects of molar ratio of NH4Cl and NH4NO3, ammonium (NH4+) concentration, leaching agent pH and flow rate on the leaching process of RE were studied and evaluated by the chromatographic plate theory. Leaching process of the main impurity alu-minium (Al) was also discussed in detail. Results showed that a higher initial ammonium concentration in a certain range could en-hance the mass transfer process of RE and Al by providing a driving force to overcome the resistance of diffusion. pH almost had no effects on the mass transfer efficiency of RE and Al in the range of 4 to 8. The relationship between the flow rate and height equiva-lent to a theoretical plate (HETP) could fit well with the Van Deemter equation, and the flow rate at the lowest HETP was determined. The optimum conditions of column leaching for RE and Al were 1:1 (molar ratio) of NH4Cl and NH4NO3, 0.2 mol/L of ammonium concentration, pH 4–8 of leaching agent and 0.5 mL/min of flow rate. Under this condition, the mass transfer efficiency of RE was improved, but no change was observed for Al compared with the most widely used ammonium sulfate. Moreover, the significant dif-ference value (around 20 mL) of retention volume at the peak concentration between RE and Al provided a possibility for their sepa-ration. It suggested the potential application of the novel compound leaching agent (NH4Cl/NH4NO3). It was found that the relative concentration of RE in the leachate could be easily obtained by monitoring the pH of leachate.

  6. Structural basis for Mep2 ammonium transceptor activation by phosphorylation. (United States)

    van den Berg, Bert; Chembath, Anupama; Jefferies, Damien; Basle, Arnaud; Khalid, Syma; Rutherford, Julian C


    Mep2 proteins are fungal transceptors that play an important role as ammonium sensors in fungal development. Mep2 activity is tightly regulated by phosphorylation, but how this is achieved at the molecular level is not clear. Here we report X-ray crystal structures of the Mep2 orthologues from Saccharomyces cerevisiae and Candida albicans and show that under nitrogen-sufficient conditions the transporters are not phosphorylated and present in closed, inactive conformations. Relative to the open bacterial ammonium transporters, non-phosphorylated Mep2 exhibits shifts in cytoplasmic loops and the C-terminal region (CTR) to occlude the cytoplasmic exit of the channel and to interact with His2 of the twin-His motif. The phosphorylation site in the CTR is solvent accessible and located in a negatively charged pocket ∼30 Å away from the channel exit. The crystal structure of phosphorylation-mimicking Mep2 variants from C. albicans show large conformational changes in a conserved and functionally important region of the CTR. The results allow us to propose a model for regulation of eukaryotic ammonium transport by phosphorylation.

  7. Removal of chloridazon by natural and ammonium kerolite samples (United States)

    Socías-Viciana, M. M.; Tévar de Fez, J.; Ureña-Amate, M. D.; González-Pradas, E.; Fernández-Pérez, M.; Flores-Céspedes, F.


    The adsorption of chloridazon (5-amino-4-chloro-2-phenylpyridazin-3(2H)-one) on natural and ammonium kerolite samples from aqueous solution at 10, 25 and 40 °C has been studied by using batch experiments. The experimental data points were fitted to the Langmuir equation in order to calculate the adsorption capacities ( Xm) of the samples; two straight lines were obtained, which indicates that the adsorption process takes place in two different stages. Values for Xm1 (first stage) ranged from 1.1 × 10 -2 mol kg -1 for natural kerolite at 40 °C up to 5.1 × 10 -2 mol kg -1 for ammonium kerolite at 10 °C and the values for Xm2 (second stage) ranged from 9.1 × 10 -2 mol kg -1 for natural kerolite at 40 °C up to 14 × 10 -2 mol kg -1 for natural kerolite at 10 °C. The adsorption experiments showed on the one hand, that the ammonium kerolite is more effective than natural kerolite to adsorb chloridazon in the range of temperature studied and on the other hand, that the lower temperature, the more effective the adsorption of chloridazon on the adsorbents studied.

  8. Extraction Factor Of Pure Ammonium Paratungstate From Tungsten Scraps

    Directory of Open Access Journals (Sweden)

    Pee J.-H.


    Full Text Available Typical oxidation process of tungsten scraps was modified by the rotary kiln with oxygen burner to increase the oxidation rate of tungsten scraps. Also to accelerate the solubility of solid oxidized products, the hydrothermal reflux method was adapted. By heating tungsten scraps in rotary kiln with oxygen burner at around 900° for 2hrs, the scraps was oxidized completely. Then oxidized products (WO3 and CoWO4 was fully dissolved in the solution of NaOH by hydrothermal reflux method at 150° for 2hrs. The dissolution rate of oxidized products was increased with increasing the reaction temperature and concentration of NaOH. And then CaWO4 and H2WO4 could be generated from the aqueous sodium tungstate solution. Ammonium paratungstate (APT also could be produced from tungstic acid using by aqueous ammonium solution. The morphologies (cubic and plate types of APT was controlled by the stirring process of purified solution of ammonium paratungstate.

  9. Ammonium nitrogen in fetuses of urea-treated sheep. (United States)

    Yelverton, C C; Roller, M H; Swanson, R N


    Eight pregnant Southdown ewes were treated (by drench) with 12.5 ml of 3.3 M urea solution per kilogram of body weight, and ammonium nitrogen concentrations of blood and tissues of these ewes and their fetuses were measured and compared with those of control ewes (given water by drench) and their fetuses. Blood ammonium nitrogen (BAN) and tissue ammonium nitrogen (TAN) concentrations for liver, kidney, spleen, and muscle of ewes and fetuses were determined by an ion-exchange procedure. Samples of blood were collected before treatment, at 30, 90 and 150 minutes after treatment, and at death of the dam. The principal ewes had increasing BAN concentrations with time after drench, and their fetuses had significantly greater (P less than 0.01) BAN concentrations than fetuses from control ewes. All fetuses were alive after death of the dams and had lower TAN values than their dams. The differences in ammonia concentrations between ewes and fetuses were larger in the principal group than in the control group. Except for ewe muscle and fetal liver, all tissues of principals had significantly greater (P less than 0.01) TAN concentrations than those of controls. Muscle of principal ewes and hepatic tissues of their fetuses had greater (P less than 0.05) TAN concentrations than those of control ewes and their fetuses.

  10. Sulfate-reducing bacteria in anaerobic bioreactors.

    NARCIS (Netherlands)

    Oude Elferink, S.J.W.H.


    The treatment of industrial wastewaters containing high amounts of easily degradable organic compounds in anaerobic bioreactors is a well-established process. Similarly, wastewaters which in addition to organic compounds also contain sulfate can be treated in this way. For a long time, the occurrenc

  11. Plasmin Regulation through Allosteric, Sulfated, Small Molecules

    Directory of Open Access Journals (Sweden)

    Rami A. Al-Horani


    Full Text Available Plasmin, a key serine protease, plays a major role in clot lysis and extracellular matrix remodeling. Heparin, a natural polydisperse sulfated glycosaminoglycan, is known to allosterically modulate plasmin activity. No small allosteric inhibitor of plasmin has been discovered to date. We screened an in-house library of 55 sulfated, small glycosaminoglycan mimetics based on nine distinct scaffolds and varying number and positions of sulfate groups to discover several promising hits. Of these, a pentasulfated flavonoid-quinazolinone dimer 32 was found to be the most potent sulfated small inhibitor of plasmin (IC50 = 45 μM, efficacy = 100%. Michaelis-Menten kinetic studies revealed an allosteric inhibition of plasmin by these inhibitors. Studies also indicated that the most potent inhibitors are selective for plasmin over thrombin and factor Xa, two serine proteases in coagulation cascade. Interestingly, different inhibitors exhibited different levels of efficacy (40%–100%, an observation alluding to the unique advantage offered by an allosteric process. Overall, our work presents the first small, synthetic allosteric plasmin inhibitors for further rational design.

  12. Intravenous magnesium sulfate therapy in severe asthma

    Directory of Open Access Journals (Sweden)

    Mohd. Al-Ajmi


    Full Text Available A 22-year-old female, known asthmatic since seven years, developed severe bronchospasm in the preop-erative period. Bronchospasm remained unresponsive to the inhaled beta-agonist plus anticholinergic, IV ami-nophylline and hydrocortisone but responded quickly with magnesium sulfate® ( PSI, KSA infusion 1.25gm in 100ml normal saline over 20 minutes and another 1.25 gm over next 30 minutes as the initial infusion showed improvement in her clinical symptoms. Within half an hour of administering the 1st infusion of magnesium sulfate (1.25 gm the respiratory rate started reducing, rhonchi became less, SpO 2 came upto 92% and re-mained always above 90%. Encouraged by this result IV magnesium sulfate 2.5 gm in 500 ml normal saline was infused over next 24 hours along with alternate salbutamol and ipratropium nebulization every 6 hourly. With this treatment regimen the patient became asymptomatic within next 24 hours with normal clinical parameters and FEV 1 value. Hence it may be concluded that IV magnesium sulfate can be considered for patients with acute severe asthma who do not respond to standard therapeutic medications.


    NARCIS (Netherlands)



    Dissimilatory sulfate reduction is carried out by a heterogeneous group of bacteria and archaea that occur in environments with temperatures up to 105 degrees C. As a group together they have the capacity to metabolize a wide variety of compounds ranging from hydrogen via typical organic fermentatio

  14. Sulfate transport in Penicillium chrysogenum plasma membranes

    NARCIS (Netherlands)

    Hillenga, Dirk J.; Versantvoort, Hanneke J.M.; Driessen, Arnold J.M.; Konings, Wil N.


    Transport studies with Penicillium chrysogenum plasma membranes fused with cytochrome c oxidase liposomes demonstrate that sulfate uptake is driven by the transmembrane pH gradient and not by the transmembrane electrical potential. Ca2+ and other divalent cations are not required. It is concluded th

  15. Bacterial transport of sulfate, molybdate, and related oxyanions. (United States)

    Aguilar-Barajas, Esther; Díaz-Pérez, César; Ramírez-Díaz, Martha I; Riveros-Rosas, Héctor; Cervantes, Carlos


    Sulfur is an essential element for microorganisms and it can be obtained from varied compounds, sulfate being the preferred source. The first step for sulfate assimilation, sulfate uptake, has been studied in several bacterial species. This article reviews the properties of different bacterial (and archaeal) transporters for sulfate, molybdate, and related oxyanions. Sulfate uptake is carried out by sulfate permeases that belong to the SulT (CysPTWA), SulP, CysP/(PiT), and CysZ families. The oxyanions molybdate, tungstate, selenate and chromate are structurally related to sulfate. Molybdate is transported mainly by the high-affinity ModABC system and tungstate by the TupABC and WtpABC systems. CysPTWA, ModABC, TupABC, and WtpABC are homologous ATP-binding cassette (ABC)-type transporters with similar organization and properties. Uptake of selenate and chromate oxyanions occurs mainly through sulfate permeases.

  16. Pregnenolone Sulfate: From Steroid Metabolite to TRP Channel Ligand

    Directory of Open Access Journals (Sweden)

    Christian Harteneck


    Full Text Available Pregnenolone sulfate is a steroid metabolite with a plethora of actions and functions. As a neurosteroid, pregnenolone sulfate modulates a variety of ion channels, transporters, and enzymes. Interestingly, as a sulfated steroid, pregnenolone sulfate is not the final- or waste-product of pregnenolone being sulfated via a phase II metabolism reaction and renally excreted, as one would presume from the pharmacology textbook knowledge. Pregnenolone sulfate is also the source and thereby the starting point for subsequent steroid synthesis pathways. Most recently, pregnenolone sulfate has been functionally “upgraded” from modulator of ion channels to an activating ion channel ligand. This review will focus on molecular aspects of the neurosteroid, pregnenolone sulfate, its metabolism, concentrations in serum and tissues and last not least will summarize the functional data.

  17. 21 CFR 524.960 - Flumethasone, neomycin sulfate, and polymyxin B sulfate ophthalmic solutions. (United States)


    ... sulfate, with or without hydroxypropyl methylcellulose. (b) Sponsor. See No. 000856 in § 510.600(c) of this chapter. (c) Conditions of use—(1) Amount—(i) Preparation containing hydroxypropyl...

  18. Quaternary ammonium salt N-(dodecyloxycarboxymethyl)-N,N,N-trimethyl ammonium chloride induced alterations in Saccharomyces cerevisiae physiology

    Indian Academy of Sciences (India)



    We investigated the influence of the quaternary ammonium salt (QAS) called IM (N-(dodecyloxycarboxymethyl)-N,N,N-trimethyl ammonium chloride) on yeast cells of the parental strain and the IM-resistant mutant (EO25 IMR)growth. The phenotype of this mutant was pleiotropic. The IMR mutant exhibited resistance to ethanol, osmotic shockand oxidative stress, as well as increased sensitivity to UV. Moreover, it was noted that mutant EO25 appears to havean increased resistance to clotrimazole, ketoconazole, fluconazole, nystatin and cycloheximide. It also toleratedgrowth in the presence of crystal violet, DTT and metals (selenium, tin, arsenic). It was shown that the presence ofIM decreased ergosterol level in mutant plasma membrane and increased its unsaturation. These results indicatechanges in the cell lipid composition. Western blot analysis showed the induction of Pma1 level by IM. RT-PCRrevealed an increased PMA1 expression after IM treatment.

  19. Sources of sulfate supporting anaerobic metabolism in a contaminated aquifer (United States)

    Ulrich, G.A.; Breit, G.N.; Cozzarelli, I.M.; Suflita, J.M.


    Field and laboratory techniques were used to identify the biogeochemical factors affecting sulfate reduction in a shallow, unconsolidated alluvial aquifer contaminated with landfill leachate. Depth profiles of 35S-sulfate reduction rates in aquifer sediments were positively correlated with the concentration of dissolved sulfate. Manipulation of the sulfate concentration in samples revealed a Michaelis-Menten-like relationship with an apparent Km and Vmax of approximately 80 and 0.83 ??M SO4-2??day-1, respectively. The concentration of sulfate in the core of the leachate plume was well below 20 ??M and coincided with very low reduction rates. Thus, the concentration and availability of this anion could limit in situ sulfate-reducing activity. Three sulfate sources were identified, including iron sulfide oxidation, barite dissolution, and advective flux of sulfate. The relative importance of these sources varied with depth in the alluvium. The relatively high concentration of dissolved sulfate at the water table is attributed to the microbial oxidation of iron sulfides in response to fluctuations of the water table. At intermediate depths, barite dissolves in undersaturated pore water containing relatively high concentrations of dissolved barium (???100 ??M) and low concentrations of sulfate. Dissolution is consistent with the surface texture of detrital barite grains in contact with leachate. Laboratory incubations of unamended and barite-amended aquifer slurries supported the field observation of increasing concentrations of barium in solution when sulfate reached low levels. At a deeper highly permeable interval just above the confining bottom layer of the aquifer, sulfate reduction rates were markedly higher than rates at intermediate depths. Sulfate is supplied to this deeper zone by advection of uncontaminated groundwater beneath the landfill. The measured rates of sulfate reduction in the aquifer also correlated with the abundance of accumulated iron sulfide

  20. Nanocrystalline cellulose with various contents of sulfate groups. (United States)

    Voronova, M I; Surov, O V; Zakharov, A G


    Properties of films derived from aqueous nanocrystalline cellulose dispersions by water evaporation depend on concentration of sulfate groups. Namely type of thermodestruction and surface morphology change as a function of contents of sulfate groups. Surface roughness increases and water adsorption enhances with increasing sulfate groups content particularly at high relative pressure.

  1. 21 CFR 522.1484 - Neomycin sulfate sterile solution. (United States)


    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Neomycin sulfate sterile solution. 522.1484... § 522.1484 Neomycin sulfate sterile solution. (a) Specifications. Each milliliter of sterile aqueous solution contains 50 milligrams of neomycin sulfate (equivalent to 35 milligrams of neomycin base).1...

  2. 21 CFR 524.1484a - Neomycin sulfate ophthalmic ointment. (United States)


    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Neomycin sulfate ophthalmic ointment. 524.1484a... § 524.1484a Neomycin sulfate ophthalmic ointment. (a) Specifications. Each gram of the ointment contains 5 milligrams of neomycin sulfate equivalent in activity to 3.5 milligrams of neomycin base....

  3. Thermophilic Sulfate-Reducing Bacteria in Cold Marine Sediment

    DEFF Research Database (Denmark)



    C to search for presence of psychrophilic, mesophilic and thermophilic sulfate-reducing bacteria. Detectable activity was initially only in the mesophilic range, but after a lag phase sulfate reduction by thermophilic sulfate-reducing bacteria were observed. No distinct activity of psychrophilic...

  4. De Novo Sequencing of Complex Mixtures of Heparan Sulfate Oligosaccharides

    NARCIS (Netherlands)

    Huang, Rongrong; Zong, Chengli; Venot, Andre; Chiu, Yulun; Zhou, Dandan; Boons, Geert-Jan; Sharp, Joshua S


    Here, we describe the first sequencing method of a complex mixture of heparan sulfate tetrasaccharides by LC-MS/MS. Heparin and heparan sulfate (HS) are linear polysaccharides that are modified in a complex manner by N- and O-sulfation, N-acetylation, and epimerization of the uronic acid. Heparin an

  5. Stability-indicating RP-HPLC method for simultaneous estimation of levosalbutamol sulfate and theophylline in combined dosage form

    Directory of Open Access Journals (Sweden)

    Sagar Suman Panda


    Full Text Available A novel, simple, accurate and precise RP-HPLC method for simultaneous determination of levosalbutamol sulfate and theophylline has been developed and validated. Separation was achieved on a Phenomenex; C18 column (250 mm × 4.6 mm i.d., 5 µm using methanol: 10 mM TBAHS(tetrabutyl ammonium hydrogen sulfate (50:50, v/v as mobile phase at flow rate of 1.0 mL.min-1. The UV detection wavelength was 274 nm. The linearity is obeyed over a concentration range of 0.5-150 µg.mL-1 with correlation coefficient of 0.999 for both the drugs. The proposed method was validated by determining accuracy, precision, stability and system suitability parameters. The method was found to be robust. Specificity of the method was determined by subjecting the drugs to various stress conditions like acid, alkali, oxidation, thermal and photolytic degradation. The method was used successfully for the simultaneous determination of levosalbutamol sulfate and theophylline in syrup dosage form.

  6. Acid Sulfate Alteration in Gusev Crater, Mars (United States)

    Morris, R. V.; Ming, D. W.; Catalano, J. G.


    The Mars Exploration Rover (MER) Spirit landed on the Gusev Crater plains west of the Columbia Hills in January, 2004, during the Martian summer (sol 0; sol = 1 Martian day = 24 hr 40 min). Spirit explored the Columbia Hills of Gusev Crater in the vicinity of Home Plate at the onset on its second winter (sol approximately 900) until the onset of its fourth winter (sol approximately 2170). At that time, Spirit became mired in a deposit of fined-grained and sulfate-rich soil with dust-covered solar panels and unfavorable pointing of the solar arrays toward the sun. Spirit has not communicated with the Earth since sol 2210 (January, 2011). Like its twin rover Opportunity, which landed on the opposite side of Mars at Meridiani Planum, Spirit has an Alpha Particle X-Ray Spectrometer (APXS) instrument for chemical analyses and a Moessbauer spectrometer (MB) for measurement of iron redox state, mineralogical speciation, and quantitative distribution among oxidation (Fe(3+)/sigma Fe) and coordination (octahedral versus tetrahedral) states and mineralogical speciation (e.g., olivine, pyroxene, ilmenite, carbonate, and sulfate). The concentration of SO3 in Gusev rocks and soils varies from approximately 1 to approximately 34 wt%. Because the APXS instrument does not detect low atomic number elements (e.g., H and C), major-element oxide concentrations are normalized to sum to 100 wt%, i.e., contributions of H2O, CO2, NO2, etc. to the bulk composition care not considered. The majority of Gusev samples have approximately 6 plus or minus 5 wt% SO3, but there is a group of samples with high SO3 concentrations (approximately 30 wt%) and high total iron concentrations (approximately 20 wt%). There is also a group with low total Fe and SO3 concentrations that is also characterized by high SiO2 concentrations (greater than 70 wt%). The trend labeled "Basaltic Soil" is interpreted as mixtures in variable proportions between unaltered igneous material and oxidized and SO3-rich basaltic

  7. Влияние введения крысам растворов хлорида, сульфата и карбоната аммония на экскреторную и осморегулирующую функции почек при водной нагрузке (Сообщение 1. Экскреторная функция почек) = Effect of chloride, sulfate and ammonium carbonate solutions injected to rats at osmoregulation and excretory renal function at the water load (Post 1. Excretory function of the kidneys)


    Lebedeva, T. L.; Gozhenko, A. I.


    Lebedeva T. L., Gozhenko A. I. Влияние введения крысам растворов хлорида, сульфата и карбоната аммония на экскреторную и осморегулирующую функции почек при водной нагрузке (Сообщение 1. Экскреторная функция почек) = Effect of chloride, sulfate and ammonium carbonate solutions injected to rats at osmoregulation and excretory renal function at the water load (Post 1. Excretory function of the kidneys) Journal of Education, Health and Sport. 2016;6(10):557-565. eISSN 2391-8306. DOI http://dx.doi...


    Leach, Franklin E; Arungundram, Sailaja; Al-Mafraji, Kanar; Venot, Andre; Boons, Geert-Jan; Amster, I Jonathan


    Glycosaminoglycan (GAG) carbohydrates provide a challenging analytical target for structural determination due to their polydisperse nature, non-template biosynthesis, and labile sulfate modifications. The resultant structures, although heterogeneous, contain domains which indicate a sulfation pattern or code that correlates to specific function. Mass spectrometry, in particular electron detachment dissociation Fourier transform ion cyclotron resonance (EDD FT-ICR MS), provides a highly sensitive platform for GAG structural analysis by providing cross-ring cleavages for sulfation location and product ions specific to hexuronic acid stereochemistry. To investigate the effect of sulfation pattern and variations in stereochemistry on EDD spectra, a series of synthetic heparan sulfate (HS) tetrasaccharides are examined. Whereas previous studies have focused on lowly sulfated compounds (0.5-1 sulfate groups per disaccharide), the current work extends the application of EDD to more highly sulfated tetrasaccharides (1-2 sulfate groups per disaccharide) and presents the first EDD of a tetrasaccharide containing a sulfated hexuronic acid. For these more highly sulfated HS oligomers, alternative strategies are shown to be effective for extracting full structural details. These strategies inlcude sodium cation replacement of protons, for determining the sites of sulfation, and desulfation of the oligosaccharides for the generation of product ions for assigning uronic acid stereochemistry.

  9. Introduction of sulfate groups on poly(ethylene) surfaces by argon plasma immobilization of sodium alkyl sulfates

    NARCIS (Netherlands)

    Lens, J.P.; Terlingen, J.G.A.; Engbers, G.H.M.; Feijen, J.


    Sulfate groups were introduced at the surface of poly(ethylene) (PE) samples. This was accomplished by immobilizing a precoated layer of either sodium 10-undecene sulfate (S11(:)) or sodium dodecane sulfate (SDS) on the polymeric surface by means of an argon plasma treatment. For this purpose, S11(:

  10. 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

    Energy Technology Data Exchange (ETDEWEB)

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


    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.

  11. Sulfate and acid resistant concrete and mortar (United States)

    Liskowitz, John W.; Wecharatana, Methi; Jaturapitakkul, Chai; Cerkanowicz, deceased, Anthony E.


    The present invention relates to concrete, mortar and other hardenable mixtures comprising cement and fly ash for use in construction and other applications, which hardenable mixtures demonstrate significant levels of acid and sulfate resistance while maintaining acceptable compressive strength properties. The acid and sulfate hardenable mixtures of the invention containing fly ash comprise cementitious materials and a fine aggregate. The cementitous materials may comprise fly ash as well as cement. The fine aggregate may comprise fly ash as well as sand. The total amount of fly ash in the hardenable mixture ranges from about 60% to about 120% of the total amount of cement, by weight, whether the fly ash is included as a cementious material, fine aggregate, or an additive, or any combination of the foregoing. In specific examples, mortar containing 50% fly ash and 50% cement in cementitious materials demonstrated superior properties of corrosion resistance.

  12. Cholesterol sulfate in human physiology: what's it all about? (United States)

    Strott, Charles A; Higashi, Yuko


    Cholesterol sulfate is quantitatively the most important known sterol sulfate in human plasma, where it is present in a concentration that overlaps that of the other abundant circulating steroid sulfate, dehydroepiandrosterone (DHEA) sulfate. Although these sulfolipids have similar production and metabolic clearance rates, they arise from distinct sources and are metabolized by different pathways. While the function of DHEA sulfate remains an enigma, cholesterol sulfate has emerged as an important regulatory molecule. Cholesterol sulfate is a component of cell membranes where it has a stabilizing role, e.g., protecting erythrocytes from osmotic lysis and regulating sperm capacitation. It is present in platelet membranes where it supports platelet adhesion. Cholesterol sulfate can regulate the activity of serine proteases, e.g., those involved in blood clotting, fibrinolysis, and epidermal cell adhesion. As a result of its ability to regulate the activity of selective protein kinase C isoforms and modulate the specificity of phosphatidylinositol 3-kinase, cholesterol sulfate is involved in signal transduction. Cholesterol sulfate functions in keratinocyte differentiation, inducing genes that encode for key components involved in development of the barrier. The accumulating evidence demonstrating a regulatory function for cholesterol sulfate appears solid; the challenge now is to work out the molecular mechanisms whereby this interesting molecule carries out its various roles.

  13. Effects of sulfate chitosan derivatives on nonalcoholic fatty liver disease (United States)

    Yu, Mingming; Wang, Yuanhong; Jiang, Tingfu; Lv, Zhihua


    Sulfate chitosan derivatives have good solubility and therapeutic effect on the cell model of NAFLD. The aim of this study was to examine the therapeutic effect of sulfate chitosan derivatives on NAFLD. The male Wistar rats were orally fed high fat emulsion and received sulfate chitosan derivatives for 5 weeks to determine the pre-treatment effect of sulfate chitosan derivatives on NAFLD. To evaluate the therapeutic effect of sulfate chitosan derivatives on NAFLD, the rats were orally fed with high concentration emulsion for 5 weeks, followed by sulfate chitosan derivatives for 3 weeks. Histological analysis and biomedical assays showed that sulfate chitosan derivatives can dramatically prevent the development of hepatic steatosis in hepatocyte cells. In animal studies, pre-treatment and treatment with sulfate chitosan derivatives significantly protected against hepatic steatohepatitis induced by high fat diet according to histological analysis. Furthermore, increased TC, ALT, MDA, and LEP in NAFLD were significantly ameliorated by pre-treatment and treatment with sulfate chitosan derivatives. Furthermore, increased TG, AST, and TNF-α in NAFLD were significantly ameliorated by treatment with sulfate chitosan derivatives. Sulfate chitosan derivatives have good pre-treatment and therapeutic effect on NAFLD.

  14. The Importance of Heparan Sulfate in Herpesvirus Infection

    Institute of Scientific and Technical Information of China (English)

    Christopher D.O'Donnell; Deepak Shukla


    Herpes simplex virus type-1 (HSV-1) is one of many pathogens that use the cell surface glycosaminoglycan heparan sulfate as a receptor.Heparan sulfate is highly expressed on the surface and extracellular matrix of virtually all cell types making it an ideal receptor.Heparan sulfate interacts with HSV-1 envelope glycoproteins gB and gC during the initial attachment step during HSV-1 entry.In addition,a modified form of heparan sulfate,known as 3-O-sulfated heparan sulfate,interacts with HSV-1 gD to induce fusion between the viral envelope and host cell membrane.The 3-O-sulfation of heparan sulfate is a rare modification which occurs during the biosynthesis of heparan sulfate that is carded out by a family of enzymes known as 3-O-sulfotransferases.Due to its involvement in multiple steps of the infection process,heparan sulfate has been a prime target for the development of agents to inhibit HSV entry.Understanding how heparan sulfate functions during HSV-1 infection may not only be critical for inhibiting infection by this virus,but it may also be crucial in the fight against many other pathogens as well.

  15. Effects of Sulfate Chitosan Derivatives on Nonalcoholic Fatty Liver Disease

    Institute of Scientific and Technical Information of China (English)

    YU Mingming; WANG Yuanhong; JIANG Tingfu; LV Zhihua


    Sulfate chitosan derivatives have good solubility and therapeutic effect on the cell model of NAFLD. The aim of this study was to examine the therapeutic effect of sulfate chitosan derivatives on NAFLD. The male Wistar rats were orally fed high fat emulsion and received sulfate chitosan derivatives for 5 weeks to determine the pre-treatment effect of sulfate chitosan derivatives on NAFLD. To evaluate the therapeutic effect of sulfate chitosan derivatives on NAFLD, the rats were orally fed with high concentra-tion emulsion for 5 weeks, followed by sulfate chitosan derivatives for 3 weeks. Histological analysis and biomedical assays showed that sulfate chitosan derivatives can dramatically prevent the development of hepatic steatosis in hepatocyte cells. In animal studies, pre-treatment and treatment with sulfate chitosan derivatives significantly protected against hepatic steatohepatitis induced by high fat diet according to histological analysis. Furthermore, increased TC, ALT, MDA, and LEP in NAFLD were significantly amelio-rated by pre-treatment and treatment with sulfate chitosan derivatives. Furthermore, increased TG, AST, and TNF-α in NAFLD were significantly ameliorated by treatment with sulfate chitosan derivatives. Sulfate chitosan derivatives have good pre-treatment and therapeutic effect on NAFLD.


    Directory of Open Access Journals (Sweden)

    Nahidh Kaseer


    Full Text Available 31Overall crystal growth kinetics for ammonium perchlorate in laboratory scale batch  agitated vessel crystallizer have been determined from batch experiments performed in an integral mode. The effects of temperature between 30-60ºC, seed size 0.07, 0.120 and 0.275 mm and stirrer speed 160, 340, and 480 rpm, on the kinetics of crystal growth were investigated. Two different methods, viz. polynomial fitting and initial derivative were used to predict the kinetics expression. In general both methods gave comparable results for growth kinetics estimation. The order of growth process is not more than two. The activation energy for crystal growth of ammonium perchlorate was determined and found  to be equal to 5.8 kJ/ mole.            Finally, the influence of the affecting parameters on the crystal growth rate gives general expression that had an obvious dependence of the growth rate on each variables of concern (temperature, seed size, and stirrer speed .The general overall growth rate expression had shown that super saturation is the most significant variable. While the positive dependence of the stirrer speed demonstrates the importance of the diffusional step in the growth rate model. Moreover, the positive dependence of the seed size demonstrate the importance of the surface integration  step in the growth rate model. All the studied variables tend to suggest that the growth rate characteristics  of ammonium perchlorate from aqueous solution commenced in a batch crystallizer are diffusion kinetic controlled process.

  17. Engineering sulfotransferases to modify heparan sulfate

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Ding; Moon, Andrea F.; Song, Danyin; Pedersen, Lars C.; Liu, Jian (NIH); (UNC)


    The biosynthesis of heparan sulfate (HS) involves an array of specialized sulfotransferases. Here, we present a study aimed at engineering the substrate specificity of different HS 3-O-sulfotransferase isoforms. Based on the crystal structures, we identified a pair of amino acid residues responsible for selecting the substrates. Mutations of these residues altered the substrate specificities. Our results demonstrate the feasibility of tailoring the specificity of sulfotransferases to modify HS with desired functions.

  18. Fermentative hydrogen production at high sulfate concentration

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Chin-Chao [Environmental Resources Laboratory, Department of Landscape Architecture, Chungchou Institute of Technology, Changhwa 51022 (China); Chen, Hong-Pin; Wu, Jou-Hsien; Lin, Chiu-Yue [BioHydrogen Laboratory, Department of Water Resource Engineering, Feng Chia University, P.O. Box 25-123, Taichung 40724 (China)


    The hydraulic retention time (HRT) effects on fermentative hydrogen production from sucrose at high sulfate concentration of 3 g-SO{sub 4}{sup 2-}/l were studied using enriched mixed-microflora in a continuously fed reactor. The tested HRTs and organic loading rate ranged from 10 to 2 h and 48 to 240 g-COD/l-day, respectively, and the operating pH was 5.5. The experimental results indicate that hydrogen production could not be inhibited under high sulfate concentration and the efficiency was HRT-dependent with a short HRT of 4 h efficiently enhanced hydrogen production. At this HRT the biogas production rate and hydrogen gas content peaked with the hydrogen yield, hydrogen production rate and specific hydrogen production rate of 4.70 mol-H{sub 2}/mol-sucrose, 874 mmol-H{sub 2}/l-day and 432 mmol-H{sub 2}/g-VSS-day, respectively. These values were 50%, 80% and 300%, respectively, higher than those reported for 12 h HRT at the same sulfate concentration. The metabolite concentration fractions were butyrate 77.3%, acetate 15.6%, ethanol 4.4% and propionate 2.0% and changed to 55%, 27.3%, 11.2% and 6.5%, respectively, at HRT 2 h. Therefore, intimate HRT control is important to obtain efficient hydrogen production. Based on a biological growth comparison, pH 5.5 was considered to be the optimal value for operating a hydrogen-producing fermenter fed on sulfate-rich substrate. (author)

  19. Nickel hydroxide precipitation from aqueous sulfate media (United States)

    Sist, Cinziana; Demopoulos, George P.


    Hydrometallurgical processing of laterite ores constitutes a major industrial and R&D activity in extractive metallurgy. In some of the process flowsheets, nickel hydroxide precipitation is incorporated. For these operations, the optimization of nickel hydroxide precipitation is important to assure efficiency and product quality. The main objective of this investigation was to study and improve the precipitation characteristics of Ni(OH)2 in a sulfate system using supersaturation controlled precipitation.

  20. Studies on the binding of amylopectin sulfate with gastric mucin. (United States)

    Kim, Y S; Bella, A; Whitehead, J S; Isaacs, R; Remer, L


    Amylopectin sulfate, a sulfated polysaccharide that has an antipeptic property, was examined for its ability to bind gastric mucins. After chemically cross-linking the amylopectin sulfate into an insoluble gel, its binding with mucins isolated from antral and fundic mucosa of canine stomachs was studied with chromatography. A component present in both mucin fractions bound to the amylopectin sulfate gel below pH 4.5. This binding was reversible, and the complex dissociated above pH 5. Similar binding properties were found with soluble amylopectin sulfate. The component of the mucine which bound to amylopectin sulfate differed from the one which did not bind in its electrophoretic mobility and in its higher proportion of basic amino acids and a lower hexosamine, serine, and threonine content. This study suggests that amylopectin sulfate may bind to gastric mucins only under conditions of low pH.

  1. The Properties of Ammonium Dinitramine (ADN): Part 2: Melt Casting (United States)

    Hahma, A.; Edvinsson, H.; Östmark, H.


    A melt casting technique for ammonium dinitramine (ADN) and ADN/aluminum was developed. ADN proved relatively easy to cast, when 1% of magnesium oxide was used as a stabilizer and crystallization kernels. Densities of ADN/MgO 99/1 were 92 to 97% of theoretical mean density (TMD) and those of ADN/Al/MgO 64/35/1 were between 95 and 99% of TMD. Sedimentation of Al in the melt was prevented and the particle wetting was ensured by selecting a suitable particle size for Al. No gelling agents or other additives were used. The casting process and factors influencing it are discussed.

  2. Surge ammonium uptake in macroalgae from a coral atoll

    Digital Repository Service at National Institute of Oceanography (India)

    Raikar, V.; Wafar, M.V.M.

    Maintenance of high levels of biological productivity (up to several gC m-2 d-1) (Crossland et al., 1991) by coral atolls in oligotrophic oceanic waters with low ambient concentrations of N nutrients (typically of the order of few hundreds of nmols..., fish shoals migrating onto the reef could raise ambient ammonium concentrations in the vicinity of corals up to 0.9 ? M (Meyer et al., 1983) and area-specific N regeneration by actively feeding holothurians (Uthicke and Klumpp, 1998) could be in a...

  3. Further laboratory and theoretical investigations of ammonium dinitramide

    Energy Technology Data Exchange (ETDEWEB)

    Tulis, A.J.; Snelson, A. [IIT Research Institut, Chicago (United States); Heberlein, C.; Patel, D.L. [U.S. Army Cecom RD et E Center, NVESD (United States)


    Hydrogen and deuterated ammonium dinitramide have been vaporized under high vacuum and the IR matrix isolation spectra of the decomposition products obtained. Tentative vibration assignments have been made for HN(NO{sub 2}){sub 2} and DN(NO{sub 2}){sub 2} assuming a symmetrical non-planar structure in which the H or D is bonded to the central nitrogen atom. Other structures are also possible. Ab initio calculations have been made for the various structural isomers of hydrogen dinitramide. Vibration frequencies calculated for the hydrogenated and deuterated species are compared with the experimental values with the object of identifying the molecules` structure. (authors) 3 refs.

  4. Experimental study of the detonation of technical grade ammonium nitrate (United States)

    Presles, Henri-Noël; Vidal, Pierre; Khasainov, Boris


    The detonation of technical grade ammonium nitrate at the density ρ=0.666 g/cm confined in PVC and steel tubes was experimentally studied. The results show that the detonation is self-sustained and steady in steel tubes with diameter as small as 12 mm. Critical detonation diameter lies between 8 and 12 mm in 2 mm thick steel tubes and between 55 and 81 mm in PVC tubes. These values testify a strong detonation sensitivity of this product. To cite this article: H.-N. Presles et al., C. R. Mecanique 337 (2009).

  5. Ammonium diamminesilver(I bis(5-chloro-2-hydroxybenzenesulfonate trihydrate

    Directory of Open Access Journals (Sweden)

    Zhao-Peng Deng


    Full Text Available The reaction of silver nitrate with 5-chloro-2-hydroxybenzenesulfonic acid in the presence of ammonia yielded the title salt, (NH4[Ag(NH32](C6H4ClO4S2·3H2O. The AgI ion shows linear coordination [N—Ag—N = 175.2 (1 °]. The ammonium and diamminesilver cations, the benzenesulfonate anion and the lattice water molecules interact through an intricate network of N—H...O and O—H...O hydrogen bonds to form a three-dimensional network.

  6. Sulfation and Cation Effects on the Conformational Properties of the Glycan Backbone of Chondroitin Sulfate Disaccharides (United States)

    Faller, Christina E.; Guvench, Olgun


    Chondroitin sulfate (CS) is one of several glycosaminoglycans that are major components of proteoglycans. A linear polymer consisting of repeats of the disaccharide -4GlcAβ1-3GalNAcβ1-, CS undergoes differential sulfation resulting in five unique sulfation patterns. Because of the dimer repeat, the CS glycosidic “backbone” has two distinct sets of conformational degrees of freedom defined by pairs of dihedral angles: (ϕ1, ψ1) about the β1-3 glycosidic linkage and (ϕ2, ψ2) about the β1-4 glycosidic linkage. Differential sulfation and the possibility of cation binding, combined with the conformational flexibility and biological diversity of CS, complicate experimental efforts to understand CS three-dimensional structures at atomic resolution. Therefore, all-atom explicit-solvent molecular dynamics simulations with Adaptive Biasing Force sampling of the CS backbone were applied to obtain high resolution, high precision free energies of CS disaccharides as a function of all possible backbone geometries. All ten disaccharides (β1-3 vs. β1-4 linkage x five different sulfation patterns) were studied; additionally, ion effects were investigated by considering each disaccharide in the presence of either neutralizing sodium or calcium cations. GlcAβ1-3GalNAc disaccharides have a single, broad, thermodynamically important free-energy minimum whereas GalNAcβ1-4GlcA disaccharides have two such minima. Calcium cations but not sodium cations bind to the disaccharides, and binding is primarily to the GlcA –COO− moiety as opposed to sulfate groups. This binding alters the glycan backbone thermodynamics in instances where a calcium cation bound to –COO− can act to bridge and stabilize an interaction with an adjacent sulfate group, whereas, in the absence of this cation, the proximity of a sulfate group to –COO− results in two like charges being both desolvated and placed adjacent to each other and is found to be destabilizing. In addition to providing

  7. Conformation of sulfated galactan and sulfated fucan in aqueous solutions: implications to their anticoagulant activities. (United States)

    Becker, Camila F; Guimarães, Jorge A; Mourão, Paulo A S; Verli, Hugo


    The discovery of sulfated galactans and sulfated fucans in marine invertebrates with simple and ordered structures opened new perspectives to investigate the biological activity of these molecules and to determine whether different structures confer high affinity for a particular protein. We undertook a conformational analysis of a 2-sulfated, 3-linked alpha-L-galactan and of a alpha-L-fucan with similar structure. Through comparison between theoretical and NMR derived coupling constants, we observed that the pyranose rings are predominantly in the (1)C(4) conformation in these polysaccharides. Additionally, the geometry of the glycosidic linkages was determined based on force field calculations, indicating that the two polysaccharides have similar conformations in solution. Since the sulfated alpha-L-galactan, but not the alpha-L-fucan potentiates antithrombin (AT) inhibition of thrombin, the solution conformations of the compounds were docked into AT and the complexes obtained were refined through molecular dynamics calculations. The obtained results indicates extremely different orientations for the two polysaccharides, which well correlates and explain their distinct anticoagulant activities. Finally, the molecular mechanism of a selective 2-desulfation reaction, observed among sulfated fucans, was explained as a consequence of an intramolecular hydrogen bond capable of assisting in the removal of the charged group.

  8. Biological removal of selenate and ammonium by activated sludge in a sequencing batch reactor. (United States)

    Mal, J; Nancharaiah, Y V; van Hullebusch, E D; Lens, P N L


    Wastewaters contaminated by both selenium and ammonium need to be treated prior to discharge into natural water bodies, but there are no studies on the simultaneous removal of selenium and ammonium. A sequencing batch reactor (SBR) was inoculated with activated sludge and operated for 90days. The highest ammonium removal efficiency achieved was 98%, while the total nitrogen removal was 75%. Nearly a complete chemical oxygen demand removal efficiency was attained after 16days of operation, whereas complete selenate removal was achieved only after 66days. The highest total Se removal efficiency was 97%. Batch experiments showed that the total Se in the aqueous phase decreased by 21% with increasing initial ammonium concentration from 50 to 100mgL(-1). This study showed that SBR can remove both selenate and ammonium via, respectively, bioreduction and partial nitrification-denitrification and thus offer possibilities for treating selenium and ammonium contaminated effluents.

  9. Effects of Calcium Lignosulfonate and Silicic Acid on Ammonium Nitrate Degradation

    Directory of Open Access Journals (Sweden)

    Ahmet Ozan Gezerman


    Full Text Available Ammonium nitrate salts are the most commonly used nitrogenous fertilizers in industry. However, storage of ammonium nitrate is problematic, since its initial properties can decline because of environmental factors, leading to large economic losses. In this study, in order to prevent the caking and degradation of ammonium nitrate, an alternative composition with additional calcium lignosulfonate and silicic acid was studied. The resulting fertilizer was analyzed by screening analysis, ion chromatography, and electron microscopy methods.

  10. Shock Initiation and Equation of State of Ammonium Nitrate (United States)

    Robbins, David; Sheffield, Steve; Dattelbaum, Dana; Chellappa, Raja; Velisavljevic, Nenad


    Ammonium nitrate (AN) is a widely used fertilizer and mining explosive commonly found in ammonium nitrate-fuel oil. Neat AN is a non-ideal explosive with measured detonation velocities approaching 4 km/s. Previously, we reported a thermodynamically-complete equation of state for AN based on its maximum density, and showed that near-full density AN did not initiate when subjected to shock input conditions up to 22 GPa. In this work, we extend these initial results, by presenting new Hugoniot data for intermediate density neat AN obtained from gas gun-driven plate impact experiments. AN at densities from 1.8 to 1.5 g/cm3 were impacted into LiF windows using a two-stage light gas gun. Dual VISARs were used to measure the interfacial particle velocity wave profile as a function of time following impact. The new Hugoniot data, in addition to updates to thermodynamic parameters derived from structural analysis and vibrational spectroscopy measurements in high pressure diamond anvil cell experiments, are used to refine the unreacted EOS for AN. Furthermore, shock initiation of neat AN was observed as the initial porosity increased (density decreased). Insights into the relationship(s) between initial density and shock initiation sensitivity are also presented, from evidence of shock initiation in the particle velocity profiles obtained for the lower density AN samples.

  11. Removal of vanadium from ammonium molybdate solution by ion exchange

    Institute of Scientific and Technical Information of China (English)

    LI Qing-gang; ZHANG Qi-xiu; ZENG Li; XIAO Lian-sheng; YANG Ya-nan


    The separation techniques of vanadium and molybdenum were summarized, and a new method of removal V(Ⅴ) from Mo(Ⅵ) by adsorption with chelate resin was presented. Nine kinds of chelate resins were used to investigate the adsorbent capability of V(Ⅴ) in ammonium molybdate solution with static method. The test results show that DDAS, CUW and CW-2 resins can easily adsorb V(Ⅴ) in ammonium molybdate solution, but hardly adsorb Mo(Ⅵ). The dynamic experimental results show more than 99.5% of V(Ⅴ) can be adsorbed, and the adsorption rate of Mo(Ⅵ) is less than 0.27% at 294-296 K for 60 min at pH 7.42-8.02. The mass ratio of V to Mo decreases to l/5 0000 in the effluent from 1/255 in the initial solution. The loaded resin can be desorbed by 5% NH3·H2O solution, and the vanadium desorption rate can reach 99.6%. The max concentration of vanadium in desorbed solution can reach 20 g/L, while the concentration of molybdenum is less than 0.8 g/L.

  12. Regulation by ammonium of glutamate dehydrogenase (NADP+) from Saccharomyces cerevisiae. (United States)

    Bogonez, E; Satrústegui, J; Machado, A


    The activity of glutamate dehydrogenase (NADP+) (EC; NADP-GDH) of Saccharomyces cerevisiae is decreased under conditions in which intracellular ammonia concentrations increases. A high internal ammonia concentration can be obtained (a) by increasing the ammonium sulphate concentration in the culture medium, and (b) by growing the yeast either in acetate + ammonia media, where the pH of the medium rises during growth, or in heavily buffered glucose + ammonia media at pH 7.5. Under these conditions cellular oxoglutarate concentrations do not vary and changes in NADP-GDH activity appear to provide a constant rate of oxoglutarate utilization. The following results suggest that the decrease in NADP-GDH activity in ammonia-accumulating yeast cells is brought about by repression of synthesis: (i) after a shift to high ammonium sulphate concentrations, the number of units of activity per cell decreased as the inverse of cell doubling; and (ii) the rate of degradation of labelled NADP-GDH was essentially the same in ammonia-accumulating yeast cells and in controls, whereas the synthesis constant was much lower in the ammonia-accumulating cells than in the controls.

  13. Fabrication and cytocompatibility of spherical magnesium ammonium phosphate granules. (United States)

    Christel, Theresa; Geffers, Martha; Klammert, Uwe; Nies, Berthold; Höß, Andreas; Groll, Jürgen; Kübler, Alexander C; Gbureck, Uwe


    Magnesium phosphate compounds, as for example struvite (MgNH4PO4·6H2O), have comparable characteristics to calcium phosphate bone substitutes, but degrade faster under physiological conditions. In the present work, we used a struvite forming calcium doped magnesium phosphate cement with the formulation Ca0.75Mg2.25(PO4)2 and an ammonium phosphate containing aqueous solution to produce round-shaped granules. For the fabrication of spherical granules, the cement paste was dispersed in a lipophilic liquid and stabilized by surfactants. The granules were characterized with respect to morphology, size distribution, phase composition, compressive strength, biocompatibility and solubility. In general, it was seen that small granules can hardly be produced by means of emulsification, when the raw material is a hydraulic paste, because long setting times promote coalescence of initially small unhardened cement droplets. Here, this problem was solved by using an aqueous solution containing both the secondary (NH4)2HPO4 and primary ammonium phosphates NH4H2PO4 to accelerate the setting reaction. This resulted in granules with 97 wt.% having a size in the range between 200 and 1,000 μm. The novel solution composition doubled the compressive strength of the cement to 37 ± 5 MPa without affecting either the conversion to struvite or the cytocompatibility using human fetal osteoblasts.

  14. Development of electrochemical denitrification from waste water containing ammonium nitrate

    Energy Technology Data Exchange (ETDEWEB)

    Sawa, Toshio; Hirose, Yasuo; Ishii, Yoshinori; Takatsudo, Atsushi; Wakasugi, Kazuhico; Hayashi, Hiroshi


    The authors developed processes to dentrify waste water containing ammonium nitrate discharged from the nuclear fuel manufacturing works and to recover nitric acid and ammonia. For denitrification they applied the operating method and the conditions of operation to make 0.4mM or less from NH{sub 4}NO{sub 3} waste water of 1.5 M by 3 stages of electrodialysis cells. To recover nitric acid and ammonium water, they separated HNO{sub 3} solution of 6 M and NH{sub 4}OH solution with one unit of electrolysis cell, then absorbed NH{sub 3} gas from NH{sub 4}OH solution with water and applied the condition of operation to recover 8 M NH{sub 4}OH solution. The authors demonstrated that treatment and recovery can be carried out stably with actual waste water with a system through the combination of previously mentioned electrodialysis cells, electrolysis cells and an ammonia gas absorber. At present they are planning a plant where NH{sub 4}NO{sub 3} waste water of 4,500 mol can be treated per day.

  15. Heritability and clinical determinants of serum indoxyl sulfate and p-cresyl sulfate, candidate biomarkers of the human microbiome enterotype.

    Directory of Open Access Journals (Sweden)

    Liesbeth Viaene

    Full Text Available BACKGROUND: Indoxyl sulfate and p-cresyl sulfate are unique microbial co-metabolites. Both co-metabolites have been involved in the pathogenesis of accelerated cardiovascular disease and renal disease progression. Available evidence suggests that indoxyl sulfate and p-cresyl sulfate may be considered candidate biomarkers of the human enterotype and may help to explain the link between diet and cardiovascular disease burden. OBJECTIVE AND DESIGN: Information on clinical determinants and heritability of indoxyl sulfate and p-cresyl sulfate serum is non-existing. To clarify this issue, the authors determined serum levels of indoxyl sulfate and p-cresyl sulfate in 773 individuals, recruited in the frame of the Flemish Study on Environment, Genes and Health Outcomes (FLEMENGHO study. RESULTS: Serum levels of indoxyl sulfate and p-cresyl sulfate amounted to 3.1 (2.4-4.3 and 13.0 (7.4-21.5 μM, respectively. Regression analysis identified renal function, age and sex as independent determinants of both co-metabolites. Both serum indoxyl sulfate (h2 = 0.17 and p-cresyl sulfate (h2 = 0.18 concentrations showed moderate but significant heritability after adjustment for covariables, with significant genetic and environmental correlations for both co-metabolites. LIMITATIONS: Family studies cannot provide conclusive evidence for a genetic contribution, as confounding by shared environmental effects can never be excluded. CONCLUSIONS: The heritability of indoxyl sulfate and p-cresyl sulfate is moderate. Besides genetic host factors and environmental factors, also renal function, sex and age influence the serum levels of these co-metabolites.

  16. Studies on Biquaternary Ammonium Salt Algaecide for Removing Red Tide Algae

    Institute of Scientific and Technical Information of China (English)

    刘洁生; 张珩; 杨维东; 高洁; 柯琼


    The paper deals with the removal and control of red tide algae, Phaeoecystis globosa and Alexandrium tamarense by biquaternary ammonium salt algaecide. The results show that the efficient concentration of biquaternary ammonium salt to control the two algaes in 96 h is 0.8 mg · L-1 and 0.4 mg · L-1, respectively. It is found that biquaternary ammonium salt has high efficiency and longer duration of action in the removal and control of algae.Biquaternary ammonium salt might be an excellent algaecide to control HAB.

  17. Highly efficient hydrogen storage system based on ammonium bicarbonate/formate redox equilibrium over palladium nanocatalysts. (United States)

    Su, Ji; Yang, Lisha; Lu, Mi; Lin, Hongfei


    A highly efficient, reversible hydrogen storage-evolution process has been developed based on the ammonium bicarbonate/formate redox equilibrium over the same carbon-supported palladium nanocatalyst. This heterogeneously catalyzed hydrogen storage system is comparable to the counterpart homogeneous systems and has shown fast reaction kinetics of both the hydrogenation of ammonium bicarbonate and the dehydrogenation of ammonium formate under mild operating conditions. By adjusting temperature and pressure, the extent of hydrogen storage and evolution can be well controlled in the same catalytic system. Moreover, the hydrogen storage system based on aqueous-phase ammonium formate is advantageous owing to its high volumetric energy density.

  18. Sulfation pattern of fucose branches affects the anti-hyperlipidemic activities of fucosylated chondroitin sulfate. (United States)

    Wu, Nian; Zhang, Yu; Ye, Xingqian; Hu, Yaqin; Ding, Tian; Chen, Shiguo


    Fucosylated chondroitin sulfates (fCSs) are glycosaminoglycans extracted from sea cucumbers, consisting of chondroitin sulfate E (CSE) backbones and sulfated fucose branches. The biological properties of fCSs could be affected by the sulfation pattern of their fucose branches. In the present study, two fCSs were isolated from sea cucumbers Isostichopus badionotus (fCS-Ib) and Pearsonothuria graeffei (fCS-Pg). Their monosaccharide compositions of glucuronic acid (GlcA), N-acetylgalactosamine (GalNAc), fucose (Fuc) and sulfate were at similar molar ratio with 1.0/0.7/0.9/3.1 for fCS-Ib and 1.0/0.8/1.5/2.6 for fCS-Pg. The two fCSs have different sulfation patterns on their fucose branches, fCS-Pg with 3,4-O-disulfation while fCS-Ib with 2,4-O-disulfation. Their antihyperlipidemic effects were compared using a high-fat high-fructose diet (HFFD)-fed C57BL/6J mice model. Both fCS-Ib and fCS-Pg had significant effects on lipid profile improvement, liver protection, blood glucose diminution and hepatic glycogen synthesis. Specifically, fCS-Pg with 3,4-O-disulfation fucose branches was more effective in reduction of blood cholesterol (TC), low density lipoprotein (LDL) and atherogenic index (AI). Our results indicate that both fCSs, especially fCS-Pg, could be used as a potential anti-hyperlipidemic drug.

  19. Purity determination of amphotericin B, colistin sulfate and tobramycin sulfate in a hydrophilic suspension by HPLC. (United States)

    Pfeifer, Corina; Fassauer, Georg; Gerecke, Hagen; Jira, Thomas; Remane, Yvonne; Frontini, Roberto; Byrne, Jonathan; Reinhardt, Robert


    A suspension comprising of the three antibiotic substances amphotericin B, colistin sulfate and tobramycin sulfate is often used in clinical practice for the selective decontamination of the digestive tract of patients in intensive care. Since no detailed procedures, specifications or stability data are available for manufacturing this suspension, there may be discrepancies regarding formulation and stability of suspensions prepared in different pharmacies. The aim of this work is to develop a standardized formulation and to determine its stability under defined storage conditions. This would help guarantee that all patients receive the same preparation, therefore ensuring similar efficacy and improved safety. The first step in this process is to develop the required analytical tools to measure the content and purity of the drug substances in this complex mixture. In this paper, the development and validation of these tools as well as the development of the drug suspension formulation is described. The formulation comprises of Ampho-Moronal(®)-Suspension (Dermapharm) and a buffered, preservated aqueous solution of colistin sulfate and tobramycin sulfate. Two simple, well established high-performance liquid chromatography (HPLC) methods in the European Pharmacopoeia (EP) for impurity profiling of the two active ingredients amphotericin B and colistin sulfate were combined with a newly developed sample extraction procedure for the suspension. Sufficient selectivity and stability-indicating power have been demonstrated. Additionally, a new robust routine method was developed to determine possible degradation products of tobramycin sulfate in the investigated suspension. The specificity, precision, accuracy and linearity of the analytical procedures were demonstrated. The recovery rate was in the range of 90-110%. The precision results for the calculated impurities showed variation coefficients of <10%. The calibration curves were found to be linear with correlation

  20. The preparation and antioxidant activity of glucosamine sulfate (United States)

    Xing, Ronge; Liu, Song; Wang, Lin; Cai, Shengbao; Yu, Huahua; Feng, Jinhua; Li, Pengcheng


    Glucosamine sulfate was prepared from glucosamine hydrochloride that was produced by acidic hydrolysis of chitin by ion-exchange method. Optical rotation and elemental analysis characterized the degree of its purity. In addition, the antioxidant potency of chitosan derivative-glucosamine sulfate was investigated in various established in vitro systems, such as superoxide (O{2/-})/hydroxyl (·OH) radicals scavenging, reducing power, iron ion chelating. The following results are obtained: first, glucosamine sulfate had pronounced scavenging effect on superoxide radical. For example the O{2/-} scavenging activity of glucosamine sulfate was 92.11% at 0.8 mg/mL. Second, the ·OH scavenging activity of glucosamine sulfate was also strong, and was about 50% at 3.2 mg/mL. Third, the reducing power of glucosamine sulfate was more pronounced. The reducing power of glucosamine sulfate was 0.643 at 0.75 mg/mL. However, its potency for ferrous ion chelating was weak. Furthermore, except for ferrous ion chelating potency, the scavenging rate of radical and reducing power of glucosamine sulfate were concentration-dependent and increased with their increasing concentrations, but its ferrous ion chelating potency decreased with the increasing concentration. The multiple antioxidant activities of glucosamine sulfate were evidents of reducing power and superoxide/hydroxyl radicals scavenging ability. These in vitro results suggest the possibility that glucosamine sulfate could be used effectively as an ingredient in health or functional food, to alleviate oxidative stress.

  1. The preparation and antioxidant activity of glucosamine sulfate

    Institute of Scientific and Technical Information of China (English)

    XING Ronge; LIU Song; WANG Lin; CAI Shengbao; YU Huahua; FENG Jinhua; LI Pengcheng


    Glucosamine sulfate was prepared from glucosamine hydrochloride that was produced by acidic hydrolysis of chitin by ion-exchange method. Optical rotation and elemental analysis characterized the degree of its purity. In addition, the antioxidant potency of chitosan derivative-glucosamine sulfate was investigated in various established in vitro systems, such as superoxide (O(2))/hydroxyl (·OH) radicals scavenging, reducing power, iron ion chelating. The following results are obtained: first, glucosamine sulfate had pronounced scavenging effect on superoxide radical. For example the O(2) scavenging activity of glucosamine sulfate was 92.11% at 0.8 mg/mL. Second, the ·OH scavenging activity of glucosamine sulfate was also strong, and was about 50% at 3.2 mg/mL Third, the reducing power of glucosamine sulfate was more pronounced. The reducing power of glucosamine sulfate was 0.643 at 0.75 mg/mL.However, its potency for ferrous ion chelating was weak. Furthermore, except for ferrous ion chelating potency, the scavenging rate of radical and reducing power of glucosamine sulfate were concentration-dependent and increased with their increasing concentrations, but its ferrous ion chelating potency decreased with the increasing concentration. The multiple antioxidant activities of glucosamine sulfate were evidents of reducing power and superoxide/hydroxyl radicals scavenging ability. These in vitro results suggest the possibility that glucosamine sulfate could be used effectively as an ingredient in health or functional food, to alleviate oxidative stress.

  2. Inactivation of thrombin by a fucosylated chondroitin sulfate from echinoderm. (United States)

    Mourão, P A; Boisson-Vidal, C; Tapon-Bretaudière, J; Drouet, B; Bros, A; Fischer, A


    A polysaccharide extracted from the sea cucumber body wall has the same backbone structure as the mammalian chondroitin sulfate, but some of the glucuronic acid residues display sulfated fucose branches. These branches confer high anticoagulant activity to the polysaccharide. Since the sea cucumber chondroitin sulfate has analogy in structure with mammalian glycosaminoglycans and sulfated fucans from brown algae, we compared its anticoagulant action with that of heparin and of a homopolymeric sulfated fucan with approximately the same level of sulfation as the sulfated fucose branches found in the sea cucumber polysaccharide. These various compounds differ not only in their anticoagulant potencies but also in the mechanisms of thrombin inhibition. Fucosylated chondroitin sulfate, like heparin, requires antithrombin or heparin cofactor II for thrombin inhibition. Sulfated fucans from brown algae have an antithrombin effect mediated by antithrombin and heparin cofactor II, plus a direct antithrombin effect more pronounced for some fractions. But even in the case of these two polysaccharides, we observed some differences. In contrast with heparin, total inhibition of thrombin in the presence of antithrombin is not achieved with fucosylated chondroitin sulfate, possibly reflecting a less specific interaction. Fucosylated chondroitin sulfate is able to inhibit thrombin generation after stimulation by both contact-activated and thromboplastin-activated systems. It delayed only the contact-induced thrombin generation, as expected for an anticoagulant without direct thrombin inhibition. Overall, the specific spatial array of the sulfated fucose branches in the fucosylated chondroitin sulfate not only confer high anticoagulant activity to the polysaccharide but also determine differences in the way it inhibits thrombin.

  3. Lacrimal gland development and Fgf10-Fgfr2b signaling are controlled by 2-O- and 6-O-sulfated heparan sulfate

    NARCIS (Netherlands)

    Qu, X.; Carbe, C.; Tao, C.; Powers, A.; Lawrence, R.; Kuppevelt, A.H.M.S.M. van; Cardoso, W.V.; Grobe, K.; Esko, J.D.; Zhang, X.


    Heparan sulfate, an extensively sulfated glycosaminoglycan abundant on cell surface proteoglycans, regulates intercellular signaling through its binding to various growth factors and receptors. In the lacrimal gland, branching morphogenesis depends on the interaction of heparan sulfate with Fgf10-Fg


    Directory of Open Access Journals (Sweden)

    Akhmad Mustafa


    growth of seaweed in acid sulfate soil-affected ponds of Angkona Sub-district East Luwu Regency South Sulawesi Province. Cultivation of seaweed was done for six weeks in 30 selected brackishwater ponds. Seeds of seaweed with weight of 100 g were stocked in hapa sized 1.0 m x 1.0 m x 1.2 m. Dependent variable that was observed was specific growth rate, whereas independent variables were water quality variables including light intensity, salinity, temperature, pH, carbondioxide, nitrate, ammonium, phosphate, and iron. Analyses of multiple regressions were used to determine the independent variables which could be used to predict the dependent variable. Research result indicated that relative growth rate of seaweed in acid sulfate soils-affected brackishwater ponds ranged from 1.52% to 3.63%/day with 2.88% ± 0.56%/day in average. Among nine observed water quality variables, only five variables namely: nitrate, salinity, ammonium, phosphate and iron influence significantly on the growth of seaweed in acid sulfate soils-affected brackishwater ponds. The growth of seaweed in acid sulfate soils-affected brackishwater ponds of Angkona District East Luwu Regency, can be improved by using nitrogen-based fertilizers to increase ammonium and nitrate contents and also fertilizers which contain phosphorus to improve phosphate content to a certain level. Pond remediation to decrease iron content and also rearing seaweed at higher salinity (but less than 30 ppt can also be alternatives to increase the growth of seaweed.

  5. Effects of sulfate deprivation on the production of chondroitin/dermatan sulfate by cultures of skin fibroblasts from normal and diabetic individuals

    Energy Technology Data Exchange (ETDEWEB)

    Silbert, C.K.; Humphries, D.E.; Palmer, M.E.; Silbert, J.E. (Veterans Administration Outpatient Clinic, Boston, MA (USA))


    Human skin fibroblast monolayer cultures from two normal men, three Type I diabetic men, and one Type I diabetic woman were incubated with (3H)glucosamine in the presence of diminished concentrations of sulfate. Although total synthesis of (3H)chondroitin/dermatan glycosaminoglycans varied somewhat between cell lines, glycosaminoglycan production was not affected within any line when sulfate levels were decreased from 0.3 mM to 0.06 mM to 0.01 mM to 0 added sulfate. Lowering of sulfate concentrations resulted in diminished sulfation of chondroitin/dermatan in a progressive manner, so that overall sulfation dropped to as low as 19% for one of the lines. Sulfation of chondroitin to form chondroitin 4-sulfate and chondroitin 6-sulfate was progressively and equally affected by decreasing the sulfate concentration in the culture medium. However, sulfation to form dermatan sulfate was preserved to a greater degree, so that the relative proportion of dermatan sulfate to chondroitin sulfate increased. Essentially all the nonsulfated residues were susceptible to chondroitin AC lyase, indicating that little epimerization of glucuronic acid residues to iduronic acid had occurred in the absence of sulfation. These results confirm the previously described dependency of glucuronic/iduronic epimerization on sulfation, and indicate that sulfation of the iduronic acid-containing disaccharide residues of dermatan can take place with sulfate concentrations lower than those needed for 6-sulfation and 4-sulfation of the glucuronic acid-containing disaccharide residues of chondroitin. There were considerable differences among the six fibroblast lines in susceptibility to low sulfate medium and in the proportion of chondroitin 6-sulfate, chondroitin 4-sulfate, and dermatan sulfate. However, there was no pattern of differences between normals and diabetics.

  6. Sulfated fucan as support for antibiotic immobilization. (United States)

    Araújo, P M; Oliveira, G B; Córdula, C R; Leite, E L; Carvalho Jr, L B; Silva, M P C


    Xylofucoglucuronan from Spatoglossum schröederi algae was tested as a support for antibiotic immobilization. The polysaccharide (20 mg in 6 ml) was first activated using carbodiimide, 1-ethyl-3-(3-dimethylamino-propyl)carbodiimide methiodide (20 mg in 2 ml), under stirring for 1 h at 25 masculine C and pH from 4.5 to 5.0. After adjusting the pH to 8.0, either gentamicin or amikacin (62.5 mg in 1.25 ml) was then immobilized on this chemically modified polysaccharide with shaking for 24 h in a cold room. Infrared spectra of the activated carbodiimide xylofucoglucuronan showed two bands to carbonyl (C=O at 1647.9 and 1700.7 cm(-1)) and to amide (C-NH2) groups (1662.8 and 1714.0 cm(-1)). Microbial characterization of the derivatives was carried out by the disk diffusion method using Staphylococcus aureus or Klebsiella pneumoniae incorporated in Müller Hinton medium. Inhibition halos of bacterial growth were observed for the antibiotics immobilized on this sulfated heteropolysaccharide before and after dialysis. However, the halos resulting from the samples after dialysis were much smaller, suggesting that dialysis removed either non-covalently bound antibiotic or other small molecules. In contrast, bacterial growth was not inhibited by either xylofucoglucuronan or its activated form or by gentamicin or amikacin after dialysis. An additional experiment was carried out which demonstrated that the sulfated heteropolysaccharide was hydrolyzed by the microorganism. Therefore, the antibiotic immobilized on xylofucoglucuronan can be proposed as a controlled drug delivery system. Furthermore, this sulfated heteropolysaccharide can be extracted easily from sea algae Spatoglossum schröederi.

  7. Sulfated fucan as support for antibiotic immobilization

    Directory of Open Access Journals (Sweden)

    Araújo P.M.


    Full Text Available Xylofucoglucuronan from Spatoglossum schröederi algae was tested as a support for antibiotic immobilization. The polysaccharide (20 mg in 6 ml was first activated using carbodiimide, 1-ethyl-3-(3-dimethylamino-propylcarbodiimide methiodide (20 mg in 2 ml, under stirring for 1 h at 25ºC and pH from 4.5 to 5.0. After adjusting the pH to 8.0, either gentamicin or amikacin (62.5 mg in 1.25 ml was then immobilized on this chemically modified polysaccharide with shaking for 24 h in a cold room. Infrared spectra of the activated carbodiimide xylofucoglucuronan showed two bands to carbonyl (C = O at 1647.9 and 1700.7 cm-1 and to amide (CÝ-NH2 groups (1662.8 and 1714.0 cm-1. Microbial characterization of the derivatives was carried out by the disk diffusion method using Staphylococcus aureus or Klebsiella pneumoniae incorporated in Müller Hinton medium. Inhibition halos of bacterial growth were observed for the antibiotics immobilized on this sulfated heteropolysaccharide before and after dialysis. However, the halos resulting from the samples after dialysis were much smaller, suggesting that dialysis removed either non-covalently bound antibiotic or other small molecules. In contrast, bacterial growth was not inhibited by either xylofucoglucuronan or its activated form or by gentamicin or amikacin after dialysis. An additional experiment was carried out which demonstrated that the sulfated heteropolysaccharide was hydrolyzed by the microorganism. Therefore, the antibiotic immobilized on xylofucoglucuronan can be proposed as a controlled drug delivery system. Furthermore, this sulfated heteropolysaccharide can be extracted easily from sea algae Spatoglossum schröederi.

  8. Controlling sulfate reducing bacteria by slug dosing with quick-kill antimicrobials and by continuous dosing with isothiazolones

    Energy Technology Data Exchange (ETDEWEB)

    Haack, T.K.; Greenley, D.E.


    This patent describes a process for controlling biological contamination of oil production water injection systems by sulfate-reducing sessile bacteria wherein a slug dose of a quick-kill antimicrobial selected from one or more of the group consisting of (C{sub 3}-C{sub 7}) alkanedials, formaldehyde, cationic polymeric biguanides, quaternary ammonium compounds (alkyldimethylbenzylammonium chlorides), quarternary phosphodium compounds, phenolics, cocodiamine, 2-bromo-2-nitropropanediol, acrolein, dibromonitrilopropionamide and organic thiocyanates is applied to the injection water, the improvement comprising substantially continuously dosing the injection water at a concentration of about 0.25 to 5 ppm based on the weight of injection water with a maintenance antimicrobial selected from the group consisting of an isothiazolone.

  9. Synthesis and characterization of novel cellulose ether sulfates. (United States)

    Rohowsky, Juta; Heise, Katja; Fischer, Steffen; Hettrich, Kay


    The synthesis and characterization of novel cellulose sulfate derivatives was reported. Various cellulose ethers were prepared in a homogeneous reaction with common sulfating agents. The received product possess different properties in dependence on the reaction conditions like sulfating agent, solvent, reaction time and reaction temperature. The cellulose ether sulfates are all soluble in water, they rheological behavior could be determined by viscosity measurements and the determination of the sulfur content by elemental analysis lead to a resulting degree of substitution ascribed to sulfate groups (DSSul) of the product. A wide range of products from DSSul 0.1 to DSSul 2.7 will be obtained. Furthermore the cellulose sulfate ethers could be characterized by Raman spectroscopy.

  10. Chemical leukoderma induced by dimethyl sulfate* (United States)

    Gozali, Maya Valeska; Zhang, Jia-an; Yi, Fei; Zhou, Bing-rong; Luo, Dan


    Chemical leukoderma occurs due to the toxic effect of a variety of chemical agents. Mechanisms include either destruction or inhibition of melanocytes. We report two male patients (36 and 51 years old) who presented with multiple hypopigmented macules and patches on the neck, wrist, and legs after exposure to dimethyl sulfate in a chemical industry. Physical examination revealed irregular depigmentation macules with sharp edges and clear hyperpigmentation around the lesions. History of repeated exposure to a chemical agent can help the clinical diagnosis of chemical leukoderma. This diagnosis is very important for prognosis and therapeutic management of the disease.

  11. New Bioactive Alkyl Sulfates from Mediterranean Tunicates

    Directory of Open Access Journals (Sweden)

    Marialuisa Menna


    Full Text Available Chemical investigation of two species of marine ascidians, Aplidium elegans and Ciona edwardsii, collected in Mediterranean area, led to isolation of a series of alkyl sulfates (compounds 1–5 including three new molecules 1–3. Structures of the new metabolites have been elucidated by spectroscopic analysis. Based on previously reported cytotoxic activity of these type of molecules, compounds 1–3 have been tested for their effects on the growth of two cell lines, J774A.1 (BALB/c murine macrophages and C6 (rat glioma in vitro. Compounds 1 and 2 induced selective concentration-dependent mortality on J774A.1 cells.

  12. Quantitative remote sensing of ammonium minerals, Cedar Mountains, Esmeralda County, Nevada (United States)

    Baugh, William M.; Kruse, Fred A.


    Mineral-bound ammonium (NH4+) was discovered by the U.S. Geological Survey in the southern Cedar Mountains of Esmeralda County, Nevada in 1989. At 10 km in length, this site is 100 times larger than any previously known occurrence in volcanic rocks. The ammonium occurs in two hydrothermally altered, crystal-rich rhyolitic tuff units of Oligocene age, and is both structurally and stratigraphically controlled. This research uses Advanced Visible/Infrared Imaging Spectrometer (AVIRIS) data to quantitatively map the mineral-bound ammonium (buddingtonite) concentration in the altered volcanic rocks. Naturally occurring mineral-bound ammonium is fairly rare; however, it has been found to occur in gold-bearing hydrothermal deposits. Because of this association, it is thought that ammonium may be a useful too in exploration for gold and other metal deposits. Mineral-bound ammonium is produced when an ammonium ion (NH4+) replaces the alkali cation site (usually K+) in the crystal structure of silicate minerals such as feldspars, micas and clays. Buddingtonite is an ammonium feldspar. The ammonium originates in buried organic plant matter and is transported to the host rock by hydrothermal fluids. Ammonium alteration does not produce visible changes in the rock, and it is barely detectable with standard x-ray diffraction methods. It is clearly identified, however, by absorption features in short wave-infrared (SWIR) wavelengths (2.0 - 2.5 micrometers). The ammonium absorption features are believed to be caused by N-H vibrational modes and are analogous to hydroxyl (O-H) vibrational modes, only shifted slightly in wavelength. Buddingtonite absorption features in the near- and SWIR lie at 1.56, 2.02 and 2.12 micrometers. The feature at 2.12 micrometer is the strongest of the three and is the only one used in this study. The southern Cedar Mountains are sparsely vegetated and are an ideal site for a remote sensing study.

  13. Contributions of two cytosolic glutamine synthetase isozymes to ammonium assimilation in Arabidopsis roots. (United States)

    Konishi, Noriyuki; Ishiyama, Keiki; Beier, Marcel Pascal; Inoue, Eri; Kanno, Keiichi; Yamaya, Tomoyuki; Takahashi, Hideki; Kojima, Soichi


    Glutamine synthetase (GS) catalyzes a reaction that incorporates ammonium into glutamate and yields glutamine in the cytosol and chloroplasts. Although the enzymatic characteristics of the GS1 isozymes are well known, their physiological functions in ammonium assimilation and regulation in roots remain unclear. In this study we show evidence that two cytosolic GS1 isozymes (GLN1;2 and GLN1;3) contribute to ammonium assimilation in Arabidopsis roots. Arabidopsis T-DNA insertion lines for GLN1;2 and GLN1;3 (i.e. gln1;2 and gln1;3 single-mutants), the gln1;2:gln1;3 double-mutant, and the wild-type accession (Col-0) were grown in hydroponic culture with variable concentrations of ammonium to compare their growth, and their content of nitrogen, carbon, ammonium, and amino acids. GLN1;2 and GLN1;3 promoter-dependent green fluorescent protein was observed under conditions with or without ammonium supply. Loss of GLN1;2 caused significant suppression of plant growth and glutamine biosynthesis under ammonium-replete conditions. In contrast, loss of GLN1;3 caused slight defects in growth and Gln biosynthesis that were only visible based on a comparison of the gln1;2 single- and gln1;2:gln1;3 double-mutants. GLN1;2, being the most abundantly expressed GS1 isozyme, markedly increased following ammonium supply and its promoter activity was localized at the cortex and epidermis, while GLN1;3 showed only low expression at the pericycle, suggesting their different physiological contributions to ammonium assimilation in roots. The GLN1;2 promoter-deletion analysis identified regulatory sequences required for controlling ammonium-responsive gene expression of GLN1;2 in Arabidopsis roots. These results shed light on GLN1 isozyme-specific regulatory mechanisms in Arabidopsis that allow adaptation to an ammonium-replete environment.

  14. Assessment of the potential for ammonium nitrate formation and reaction in Tank 241-SY-101

    Energy Technology Data Exchange (ETDEWEB)

    Pederson, L.R.; Bryan, S.A.


    Two principal scenarios by which ammonium nitrate may be formed were considered: (a) precipitation of ammonium nitrate in the waste, and (b) ammonium nitrate formation via the gas phase reaction of ammonia and nitrogen dioxide. The first of these can be dismissed because ammonium ions, which are necessary for ammonium nitrate precipitation, can exist only in negligibly small concentrations in strongly alkaline solutions. Gas phase reactions between ammonia, nitrogen dioxide, and water vapor in the gas phase represent the most likely means by which ammonium nitrate aerosols could be formed in Tank 241-SY-101. Predicted ammonium nitrate formation rates are largely controlled by the concentration of nitrogen dioxide. This gas has not been detected among those gases vented from the wastes using Fourier Transform Infrared Spectrometry (FTIR) or mass spectrometry. While detection limits for nitrogen dioxide have not been established experimentally, the maximum concentration of nitrogen dioxide in the gas phase in Tank 241-SY-101 was estimated at 0.1 ppm based on calculations using the HITRAN data base and on FTIR spectra of gases vented from the wastes. At 50 C and with 100 ppm ammonia also present, less than one gram of ammonium nitrate per year is estimated to be formed in the tank. To date, ammonium nitrate has not been detected on HEPA filters in the ventilation system, so any quantity that has been formed in the tank must be quite small, in good agreement with rate calculations. The potential for runaway exothermic reactions involving ammonium nitrate in Tank 241-SY-101 is minimal. Dilution by non-reacting waste components, particularly water, would prevent hazardous exothermic reactions from occurring within the waste slurry, even if ammonium nitrate were present. 41 refs.

  15. Sulfation patterns determine cellular internalization of heparin-like polysaccharides


    Raman, Karthik; Mencio, Caitlin; Desai, Umesh R.; Kuberan, Balagurunathan


    Heparin is a highly sulfated polysaccharide which serves biologically relevant roles as an anticoagulant and anti-cancer agent. While it is well known that modification of heparin’s sulfation pattern can drastically influence its ability to bind growth factors and other extracellular molecules, very little is known about the cellular uptake of heparin and the role sulfation patterns serve in affecting its internalization. In this study, we chemically synthesized several fluorescently-labeled ...

  16. Glycosaminoglycan modifications in Duchenne muscular dystrophy: specific remodeling of chondroitin sulfate/dermatan sulfate. (United States)

    Negroni, Elisa; Henault, Emilie; Chevalier, Fabien; Gilbert-Sirieix, Marie; Van Kuppevelt, Toin H; Papy-Garcia, Dulce; Uzan, Georges; Albanese, Patricia


    Widespread skeletal muscle degeneration and impaired regeneration lead to progressive muscle weakness and premature death in patients with Duchenne muscular dystrophy (DMD). Dystrophic muscles are progressively replaced by nonfunctional tissue because of exhaustion of muscle precursor cells and excessive accumulation of extracellular matrix (ECM). Sulfated glycosaminoglycans (GAGs) are components of the ECM and are increasingly implicated in the regulation of biologic processes, but their possible role in the progression of DMD pathology is not understood. In the present study, we performed immunohistochemical and biochemical analyses of endogenous GAGs in skeletal muscle biopsies of 10 DMD patients and 11 healthy individuals (controls). Immunostaining targeted to specific GAG species showed greater deposition of chondroitin sulfate (CS)/dermatan (DS) sulfate in DMD patient biopsies versus control biopsies. The selective accumulation of CS/DS in DMD biopsies was confirmed by biochemical quantification assay. In addition, high-performance liquid chromatography analysis demonstrated a modification of the sulfation pattern of CS/DS disaccharide units in DMD muscles. In conclusion, our data open up a new path of investigation and suggest that GAGs could represent a new and original therapeutic target for improving the success of gene or cell therapy for the treatment of muscular dystrophies.

  17. Modeling of sulfation of potassium chloride by ferric sulfate addition during grate-firing of biomass

    DEFF Research Database (Denmark)

    Wu, Hao; Jespersen, Jacob Boll; Aho, Martti;


    Potassium chloride, KCl, formed from critical ash-forming elements released during combustion may lead to severe ash deposition and corrosion problems in biomass-fired boilers. Ferric sulfate, Fe2(SO4)3 is an effective additive, which produces sulfur oxides (SO2 and SO3) to convert KCl to the les...

  18. Inter vs. intraglycosidic acetal linkages control sulfation pattern in semi-synthetic chondroitin sulfate. (United States)

    Laezza, Antonio; De Castro, Cristina; Parrilli, Michelangelo; Bedini, Emiliano


    Microbial-sourced unsulfated chondroitin could be converted into chondroitin sulfate (CS) polysaccharide by a multi-step strategy relying upon benzylidenation and acetylation reactions as key-steps for its regioselective protection. By conducting the two reactions one- or two-pots, CSs with different sulfation patterns could be obtained at the end of the semi-synthesis. In particular, a CS polysaccharide possessing sulfate groups randomly distributed between positions 4 and 6 of N-acetyl-galactosamine (GalNAc) units could be obtained through the two-pots route, whereas the one-pot pathway allowed an additional sulfation at position 3 of some glucuronic acid (GlcA) units. This difference was ascribed to the stabilization of a labile interglycosidic benzylidene acetal involving positions O-3 and O-6 of some GlcA and GalNAc, respectively, when the benzylidene-acetylation reactions were conducted in a one-pot fashion. Isolation and characterization of a polysaccharide intermediate showing interglycosidic acetal moieties was accomplished.

  19. A facile synthesis of ω-aminoalkyl ammonium hydrogen phosphates

    Institute of Scientific and Technical Information of China (English)

    Wei Bo Kong; Xiao Yong Zhou; Yang Yang; Xing Yi Xie


    A series of ω-aminoalkyl ammonium hydrogen phosphates were synthesized through a simple and efficient three-step method.The starting materials,ω-aminoalkyl alcohols (AC-n,with carbon number n =3,4,5,6),were amino-protected with 9-fluorenylmethyl chloroformate (Fmoc-Cl),followed by phosphorylation with POCl3 and deprotection in piperidine/DMF The structures of each intermediate and final product were confirmed by 1H NMR,FTIR and mass spectrum.The yield of each step was about 77-92%,with a total yield higher than 56%.This new method was superior in low-cost raw materials,mild reaction temperatures (0-25 ℃) and easy purification methods.

  20. Rotavirus gastroenteritis-associated urinary ammonium acid urate crystals. (United States)

    Yokoyama, Tadafumi; Sugimoto, Naotoshi; Kato, Eiji; Ohta, Kazuhide; Ishikawa, Sayaka; Ueno, Kazuyuki; Shimizu, Masaki; Yachie, Akihiro


    Although ammonium acid urate (AAU) calculi are extremely rare renal stone components, it was recently found that many urinary tract calculi that cause post-renal renal failure in rotavirus (RV) gastroenteritis are AAU calculi. The mechanism of AAU calculi development in RV gastroenteritis has not been fully elucidated. We analyzed data from eight RV gastroenteritis patients who transiently had AAU crystals in their urinary sediment. In these patients, formation of AAU crystals occurred earlier than the formation of AAU calculi. No difference was observed in serum and urine uric acid levels between RV gastroenteritis patients with or without AAU crystals. Interestingly, fractional excretion of sodium was extremely low among patients with AAU crystals. These results suggest that the formation of AAU crystals might not be due to excretion of uric acid, but excretion of sodium.

  1. Review of Options for Ammonia/Ammonium Management

    Energy Technology Data Exchange (ETDEWEB)

    Nash, C. A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)


    This report is a review of literature supporting practical ammonia/ammonium destruction processes. Melter research supporting Hanford Low Activity Waste (LAW) glass production has shown that significant amounts of ammonia will be in the melter offgas condensate. Further work with secondary waste forms indicates the potential need to remove the ammonia, perhaps by an oxidative process. This review finds likely practical chemical methods to oxidize ammonia in aqueous solution at moderate temperatures and atmospheric pressure, using easily obtained reagents. Leading candidates include nitrite oxidation to produce nitrogen gas, various peroxide oxidative processes, and air stripping. This work reviews many other processes and provides reasoning to not consider those processes further for this application.

  2. Synthesis of tetramethyl ammonium hydroxide by cell diaphragm electrolytic method

    Institute of Scientific and Technical Information of China (English)


    Under the conditions of tetramethyl ammonia chloride (TMAC) used as starting material, Ti-based Dimensionally Stable Anode (DSA), stainless steel used as cathode and Nafion 900 cation membrane as cell diaphragm, this paper studies the synthesis of tetramethyl ammonium hydroxide (TMAH) by cell diaphragm electrolytic method, examining not only the effects of current density, concentration of starting material and cell temperature, on the product purity and current efficiency, but also the effects of electrolyte circulation rate on the service life of Ti-based DSA.The experiment puts forward an optimum processing condition, and experimental findings show that preparing TMAH by using this technique can obtain a current efficiency 74.7 % and get product with a purity greater than 99.9%.

  3. Computational Modeling of Degradation of Substituted Benzyltrimethyl Ammonium: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Long, H.; Pivovar, B. S.


    The degradation of cations on the alkaline exchange membranes is the major challenge for alkaline membrane fuel cells. In this paper, we investigated the degradation barriers by density functional theory for substituted benzyltrimethyl ammonium (BTMA+) cations, which is one of the most commonly used cations for alkaline exchange membranes. We found that substituted cations with electron-releasing substituent groups at meta-position of the benzyl ring could result in improved degradation barriers. However, after investigating more than thirty substituted BTMA+ cations with ten different substituent groups, the largest improvement of degradation barriers is only 1.6 kcal/mol. This implies that the lifetime of alkaline membrane fuel cells could increase from a few months to a few years by using substituted BTMA+ cations, an encouraging but still limited improvement for real-world applications.

  4. Integrated Data Collection Analysis (IDCA) Program — Ammonium Nitrate

    Energy Technology Data Exchange (ETDEWEB)

    Sandstrom, Mary M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Brown, Geoffrey W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Preston, Daniel N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pollard, Colin J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Warner, Kirstin F. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Sorensen, Daniel N. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Remmers, Daniel L. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Phillips, Jason J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Shelley, Timothy J. [Bureau of Alcohol, Tobacco and Firearms, Redstone Arsenal, AL (United States); Reyes, Jose A. [Applied Research Associates, Tyndall AFB, FL (United States); Hsu, Peter C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Reynolds, John G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)


    The Integrated Data Collection Analysis (IDCA) program is conducting a proficiency study for Small- Scale Safety and Thermal (SSST) testing of homemade explosives (HMEs). Described here are the results for impact, friction, electrostatic discharge, and differential scanning calorimetry analysis of ammonium nitrate (AN). AN was tested, in most cases, as both received from manufacturer and dried/sieved. The participants found the AN to be: 1) insensitive in Type 12A impact testing (although with a wide range of values), 2) completely insensitive in BAM friction testing, 3) less sensitive than the RDX standard in ABL friction testing, 4) less sensitive than RDX in ABL ESD testing, and 5) less sensitive than RDX and PETN in DSC thermal analyses.

  5. Studies on a Cationically Modified Quaternary Ammonium Salt of Lignin

    Institute of Scientific and Technical Information of China (English)

    YANG Ai-li; JIANG Wen-ju


    A new quaternary ammonium salt monomer was synthesized and a quaternary amination of lignin( noted as QL),with the monomer was carried out by grafting copolymerization. The products were characterized by Fourier Transform Infrared spectroscopy(FTIR). The experimental results indicate that the yield of the monomer was 99.06%, and the conversion of the monomer and the grafting yield of QL were 93.69% and 185.78%, respectively. The feasibility of QL as the fiocculant to be applied in color removal of five artificial dyes, eriochrome black T( dye A), gongo red( dye B), direct fast black G (dye C), cuprofix blue green B (dye D), and acid black ATT (dye E) was examined.Results show that QL exhibits the favorable flocculation performance and high stability.

  6. Antibacterial effect of composite resins containing quaternary ammonium polyethyleneimine nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Yudovin-Farber, Ira [Hebrew University of Jerusalem, Department of Medicinal Chemistry and Natural Products, School of Pharmacy, Faculty of Medicine (Israel); Beyth, Nurit; Weiss, Ervin I. [Hebrew University of Jerusalem, Department of Prosthodontics, Faculty of Dentistry (Israel); Domb, Abraham J., E-mail: [Hebrew University of Jerusalem, Department of Medicinal Chemistry and Natural Products, School of Pharmacy, Faculty of Medicine (Israel)


    Quaternary ammonium polyethyleneimine (QA-PEI)-based nanoparticles were synthesized by crosslinking with dibromopentane followed by N-alkylation with various alkyl halides and further N-methylation with methyl iodide. Insoluble pyridinium-type particles were prepared by suspension polymerization of 4-vinyl pyridine followed by N-alkylation with alkyl halides. Polyamine-based nanoparticles embedded in restorative composite resin at 1% w/w were tested for antibacterial activity against Streptococcus mutans using direct contact test. Activity analysis revealed that the alkyl chain length of the QA-PEI nanoparticles plays a significant role in antibacterial activity of the reagent. The most potent compound was octyl-alkylated QA-PEI embedded in restorative composite resin at 1% w/w that totally inhibited S. mutans growth in 3-month-aged samples. This data indicates that restorative composite resin with antibacterial properties can be produced by the incorporation of QA-PEI nanoparticles.

  7. Ammonium nitrate emulsion : physical properties and decomposition using thermal methods

    Energy Technology Data Exchange (ETDEWEB)

    Feng, H.; Goldthorp, S.; Singh, S.; Turcotte, R.


    This presentation discussed methods of determining the physical properties and decomposition rates of commercial water-based explosives. Ammonium nitrate emulsions can explode when heated to critical temperatures or when a localized thermal energy deposition occurs. An accelerating rate calorimeter (ARC) was used to investigate the emulsion under adiabatic conditions. Simultaneous mass spectroscopy (MS) Fourier Transform Infrared (FTIR) and differential scanning calorimetry (DSC) techniques were used to conduct an evolved gas analysis. Results of the analysis demonstrated that the AN emulsions have ARC onset temperatures of approximately 220 degrees C. The mass loss reaction occurred in 2 steps. The initial step was related to water evaporation and oil phase volatilization. The second step was related to AN decomposition in a closed system, and AN dissociation in an open system. tabs., figs.

  8. Lactulose production from cheese whey using recyclable catalyst ammonium carbonate. (United States)

    Seo, Yeong Hwan; Sung, Mina; Han, Jong-In


    Ammonium carbonate ((NH4)2CO3) was used as an alkaline catalyst of lactulose production from cheese whey. Maximum yield of 29.6% was obtained at reaction time of 28.44 min, (NH4)2CO3 of 0.76% at 97°C. During reaction, (NH4)2CO3 was fully decomposed to NH3 and CO2, and these gases were recovered. To boost up NH3 recovery, various methods such as heating, aeration, and pH adjustment were applied. The optimal condition for the purpose of NH3 retrieval was temperature of up to 60°C alongside aeration. Easy separation and recovery make (NH4)2CO3 a catalyst alternative to common alkaline chemicals especially for the weak alkaline reaction.

  9. Ammonium derivatives of chromenones and quinolinones as lead antimicrobial agents

    Indian Academy of Sciences (India)

    Shilpi Gupta; Seema Singh; Abha Kathuria; Manish Kumar; Sweta Sharma; Ram Kumar; Virinder S Parmar; Bharat Singh; Anjali Gupta; Erik Van Der Eycken; Gainda L Sharma; Sunil K Sharma


    A series of novel ammonium derivatives were synthesized and examined for their antimicrobial efficacy. Comparison of antimicrobial spectrum revealed that compounds 9, 11, 16 and 23 had strong potential against pathogens in vitro. Cytotoxicity results showed compound 9 to be least toxic, it is non-toxic to A549 and U87 cells in MTT assay and exhibits marginal toxicity (15-20%) to human erythrocytes at a concentration of 1000 g/ml as compared to 100% lysis of cells by 31.25 g/ml of the standard drug amphotericin B. This compound has MIC values in the range of 1.95-31.25 g/disc in DDA against different pathogens and may considered to be an important lead antimicrobial molecule for further exploration.

  10. Polishing of quartz by rapid etching in ammonium bifluoride. (United States)

    Vallin, Orjan; Danielsson, Rolf; Lindberg, Ulf; Thornell, Greger


    The etch rate and surface roughness of polished and lapped AT-cut quartz subjected to hot (90, 110, and 130 degrees C), concentrated (50, 65, 80 wt %) ammonium bi-fluoride have been investigated. Having used principal component analysis to verify experimental solidity and analyze data, we claim with confidence that this parameter space does not, as elsewhere stated, allow for a polishing effect or even a preserving setting. Etch rates were found to correlate well, and possibly logarithmically, with temperature except for the hottest etching applied to lapped material. Roughness as a function of temperature and concentration behaved well for the lapped material, but lacked systematic variation in the case of the polished material. At the lowest temperature, concentration had no effect on etch rate or roughness. Future efforts are targeted at temperatures and concentrations closer to the solubility limit.

  11. Polymerization and photochromism of ammonium molybdate in porous glass (United States)

    Pak, V. N.; Borisov, A. N.


    Modification of porous glass (PG) plates is carried out by impregnation with aqueous solutions of ammonium molybdate (NH4)2MoO4 with subsequent removal of water at 120°C. A long-wavelength shift of absorption spectra upon accumulation of the salt in PG indicates polymerization of MoO 4 2- anions at low concentrations of the encapsulated salt. Photochromism manifests itself as the anionic forms in PG become larger. UV irradiation of the modified plates causes enhancement of continuous absorption in the visible range. The proposed mechanism of photoreduction of the polianions in PG involves the removal of oxygen atoms from the bridging-Mo-O-Mo-bonds and stabilization of the colored forms by means of conjugation of the electrons released from the 4 d-levels of pentavalent molybdenum.

  12. Crystal structure of tris-(hydroxyl-ammonium) orthophosphate. (United States)

    Leinemann, Malte; Jess, Inke; Boeckmann, Jan; Näther, Christian


    The crystal structure of the title salt, ([H3NOH](+))3·[PO4](3-), consists of discrete hydroxyl-ammonium cations and ortho-phos-phate anions. The atoms of the cation occupy general positions, whereas the anion is located on a threefold rotation axis that runs through the phospho-rus atom and one of the phosphate O atoms. In the crystal structure, cations and anions are linked by inter-molecular O-H⋯O and N-H⋯O hydrogen bonds into a three-dimensional network. Altogether, one very strong O-H⋯O, two N-H⋯O hydrogen bonds of medium strength and two weaker bifurcated N-H⋯O inter-actions are observed.

  13. Antibacterial effect of composite resins containing quaternary ammonium polyethyleneimine nanoparticles (United States)

    Yudovin-Farber, Ira; Beyth, Nurit; Weiss, Ervin I.; Domb, Abraham J.


    Quaternary ammonium polyethyleneimine (QA-PEI)-based nanoparticles were synthesized by crosslinking with dibromopentane followed by N-alkylation with various alkyl halides and further N-methylation with methyl iodide. Insoluble pyridinium-type particles were prepared by suspension polymerization of 4-vinyl pyridine followed by N-alkylation with alkyl halides. Polyamine-based nanoparticles embedded in restorative composite resin at 1% w/w were tested for antibacterial activity against Streptococcus mutans using direct contact test. Activity analysis revealed that the alkyl chain length of the QA-PEI nanoparticles plays a significant role in antibacterial activity of the reagent. The most potent compound was octyl-alkylated QA-PEI embedded in restorative composite resin at 1% w/w that totally inhibited S. mutans growth in 3-month-aged samples. This data indicates that restorative composite resin with antibacterial properties can be produced by the incorporation of QA-PEI nanoparticles.

  14. Theoretical study on the reactivity of sulfate species with hydrocarbons (United States)

    Ma, Q.; Ellis, G.S.; Amrani, A.; Zhang, T.; Tang, Y.


    The abiotic, thermochemically controlled reduction of sulfate to hydrogen sulfide coupled with the oxidation of hydrocarbons, is termed thermochemical sulfate reduction (TSR), and is an important alteration process that affects petroleum accumulations in nature. Although TSR is commonly observed in high-temperature carbonate reservoirs, it has proven difficult to simulate in the laboratory under conditions resembling nature. The present study was designed to evaluate the relative reactivities of various sulfate species in order to provide greater insight into the mechanism of TSR and potentially to fill the gap between laboratory experimental data and geological observations. Accordingly, quantum mechanics density functional theory (DFT) was used to determine the activation energy required to reach a potential transition state for various aqueous systems involving simple hydrocarbons and different sulfate species. The entire reaction process that results in the reduction of sulfate to sulfide is far too complex to be modeled entirely; therefore, we examined what is believed to be the rate limiting step, namely, the reduction of sulfate S(VI) to sulfite S(IV). The results of the study show that water-solvated sulfate anions SO42 - are very stable due to their symmetrical molecular structure and spherical electronic distributions. Consequently, in the absence of catalysis, the reactivity of SO42 - is expected to be extremely low. However, both the protonation of sulfate to form bisulfate anions (HSO4-) and the formation of metal-sulfate contact ion-pairs could effectively destabilize the sulfate molecular structure, thereby making it more reactive. Previous reports of experimental simulations of TSR generally have involved the use of acidic solutions that contain elevated concentrations of HSO4- relative to SO42 -. However, in formation waters typically encountered in petroleum reservoirs, the concentration of HSO4- is likely to be significantly lower than the levels

  15. Cloud water chemistry and the production of sulfates in clouds (United States)

    Hegg, D. A.; Hobbs, P. V.


    Measurements are presented of the pH and ionic content of water collected in clouds over western Washington and the Los Angeles Basin. Evidence for sulfate production in some of the clouds is presented. Not all of the sulfur in the cloud water was in the form of sulfate. However, the measurements indicate that the production of sulfate in clouds is of considerable significance in the atmosphere. Comparison of field measurements with model results show reasonable agreement and suggest that the production of sulfate in cloud water is a consequence of more than one conversion mechanism.

  16. An Instrument to Measure Aircraft Sulfate Particle Emissions Project (United States)

    National Aeronautics and Space Administration — Aerodyne is developing a sulfate detection instrument, based on the Tunable Infrared Laser Differential Absorption Spectrophotometer (TILDAS) technology and...



  18. Basement membrane chondroitin sulfate proteoglycans: localization in adult rat tissues

    DEFF Research Database (Denmark)

    McCarthy, K J; Couchman, J R


    Heparan sulfate proteoglycans have been described as the major proteoglycan component of basement membranes. However, previous investigators have also provided evidence for the presence of chondroitin sulfate glycosaminoglycan in these structures. Recently we described the production...... and characterization of core protein-specific monoclonal antibodies (MAb) against a chondroitin sulfate proteoglycan (CSPG) present in Reichert's membrane, a transient extra-embryonic structure of rodents. This CSPG was also demonstrated to be present in adult rat kidney. We report here the tissue distribution...... sulfate proteoglycans previously described....

  19. Sulfate Reduction in Groundwater: Characterization and Applications for Remediation

    Energy Technology Data Exchange (ETDEWEB)

    Miao, Z.; Brusseau, M. L.; Carroll, Kenneth C.; Carreon-Diazconti, C.; Johnson, B.


    Sulfate is ubiquitous in groundwater, with both natural and anthropogenic sources. Sulfate reduction reactions play a significant role in mediating redox conditions and biogeochemical processes for subsurface systems. They also serve as the basis for innovative in-situ methods for groundwater remediation. An overview of sulfate reduction in subsurface environments is provided, with a specific focus on implications for groundwater remediation. A case study presenting the results of a pilot-scale ethanol injection test illustrates the advantages and difficulties associated with the use of electron-donor amendments for sulfate remediation.

  20. The "in and out" of glucosamine 6-O-sulfation: the 6th sense of heparan sulfate. (United States)

    El Masri, Rana; Seffouh, Amal; Lortat-Jacob, Hugues; Vivès, Romain R


    The biological properties of Heparan sulfate (HS) polysaccharides essentially rely on their ability to bind and modulate a multitude of protein ligands. These interactions involve internal oligosaccharide sequences defined by their sulfation patterns. Amongst these, the 6-O-sulfation of HS contributes significantly to the polysaccharide structural diversity and is critically involved in the binding of many proteins. HS 6-O-sulfation is catalyzed by 6-O-sulfotransferases (6OSTs) during biosynthesis, and it is further modified by the post-synthetic action of 6-O-endosulfatases (Sulfs), two enzyme families that remain poorly characterized. The aim of the present review is to summarize the contribution of 6-O-sulfates in HS structure/function relationships and to discuss the present knowledge on the complex mechanisms regulating HS 6-O-sulfation.

  1. Papillomavirus microbicidal activities of high-molecular-weight cellulose sulfate, dextran sulfate, and polystyrene sulfonate. (United States)

    Christensen, N D; Reed, C A; Culp, T D; Hermonat, P L; Howett, M K; Anderson, R A; Zaneveld, L J


    The high-molecular-weight sulfated or sulfonated polysaccharides or polymers cellulose sulfate, dextran sulfate, and polystyrene sulfonate were tested for microbicidal activity against bovine papillomavirus type 1 (BPV-1) and human papillomavirus type 11 (HPV-11) and type 40 (HPV-40). In vitro assays included the BPV-1-induced focus-forming assay and transient infection of human A431 cells with HPVs. The compounds were tested for microbicidal activity directly by preincubation with virus prior to addition to cell cultures and indirectly by addition of virus to compound-treated cells and to virus-coated cells to test inactivation of the virus after virus-cell binding. The data indicated that all three compounds showed direct microbicidal activity with 50% effective concentrations between 10 to 100 microg/ml. These concentrations were nontoxic to cell cultures for both assays. When a clone of C127 cells was tested for microbicidal activity, approximately 10-fold-less compound was required to achieve a 50% reduction in BPV-1-induced foci than for the uncloned parental C127 cells. Pretreatment of cells with compound prior to addition of virus also demonstrated strong microbicidal activity with dextran sulfate and polystyrene sulfonate, but cellulose sulfate required several orders of magnitude more compound for virus inactivation. Polystyrene sulfonate prevented subsequent infection of HPV-11 after virus-cell binding, and this inactivation was observed up to 4 h after addition of virus. These data indicate that the polysulfated and polysulfonated compounds may be useful nontoxic microbicidal compounds that are active against a variety of sexually transmitted disease agents including papillomaviruses.

  2. Controls of Soluble Al in Experimental Acid Sulfate Conditions and Acid Sulfate Soils

    Institute of Scientific and Technical Information of China (English)



    The controls of soluble Al concentration were examined in three situations of acid sulfate conditions:1) experimental acid sulfate conditions by addition of varying amounts of Al(OH)3(gibbsite) into a sequence of H2SO4 solutions;2)experimental acid sulfate conditions by addition of the same sequence of H2SO4 solutions into two non-cid sulfacte soil samples with known amounts of acid oxalate extractable Al; and 3) actual acid sulfate soil conditions.The experiment using gibbsite as an Al-bearing mineral showed that increase in the concentration of H2SO4 solution increased the soluble Al concentration,accompanied by a decrease i the solution pH, Increasing amount of gibbsite added to the H2SO4 solutions also increased soluble Al concentration,but resulted in an increase in solution pH.Within the H2SO4 concentration range of 0.0005-0.5mol L-1 and the Al(OH)3 range of 0.01-0.5g(in 25 mL of H2SO4 solutions),the input of H2SO4 had the major control on soluble Al Concentration and pH .The availability of Al(OH)3,however,was responsible for the spread fo the various sample points,with a tendency that the samples containing more gibbsite had a higher soluble Al concentration than those containing less gibbsite at equivalent pH levels.The experimental results from treatment of soil samples with H2SO4 solutions and the analytical results of acid sulfate soils also showed the similar trend.

  3. Synergistic Extraction of Gallium for Sulfate Solution

    Institute of Scientific and Technical Information of China (English)

    DENGTong; HUANGLijuan; 等


    A novel extractant mixture, di-2-ethylhexyl phosphate (DEHPA) plus HX, was propose and tested for recovering gallium from sulfate solution.It was found that the extraction capacity of DEPHA for gallium from sulfate solution could be enhanced significantly due to the synergistic effect of acidix extractant HX. Gallium extraction is negligible below pH 0 and highly sensitive to pH of aqueous phase in the range from 0 to 1, and satisfactory extraction can be gained at pH>1. More than 96% Ga extraction was obtained using 15% DEHPA plus 2% HX. Although Fe(Ⅲ) was found to be extracted preferentially to Ga (Ⅲ), effective extraction of Ga (Ⅲ) was possible by reducing ferric to the ferrous state prior to extraction. A loaded organic phase containing 0.48g·L-1 Ga could be produced from solution of 0.12g·L-1 Ga at A/O ratio of 4:1 via three mixer-settler operation stages. Gallium was stripped quantitatively from the loaded organic phase with 1.5mol·L-1 of sulfuric acid.

  4. Molecular Structure of Aminoguanidine Sulfate Monohydrate

    Institute of Scientific and Technical Information of China (English)

    CHEN Hong-yan; ZHANG Tong-lai; QIAO Xiao-jing; YANG Li; SHAO Feng-lei


    The single crystal of aminoguanidine sulfate monohydrate [(AG)2SO4·H2O] is obtained and its structure is determined by X-ray diffraction analysis. The compound crystallizes in orthorhombic system with space group Pnma and the empirical formula C2H16N8O5S. The unit cell parameters are as follows: a=0.6759(2)nm, b=1.4131(5)nm, c=1.1650(4)nm, V=1.1128(6)n m3, Z=4, Dc=1.578g/cm3, F(000)=560, s=1.069, μ(MoKα)=0.318mm-1. The final R and Wr are 0.0312 and 0.0833, respectively. The title compound is an ionic compound and its structure unit consists of two aminoguanidium cations, one sulfate anion and one crystal water molecule, which are interconnected by electrostatic forces and hydrogen bond s into net structure, making the title compound very stable. Under a linear heat ingrate, the thermal decomposition processes of (AG)2SO4·H2O have one en dothermal dehydration stage, one melting process and one exothermic decomposition stage at 50-400℃, and can evolve abundant gas products.

  5. Ammonium addition inhibits 13C-methane incorporation into methanotroph membrane lipids in a freshwater sediment

    NARCIS (Netherlands)

    Nold, s.c.; Boschker, H.T.S.; Pel, R.; Laanbroek, H.J.


    To investigate the effect of ammonium addition on the species composition and activity of freshwater methane oxidizing bacteria, intact sediment cores were labeled with (CH4)-C-13 and incubated under ambient and elevated ammonium concentrations. After 7 days, methanotroph activity was assessed by qu

  6. Clinoptilolite-based mixed matrix membranes for the selective recovery of potassium and ammonium

    NARCIS (Netherlands)

    Casadella, A.; Kuntke, P.; Schaetzle, O.; Loos, K.


    . A clinoptilolite-based mixed matrix membrane (MMM) was developed and studied for the selective recovery of ammonium and potassium. Adsorption of sodium (Na+), potassium (K+) and ammonium (NH4+) was investigated with single salt and equimolar salt solution under static and dynamic conditions. Furth

  7. Ammonium sorption from aqueous solutions by the natural zeolite Transcarpathian clinoptilolite studied under dynamic conditions. (United States)

    Sprynskyy, Myroslav; Lebedynets, Mariya; Terzyk, Artur P; Kowalczyk, Piotr; Namieśnik, Jacek; Buszewski, Bogusław


    The scope of this study is ammonium-ion uptake from synthetic aqueous solutions onto raw and pretreated forms of the natural zeolite Transcarpathian clinoptilolite under dynamic conditions. Hydrogen ions displaced exchangeable cations on the clinoptilolite in distilled water (sodium ions) and hydrochloric acid (sodium, potassium, and calcium ions) and destroyed the zeolite framework structure in the last case. Ammonium uptake onto the zeolite occurs by exchange with Na(+), Ca(2+), and K(+) ions. Although Na(+) ions were observed to be more easily exchanged for both hydrogen and ammonium ions, the role of Ca(2+) ions increased with zeolite saturation by NH(+)(4) ions. The maximum sorption capacity of the clinoptilolite toward NH(+)(4) ions, estimated under dynamic conditions, is significantly higher than that measured under static conditions; proximity of the values of a distribution coefficient and a retardation factor for different conditions (215-265 dm(3)/kg and 979-1107, respectively) allows us to use these parameters to model ammonium uptake onto the clinoptilolite. Slowing down or interruption in filtration resulted in the improvement of ammonium sorption properties of the zeolite. The ammonium removal improves with use of the finer fractions of the clinoptilolite up to 0.35 mm. A recycling study results confirmed the importance of external diffusion for ammonium sorption by the clinoptilolite. Preliminary treatment of the sorbent confirmed the predominant importance of the ion-exchange mechanism. The advantage of prior NaCl treatment of the clinoptilolite in improvement of ammonium removal over the other techniques was shown.

  8. Novel carbohydrate-based chiral ammonium ionic liquids derived from isomannide

    DEFF Research Database (Denmark)

    Kumar, Vineet; Pei, Cao; Olsen, Carl E.


    This report describes the synthesis and characterization of novel carbohydrate-based chiral ammonium ionic liquids using isomannide as a biorenewable substrate. The diastereomeric interactions of these chiral ammonium ionic liquids with racemic Mosher's acid salt have been studied using NMR, whic...

  9. Electroantennogram and behavioral responses of Anastrepha suspensa (Diptera: Tephritidae) to putrescine and ammonium bicarbonate lures. (United States)

    Kendra, Paul E; Montgomery, Wayne S; Epsky, Nancy D; Heath, Robert R


    At present, the most effective synthetic lures for pest Anastrepha fruit flies are multicomponent blends that include ammonia and the diamine synergist putrescine (1,4-diaminobutane). Both chemicals generally have been regarded as protein cues that result in female-biased attraction. Using electroantennography (EAG) and flight tunnel bioassays, this study evaluated response of the Caribbean fruit fly, Anastrepha suspensa (Loew) to vapors released from commercial lure formulations of ammonium bicarbonate and putrescine. Over a range of doses tested, EAG response to ammonium bicarbonate was equivalent for both sexes, but female response was significantly greater than male response to putrescine and to a 1:1 mixture of ammonium bicarbonate and putrescine. Amplitude of EAG response to the mixture was approximately equal to the summation of responses to the individual substrates. Using a fixed dose of substrate, EAG measurements from females 1-14 d old indicated that antennal sensitivity to both lures varied according to physiological state of the fly. Peak response to ammonium bicarbonate was recorded from immature females, peak response to putrescine from sexually mature females. In bioassays, more females were captured with ammonium bicarbonate plus putrescine than with ammonium bicarbonate alone. This difference was not observed in males, resulting in a higher female to male ratio in captures with ammonium bicarbonate plus putreseine (3:1) versus ammonium bicarbonate alone (1:1). Results suggest that separate olfactory receptors are involved in detection of the two semiochemicals, and that the putrescine component is primarily responsible for the female-biased attraction.

  10. 40 CFR 721.10154 - Quaternary ammonium compounds, dicoco alkyldimethyl, chlorides, reaction products with silica. (United States)


    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Quaternary ammonium compounds, dicoco alkyldimethyl, chlorides, reaction products with silica. 721.10154 Section 721.10154 Protection of Environment... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10154 Quaternary ammonium...

  11. Effect of quaternary ammonium salts on flotation behavior of aluminosilicate minerals

    Institute of Scientific and Technical Information of China (English)

    ZHAO Sheng-gui; ZHONG Hong; LIU Guang-yi


    The electrokinetic properties and flotation of diaspore, kaolinite, pyrophyllite and illite with quaternary ammonium salts collectors were studied. The results of flotation tests show that the collecting ability of quaternary ammonium salts for the four minerals is in the order(from strong to weak) of octadecyl dimethyl benzyl ammonium chloride(ODBA), cetyl trimethyl ammonium bromide(CTAB), dodecyl trimethyl ammonium chloride(DTAC). Under the condition of alkalescence, it is possible to separate the diaspore from the silicate minerals such as kaolinite, illite and pyrophyllite using quaternary ammonium salts as collector. Isoelectric points (IEP) of diaspore, kaolinite, pyrophyllite and illite are pH=6.0, 3.4, 2.3 and 3.2, respectively. Quaternary ammonium salts can change ζ-potential of the aluminosilicate minerals obviously. The flotation mechanisms were explained by ζ-potential and Fourier transform infrared spectrum (FT-IR) measurements. The results demonstrate that only electrostatic interaction takes place between aluminosilicate minerals (diaspore, kaolinite, pyrophyllite and illite) and quaternary ammonium salts.

  12. Ammonium-oxidizing bacteria facilitate aerobic degradation of sulfanilic acid in activated sludge. (United States)

    Chen, Gang; Ginige, Maneesha P; Kaksonen, Anna H; Cheng, Ka Yu


    Sulfanilic acid (SA) is a toxic sulfonated aromatic amine commonly found in anaerobically treated azo dye contaminated effluents. Aerobic acclimatization of SA-degrading mixed microbial culture could lead to co-enrichment of ammonium-oxidizing bacteria (AOB) because of the concomitant release of ammonium from SA oxidation. To what extent the co-enriched AOB would affect SA oxidation at various ammonium concentrations was unclear. Here, a series of batch kinetic experiments were conducted to evaluate the effect of AOB on aerobic SA degradation in an acclimatized activated sludge culture capable of oxidizing SA and ammonium simultaneously. To account for the effect of AOB on SA degradation, allylthiourea was used to inhibit AOB activity in the culture. The results indicated that specific SA degradation rate of the mixed culture was negatively correlated with the initial ammonium concentration (0-93 mM, R²= 0.99). The presence of AOB accelerated SA degradation by reducing the inhibitory effect of ammonium (≥ 10 mM). The Haldane substrate inhibition model was used to correlate substrate concentration (SA and ammonium) and oxygen uptake rate. This study revealed, for the first time, that AOB could facilitate SA degradation at high concentration of ammonium (≥ 10 mM) in an enriched activated sludge culture.

  13. On the influence of thiamine and ammonium ions on alcoholic fermentation

    NARCIS (Netherlands)

    Maesen, Th.J.M.


    1. 1. In a glucose-sodium acetate medium of pH 5.6 the fermentation rate of bakers' yeast remains constant at a low level during several hours, while in the presence of ammonium sulphate it gradually increases. The rise is steeper in the presence of thiamine. 2. 2. After the ammonium ions have been

  14. The effect of the ammonium ion on activated-sludge settling properties

    DEFF Research Database (Denmark)

    Novak, John Thomas


    by addition of sodium or ammonium, the interfacial settling velocity decreased, although the greatest drop was in the reactor containing ammonium. When addition of the nitrification inhibitor was stopped, rapid recovery of nitrification occurred but the settling properties improved more slowly. It seemed...

  15. Nitrogen phosphoric fertilizer production technology on the base of Central Kyzylkum phosphorites and ammonium nitrate melt

    Directory of Open Access Journals (Sweden)

    Shavkat Namazov


    Full Text Available The process of obtaining nitrogen phosphoric fertilizer by introduction Central Kyzylkum phosphates and ammonium nitrate melt is studied. On the base of these results production technology diagram for nitrogen phosphoric fertilizer is offered. The given technology was approved and developed at the functioning devices of OJSC “NAVOIAZOT” ammonium nitrate shop.

  16. Ammonium assimilation: An important accessory during aerobic denitrification of Pseudomonas stutzeri T13. (United States)

    Sun, Yilu; Feng, Liang; Li, Ang; Zhang, Xuening; Yang, Jixian; Ma, Fang


    The present study investigated effect of ammonium utilization on aerobic denitrification by Pseudomonas stutzeri T13. Per nitrogen balance calculation, all consumed ammonium was utilized as nitrogen source for cell propagation by assimilation rather than heterotrophic nitrification. Total organic carbon (TOC) and ammonium were necessary substrates to sustain heterotrophic propagation of P. stutzeri T13 at optimum proportion equal to seven. Under aerobic condition, nitrate was utilized as substitute nitrogen source when ammonium was completely exhausted. Biomass production effectively increased with increasing initial ammonium from 0mg/L to 100mg/L. Owing to enlarged biomass, average nitrate reduction rate increased from 7.36mgL(-1)h(-1) to 11.95mgL(-1)h(-1). Such process also successfully reduced nitrite accumulation from 121.8mg/L to 66.16mg/L during aerobic denitrification. As important accessory during aerobic denitrification, ammonium assimilation efficiently doubled total nitrogen (TN) removal from 54.97mg/L (no ammonium provided) to 113.1mg/L (100mg/L ammonium involved).

  17. 75 FR 56489 - Separation Distances of Ammonium Nitrate and Blasting Agents From Explosives or Blasting Agents... (United States)


    ... Ammonium Nitrate and Blasting Agents From Explosives or Blasting Agents (2002R-226P) AGENCY: Bureau of... CFR 555.220 set forth a table of separation distances of ammonium nitrate and blasting agents from explosives or blasting agents followed by six explanatory notes. Note three (3) states that the...

  18. 75 FR 41725 - Food Additives Permitted in Feed and Drinking Water of Animals; Ammonium Formate (United States)


    ... Additives Permitted in Feed and Drinking Water of Animals; Ammonium Formate AGENCY: Food and Drug... regulations for food additives permitted in feed and drinking water of animals to provide for the safe use of ammonium formate as an acidifying agent in swine feed. This action is in response to a food...

  19. Alkali metal and ammonium chlorides in water and heavy water (binary systems)

    CERN Document Server

    Cohen-Adad, R


    This volume surveys the data available in the literature for solid-fluid solubility equilibria plus selected solid-liquid-vapour equilibria, for binary systems containing alkali and ammonium chlorides in water or heavy water. Solubilities covered are lithium chloride, sodium chloride, potassium chloride, rubidium chloride, caesium chloride and ammonium chloride in water and heavy water.

  20. Suppression of interference in the AAS determination of chromium by use of ammonium bifluoride. (United States)

    Purushottam, A; Naidu, P P; Lal, S S


    Addition of 1% of ammonium bifluoride successfully suppresses interference by diverse ions in the atomic-absorption determination of chromium(VI). If the sample solutions also contain chromium(III) addition of 1% of ammonium bifluoride and 0.2% of sodium sulphate is recommended for the suppression.

  1. Irritant contact dermatitis due to ammonium bifluoride in two infant twins. (United States)

    Toledo, Fernando; Silvestre, Juan Francisco; Cuesta, Laura; Bañuls, José


    Ammonium bifluoride is one of the most corrosive acids that may produce severe chemical burns when in contact with skin. This hazardous chemical is widely used in household products. We report two pediatric cases of irritant contact dermatitis after exposure to a rust remover, which contained ammonium bifluoride.

  2. Nitrogen removal by autotrophic ammonium oxidizing bacteria enrichment under anaerobic conditions

    Directory of Open Access Journals (Sweden)

    Pongsak (Lek Noophan


    Full Text Available Sludge from an anoxic tank at the centralized wastewater treatment plant, Nong Khaem, Bangkok, Thailand, was inoculatedin an anaerobic sequencing batch reactor (ASBR. The optimal compositions and operating conditions of the stock of autotrophic ammonium oxidizing bacteria medium were determined. The process of oxidizing ammonium with bacteria under anaerobic conditions is often referred to as the Anammox process (NO2- to N2 gas, using NH4+ as the electron donor and NO2- as the electron acceptor. The startup period for the anammox culture took more than three months. With ammoniumand nitrite concentration ratios of 1:1.38 and 1:1.6, the nitrogen conversion rate zero order. Fluorescent in situ hybridization(FISH was used to identify specific autotrophic ammonium oxidizing bacteria (Nitrosomonas spp., Candidatus Brocadia anammoxidans, and Candidatus Kuenenia stuttgartiensis. Results from this work demonstrated a shift in the species of ammonium oxidizing bacteria from Nitrosomonas spp. to Candidati Brocadia anammoxidans and Kuenenia stuttgartiensis, with increased ammonium concentrations from 3 mM to 15 mM. Under NH4+:NO2- ratios of 1:1.38 and 1:1.6 the ammoniumoxidizing bacteria were able to remove both ammonium and nitrite simultaneously. The specific nitrogen removal rate of theanammox bacteria (Candidati Brocadia anammoxidans and Kuenenia stuttgartiensis was significantly higher than that of anaerobic ammonium oxidizing bacteria (Nitrosomonas spp.. Anaerobic ammonium oxidizing bacteria (Candidati Brocadia anammoxidans and Kuenenia stuttgartiensis are strict anaerobes.

  3. Ammonium across a Selective Polymer Inclusion Membrane : Characterization, Transport, and Selectivity

    NARCIS (Netherlands)

    Casadella, Anna; Schaetzle, Olivier; Loos, Katja


    The recovery of ammonium from urine requires distinguishing and excluding sodium and potassium. A polymer inclusion membrane selective for ammonium is developed using an ionophore based on pyrazole substituted benzene. The interactions of the components are studied, as well as their effect on transp

  4. Uptake and diffusion of short chain alcohols into sulfuric acid and ammonium bisulfate solutions: considering the role of water in secondary organic aerosol formation. (United States)

    van Loon, L. L.; Minor, R. N.; Allen, H. C.


    Secondary organic aerosol formation is of great interest since it may constitute an important fraction of tropospheric aerosols. These aerosols often contain a significant amount of sulfuric acid (40-80 wt%), which can be partially neutralized by ammonia, the most abundant basic species in the atmosphere. We have investigated the uptake of short-chain alcohols (n=1, 4, 6) by sulfuric acid and ammonium bisulfate solutions. First, methanol-sulfuric acid solutions were investigated using Raman spectroscopy. In 70+ wt% solutions of sulfuric acid, the formation of methyl sulfate was observed. In solutions of 70 wt% sulfuric acid or less no reaction was observed. While sulfuric acid is partially neutralized by ammonia, ammonium bisulfate is still quite acidic (pH 2). Studies have shown enhanced oxidation of gas-phase species in the presence of acidic particles such as NH4HSO4,1 suggesting a reaction between the particles and organic species. Solutions of ammonium bisulfate and methanol were investigated, but no methyl sulfate was detected. The surface enhancement of alcohols on sulfuric acid solutions was also investigated using sum frequency generation spectroscopy. From all these experiments we conclude that the formation of organosulfates, and therefore possible aerosol growth, is controlled by the amount of water present in the system. Second, Raman spectroscopy was used to determine the diffusion coefficients of methanol in sulfuric acid solutions. This method allows the diffusion of gas-phase methanol into aqueous solutions to be monitored simply using a Raman probe over the course of several hours. From the time data we are able to extract the diffusion coefficients. We have determined DAB = (1.7 ± 0.2) x 10^{-5} cm2/s for methanol into water and DAB = (2.5 ± 0.5) x 10^{-5} cm2/s for methanol into 96.6 wt% sulfuric acid at 293 K. 1. M. Jang, N. M. Czoschke, A. L. Northcross, Environ. Sci. Technol., 39, 164 (2005).

  5. Models of oxic respiration, denitrification and sulfate reduction in zones of coastal upwelling (United States)

    Canfield, D. E.


    Coastal upwelling zones support some of the highest rates of primary production in the oceans. The settling and subsequent decomposition of this organic matter promotes oxygen depletion. In the Eastern tropical North and South Pacific and the Arabian Sea, large tracts of anoxic water develop, where intensive N 2 production through denitrification and anammox accounts for about 1/3 of the total loss of fixed nitrogen in the marine realm. It is curious that despite extensive denitrification in these waters, complete nitrate removal and the onset of sulfate reduction is extremely rare. A simple box model is constructed here to reproduce the dynamics of carbon, oxygen and nutrient cycling in coastal upwelling zones. The model is constructed with five boxes, where water is exchanged between the boxes by vertical and horizontal mixing and advection. These primary physical drivers control the dynamics of the system. The model demonstrates that in the absence of nitrogen fixation, the anoxic waters in a coastal upwelling system will not become nitrate free. This is because nitrate is the limiting nutrient controlling primary production, and if nitrate concentration becomes too low, primary production rate drops and this reduces rates of nitrate removal through N 2 production. With nitrogen fixation, however, complete nitrate depletion can occur and sulfate reduction will ensue. This situation is extremely rare in coastal upwelling zones, probably because nitrogen-fixing bacteria do not prosper in the high nutrient, turbid waters as typically in these areas. Finally, it is predicted here that the chemistry of the upwelling system will develop in a similar matter regardless whether N 2 production is dominated by anaerobic ammonium oxidation (anammox) or canonical heterotrophic denitrification.

  6. Chondroitin sulfate N-acetylgalactosaminyltransferase-1 (CSGalNAcT-1) involved in chondroitin sulfate initiation: Impact of sulfation on activity and specificity. (United States)

    Gulberti, Sandrine; Jacquinet, Jean-Claude; Chabel, Matthieu; Ramalanjaona, Nick; Magdalou, Jacques; Netter, Patrick; Coughtrie, Michael W H; Ouzzine, Mohamed; Fournel-Gigleux, Sylvie


    Glycosaminoglycan (GAG) assembly initiates through the formation of a linkage tetrasaccharide region serving as a primer for both chondroitin sulfate (CS) and heparan sulfate (HS) chain polymerization. A possible role for sulfation of the linkage structure and of the constitutive disaccharide unit of CS chains in the regulation of CS-GAG chain synthesis has been suggested. To investigate this, we determined whether sulfate substitution of galactose (Gal) residues of the linkage region or of N-acetylgalactosamine (GalNAc) of the disaccharide unit influences activity and specificity of chondroitin sulfate N-acetylgalactosaminyltransferase-1 (CSGalNAcT-1), a key glycosyltransferase of CS biosynthesis. We synthesized a series of sulfated and unsulfated analogs of the linkage oligosaccharide and of the constitutive unit of CS and tested these molecules as potential acceptor substrates for the recombinant human CSGalNAcT-1. We show here that sulfation at C4 or C6 of the Gal residues markedly influences CSGalNAcT-1 initiation activity and catalytic efficiency. Kinetic analysis indicates that CSGalNAcT-1 exhibited 3.6-, 1.6-, and 2.2-fold higher enzymatic efficiency due to lower K(m) values toward monosulfated trisaccharides substituted at C4 or C6 position of Gal1, and at C6 of Gal2, respectively, compared with the unsulfated oligosaccharide. This highlights the critical influence of Gal substitution on both CSGalNAcT-1 activity and specifity. No GalNAcT activity was detected toward sulfated and unsulfated analogs of the CS constitutive disaccharide (GlcA-β1,3-GalNAc), indicating that CSGalNAcT-1 was involved in initiation but not in elongation of CS chains. Our results strongly suggest that sulfation of the linkage region acts as a regulatory signal in CS chain initiation.

  7. Interactions between nitrate and ammonium in their uptake, allocation, assimilation, and signaling in plants. (United States)

    Hachiya, Takushi; Sakakibara, Hitoshi


    Nitrogen (N) availability is a major factor determining plant growth and productivity. Plants acquire inorganic N from the soil, mainly in the form of nitrate and ammonium. To date, researchers have focused on these N sources, and demonstrated that plants exhibit elaborate responses at both physiological and morphological levels. Mixtures of nitrate and ammonium are beneficial in terms of plant growth, as compared to nitrate or ammonium alone, and therefore synergistic responses to both N sources are predicted at different steps ranging from acquisition to assimilation. In this review, we summarize interactions between nitrate and ammonium with respect to uptake, allocation, assimilation, and signaling. Given that cultivated land often contains both nitrate and ammonium, a better understanding of the synergism between these N sources should help to identify targets with the potential to improve crop productivity.

  8. Extraction of IgG from serum of rabbit infected with Schistosoma japonicum by saturated ammonium sulphate%硫酸铵法提取血吸虫感染兔血清IgG初探

    Institute of Scientific and Technical Information of China (English)

    兰炜明; 姜唯声; 谢曙英; 徐银; 戴坤教; 高晓晖; 曾小军


    Objective To explore the feasibility of preparing the schistosomiasis positive reference product by the method of ammonium sulfate precipitation to extract the IgG from the infected rabbits ’ serum of Schistosoma japonicum. Methods We used the saturated ammonium sulfate solution to precipitate and separate the IgG from the infected rabbits ’ serum. Compared the titer of infected rabbits’ serum with the separated IgG,and compared unfreeze-drying titer of IgG with the freeze-drying by IHA,also studied the stability of freeze-drying IgG after we dissolve with water. Results The titer of the infected rabbits’ serum was 1:320 used to extract IgG by the method of ammonium sulfate precipitation,we dialysised,concentrated the liquid of the extracted IgG to the original volume,the extracted IgG titer was 1:320. the negative rabbits’ serum and sucrose as the protein protective agent added to the extracted IgG to freeze-drying,the extracted IgG titer of the unfreeze-drying and the freeze-drying were 1:160. The titer of the freeze-drying IgG dissolved in water changed with the time,the 0th,3rd,6th and 8th titer is 1:160,1:80,1:40 and 1:40 respectively. Conclusion All of the process of the ammonium sulfate precipitation method to extract the IgG and the freeze-dry-ing can not chang the titer of the antibody,but the process adding the protein protective agent to the extracted IgG reduced the titer,the titer of freeze-drying IgG dissolve with water falled after the 3rd. The ammonium sulfate precipitation method is suitable for extracting the IgG from the infected rabbit serum.%目的:探索硫酸铵法提取血吸虫感染兔血清IgG用于制备阳性参考品的可行性。方法采用饱和硫酸铵溶液对感染兔血清中IgG进行沉淀分离,IHA试剂测定分离前后、冻干前后的抗体滴度以及冻干IgG复溶后的稳定性。结果滴度为1:320的血吸虫感染兔血清经硫酸铵沉淀法提取IgG,经透析、浓缩至

  9. Use of ammonium formate in QuEChERS for high-throughput analysis of pesticides in food by fast, low-pressure gas chromatography and liquid chromatography tandem mass spectrometry. (United States)

    González-Curbelo, Miguel Ángel; Lehotay, Steven J; Hernández-Borges, Javier; Rodríguez-Delgado, Miguel Ángel


    The "quick, easy, cheap, effective, rugged, and safe" (QuEChERS) approach to sample preparation is widely applied in pesticide residue analysis, but the use of magnesium sulfate and other nonvolatile compounds for salting out in the method is not ideal for mass spectrometry. In this study, we developed and evaluated three new different versions of the QuEChERS method using more volatile salts (ammonium chloride and ammonium formate and acetate buffers) to induce phase separation and extraction of 43 representative pesticide analytes of different classes. Fast low-pressure gas chromatography tandem mass spectrometry (LPGC-MS/MS) and liquid chromatography (LC)-MS/MS were used for analysis. The QuEChERS AOAC Official Method 2007.01 was also tested for comparison purposes. Of the studied methods, formate buffering using 7.5g of ammonium formate and 15mL of 5% (v/v) formic acid in acetonitrile for the extraction of 15g of sample (5g for wheat grain) provided the best performance and practical considerations. Method validation was carried out with and without the use of dispersive solid-phase extraction for cleanup, and no significant differences were observed for the majority of pesticides. The method was demonstrated in quantitative analysis for GC- and LC-amenable pesticides in 4 representative food matrices (apple, lemon, lettuce, and wheat grain). With the typical exceptions of certain pH-dependent and labile pesticides, 90-110% recoveries and food applications.

  10. Anaerobic ammonium oxidation in traditional municipal wastewater treatment plants with low-strength ammonium loading: Widespread but overlooked. (United States)

    Wang, Shanyun; Peng, Yongzhen; Ma, Bin; Wang, Shuying; Zhu, Guibing


    Occurrence of anaerobic ammonium oxidation (anammox) in marine and freshwater systems has greatly changed our understanding of global nitrogen (N) cycle and promoted the investigation of the role and ecological features of anammox in anthropogenic ecosystems. This study focused on the spatio-temporal abundance, activity, and biodiversity of anammox bacteria in full-scale municipal wastewater treatment plants (WWTPs) via traditional nitrification/denitrification route with low-strength ammonium loading. The anammox bacteria were detected in all the treatment units at the five WWTPs tested, even in aerobic zones (dissolved oxygen >2 mg L(-1)) with abundance of 10(5)-10(7) hydrazine synthase (hzs) gene copies g(-1). The (15)N-isotope tracing technology revealed that the anammox rates in WWTPs ranged from 0.08 to 0.36 μmol N g(-1) h(-1) in winter and 0.12-1.20 μmol N g(-1) h(-1) in summer with contributions of 2.05-6.86% and 1.71-7.26% to N2 production, respectively. The diversity of anammox bacteria in WWTPs was distributed over only two genera, Brocadia and Kuenenia. Additionally, the exploration of potential interspecies relationships indicated that ammonia oxidation bacteria (AOB) was the major nitrite-substrate producer for anammox during nitrification, while Nitrospira, a nitrite oxidation bacteria (NOB), was the potential major competitor for nitrite. These results suggested the contribution of N-removal by the widespread of anammox has been overlooked in traditional municipal WWTPs, and the ecological habitats of anammox bacteria in anthropogenic ecosystems are much more abundant than previously assumed.

  11. Fabrication of ammonium perchlorate/copper-chromium oxides core-shell nanocomposites for catalytic thermal decomposition of ammonium perchlorate

    Energy Technology Data Exchange (ETDEWEB)

    Eslami, Abbas, E-mail: [Department of Inorganic Chemistry, Faculty of Chemistry, University of Mazandaran, P.O.Box 47416-95447, Babolsar (Iran, Islamic Republic of); Juibari, Nafise Modanlou [Department of Inorganic Chemistry, Faculty of Chemistry, University of Mazandaran, P.O.Box 47416-95447, Babolsar (Iran, Islamic Republic of); Hosseini, Seyed Ghorban [Department of Chemistry, Malek Ashtar University of Technology, P.O. Box 16765-3454, Tehran (Iran, Islamic Republic of)


    The ammonium perchlorate/Cu(II)-Cr(III)-oxides(AP/Cu-Cr-O) core-shell nanocomposites were in-situ prepared by deposition of copper and chromium oxides on suspended ammonium perchlorate particles in ethyl acetate as solvent. The results of differential scanning calorimetery (DSC) and thermal gravimetric analysis (TGA) experiments showed that the nanocomposites have excellent catalytic effect on the thermal decomposition of AP, so that the released heat increases up to about 3-fold over initial values, changing from 450 J/g for pure AP to 1510 J/g for most appropriate mixture. For better comparison, single metal oxide/AP core-shell nanocomposite have also been prepared and the results showed that they have less catalytic effect respect to mixed metal oxides system. Scanning electron microscopy (SEM) results revealed homogenous deposition of nanoparticles on the surface of AP and fabrication of core-shell structures. The kinetic parameters of thermal decomposition of both pure AP and AP/Cu-Cr-O samples have been calculated by Kissinger method and the results showed that the values of pre-exponential factor and activation energy are higher for AP/Cu-Cr-O nanocomposite. The better catalytic effect of Cu-Cr-O nanocomposites is probably attributed to the synergistic effect between Cu{sup 2+} and Cr{sup 3+} in the nanocomposites, smaller particle size and more crystal defect. - Highlights: • The Cu-Cr-O nanoparticles were synthesized by chemical liquid deposition method. • Then, the AP/Cu-Cr-O core-shell nanocomposites were prepared. • The core-shell samples showed high catalytic activity for AP decomposition. • Thermal decomposition of samples occurs at lower temperature range.

  12. A radioimmunoassay for measurement of thyroxine sulfate

    Energy Technology Data Exchange (ETDEWEB)

    Chopra, I.J.; Santini, F.; Hurd, R.E.; Chua Teco, G.N. (Univ. of California Center for the Health Sciences, Los Angeles (United States))


    A highly sensitive, specific, and reproducible RIA has been developed to measure T[sub 4] sulfate (T[sub 4]S) in ethanol extracts of serum. rT[sub 3] sulfate (rT[sub 3]S) cross-reacted 7.1%, and T[sub 3]S cross-reacted 0.59% in the RIA; T[sub 4], T[sub 3], rT[sub 3] and 3,3[prime]-diiodothyronine cross-reacted 0.004% or less. The recovery of nonradioactive T[sub 4]S added to serum averaged 95%. The detection threshold of the RIA was 18 pmol/L. The coefficient of variation averaged 6.9% within an assay and 12% between assays. T[sub 4]S was bound by T[sub 4]-binding globulin and albumin in serum. The free fraction of T[sub 4]S in four normal sera averaged 0.06% compared to a value of 0.03% for T[sub 4] (P < 0.001). The serum concentration of T[sub 4]S was (mean [+-] SE) 19 [+-] 1.2 pmol/L in normal subjects, 33 [+-] 10 in hyperthyroid patients with Graves disease, 42 [+-] 15 in hypothyroid patients, 34 [+-] 6.9 in patients with systematic nonthyroidal illnesses, 21 [+-] 4.3 in pregnant women at 15-40 weeks gestation, and 245 [+-] 26 in cord blood sera of newborns; the value in the newborn was significantly different from normal (P < 0.001). Administration of sodium ipodate (Oragrafin; 3 g, orally) to hyperthyroid patients was associated with a transient increase in serum T[sub 4]S. The T[sub 4]S content of the thyroid gland was less than 1/4000th that of T[sub 4]. We conclude that (1) T[sub 4]S is a normal component of human serum, and its levels are markedly increased in newborn serum and amniotic fluid; and (2) the sulfation pathway plays an important role in the metabolism of T[sub 4] in man. 28 refs., 4 figs., 2 tabs.

  13. The platelet glycoprotein thrombospondin binds specifically to sulfated glycolipids. (United States)

    Roberts, D D; Haverstick, D M; Dixit, V M; Frazier, W A; Santoro, S A; Ginsburg, V


    The human platelet glycoprotein thrombospondin (TSP) binds specifically and with high affinity to sulfatides (galactosylceramide-I3-sulfate). Binding of 125I-TSP to lipids from sheep and human erythrocytes and human platelets resolved on thin layer chromatograms indicates that sulfatides are the only lipids in the membrane which bind TSP. Binding to less than 2 ng of sulfatide could be detected. TSP failed to bind to other purified lipids including cholesterol 3-sulfate, phospholipids, neutral glycolipids, and gangliosides. Binding of 125I-TSP was inhibited by unlabeled TSP, by low pH, and by reduction of intersubunit disulfide bonds with dithiothreitol. A monoclonal antibody against TSP (A2.5), which inhibits hemagglutination and agglutination of fixed activated platelets by TSP, strongly inhibited TSP binding to sulfatides. A second monoclonal antibody (C6.7), which inhibits hemagglutination and aggregation of thrombin-activated live platelets, weakly inhibited sulfatide binding. Binding was inhibited by high ionic strength and by some monosaccharide sulfates including methyl-alpha-D-GlcNAc-3-sulfate. Neutral sugars did not inhibit. Fucoidan, a sulfated fucan, strongly inhibited binding with 50% inhibition at 0.3 micrograms/ml fucoidan. Other sulfated polysaccharides including heparin and dextran sulfates were good inhibitors, whereas hyaluronic acid and keratan sulfate were very weak.

  14. Transmission spectra study of sulfate substituted potassium dihydrogen phosphate

    KAUST Repository



    Potassium dihydrogen phosphate (KDP) crystals with different amounts of sulfate concentration were grown and the transmittance spectrum was studied. A crystal with high sulfate replacement density exhibits heavy absorption property in the ultraviolet region which confirms and agrees well with former results. © 2013 Astro Ltd.

  15. Biological processes for the production of aryl sulfates

    DEFF Research Database (Denmark)


    The present invention generally relates to the field of biotechnology as it applies to the production of aryl sulfates using polypeptides or recombinant cells comprising said polypeptides. More particularly, the present invention pertains to polypeptides having aryl sulfotransferase activity......, recombinant host cells expressing same and processes for the production of aryl sulfates employing these polypeptides or recombinant host cells....

  16. Serum Indoxyl Sulfate Associates with Postangioplasty Thrombosis of Dialysis Grafts. (United States)

    Wu, Chih-Cheng; Hsieh, Mu-Yang; Hung, Szu-Chun; Kuo, Ko-Lin; Tsai, Tung-Hu; Lai, Chao-Lun; Chen, Jaw-Wen; Lin, Shing-Jong; Huang, Po-Hsun; Tarng, Der-Cherng


    Hemodialysis vascular accesses are prone to recurrent stenosis and thrombosis after endovascular interventions.In vitro data suggest that indoxyl sulfate, a protein-bound uremic toxin, may induce vascular dysfunction and thrombosis. However, there is no clinical evidence regarding the role of indoxyl sulfate in hemodialysis vascular access. From January 2010 to June 2013, we prospectively enrolled patients undergoing angioplasty for dialysis access dysfunction. Patients were stratified into tertiles by baseline serum indoxyl sulfate levels. Study participants received clinical follow-up at 6-month intervals until June 2014. Primary end points were restenosis, thrombosis, and failure of vascular access. Median follow-up duration was 32 months. Of the 306 patients enrolled, 262 (86%) had symptomatic restenosis, 153 (50%) had access thrombosis, and 25 (8%) had access failure. In patients with graft access, free indoxyl sulfate tertiles showed a negative association with thrombosis-free patency (thrombosis-free patency rates of 54%, 38%, and 26% for low, middle, and high tertiles, respectively;P=0.001). Patients with graft thrombosis had higher free and total indoxyl sulfate levels. Using multivariate Cox regression analysis, graft thrombosis was independently predicted by absolute levels of free indoxyl sulfate (hazard ratio=1.14;P=0.01) and free indoxyl sulfate tertiles (high versus low, hazard ratio=2.41;P=0.001). Results of this study provide translational evidence that serum indoxyl sulfate is a novel risk factor for dialysis graft thrombosis after endovascular interventions.

  17. Sulfate reduction at low pH in organic wastewaters

    NARCIS (Netherlands)

    Lopes, S.I.C.


    The objective of the research described in this thesis was to investigate the operational window of dissimilatory sulfate reduction at low pH (6, 5 and 4) during the acidification of organic wastewaters. High sulfate reduction efficiencies at low pH are desirable for a more sustainable operation of

  18. Sulfation of ractopamine and salbutamol by the human cytosolic sulfotransferases. (United States)

    Ko, Kyounga; Kurogi, Katsuhisa; Davidson, Garrett; Liu, Ming-Yih; Sakakibara, Yoichi; Suiko, Masahito; Liu, Ming-Cheh


    Feed additives such as ractopamine and salbutamol are pharmacologically active compounds, acting primarily as β-adrenergic agonists. This study was designed to investigate whether the sulfation of ractopamine and salbutamol may occur under the metabolic conditions and to identify the human cytosolic sulfotransferases (SULTs) that are capable of sulfating two major feed additive compounds, ractopamine and salbutamol. A metabolic labelling study showed the generation and release of [(35)S]sulfated ractopamine and salbutamol by HepG2 human hepatoma cells labelled with [(35)S]sulfate in the presence of these two compounds. A systematic analysis using 11 purified human SULTs revealed SULT1A3 as the major SULT responsible for the sulfation of ractopamine and salbutamol. The pH dependence and kinetic parameters were analyzed. Moreover, the inhibitory effects of ractopamine and salbutamol on SULT1A3-mediated dopamine sulfation were investigated. Cytosol or S9 fractions of human lung, liver, kidney and small intestine were examined to verify the presence of ractopamine-/salbutamol-sulfating activity in vivo. Of the four human organs, the small intestine displayed the highest activity towards both compounds. Collectively, these results imply that the sulfation mediated by SULT1A3 may play an important role in the metabolism and detoxification of ractopamine and salbutamol.

  19. 21 CFR 173.385 - Sodium methyl sulfate. (United States)


    ... Specific Usage Additives § 173.385 Sodium methyl sulfate. Sodium methyl sulfate may be present in pectin in accordance with the following conditions. (a) It is present as the result of methylation of pectin by....1 percent by weight of the pectin....

  20. Reductive and sorptive properties of sulfate green rust (GRSO4)

    DEFF Research Database (Denmark)

    Nedel, Sorin

    The Fe(II), Fe(III) hydroxide containing sulfate in its structure, called sulfate green rust (GRSO4), can effectively reduce and convert contaminants to less mobile and less toxic forms. However, the ability of GRSO4 to remove positively charged species from solution, via sorption, is very limited...