Sample records for aluminum ammonium sulfate

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.



  9. 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.

  10. 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

  11. 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

  12. 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).

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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...

  20. 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...

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  7. 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.

  8. 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.

  9. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  12. Comparative Evaluation of Aluminum Sulfate and Ferric Sulfate-Induced Coagulations as Pretreatment of Microfiltration for Treatment of Surface Water. (United States)

    Song, Yali; Dong, Bingzhi; Gao, Naiyun; Deng, Yang


    Two coagulants, aluminum sulfate and ferric chloride, were tested to reduce natural organic matter (NOM) as a pretreatment prior to polyvinylidene fluoride (PVDF) microfiltration (MF) membranes for potable water treatment. The results showed that the two coagulants exhibited different treatment performance in NOM removal. Molecular weight (MW) distributions of NOM in the tested surface raw water were concentrated at 3-5 kDa and approximately 0.2 kDa. Regardless of the coagulant species and dosages, the removal of 0.2 kDa NOM molecules was limited. In contrast, NOM at 3-5 kDa were readily removed with increasing coagulant dosages. In particular, aluminum sulfate favorably removed NOM near 5 kDa, whereas ferric chloride tended to reduce 3 kDa organic substances. Although aluminum sulfate and ferric chloride could improve the flux of the ensuing MF treatment, the optimal coagulant dosages to achieve effective pretreatment were different: 2-30 mg/L for aluminum sulfate and >15 mg/L for ferric chloride. The scanning electron microscope (SEM) image of the membrane-filtered coagulated raw water showed that coagulation efficiency dramatically affected membrane flux and that good coagulation properties can reduce membrane fouling.

  13. Comparative Evaluation of Aluminum Sulfate and Ferric Sulfate-Induced Coagulations as Pretreatment of Microfiltration for Treatment of Surface Water

    Directory of Open Access Journals (Sweden)

    Yali Song


    Full Text Available Two coagulants, aluminum sulfate and ferric chloride, were tested to reduce natural organic matter (NOM as a pretreatment prior to polyvinylidene fluoride (PVDF microfiltration (MF membranes for potable water treatment. The results showed that the two coagulants exhibited different treatment performance in NOM removal. Molecular weight (MW distributions of NOM in the tested surface raw water were concentrated at 3–5 kDa and approximately 0.2 kDa. Regardless of the coagulant species and dosages, the removal of 0.2 kDa NOM molecules was limited. In contrast, NOM at 3–5 kDa were readily removed with increasing coagulant dosages. In particular, aluminum sulfate favorably removed NOM near 5 kDa, whereas ferric chloride tended to reduce 3 kDa organic substances. Although aluminum sulfate and ferric chloride could improve the flux of the ensuing MF treatment, the optimal coagulant dosages to achieve effective pretreatment were different: 2–30 mg/L for aluminum sulfate and >15 mg/L for ferric chloride. The scanning electron microscope (SEM image of the membrane-filtered coagulated raw water showed that coagulation efficiency dramatically affected membrane flux and that good coagulation properties can reduce membrane fouling.

  14. Aluminum sulfate significantly reduces the skin test response to common allergens in sensitized patients

    Directory of Open Access Journals (Sweden)

    Grier Thomas J


    Full Text Available Abstract Background Avoidance of allergens is still recommended as the first and best way to prevent allergic illnesses and their comorbid diseases. Despite a variety of attempts there has been very limited success in the area of environmental control of allergic disease. Our objective was to identify a non-invasive, non-pharmacological method to reduce indoor allergen loads in atopic persons' homes and public environments. We employed a novel in vivo approach to examine the possibility of using aluminum sulfate to control environmental allergens. Methods Fifty skin test reactive patients were simultaneously skin tested with conventional test materials and the actions of the protein/glycoprotein modifier, aluminum sulfate. Common allergens, dog, cat, dust mite, Alternaria, and cockroach were used in the study. Results Skin test reactivity was significantly reduced by the modifier aluminum sulfate. Our studies demonstrate that the effects of histamine were not affected by the presence of aluminum sulfate. In fact, skin test reactivity was reduced independent of whether aluminum sulfate was present in the allergen test material or removed prior to testing, indicating that the allergens had in some way been inactivated. Conclusion Aluminum sulfate was found to reduce the in vivo allergic reaction cascade induced by skin testing with common allergens. The exact mechanism is not clear but appears to involve the alteration of IgE-binding epitopes on the allergen. Our results indicate that it may be possible to diminish the allergenicity of an environment by application of the active agent aluminum sulfate, thus producing environmental control without complete removal of the allergen.

  15. 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

  16. 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.

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. 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

  2. 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

  3. 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.

  4. 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

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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

  19. Simulation of detonation of ammonium nitrate fuel oil mixture confined by aluminum: edge angles for DSD

    Energy Technology Data Exchange (ETDEWEB)

    Short, Mark [Los Alamos National Laboratory; Quirk, James J [Los Alamos National Laboratory; Kiyanda, Charles B [Los Alamos National Laboratory; Jackson, Scott I [Los Alamos National Laboratory; Briggs, Matthew E [Los Alamos National Laboratory; Shinas, Micheal A [Los Alamos National Laboratory


    Non-ideal high explosives are typically porous, low-density materials with a low detonation velocity (3--5 km/s) and long detonation reaction zone ({approx} cms). As a result, the interaction of a non-ideal high explosive with an inert confiner can be markedly different than for a conventional high explosive. Issues arise, for example, with light stiff confiners where the confiner can drive the high explosive (HE) through a Prandtl-Meyer fan at the HE/confiner interface rather than the HE driving the confiner. For a non-ideal high explosive confined by a high sound speed inert such that the detonation velocity is lower than the inert sound speed, the flow is subsonic and thus shockless in the confiner. In such cases, the standard detonation shock dynamics methodology, which requires a positive edge-angle be specified at the HE/confiner interface in order that the detonation shape be divergent, cannot be directly utilized. In order to study how detonation shock dynamics can be utilized in such cases, numerical simulations of the detonation of ammonium nitrate-fuel oil (ANFO) confined by aluminum 6061 are conducted.

  20. Study on Properties and Synthesize of a new Polymeric Aluminum Sulfate-silicate

    Institute of Scientific and Technical Information of China (English)

    Yu Shu-rong; Wang Qing-ning; Zhang Fei-long; Ye Qi-zhi


    The polymeric basic aluminum silicate-sulfate can be made from three substances, such as aluminum sulfate, sodium silicate and sodium aluminates. Adoption sort neote ric one synthesis,under high shear mixing condition to produce polymeric Aluminum Sulfate-silicate--inorganic macromolecule flocculants, that is liquid, PH is 3.0, molecular formula: AlA (OH) B (SO4) C (SiOx)Because inorganic macromolecule have capability of electricity neutralized, bigger molecular mass,strong capability of adsorption, and products are relative stabilize, more economical than organic macromolecule flocculants, innocuity and high effect compared with tradition flocculants.We can use the flocculants to make sewages purified .The sewages contain sulfur, oiliness, which are treated sewages of oil refining to organism treatment sump in parturition course of oil refining,and the sewages of dark and white in parturition course of paper mill. We study the properties of the flocculants, change of CODCr and effect of sewerage decolouring and so on.Thus fig. Can be seen to add the flocculants(0.1ml) to the sewages of the oil refining and the paper mill that effect is not distinctly. Yet increase of quantity to remove turbidity and floccules effect is distinctness. When the flocculants (0.5mi) be added to the dark sewage of, the penetrate light rate attain 90~98%, the sewage of the oil refining is about 90%, but when we make floccules experiment, the color of dark green and auras of the sewages of oil refining and the paper mill are all disappear, the PASS that add to the sewage will have certainly time to flocculate. When use pay attention to quantity and horary the connection.As a result in the sewages purified, those products form quickly, granule density is big, and subsided velocity is quickly, Floccules effect and capability of removing turbidity, removing CODCr are ascendancy than tradition flocculants - aluminates, and the remained aluminum of water treatment is little. It has

  1. 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

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. {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)

  7. 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.

  8. Understanding pH and ionic strength effects on aluminum sulfate-induced microalgae flocculation. (United States)

    Cui, Y; Yuan, W; Cheng, J


    The objective of this study was to understand the effect of pH and ionic strength of aluminum sulfate on the flocculation of microalgae. It was found that changing pH and ionic strength influenced algal flocculation by changing the zeta potential of cells, which was described by the classical theory of Derjaguin, Landau, Verwey, and Overbeek (DLVO). For both algal species of Scenedesmus dimorphus and Nannochloropsis oculata, cells with lower total DLVO interaction energy had higher flocculation efficiency, indicating that the DLVO model was qualitatively accurate in predicting the flocculation of the two algae. However, the two algae responded differently to changing pH and ionic strength. The flocculation of N. oculata increased with increasing aluminum sulfate concentration and favored either low (pH 5) or high (pH 10) pH where cells had relatively low negative surface charges. For S. dimorphus, the highest flocculation was achieved at low ionic strength (1 μM) or moderate pH (pH 7.5) where cell surface charges were fully neutralized (zero zeta potential).

  9. 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.

  10. 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.

  11. 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.

  12. [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.

  13. 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.

  14. Toxicity detection of sodium nitrite, borax and aluminum potassium sulfate using electrochemical method

    Institute of Scientific and Technical Information of China (English)

    Dengbin Yu; Daming Yong; Shaojun Dong


    Based on the inhibition effect on the respiratory chain activity of microorganisms by toxicants,an electrochemical method has been developed to measure the current variation of a mediator in the presence of microorganisms contacted with a toxicant.Microelectrode arrays were adopted in this study,which can accelerate the mass transfer rate of an analyte to the electrode and also increase the total current signal,resulting in an improvement in detection sensitivity.We selected Escherichia coli as the testee and the standard glucoseglutamic acid as an exogenous material.Under oxygen restriction,the experiments in the presence of toxicant were performed at optimum conditions (solution pH 7.0,37℃ and reaction for 3 hr).The resulting solution was then separated from the suspended microorganisms and was measured by an electrochemical method,using ferricyanide as a mediator.The current signal obtained represents the re oxidation of ferrocyanide,which was transformed to inhibiting efficiency,IC50,as a quantitative measure of toxicity.The IC50 values measured were 410,570 and 830 mg/L for sodium nitrite,borax and aluminum potassium sulfate,respectively.The results show that the toxicity sequence for these three food additives is consistent with the value reported by other methods.Furthermore,the order of damage degree to the microorganism was also observed to be:sodium nitrite > borax > aluminum potassium sulfate >blank,according to the atomic force microscopy images of E.coli after being incubated for 3 hr with the toxic compound in buffer solutions.The electrochemical method is expected to be a sensitive and simple alternative to toxicity screening for chemical food additives.

  15. 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).

  16. DNA damage in the kidney tissue cells of the fish Rhamdia quelen after trophic contamination with aluminum sulfate

    Directory of Open Access Journals (Sweden)

    Tatiane Klingelfus


    Full Text Available Abstract Even though aluminum is the third most common element present in the earth's crust, information regarding its toxicity remains scarce. It is known that in certain cases, aluminum is neurotoxic, but its effect in other tissues is unknown. The aim of this work was to analyze the genotoxic potential of aluminum sulfate in kidney tissue of the fish Rhamdia quelen after trophic contamination for 60 days. Sixty four fish were subdivided into the following groups: negative control, 5 mg, 50 mg and 500 mg of aluminum sulfate per kg of fish. Samples of the posterior kidney were taken and prepared to obtain mitotic metaphase, as well as the comet assay. The three types of chromosomal abnormalities (CA found were categorized as chromatid breaks, decondensation of telomeric region, and early separation of sister chromatids. The tests for CA showed that the 5 mg/kg and 50 mg/kg doses of aluminum sulfate had genotoxic potential. Under these treatments, early separation of the sister chromatids was observed more frequently and decondensation of the telomeric region tended to increase in frequency. We suggest that structural changes in the proteins involved in DNA compaction may have led to the decondensation of the telomeric region, making the DNA susceptible to breaks. Moreover, early separation of the sister chromatids may have occurred due to changes in the mobility of chromosomes or proteins that keep the sister chromatids together. The comet assay confirmed the genotoxicity of aluminum sulfate in the kidney tissue of Rhamdia quelen at the three doses of exposure.

  17. Effects of aluminum sulfate on delta-aminolevulinate dehydratase from kidney, brain, and liver of adult mice

    Directory of Open Access Journals (Sweden)

    Schetinger M.R.C.


    Full Text Available The purpose of the present study was to investigate the in vitro and in vivo effects of aluminum sulfate on delta-aminolevulinic acid dehydratase (ALA-D activity from the brain, liver and kidney of adult mice (Swiss albine. In vitro experiments showed that the aluminum sulfate concentration needed to inhibit the enzyme activity was 1.0-5.0 mM (N = 3 in brain, 4.0-5.0 mM (N = 3 in liver and 0.0-5.0 mM (N = 3 in kidney. The in vivo experiments were performed on three groups for one month: 1 control animals (N = 8; 2 animals treated with 1 g% (34 mM sodium citrate (N = 8 and 3 animals treated with 1 g% (34 mM sodium citrate plus 3.3 g% (49.5 mM aluminum sulfate (N = 8. Exposure to aluminum sulfate in drinking water inhibited ALA-D activity in kidney (23.3 ± 3.7%, mean ± SEM, P<0.05 compared to control, but enhanced it in liver (31.2 ± 15.0%, mean ± SEM, P<0.05. The concentrations of aluminum in the brain, liver and kidney of adult mice were determined by graphite furnace atomic absorption spectrometry. The aluminum concentrations increased significantly in the liver (527 ± 3.9%, mean ± SEM, P<0.05 and kidney (283 ± 1.7%, mean ± SEM, P<0.05 but did not change in the brain of aluminum-exposed mice. One of the most important and striking observations was the increase in hepatic aluminum concentration in the mice treated only with 1 g% sodium citrate (34 mM (217 ± 1.5%, mean ± SEM, P<0.05 compared to control. These results show that aluminum interferes with delta-aminolevulinate dehydratase activity in vitro and in vivo. The accumulation of this element was in the order: liver > kidney > brain. Furthermore, aluminum had only inhibitory properties in vitro, while in vivo it inhibited or stimulated the enzyme depending on the organ studied.

  18. 由废铝制备明矾及其组成测定%Preparation and determination of potassium aluminum sulfate from waste aluminum

    Institute of Scientific and Technical Information of China (English)



    以生活废铝易拉罐为原料,采用不同的方法制备明矾,通过XRD、TG、EDTA配位法、重量法等对产物进行了表征,获得了很好的结果.%Potassium aluminum sulfate were prepared by different ways used pop can as material, the complexes were characterized by XRD,TG and EDTA coordination and weight method, and the result is satisfying.

  19. 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.

  20. 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).

  1. 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。

  2. 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.

  3. 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.

  4. 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.

  5. Comparative study between M. oleifera and aluminum sulfate for water treatment: case study Colombia. (United States)

    Salazar Gámez, Lorena L; Luna-delRisco, Mario; Cano, Roberto Efrain Salazar


    The world has a water deficit, mostly located in developing countries. For example, in Colombia, water deficit is a major concern and it increases in rural areas, where the rate of accessibility to drinking water is of 33.26% in 2005. Since the 1970s, the most used technology for water purification is the conventional physicochemical process. The most common coagulant used in this process is aluminum sulfate (alum). This study focuses on a comparison between Moringa oleifera seeds and alum for water treatment in different natural waters. Results showed that M. oleifera removed 90% turbidity and alum 96% from water samples from the tested natural brook. However, color removal for M. oleifera was 95 and 80.3% for alum. For water-polluted samples, both coagulants have shown high efficiency (100%) in color and turbidity removal. Usage of natural coagulants (i.e., M. oleifera) instead of chemical ones (i.e., alum) are more convenient in rural areas where the economic situation and accessibility of those products are key elements to maintain fresh water treatment standards. Additionally, results demonstrated that high dosages M. oleifera did not affect the optimal value in terms of color and turbidity removal. In rural and developing countries, this is important because it does not require a sophisticated dosing equipment.

  6. Eliminating aluminum toxicity in an acid sulfate soil for rice cultivation using plant growth promoting bacteria. (United States)

    Panhwar, Qurban Ali; Naher, Umme Aminun; Radziah, Othman; Shamshuddin, Jusop; Razi, Ismail Mohd


    Aluminum toxicity is widely considered as the most important limiting factor for plants growing in acid sulfate soils. A study was conducted in laboratory and in field to ameliorate Al toxicity using plant growth promoting bacteria (PGPB), ground magnesium limestone (GML) and ground basalt. Five-day-old rice seedlings were inoculated by Bacillus sp., Stenotrophomonas maltophila, Burkholderia thailandensis and Burkholderia seminalis and grown for 21 days in Hoagland solution (pH 4.0) at various Al concentrations (0, 50 and 100 μM). Toxicity symptoms in root and leaf were studied using scanning electron microscope. In the field, biofertilizer (PGPB), GML and basalt were applied (4 t·ha-1 each). Results showed that Al severely affected the growth of rice. At high concentrations, the root surface was ruptured, leading to cell collapse; however, no damages were observed in the PGPB inoculated seedlings. After 21 days of inoculation, solution pH increased to >6.0, while the control treatment remained same. Field study showed that the highest rice growth and yield were obtained in the bio-fertilizer and GML treatments. This study showed that Al toxicity was reduced by PGPB via production of organic acids that were able to chelate the Al and the production of polysaccharides that increased solution pH. The release of phytohormones further enhanced rice growth that resulted in yield increase.

  7. Investigation of ozone and coagulant material’s (aluminum sulfate, ferric chloride, poly aluminum chloride and lime efficiency in “Kerman Kork” industry wastewater treatment

    Directory of Open Access Journals (Sweden)

    Amir Hussein Javid


    Full Text Available Background: Entry of untreated wastewater of wool scouring factories has been associated with many environmental hazards because of high rate of pollution. Presently effective treatment methods and reducing the costs of operation and maintenance from treatment units have always been under the attention of this industry owners. The aim of this survey is to present a suitable method for the treatment of wool scouring. Methods: In this study, chemical coagulant is used for wastewater treatment (aluminum sulfate, ferric chloride, poly aluminum chloride and lime. And then these materials with “ozone” as a strong oxidative in reduction of the amount of Chemical Oxygen Demand (COD in wastewater effluent has been surveyed. Results: The results of this work showed that only ferric chloride and aluminum sulfate among the above chemical coagulant had a high efficiency in the turbidity removal. Productivity of turbidity removal using ferric chloride with the pH of 4 to 5 was 99%, and turbidity was reduced from 166 Nephelometric Turbidity Units (NTU to 1.5 NTU, and productivity of turbidity removal using aluminum sulfate within the pH 4.5 to 5 was 99.33% that reduced turbidity from 166 to 1.1 NTU. Results of ozonation with 5 g/hour and the oxygen flow of 2.5 litter per min with the pH assess of 15, 30, 45, 60, 90, 120, and 150 min to wastewater from chemical treatment with ferric chloride showed that the rate of COD was reduced from 24700 mg/L to 2940 mg/L. In ozonation to wastewater of chemical treatment with aluminum sulfate within the above rang of time, the rate of COD was reduced from 22500 mg/l to 4800 mg/l. Conclusion: We can be hopeful that in near future, getting the cheap technology of ozone production in industrial scale, one can use this technology for the propose of removal of pollutants having removal preferable by help of advanced treatment approaches.

  8. 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.

  9. Experimental Study on the Feasibility of Using Water Glass and Aluminum Sulfate to Treat Complications in High Liquid Limit Soil Subgrade



    The feasibility of using water glass and aluminum sulfate to treat high liquid limit soil subgrade diseases is studied through laboratory experiments, and the following results were observed. After improving the high liquid limit clay with water glass and aluminum sulfate, the liquid limit decreases, the plastic limit increases, and the plasticity index decreases. Compared with untreated soil, the clay content of the improved soil decreases, while the silt and coarse contents increase. The ab...

  10. 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.

  11. 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.

  12. 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.

  13. 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...

  14. 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.

  15. 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.

  16. Comparative toxicities of aluminum and zinc from sacrificial anodes or from sulfate salt in sea urchin embryos and sperm. (United States)

    Caplat, Christelle; Oral, Rahime; Mahaut, Marie-Laure; Mao, Andrea; Barillier, Daniel; Guida, Marco; Della Rocca, Claudio; Pagano, Giovanni


    The toxicity of aluminum or zinc from either sacrificial anodes (SA) or their sulfate salts (SS) was evaluated in sea urchin (Paracentrotus lividus) embryos or sperm exposed to Al(III) or Zn(II) (SA or SS, 0.1-10 microM), scoring developmental defects (DDs), fertilization rate (FR), and mitotic abnormalities. A significant DD increase was observed in SS, but not SA Al(III)- and Zn(II)-exposed embryos vs. controls. Both Al(III) and Zn(II), up to 10 microM, from SA and SS, inhibited mitotic activity and induced mitotic aberrations in exposed embryos. SA-Al(III)-exposed sperm displayed a significant FR increase, unlike Al(III) sulfate overlapping with controls. Both SA-Zn(II) and Zn(II) sulfate sperm exposure resulted in a significant FR increase. The offspring of SA-Al(III)-exposed sperm displayed a significant DD decrease, unlike Al(III) sulfate exposure. Zinc sulfate sperm exposure resulted in a significant increase in offspring DDs, whereas SA-Zn(II) sperm exposure decreased DDs. Together, exposures to SA-dissolved Al(III) or Zn(II) resulted in lesser, if any toxicity, up to hormesis, compared to SS. Studies of metal speciation should elucidate the present results.

  17. Evaluation of using aluminum sulfate and water-soluble Moringa oleifera seed lectin to reduce turbidity and toxicity of polluted stream water. (United States)

    Freitas, José Henrique Edmilson Souza; de Santana, Keissy Vanderley; do Nascimento, Ana Cláudia Claudina; de Paiva, Sérgio Carvalho; de Moura, Maiara Celine; Coelho, Luana Cassandra Breitenbach Barroso; de Oliveira, Maria Betânia Melo; Paiva, Patrícia Maria Guedes; do Nascimento, Aline Elesbão; Napoleão, Thiago Henrique


    Aluminum salts are used as coagulants in water treatment; however, the exposure to residual aluminum has been associated with human brain lesions. The water-soluble Moringa oleifera lectin (WSMoL), which is extracted with distilled water and isolated by chitin chromatography, has coagulant activity and is able to reduce the concentration of metal ions in aqueous solutions. This study evaluated the potential of using aluminum sulfate and WSMoL to reduce the turbidity and toxicity of water from the Cavouco stream located in Recife, Pernambuco, Brazil. The water sample used (called P1) was collected from the stream source, which was found to be strongly polluted based on physicochemical and water quality analyses, as well as ecotoxicity assays with Artemia salina and seeds of Eruca sativa and Lactuca sativa. The assays combining WSMoL and aluminum sulfate were more efficient than those that used these agents separately. Furthermore, the greatest reduction in turbidity (96.8%) was obtained with the treatment using aluminum sulfate followed by WSMoL, compared to when they were applied simultaneously (91.3%). In addition, aluminum sulfate followed by WSMoL treatment resulted in residual aluminum concentration (0.3 mg/L) that was much lower than that recorded after the treatment using only the salt (35.5 mg/L). The ecotoxicity of P1 was also strongly reduced after the treatments. In summary, the combined use of aluminum sulfate and WSMoL was efficient in promoting a strong reduction of turbidity and ecotoxicity of a polluted water sample, without resulting in a high residual aluminum concentration at the conclusion of the treatment.

  18. 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。

  19. 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%.

  20. 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.

  1. 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.

  2. 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.

  3. 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

  4. Study on the Synthesis of Nano Ammonium Aluminum Carbonate Hydroxide (AACH)%纳米碳酸铝铵前驱体制备的研究

    Institute of Scientific and Technical Information of China (English)

    王伟礼; 毕见强; 邢政


    以硫酸铝铵(NH4Al(SO4)2)和碳酸氢铵(NH4HCO3)为主要原料,采用沉淀法制备纳米碳酸铝铵(AACH)前驱体,并利用X射线衍射(XRD),透射电镜(TEM)对前驱体的物相和形貌进行表征.研究表明,滴定速度和陈化时间对前驱体的形貌略有影响,而滴定方式和pH值对其影响较大.将硫酸铝铵溶液滴入碳酸氢铵溶液中,调节体系的pH值9-10,并将其陈化12小时,可以得到较好的前驱体.%Ammonium aluminum carbonate hydroxide (AACH) nanopowder was prepared via a precipitation reaction between ammonium aluminum sulphate (NH4 Al(SO4)2) and ammonium hydrogen carbonate (NH4 HCO3) in different conditions.The precursors were characterized by X-ray diffraction (XRD),transmission electron microscopy (TEM).The results show that titration rate and aging time affected the morphology of precursors a bit,and titration mode and pH value affected the composition of precursors greatly.The optimum process was that NH4 Al(SO4)2 solution was added into NH4 HCO3 solution at pH 9-10 with aging time of 12h.

  5. Investigation of dynamic processing on aluminum floc aggregation: Cyclic shearing recovery and effect of sulfate ion

    Institute of Scientific and Technical Information of China (English)

    CHU YongBao; GAO BaoYu; YUE QinYan; WANG Yan


    The floe formation and re-aggregation potential and the effects of sulfate on coagulation by AlCl3, polyaluminum chloride (PAC), and Al13 species using a photometric dispersion analyzer (PDA) are in-vestigated. It is found that the recovery level from shearing is the highest for the Al13 species. This is likely s result of Increased collision efficiency due to more effective charge neutralization. The ex-perimental results show that sulfate has a significant effect on coagulation and promoting aggregation of hydrolyzed specie8 for the Al13 species. It results in significant improvement of the coagulation effi-ciency through an electrostatic patch effect. The results further indicate that zeta potential of the psrti-cle suspension is not the only indicator for the coagulant efficiency when preoipitate formation sig-nificantly Improves coagulation.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. Modulation of tumor necrosis factor {alpha} expression in mouse brain after exposure to aluminum in drinking water

    Energy Technology Data Exchange (ETDEWEB)

    Tsunoda, M.; Sharma, R.P. [Georgia Univ., Athens (Greece). College of Veterinary Medicine


    Aluminum, a known neurotoxic substance and a ground-water pollutant, is a possible contributing factor in various nervous disorders including Alzheimer's disease. It has been hypothesized that cytokines are involved in aluminum neurotoxicity. We investigated the alterations in mRNA expression of tumor necrosis factor {alpha} (TNF{alpha}), interleukin-1{beta} (IL-1{beta}), and interferon {gamma} (IFN{gamma}), cytokines related to neuronal damage, in cerebrum and peripheral immune cells of mice after exposure to aluminum through drinking water. Groups of male BALB/c mice were administered aluminum ammonium sulfate in drinking water ad libitum at 0, 5, 25, and 125 ppm aluminum for 1 month. An additional group received 250 ppm ammonium as ammonium sulfate. After treatment, the cerebrum, splenic macrophages and lymphocytes were collected. The expression of TNF{alpha} mRNA in cerebrum was significantly increased among aluminum-treated groups compared with the control, in a dose-dependent manner. Other cytokines did not show any aluminum-related effects. In peripheral cells, there were no significant differences of cytokine mRNA expressions among treatment groups. Increased expression of TNF{alpha} mRNA by aluminum in cerebrum may reflect activation of microglia, a major source of TNF{alpha} in this brain region. Because the aluminum-induced alteration in cytokine message occurred at aluminum concentrations similar to those noted in contaminated water, these results may be relevant in considering the risk of aluminum neurotoxicity in drinking water. (orig.)

  11. Experimental observations of detonation in ammonium-nitrate-fuel-oil (ANFO) surrounded by a high-sound speed, shockless, aluminum confiner

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, Scott I [Los Alamos National Laboratory; Klyanda, Charles B [Los Alamos National Laboratory; Short, Mark [Los Alamos National Laboratory


    Detonations in explosive mixtures of ammonium-nitrate-fuel-oil (ANFO) confined by aluminum allow for transport of detonation energy ahead of the detonation front due to the aluminum sound speed exceeding the detonation velocity. The net effect of this energy transport on the detonation is unclear. It could enhance the detonation by precompressing the explosive near the wall. Alternatively, it could desensitize the explosive by crushing porosity required for shock initiation or destroying confinement ahead of the detonation. As these phenomena are not well understood, most numerical explosive models are unable to account for them. But with slowly detonating, non-ideal high explosive (NIHE) systems becoming increasing prevalent, proper understanding and prediction of the performance of these metal-confined NIHE systems is desirable. Experiments are discussed that measured the effect of this ANFO detonation energy transported upstream of the front by an aluminum confining tube. Detonation velocity, detonation front curvature, and aluminum response are recorded as a function of confiner wall thickness and length. Front curvature profiles display detonation acceleration near the confining surface, which is attributed to energy transported upstream modifying the flow. Average detonation velocities were seen to increase with increasing confiner thickness due to the additional inertial confinement of the reaction zone flow. Significant radial sidewall tube motion was observed immediately ahead of the detonation. Axial motion was also detected which interfered with the front curvature measurements in some cases. It was concluded that the confiner was able to transport energy ahead of the detonation and that this transport has a definite effect on the detonation.

  12. 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.

  13. 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.

  14. Experimental Study on the Feasibility of Using Water Glass and Aluminum Sulfate to Treat Complications in High Liquid Limit Soil Subgrade

    Directory of Open Access Journals (Sweden)

    Wen-hui Zhang


    Full Text Available The feasibility of using water glass and aluminum sulfate to treat high liquid limit soil subgrade diseases is studied through laboratory experiments, and the following results were observed. After improving the high liquid limit clay with water glass and aluminum sulfate, the liquid limit decreases, the plastic limit increases, and the plasticity index decreases. Compared with untreated soil, the clay content of the improved soil decreases, while the silt and coarse contents increase. The absolute and relative expansion rates of the improved soil are both lower than those of the untreated soil. With the same number of dry and wet cycles, the decreased degrees of cohesion and internal friction angle of the improved soil are, respectively, one-half and one-third of those of the untreated soil. After three dry and wet cycles, the California bearing ratio (CBR of the untreated soil does not meet the requirements of specifications. However, after being cured for seven days and being subjected to three dry and wet cycles, the CBR of the improved soil, with 4% water glass solution and 0.4% aluminum sulfate, meets the requirements of specifications.

  15. 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.

  16. On the crucial influence of some supporting electrolytes during electrocoagulation in the presence of aluminum electrodes


    Trompette, Jean-Luc; Vergnes, Hugues


    The influence of some supporting electrolytes on aluminum electrode oxidation and pH variation during electrocoagulation of an unskimmed milk sample and a cutting oil emulsion has been investigated. Among the electrolytes studied, sulfate anions were found to be quite harmful both for electrical consumption and electrocoagulation efficiency. At the opposite, chloride and ammonium ionswere particularly benefic respectively for aluminum corrosion and pH regulation, whereas sodium cations were o...

  17. 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.

  18. 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.

  19. 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。

  20. 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.

  1. 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).

  3. 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%.

  4. On the crucial influence of some supporting electrolytes during electrocoagulation in the presence of aluminum electrodes. (United States)

    Trompette, J L; Vergnes, H


    The influence of some supporting electrolytes on aluminum electrode oxidation and pH variation during electrocoagulation of an unskimmed milk sample and a cutting oil emulsion has been investigated. Among the electrolytes studied, sulfate anions were found to be quite harmful both for electrical consumption and electrocoagulation efficiency. At the opposite, chloride and ammonium ions were particularly benefic respectively for aluminum corrosion and pH regulation, whereas sodium cations were observed to have a neutral role. The results indicate that electrocoagulation can be realized at low anodic potential even in the presence of sulfate ions when the [Cl(-)]/[SO(4)(2-)] ratio is around or greater than 1/10. The detrimental effect of sulfates on electrocoagulation efficiency can be thwarted by the use of the ammonium salt thanks to its related buffer effect.

  5. 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.

  6. 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。

  7. 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)

  8. Investigation of dynamic processing on aluminum floc aggregation:Cyclic shearing recovery and effect of sulfate ion

    Institute of Scientific and Technical Information of China (English)


    The floc formation and re-aggregation potential and the effects of sulfate on coagulation by AlCl3, polyaluminum chloride (PAC), and Al13 species using a photometric dispersion analyzer (PDA) are in- vestigated. It is found that the recovery level from shearing is the highest for the Al13 species. This is likely a result of increased collision efficiency due to more effective charge neutralization. The ex- perimental results show that sulfate has a significant effect on coagulation and promoting aggregation of hydrolyzed species for the Al13 species. It results in significant improvement of the coagulation effi- ciency through an electrostatic patch effect. The results further indicate that zeta potential of the parti- cle suspension is not the only indicator for the coagulant efficiency when precipitate formation sig- nificantly improves coagulation.


    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...

  10. 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

  11. 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.

  12. 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。

  13. 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

  14. [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.


    Institute of Scientific and Technical Information of China (English)

    Yu-sheng Qin; Xian-hong Wang; Xiao-jiang Zhao; Fo-song Wang


    Chloro(5,10,15,20-tetraphenyl-porphyrinato)-aluminum/tetraethylammonium bromide (Et4NBr) in combinationwith bulky Lewis acid was used for the copolymerization of CO2 and cyclohexene oxide (CHO). Bulky Lewis acid havingsubstituents at the ortho positions of the phenolate ligands, like methylaluminum bis(2,6-di-tert-butyl-4-methylphenolate),significantly shortened the induction period and raised the catalytic activity, the corresponding turnover frequency reached44.9 h-1 in 9 h, which was 23.8% higher than that from (TPP)AICI/EtaNBr binary catalyst. The resulting polycarbonate hascarbonate linkage over 93% with number average molecular weight of (4.5-6.5)×103 and polydispersity index below 1.10.

  16. 硫酸铝改良苏打盐碱土后各离子的变化%The Change of Adding Aluminum Sulfate on Saline Alkali Soil's Ion

    Institute of Scientific and Technical Information of China (English)

    孙宇男; 耿玉辉; 赵兰坡


    为了更好地利用苏打盐碱土,对其进行更好地开发和改良,通过室内模拟,分析施用不同含量硫酸铝对土壤中可溶性盐及pH的影响.结果表明,添加硫酸铝后,使土壤溶液中钠离子、碳酸根和碳酸氢根明显增加,土壤溶液pH值明显下降,土壤性质明显改善.随着硫酸铝的增加,土壤颗粒释放出的可溶性盐也大量增加,明显减少土壤中的盐类物质.在加入不同浓度硫酸铝和不同淋洗次数的比较后,淋洗次数对苏打盐碱土中的盐类也有明显的影响,综合多项指标,加入硫酸铝浓度为0.8%时,淋洗2次,效果最佳.同时,苏打盐碱土理化性质的改良也为作物生长创造了良好的土壤环境.%In order to make better use of saline alkali soil, it should have better improvement. In this paper, effect of different concentrations of aluminum sulfate on soluble salts and pH value of the soil was studied through indoor simulation experiments. The results indicated that after a table 1 aluminum sulfate, Na+, CO32-and HCO3- contents of the soil solutions increased significantly, pH value of the soil solutions decreased significantly and properties of the soil had remarkable improvement. With the aluminum sulfate amount increasing, the soluble salt contents released from the soil particles increased, the salt contents in the soil reduced. Different density and washed times of aluminum sulfate influenced the outcome. At the same time, the improvement of physics-chemical properties of soda alkali-saline soils had created the good soil environment for the crops growth.

  17. EDTA complexometric titration for determination of aluminum in copper sulfate waste solution%EDTA 络合滴定法测定硫酸铜废液中的铝

    Institute of Scientific and Technical Information of China (English)

    白小叶; 迟爱玲


    Copper sulfate waste solution generated in metallurgical process is studied in determining aluminum . Ammonia (1+1) is used to separate aluminum in the form of aluminum hydroxide precipitation from the principal part of the solution ,and then the aluminum mass concentration is determined by EDTA complexometry .A series of ex-periments are conducted on the parameters such as copper and iron ionic interference ,solution acidity and the temper-ature of the EDTA complexation reaction ,solving the problems of the determination of the aluminum in this copper sul-fate waste solution .This method compared with spectrophotometry is simple , rapid and has lower analysis cost .The method through the determination in copper sulfate solution with different mass fraction ,obtains a relative standard de-viation of 0.071 %-0.930 %(n=6),and sample measurements are consistent with the azure S value determined by spectrophotometry .%实验研究了冶金工艺过程产生的硫酸铜废液中铝的测定方法。采用氨水(1+1)使铝以氢氧化铝沉淀的形式与主体溶液分离,然后用EDTA络合法测定铝的质量浓度;对该硫酸铜废液中铜、铁干扰离子、溶液的酸度、EDTA络合反应温度等条件进行了一系列的实验,解决了硫酸铜废液中铝的测定难题。该方法与分光光度法比较,简单快速,分析成本低廉;通过对不同硫酸铜废液中铝的质量浓度测定,相对标准偏差为0.071%~0.930%(n=6),样品测定值与络天青S分光光度法测定值相符合。

  18. (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.

  19. 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.

  20. Microemulsion-assisted synthesis of mesoporous aluminum oxyhydroxide nanoflakes for efficient removal of gaseous formaldehyde. (United States)

    Xu, Zhihua; Yu, Jiaguo; Low, Jingxiang; Jaroniec, Mietek


    Mesoporous aluminum oxyhydroxides composed of nanoflakes were prepared via a water-in-oil microemulsion-assisted hydrothermal process at 50 °C using aluminum salts as precursors and ammonium hydroxide as a precipitating agent. The microstructure, morphology, and textural properties of the as-prepared materials were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), nitrogen adsorption, and X-ray photoelectron spectroscopy (XPS) techniques. It is shown that the aluminum oxyhydroxide nanostructures studied are effective adsorbents for removal of formaldehyde (HCHO) at ambient temperature, due to the abundance of surface hydroxyl groups, large specific surface area, and suitable pore size. Also, the type of aluminum precursor was essential for the microstructure formation and adsorption performance of the resulting materials. Namely, the sample prepared from aluminum sulfate (Al-s) exhibited a relatively high HCHO adsorption capacity in the first run, while the samples obtained from aluminum nitrate (Al-n) and chloride (Al-c) exhibited high adsorption capacity and relatively stable recyclability. A combination of high surface area and strong surface affinity of the prepared aluminum oxyhydroxide make this material a promising HCHO adsorbent for indoor air purification.

  1. 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。

  2. 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

  3. 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)

  4. 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%。

  5. 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.

  6. 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.

  7. 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

  8. 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)

  9. 秸秆碳和硫酸铝对富营养化水体中氮磷的吸收去除效应及其影响因素%Adsorption and Removal of Nitrogen and Phosphorus from Eutrophic Water by Straw Carbon and Aluminum Sulfate and Influencing Factors

    Institute of Scientific and Technical Information of China (English)

    王爽; 赵兰坡


    In order to solve the problem of eutrophication in China, straw carbon and aluminum sulfate as an effective adsorbent used to absorption of total phosphorus and total nitrogen in water. Through the laboratory simulation test,by equilibrium adsorption method, the author investigated the effect on the adsorption under different environmental factors as the dosage of aluminum sulfate, pH, shaking time, temperature, disturbance, straw carbon size and so on. The results showed that with the dosage of aluminum sulfate and straw carbon was 0. 2 mg/L,the shock time was 120 min, the best adsorption of the removal rate could reach 80% or more. Among different factors, aluminum sulfate and straw carbon the tatal phosphorus and nitrogen of adsorption analysis indicated that adding an appropriate amount of aluminum sulfate and straw carbon could reduce the total nitrogen and total phosphorus content in water, the adsorption on temperature, pH, shock time was sensitive. That was to provide a favorable basis for solving the problem of water environment in China.%为解决中国水体富营养化问题,将秸秆碳与硫酸铝作为一种有效吸附水体中总氮,总磷的吸附剂,通过室内模拟试验,采用平衡吸附法,考察了秸秆碳和硫酸铝投加量、pH值、振荡时间、温度、扰动、秸秆碳粒径等不同环境因素条件下对吸附效果的影响.结果表明:在秸秆碳和硫酸铝投加量为0.2 mg/L、振荡时间为120 min的条件下,吸附效果最好,去除率可达80%以上.通过对各因素与秸秆碳、硫酸铝对总氮和总磷的吸附效果分析得知,加入适量的秸秆碳和硫酸铝,可以降低水体中总氮、总磷的含量,吸附效果对温度、振荡时间、pH值变化敏感,这也为解决水体富营养化问题提供了基础依据.

  10. 不同硫酸铝施用条件下对苏打盐碱地水稻吸肥规律的研究%Research on Soda Saline-Alkali Soil Rice Absorb Fertilizer Rule in Conditions of Different Aluminum Sulfate Apply

    Institute of Scientific and Technical Information of China (English)

    马巍; 王鸿斌; 赵兰坡


    The text of soda saline-alkali soil rice apply to the improvement of aluminum sulfate which the study, the effects of the different aluminum sulfate use level to rice absorb N, P and K nutritional and rice production. The experiment results showed that the soda saline-alkali in the rice fields which to apply for aluminum sulfate, rice absorbing capacity of the N, P and K fertilizer increased. The P increased the most obvious. The maximum value of rice absorbed N and P content in the mature period. There was no laws about the different to use level of aluminum sulfate to rice absorb nutrition. In the condition of aluminum sulfate used level for 300 kg/hm2, the rice production highest. The soda saline-alkali soil provided for fertilizer a low ability. In this fertilizer nitrogen the time was to improve the utilization rate apply to the important measures to increase the output was also an important guarantee. Aluminum sulfate application of increase apparent P recovery rates. In the rice grown in soda saline-alkali soil attention should be improved with aluminum sulfate reasonable application and strengthen the effectiveness of the study in the future.%通过对苏打盐碱地水稻施用硫酸铝改良剂的研究,阐明了不同硫酸铝施用量对水稻氮、磷、钾素营养吸收及产量的影响.试验结果表明,在重度盐碱化稻田上,施用硫酸铝可使水稻对氮、磷、钾的吸收量增加,水稻吸收养分能力分别提高40%、100%、40%.吸磷量增加最明显.其中吸氮量、吸磷量最大值均出现在成熟期.不同硫酸铝施用量对水稻吸收养分的影响无规律性.但在硫酸铝施用量为300kg/hm2的情况下,水稻产量可较不施用硫酸铝处理增加近8倍,是盐碱地水稻产量最大时硫酸铝的施用量.盐碱地稻田土壤供肥能力较低,氮肥分次施用是提高其利用率的重要措施,也是提高产量的重要保障.硫酸铝的施用提高了磷肥的利用率,因此,今后在盐碱地

  11. 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.

  12. 聚合硫酸铁铝在污水处理厂二级出水处理中的应用%Application of polymeric aluminum ferric sulfate to the treatment of secondary effluent in a wastewater treatment plant

    Institute of Scientific and Technical Information of China (English)

    蒋贞贞; 朱俊任


    The secondary effluent of Dadukou Wastewater Treatment Plant in Chongqing has been investigated. The effects of the dosage of self-made polymeric aluminum ferric sulfate (PAFS),and initial pH of water body on the re-moving effectiveness of total phosphorus (TP) and ammonia nitrogen (NH3-N) from the secondary effluent in the wastewater treatment plant are studied. The research results show that when the mass concentration of PAFS is 13 mg/L,the residual TP mass concentration is 0.094 mg/L,the first class A wastewater discharge standard can be reached. Meanwhile NH3-N removing rate reaches 24.8%. Compared with PAFC ,PAC and PFS which are sold in markets,PAFC has higher coagulation effectiveness,and lower dosages. Furthermore,PAFC has stronger charge neutralization and adsorption bridging capacities.%以重庆大渡口污水处理厂的二级出水为考察对象,研究了自制聚合硫酸铝铁(PAFS)投加量、水体初始pH对污水处理厂二级出水的TP、NH3-N去除效果的影响。研究表明:当PAFS投加质量浓度为13 mg/L时,剩余TP质量浓度为0.094 mg/L,达到污水排放一级A标准,同时NH3-N去除率为24.8%。与市售混凝剂PAFC、PAC、PFS相比,PAFS具有较好的混凝效果和较低的投加量,同时PAFS还具有更强的电荷中和和吸附架桥能力。

  13. 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...

  14. Determination of aluminum in aluminum electrolyte by EDTA back titration with ethanol-cuprous chloride-ammonium chloride-hydrochloric acid complex solvent separation%乙醇-氯化亚铜-氯化铵-盐酸复合溶剂分离-EDTA返滴定法测定铝电解质中单质铝

    Institute of Scientific and Technical Information of China (English)

    蒲秋梅; 任凤莲; 曹福悦


    新型低温铝电解质体系物相组成复杂,单质铝的分离测定尤为困难.本文采用高选择性复合溶剂乙醇-氯化亚铜-氯化铵-盐酸(ECAH)直接分离后测定铝电解质中单质铝,成功解决了单质铝与其它铝的化合物分离困难的问题,有效降低了铝电解质溶样时铝的氟化物的微溶效应带来的误差,为铝电解质中单质铝的物相分析提供了可靠的研究方案.采用经典ED-TA络合返滴定法测得铝电解质样品中单质铝含量,加标回收率在97%~103%之间,RSD(n=6)为1.1%和1.5%.测定结果和Al-CAS-OP-CPC四元络合光度法测定结果进行比对,结果一致.%It was particularly difficult to separate and determine aluminum in new low-temperature aluminum electrolyte system because of its complicated components. In this paper, aluminum in aluminum electrolyte was directly separated and determined using high-selectivity ethanol -cuprous chlorideammomum chloride-hydrochloric acid (ECAH) as complex solvent. This method successfully settled the problem of difficult separation of aluminum from aluminum compounds, effectively reduced the determination error introduced by slight soluble effect of fluoride of aluminum during the dissolution of aluminum electrolyte, and provided a reliable research method for the phase analysis of aluminum in aluminum electrolyte. Aluminum in aluminum electrolyte samples was determined by classic EDTA complexing back titration method. The standard addition recoveries were 97%-103 %, and the relative standard deviations (RSD, n=6) were 1. 1 % and 1. 5 %, respectively. The determination results were in good agreement with those obtained by Al-CAS-OP-CPC quaternary complex photometry.

  15. 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

  16. 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.

  17. Effect of Aluminum Sulfate on the F Migration Regularity in Soda Alkali-Saline Soil%硫酸铝对苏打盐碱土中氟迁移规律的影响

    Institute of Scientific and Technical Information of China (English)

    刘金华; 赵兰坡; 王鸿斌; 张忠庆; 张志丹


    The paper researched F migration regularity and the change of pH in soda alkali-saline soil at different ratio of Al3+ and F-by leaching method.The results showed that,pH of eluent was decreased obviously by applying aluminum sulfate to soda alkali-saline soil which showed extremely significant difference compared with the blank control.And a decreasing tendency of pH was found when leaching times and the relative content of Al3+ were increasing.There were great differences in the dynamic migration and total leaching loss rate of F under the action of different ration of Al3+ and F-in the soil.The leaching loss rate of each time changed little for 1∶1 treatment,decreased slightly after an increase for treatments of(1∶2)~(1∶4),decreased obviously for treatments of(1∶5)~(1∶7).Compared to the control,the total leaching loss rate was decreased in soda alkali-saline soil by applying aluminum sulfate.So it could decrease F migration from soil body to groundwater and reduce daily fluoride intake for people and animals by drinking groundwater.But the degreased degree of total F leaching loss rate was relevant to the relative content of Al3+.It was relative higher for 1∶4 treatment and lower for 1∶1 treatment due to the change of pH,quantity of Al oxide and hydroxide,electric charge of soil colloid and aluminum releasing by soil itself.%采用土柱淋洗法,研究不同铝氟摩尔比下苏打盐碱土中氟的迁移过程及pH值变化情况。结果表明,苏打盐碱土施铝后,能够明显降低淋洗液的pH值,与空白相比,差异均达极显著水平。并且随着淋洗次数和铝相对含量的增加,pH值呈现逐渐降低的趋势。不同铝氟摩尔比作用下,氟在碱土中的迁移动态及总淋失率存在较大的差别。随着淋洗次数的增加,1∶1处理的每次淋失率变化较缓,(1∶2)~(1∶4)处理呈先增加后降低的趋势,而(1∶5)~(1∶7)处理明显下降。与对照

  18. [Aluminum induces chromosome aberrations in wheat root meristem cells]. (United States)

    Bulanova, N V; Synzynys, B I; Koz'min, G V


    The yield and pattern of chromosome structure aberrations in wheat seedlings treated with aluminum nitrate and aluminum sulfate at various concentrations have been determined by the anaphase method. Aluminum has a genotoxic effect causing genome, chromatid, and chromosome aberrations in apical root meristem cells. The relationship between the total yield of structural mutations and the aluminum concentration follows a bell-shaped curve. The mutagenic activity of aluminum nitrate peaks at 10(-3) mg/ml, which is twice as high as the permissible concentration limit (PCL) of aluminum in potable water. The maximum of the mutagenic activity of aluminum sulfate is observed at 5 x 10(-4) mg/ml, i.e., one PCL. Tap water boiled for 2 h in an aluminum vessel has virtually no genotoxic effect on wheat cells.

  19. 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.

  20. 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.

  1. 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。

  2. 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.

  3. Sensitive Determination of Chondroitin Sulfate by Fluorescence Recovery of an Anionic Aluminum Phthalocyanine-Cationic Surfactant Ion-Association Complex Used as a Fluorescent Probe Emitting at Red Region%四磺基铝酞菁-十四烷基二甲基乙基氯化铵离子缔合物红色荧光探针用于硫酸软骨素的测定

    Institute of Scientific and Technical Information of China (English)

    陈林; 黄萍; 杨惠卿; 邓雅斌; 郭梦林; 李东辉


    sur‐factants have the ability to quench the fluorescence of tetrasulfonated aluminum phthalocyanine (AlS4 Pc) ,a strongly fluorescent compound which emits at red region ,with high efficiency .But ,the fluorescence of the above‐mentioned fluorescence quenching system recovered significantly when chondroitin sulfate (CS) exits .Tetradecyl dimethyl benzyl ammonium chloride(TDBAC) which was screened from all of the candidates of cationic surfactants was chosen as the quencher because it shows the most effi‐cient quenching effect .It was found that the fluorescence of AlS4 Pc was extremely quenched by TDBAC because of the formation of association complex between AlS4 Pc and TDBAC .Fluorescence of the association complex recovered dramatically after the ad‐dition of chondroitin sulfate (CS) due to the ability of chondroitin sulfate to shift the association equilibrium of the association , leading to the release of AlS4 Pc ,thus resulting in an increase in the fluorescence of the reaction system .Based on this phenome‐non ,a novel method with simplicity ,accuracy and sensitivity was developed for quantitative determination of CS .Factors inclu‐ding the reaction time ,influencing factors and the effect of coexisting substances were investigated and discussed .Under opti‐mum conditions the linear range of the calibration curve was 0 .20~10 .0μg · mL -1 .The detection limit for CS was 0 .070 μg · mL -1 .The method has been applied to the analysis of practical samples with satisfied results .This work expands the applica‐tions of AlS4 Pc in biomedical area .

  4. Adsorption of High Fluoride in Drinking Water by Aluminum Sulfate Impregnated Activated Alumina Granules%硫酸铝浸渍活性氧化铝球吸附饮水中的高浓度氟

    Institute of Scientific and Technical Information of China (English)

    吴代赦; 刘容; 杜俊逸; 李萍


    Aluminum sulfate impregnated activated alumina granules (AIAA) are the common adsorbent for high fluoride (F) drinking water, the adsorption properties of AIAA were influenced by sorts of factors. In batch adsorption experiments, the adsorption performance of AIAA in high fluoride drinking water was investigated by examining the effects of different factors, including AIAA amount to fluoride solution volume (m(AIAA): V) (2 -40 g · L-1) ,fluoride mass concentration (ρ(F)) (2 - 100 mg · L-1) ,pH (4 - 10) ,temperature ( 11 -33 ℃ ) and time on fluoride adsorption. Under the conditions of 11 -33 ℃ ,pH of 4 - 10,m(AIAA) : V at 20 g · L-1 ,AIAA could remove more than 90% F- for fluoride-containing water (10 mg · L-1) after 3 h,which satisfied sufficiently with the hygienic standard for F in drinking water. Langmuir and Freundlich models were adopted to fit the adsorption data. The results showed that the linear Langmuir model was the best fitting method at ρ(F) from 2 to 100 mg · L-1 ,pH from 5 to 10 and temperature from 11 to 33 ℃ ; and the non-linear Freundlich model was the best fitting method at ρ(F) from 2 to 1 000 mg· L-1 or at ρ(F) from 2 to 100 mg ·L -1 ,and pH at 4. With the increasing of ρ(F) in solution and temperature, the decreasing of solution pH, the adsorption capacity of AIAA was increased gradually.%硫酸铝浸渍活性氧化铝球(AIAA)是饮水除氟领域常用的吸附剂,它对氟的吸附性能受各种因素的影响.静态吸附通过改变AIAA质量与氟溶液体积比(m(AIAA):V)(2~40g·L-1)、氟的质量浓度(p(F))(2~100mg·L-1)、pH值(4~10)、温度(11~33℃)和时间等实验参数,研究这些因素对AIAA吸附除氟的影响.在11~33℃的温度范围内、pH值变化为4~10之间时,当m(AIAA):V为20 g·L-1,3 h内处理ρ(F)为10 mg·L-1水溶液其氟的去除率可达90%以上,足以保证其满足饮用水的含氟标准.利用Langmuir和Freundlich模型对吸附数据进行了拟合研

  5. Response of Atmospheric Methane Consumption by Maine Forest Soils to Exogenous Aluminum Salts†



    Atmospheric methane consumption by Maine forest soils was inhibited by additions of environmentally relevant levels of aluminum. Aluminum chloride was more inhibitory than nitrate or sulfate salts, but its effect was comparable to that of a chelated form of aluminum. Inhibition could be explained in part by the lower soil pH values which resulted from aluminum addition. However, significantly greater inhibition by aluminum than by mineral acids at equivalent soil pH values indicated that inhi...

  6. 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).

  7. Pharmacokinetic study on compound aluminum sulfate injection after i.v. and in situ administration in rabbits%复方硫酸铝注射液新西兰兔静脉注射和局部注射药代动力学研究

    Institute of Scientific and Technical Information of China (English)

    徐风华; 陈宜鸿; 方翼; 高秀云


    目的:研究复方硫酸铝注射液静脉注射后的药代动力学以及肌肉和皮下注射后的全身吸收.方法:兔耳静脉、股四头肌和背部皮下注射,耳静脉采血,采用等离子体质谱法测定血铝浓度,DAS药代动力学程序处理血药浓度数据.结果:静脉注射复方硫酸铝注射液1 mg·kg-1 (剂量均以无水硫酸铝计),硫酸铝体内药代动力学过程符合二房室模型,t1/2β为 1.08±0.46 h,AUC0-12h为 1.52±0.92 mg·h·L-1(n=5).股四头肌注射复方硫酸铝注射液80 mg·kg-1,血铝浓度略有升高,但不明显,采用梯形法计算曲线下面积,平均AUC0-24h为 2.93±1.82 mg·h·L-1(n=5),相对生物利用度约为 2.41%.皮下注射160 mg·kg-1,血铝浓度没有明显的峰值,平均AUC0-24h为 0.88±1.14 mg·h·L-1(n=5),相对生物利用度约为 0.36%.结论:复方硫酸铝注射液静脉注射后血液中清除速率快,局部注射后全身吸收量很低,是一种安全的新制剂.%AIM: To study the pharmacokinetics of compound aluminum sulfate injection after i.v. administration and aluminum absorption after i.m. and s.c. administration in New Zealand rabbits. METHODS: Compound aluminum sulfate injection was administrated i.v. to the left-ear at the dose of 1 mg·kg-1, i.m. in quadriceps at the dose of 80 mg·kg-1 or s.c. under back skin at the dose of 160 mg·kg-1 (anhydrous aluminum sulfate/body weight). Blood samples were collected at different time after injection from the right-ear vein. ICP-MS assay was used to determine the aluminum (Al) concentration. Pharmacokinetic parameters were calculated with DAS program. RESULTS: The blood Al concentration-time profiles after i.v. injection fitted to a two-compartment model, with t1/2β 1.08±0.46 h and AUC0-12h 1.52±0.92 mg·h·L-1 (n=5). There was no obvious increase in Al concentration after i.m. injection of 80 mg·kg-1 or s.c. injection of 160 mg·kg-1 aluminum sulfate. The average AUC0-24h of i.m. injection was 2.93±1.82 mg·h·L-1

  8. 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)

  9. 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

  10. 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.

  11. 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.

  12. Aluminum alloy (United States)

    Blackburn, Linda B. (Inventor); Starke, Edgar A., Jr. (Inventor)


    This invention relates to aluminum alloys, particularly to aluminum-copper-lithium alloys containing at least about 0.1 percent by weight of indium as an essential component, which are suitable for applications in aircraft and aerospace vehicles. At least about 0.1 percent by weight of indium is added as an essential component to an alloy which precipitates a T1 phase (Al2CuLi). This addition enhances the nucleation of the precipitate T1 phase, producing a microstructure which provides excellent strength as indicated by Rockwell hardness values and confirmed by standard tensile tests.

  13. 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.

  14. Role of iron and aluminum coagulant metal residuals and lead release from drinking water pipe materials. (United States)

    Knowles, Alisha D; Nguyen, Caroline K; Edwards, Marc A; Stoddart, Amina; McIlwain, Brad; Gagnon, Graham A


    Bench-scale experiments investigated the role of iron and aluminum residuals in lead release in a low alkalinity and high (> 0.5) chloride-to-sulfate mass ratio (CSMR) in water. Lead leaching was examined for two lead-bearing plumbing materials, including harvested lead pipe and new lead: tin solder, after exposure to water with simulated aluminum sulfate, polyaluminum chloride and ferric sulfate coagulation treatments with 1-25-μM levels of iron or aluminum residuals in the water. The release of lead from systems with harvested lead pipe was highly correlated with levels of residual aluminum or iron present in samples (R(2) = 0.66-0.88), consistent with sorption of lead onto the aluminum and iron hydroxides during stagnation. The results indicate that aluminum and iron coagulant residuals, at levels complying with recommended guidelines, can sometimes play a significant role in lead mobilization from premise plumbing.

  15. 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

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. Chronic aluminum intake causes Alzheimer's disease: applying Sir Austin Bradford Hill's causality criteria. (United States)

    Walton, J R


    Industrialized societies produce many convenience foods with aluminum additives that enhance various food properties and use alum (aluminum sulfate or aluminum potassium sulfate) in water treatment to enable delivery of large volumes of drinking water to millions of urban consumers. The present causality analysis evaluates the extent to which the routine, life-long intake, and metabolism of aluminum compounds can account for Alzheimer's disease (AD), using Austin Bradford Hill's nine epidemiological and experimental causality criteria, including strength of the relationship, consistency, specificity, temporality, dose-dependent response, biological rationale, coherence with existing knowledge, experimental evidence, and analogy. Mechanisms that underlie the risk of low concentrations of aluminum relate to (1) aluminum's absorption rates, allowing the impression that aluminum is safe to ingest and as an additive in food and drinking water treatment, (2) aluminum's slow progressive uptake into the brain over a long prodromal phase, and (3) aluminum's similarity to iron, in terms of ionic size, allows aluminum to use iron-evolved mechanisms to enter the highly-active, iron-dependent cells responsible for memory processing. Aluminum particularly accumulates in these iron-dependent cells to toxic levels, dysregulating iron homeostasis and causing microtubule depletion, eventually producing changes that result in disconnection of neuronal afferents and efferents, loss of function and regional atrophy consistent with MRI findings in AD brains. AD is a human form of chronic aluminum neurotoxicity. The causality analysis demonstrates that chronic aluminum intake causes AD.

  2. 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)


    Directory of Open Access Journals (Sweden)

    A. E. Baranchikov


    Full Text Available Subject of Study. The paper presents results of characterization for neodymium doped yttrium aluminum garnet nanopowders - YAG:Nd3+ by the method of scanning electronic microscopy. Method. Synthesis of YAG:Nd3+ was carried out by sol-gel method from nitrate or acetate - nitrate solutions with addition of some organic compounds and ammonia as well. Such substances were used as the source ones: oxides of neodymium and yttrium with the content of the basic substance equal to 99.999 %; organic compounds: citric acid with the content of the basic substance not less than 99.0 %; ethylene glycol (99.5%; the ammonium lauryl sulfate (99.0 %; urea (99.0 % of Alfa Aesar, Fluka, Aldrich companies. Oxides of yttrium and neodymium (5 at. % were dissolved in 50% acetic acid, nitrate aluminum was added with a view to the resulting product Y2,85Nd0,15Al5,0O12, the solution was stirred and heated to 60С before reaching its transparency and uniformity. The weight of the portion corresponding to the stoichiometry YAG was 2.0 g. 50 % aqueous solutions of organic substances or 5% NH4OH in a weight ratio of 1:1 to the weight of the garnet were added in aqueous solutions, placed into glass cups. The solutions were thoroughly mixed first using a conventional stirrer, then on ultrasonic installation with simultaneous 60 С heating for 2 hours. Drying of solutions to the consistency of a powder or a thick gel was carried out at 110 С. Then the samples were placed into platinum cups and annealed in a tube furnace at 950 - 1050 С for the period from 0.5 to 2 hours. Additional annealing of the powders in the air at 950 - 1060С were carried out for the purpose of powders clarifying for residual amorphous carbon removal. Main Results. The synthesized powder precursors and powders after annealing were examined using a polarizing microscope to identify anisotropic crystalline phases. X-ray analysis of the synthesized samples was carried out on a DRON - 4 and UDR - 63

  4. Effects of Ca(OH)2 assisted aluminum sulfate coagulation on the removal of humic acid and the formation potentials of tri-halomethanes and haloacetic acids in chlorination

    Institute of Scientific and Technical Information of China (English)

    Jinming Duan; Xiaoting Cao; Cheng Chen; Dongrui Shi; Genmao Li; Dennis Mulcahy


    The effects of addition of calcium hydroxide on aluminum sulphate (or alum) coagulation for removal of natural organic matter (NOM) and its subsequent effect on the formation potentials of two major types of regulated disinfection byproducts (DBPs),haloacetic acids (HAAs) and trihalomethanes (THMs),have been examined.The results revealed several noteworthy phenomena.At the optimal coagulation pH (i.e.6),the coagulation behavior of NOM water solutions versus alum dose,showed large variation and a consequent great change in the formation potentials of the DBPs at certain coagulant doses.However,with addition of a relatively small amount of Ca(OH)2,although the zeta potential of coagulated flocs remained almost the same,NOM removal became more consistent with alum dose.Importantly,also the detrimental effect of charge reversal on NOM removal at the low coagulant dose disappeared.This resulted in a steady decrease in the formation potentials of DBPs as a function of the coagulant dose.Moreover,the addition of Ca(OH)2 broadened the pH range of alum coagulation and promoted further reduction of the formation potentials of the DBPs.The enhancement effects of Ca(OH)2 assisted alum coagulation are especially pronounced at pH 7 and 8.Finally,synchronous fluorescence spectra showed that the reduction in DBPs formation potential by Ca(OH)2-assisted alum coagulation was connected to an enhanced removal of small hydrophobic and hydrophilic HA molecules.Ca(OH)2-assistance of alum coagulation appeared to increase substantially the removal of the hydrophilic HA fraction responsible for HAAs formation,prompting further reduction of HAA formation potentials.

  5. 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.

  6. 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.

  7. 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.

  8. 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....

  9. 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...

  10. Estudio Comparativo de Sulfato de Aluminio y Semillas de Moringa oleifera para la Depuración de Aguas con Baja Turbiedad Comparative Study of Aluminum Sulfate and Moringa oleifera seeds as Coagulants in the Clarification of Water with Low Turbidity

    Directory of Open Access Journals (Sweden)

    Patrícia G.S Lédo


    Full Text Available El presente trabajo tiene como objetivo investigar la eficiencia de dos coagulantes, el sulfato de aluminio y semillas de Moringa oleifera, para remoción de turbiedad en muestras del agua provenientes de la Laguna de Jiqui, estado del Rio Grande do Norte, Natal-Brasil. Las dosificaciones y pH de los coagulantes fueron variados entre límites establecidos. Se realizaron pruebas, en tubos de ensayo Jar-Test y medidas de movilidad electroforética para determinar el potencial Zeta y para determinar los posibles mecanismos involucrados en el proceso de coagulación. Los mecanismos de coagulación con semillas de Moringa oleifera son adsorción y neutralización de cargas y adsorción y formación de puentes. Los resultados sugieren que para aguas de baja turbiedad, las semillas de Moringa oleifera pueden ser un sustituto potencialmente viable al sulfato de aluminio para la clarificación de dichas aguas.The objective of the present work is to investigate the efficiency of a coagulant prepared from Moringa oleifera seeds, for clarifying water samples with low turbidity from the Jiqui Lake, in the State of Rio Grande do Norte, Natal-Brazil. The dosages and pH of the coagulants were changed within defined limits. Jar-test essays and measurements of electrophoretic mobility were done to determine the Zeta potential and the possible mechanisms involved in the coagulation process. The mechanisms of coagulation with Moringa oleifera are absorption and neutralization of charges and absorption and bridging. The results suggest that for low turbidity waters, Moringa oleifera seeds represent a potentially viable substitute of aluminum sulfate for water clarification.

  11. 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.

  12. 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.

  13. 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.


    Directory of Open Access Journals (Sweden)



    Full Text Available In municipal solid waste, aluminum is the main nonferrous metal, approximately 80- 85% of the total nonferrous metals. The income per ton gained from aluminum recuperation is 20 times higher than from glass, steel boxes or paper recuperation. The object of this paper is the design of a 300 kN press for aluminum box bundling.

  15. 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)...

  16. 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...

  17. 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...

  18. 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...

  19. 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...

  20. Is Encephalopathy a Mechanism to Renew Sulfate in Autism?

    Directory of Open Access Journals (Sweden)

    Laurie Lentz-Marino


    Full Text Available This paper makes two claims: (1 autism can be characterized as a chronic low-grade encephalopathy, associated with excess exposure to nitric oxide, ammonia and glutamate in the central nervous system, which leads to hippocampal pathologies and resulting cognitive impairment, and (2, encephalitis is provoked by a systemic deficiency in sulfate, but associated seizures and fever support sulfate restoration. We argue that impaired synthesis of cholesterol sulfate in the skin and red blood cells, catalyzed by sunlight and nitric oxide synthase enzymes, creates a state of colloidal instability in the blood manifested as a low zeta potential and increased interfacial stress. Encephalitis, while life-threatening, can result in partial renewal of sulfate supply, promoting neuronal survival. Research is cited showing how taurine may not only help protect neurons from hypochlorite exposure, but also provide a source for sulfate renewal. Several environmental factors can synergistically promote the encephalopathy of autism, including the herbicide, glyphosate, aluminum, mercury, lead, nutritional deficiencies in thiamine and zinc, and yeast overgrowth due to excess dietary sugar. Given these facts, dietary and lifestyle changes, including increased sulfur ingestion, organic whole foods, increased sun exposure, and avoidance of toxins such as aluminum, mercury, and lead, may help to alleviate symptoms or, in some instances, to prevent autism altogether.

  1. 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

  2. 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.

  3. Conditioned aversion of aluminum sulfate in black ducks (United States)

    Sparling, D.W.


    Three experiments were conducted to determine if reduced consumption of foods with elevated Al levels by black ducks (Anas rubripes) was due to taste aversion, conditioned taste aversion or malaise. Black ducks preferred a diet with 1,000 ppm Al over a control diet but ate less of a diet with 5,000 ppm Al. Prior experience with the high Al diet enhanced preference for the control diet. Changes in body weight and food consumption through time suggested that aversion to the high Al diet was a conditioned response to mild malaise.

  4. 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.

  5. 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.

  6. Electrochemical Coupling between Active Particulates and Aluminum Alloys (United States)


    Sodium Vanadate (M) Sodium Stannate (M) Catechol (M) Pyrrole (M) Ammonium Persulfate (M) Phosphate Composite 3.00 3.62 0.00 0.00 0.00 0.1 0.2...Days Immersion in DHS Phosphate Vanadate Molybdate Sulfate 16 Summary  The polypyrrole (PPy) Al flake composite (PAFC...Novel Routes to Synthesis of Nano-Particulates of Polypyrrole 18 Thank You. 19

  7. Aspects of aluminum toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Hewitt, C.D.; Savory, J.; Wills, M.R. (Univ. of Virginia Health Sciences Center, Charlottesville (USA))


    Aluminum is the most abundant metal in the earth's crust. The widespread occurrence of aluminum, both in the environment and in foodstuffs, makes it virtually impossible for man to avoid exposure to this metal ion. Attention was first drawn to the potential role of aluminum as a toxic metal over 50 years ago, but was dismissed as a toxic agent as recently as 15 years ago. The accumulation of aluminum, in some patients with chronic renal failure, is associated with the development of toxic phenomena; dialysis encephalopathy, osteomalacic dialysis osteodystrophy, and an anemia. Aluminum accumulation also occurs in patients who are not on dialysis, predominantly infants and children with immature or impaired renal function. Aluminum has also been implicated as a toxic agent in the etiology of Alzheimer's disease, Guamiam amyotrophic lateral sclerosis, and parkinsonism-dementia. 119 references.

  8. Aluminum powder metallurgy processing

    Energy Technology Data Exchange (ETDEWEB)

    Flumerfelt, J.F.


    The objective of this dissertation is to explore the hypothesis that there is a strong linkage between gas atomization processing conditions, as-atomized aluminum powder characteristics, and the consolidation methodology required to make components from aluminum powder. The hypothesis was tested with pure aluminum powders produced by commercial air atomization, commercial inert gas atomization, and gas atomization reaction synthesis (GARS). A comparison of the GARS aluminum powders with the commercial aluminum powders showed the former to exhibit superior powder characteristics. The powders were compared in terms of size and shape, bulk chemistry, surface oxide chemistry and structure, and oxide film thickness. Minimum explosive concentration measurements assessed the dependence of explosibility hazard on surface area, oxide film thickness, and gas atomization processing conditions. The GARS aluminum powders were exposed to different relative humidity levels, demonstrating the effect of atmospheric conditions on post-atomization processing conditions. The GARS aluminum powders were exposed to different relative humidity levels, demonstrating the effect of atmospheric conditions on post-atomization oxidation of aluminum powder. An Al-Ti-Y GARS alloy exposed in ambient air at different temperatures revealed the effect of reactive alloy elements on post-atomization powder oxidation. The pure aluminum powders were consolidated by two different routes, a conventional consolidation process for fabricating aerospace components with aluminum powder and a proposed alternative. The consolidation procedures were compared by evaluating the consolidated microstructures and the corresponding mechanical properties. A low temperature solid state sintering experiment demonstrated that tap densified GARS aluminum powders can form sintering necks between contacting powder particles, unlike the total resistance to sintering of commercial air atomization aluminum powder.


    Institute of Scientific and Technical Information of China (English)

    梁伟; 叶红齐; 陈玉琼; 刘秀云


    以丙烯酸丁酯、苯乙烯为单体,十二烷基硫酸钠为乳化剂,过硫酸铵为引发剂,通过乳液共聚包覆在片状铝粉的表面,并探讨单体配比、反应温度、反应时间对包覆铝粉耐酸腐蚀性能的影响.结果表明,在单体丙烯酸丁酯与苯乙烯的配比mBA/mSt为1∶1、反应温度为80℃、反应时间为4 h时,包覆铝粉的耐酸腐蚀性能较好.运用红外光谱和扫描电镜对包覆样品进行分析表征.%To improve the corrosion resistance of the flaky aluminum powder, the flaky aluminum powder was coated by emulsion polymerization, which used butyl acrylate and styrene as monomers, sodium dodecyl sulfate as emulsifier and ammonium persulfate as initiator. The effect of the proportion of butyl acrylate and styrene, reaction temperature and reaction time on the corrosion resistance of the coated aluminum powder was examined. The results show: its acid resistance is improved obviously; the coated aluminum powder obtained under the conditions that the proportion of butyl acrylate and styrene (mBA/mSt) is 1:1, reaction temperature is 80 ℃ and reaction time is 4 h has good acid resistance. Moreover, the encapsulated samples were analyzed and characterized by Fourier transform infrared spectroscope and scanning electron microscope.

  10. Alternative process to produce UF{sub 4} using the effluent from ammonium uranyl carbonate route

    Energy Technology Data Exchange (ETDEWEB)

    Silva Neto, Joao B.; Garcia, Rafael Henrique Lazzari; Dal Vechio, Edvaldo, E-mail: [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), SP (Brazil); Riella, Humberto G., E-mail: [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil); Instituto Nacional de Ciencias e Tecnologia de Reatores Nucleares Inovadores (INCT/CNPq) (Brazil); Carvalho, Elita F. Urano de; Durazzo, Michelangelo [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), SP (Brazil); Instituto Nacional de Ciencias e Tecnologia de Reatores Nucleares Inovadores (INCT/CNPq) (Brazil)


    The Nuclear Fuel Centre of IPEN / CNEN - SP develops and manufactures dispersion fuel with high uranium concentration. It meets the demand of the IEA-R1 reactor and future research reactors to be constructed in Brazil. The fuel uses uranium silicide (U{sub 3}Si{sub 2}) dispersed in aluminum. For producing the fuel, the process of uranium hexafluoride (UF{sub 6}) conversion consist in obtaining U{sub 3}Si{sub 2} and / or U{sub 3}O{sub 8} through the preparation of intermediate compounds, among them ammonium uranyl carbonate - AUC, ammonium diuranate - DUA and uranium tetrafluoride - UF{sub 4}. This work describes a procedure for preparing uranium tetrafluoride via a dry route, using as raw material the filtrate generated when ammonium uranyl carbonate is routinely produced. The filtrate consists mainly of a solution containing high concentrations of ammonium (NH{sup 4+}), fluoride (F{sup -}), carbonate (CO{sup 3-}) and low concentrations of uranium. The procedure consists in recovering NH{sup 4F} and uranium, as UF{sub 4}, through the crystallization of ammonium bifluoride (NH{sub 4}HF{sub 2}) and, in a later step, the addition of UO{sub 2}, occurring fluoridation and decomposition. The UF{sub 4} obtained is further diluted in the UF{sub 4} produced routinely at IPEN / CNEN-SP by a wet route process. (author)

  11. 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.

  12. 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.

  13. Is the Aluminum Hypothesis Dead?


    Lidsky, Theodore I.


    The Aluminum Hypothesis, the idea that aluminum exposure is involved in the etiology of Alzheimer disease, dates back to a 1965 demonstration that aluminum causes neurofibrillary tangles in the brains of rabbits. Initially the focus of intensive research, the Aluminum Hypothesis has gradually been abandoned by most researchers. Yet, despite this current indifference, the Aluminum Hypothesis continues to attract the attention of a small group of scientists and aluminum continues to be viewed w...

  14. High energy density aluminum battery

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Gilbert M.; Paranthaman, Mariappan Parans; Dai, Sheng; Dudney, Nancy J.; Manthiram, Arumugan; McIntyre, Timothy J.; Sun, Xiao-Guang; Liu, Hansan


    Compositions and methods of making are provided for a high energy density aluminum battery. The battery comprises an anode comprising aluminum metal. The battery further comprises a cathode comprising a material capable of intercalating aluminum or lithium ions during a discharge cycle and deintercalating the aluminum or lithium ions during a charge cycle. The battery further comprises an electrolyte capable of supporting reversible deposition and stripping of aluminum at the anode, and reversible intercalation and deintercalation of aluminum or lithium at the cathode.

  15. Minimizing residual aluminum concentration in treated water by tailoring properties of polyaluminum coagulants. (United States)

    Kimura, Masaoki; Matsui, Yoshihiko; Kondo, Kenta; Ishikawa, Tairyo B; Matsushita, Taku; Shirasaki, Nobutaka


    Aluminum coagulants are widely used in water treatment plants to remove turbidity and dissolved substances. However, because high aluminum concentrations in treated water are associated with increased turbidity and because aluminum exerts undeniable human health effects, its concentration should be controlled in water treatment plants, especially in plants that use aluminum coagulants. In this study, the effect of polyaluminum chloride (PACl) coagulant characteristics on dissolved residual aluminum concentrations after coagulation and filtration was investigated. The dissolved residual aluminum concentrations at a given coagulation pH differed among the PACls tested. Very-high-basicity PACl yielded low dissolved residual aluminum concentrations and higher natural organic matter (NOM) removal. The low residual aluminum concentrations were related to the low content of monomeric aluminum (Ala) in the PACl. Polymeric (Alb)/colloidal (Alc) ratio in PACl did not greatly influence residual aluminum concentration. The presence of sulfate in PACl contributed to lower residual aluminum concentration only when coagulation was performed at around pH 6.5 or lower. At a wide pH range (6.5-8.5), residual aluminum concentrations residual aluminum concentrations did not increase with increasing the dosage of high-basicity PACl, but did increase with increasing the dosage of normal-basicity PACl. We inferred that increasing the basicity of PACl afforded lower dissolved residual aluminum concentrations partly because the high-basicity PACls could have a small percentage of Ala, which tends to form soluble aluminum-NOM complexes with molecular weights of 100 kDa-0.45 μm.

  16. Is the Aluminum Hypothesis dead? (United States)

    Lidsky, Theodore I


    The Aluminum Hypothesis, the idea that aluminum exposure is involved in the etiology of Alzheimer disease, dates back to a 1965 demonstration that aluminum causes neurofibrillary tangles in the brains of rabbits. Initially the focus of intensive research, the Aluminum Hypothesis has gradually been abandoned by most researchers. Yet, despite this current indifference, the Aluminum Hypothesis continues to attract the attention of a small group of scientists and aluminum continues to be viewed with concern by some of the public. This review article discusses reasons that mainstream science has largely abandoned the Aluminum Hypothesis and explores a possible reason for some in the general public continuing to view aluminum with mistrust.

  17. Anodizing Aluminum with Frills. (United States)

    Doeltz, Anne E.; And Others


    "Anodizing Aluminum" (previously reported in this journal) describes a vivid/relevant laboratory experience for general chemistry students explaining the anodizing of aluminum in sulfuric acid and constrasting it to electroplating. Additions to this procedure and the experiment in which they are used are discussed. Reactions involved are…

  18. 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...

  19. 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...

  20. The aluminum smelting process. (United States)

    Kvande, Halvor


    This introduction to the industrial primary aluminum production process presents a short description of the electrolytic reduction technology, the history of aluminum, and the importance of this metal and its production process to modern society. Aluminum's special qualities have enabled advances in technologies coupled with energy and cost savings. Aircraft capabilities have been greatly enhanced, and increases in size and capacity are made possible by advances in aluminum technology. The metal's flexibility for shaping and extruding has led to architectural advances in energy-saving building construction. The high strength-to-weight ratio has meant a substantial reduction in energy consumption for trucks and other vehicles. The aluminum industry is therefore a pivotal one for ecological sustainability and strategic for technological development.

  1. 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+}.

  2. Effect of impurities in industrial salts on aluminum scrap melting

    Energy Technology Data Exchange (ETDEWEB)

    Ye, J.; Sahai, Y. [Ohio State Univ., Columbus, OH (United States). Dept. of Materials Science and Engineering; Revet, A. [Kalium Canada, ltd., Regina, Saskatchewan (Canada)


    Aluminum scrap such as Used Beverage Containers (UBC) is melted under a protective molten salt cover. An appropriate salt protects metal from oxidation, promotes coalescence of molten droplets, and separates clean metal from the oxide contamination. Generally, the salt compositions for aluminum scrap recycling are based on equimolar mixtures of NaCl and KCl. A small amount of fluoride is also added in the salt. In the past, laboratory research at universities and industrial laboratories have been limited to pure salts. However, the industrial salts have impurities such as sulfates and other insoluble materials. These impurities have a pronounced effect on the efficiency of the scrap remelting process. In this paper, the role of impurities in industrial salts in terms of their chemical interactions with the metal are summarized. The efficiency of different industrial grade salts containing varying amounts of sulfates and other insoluble impurities for scrap recycling is compared.

  3. 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.

  4. 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.

  5. 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...

  6. 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

  7. 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...

  8. Clinical biochemistry of aluminum

    Energy Technology Data Exchange (ETDEWEB)

    King, S.W.; Savory, J.; Wills, M.R.


    Aluminum toxicity has been implicated in the pathogenesis of a number of clinical disorders in patients with chronic renal failure on long-term intermittent hemodialysis treatment. The predominant disorders have been those involving either bone (osteomalacic dialysis osteodystrophy) or brain (dialysis encephalopathy). In nonuremic patients, an increased brain aluminum concentration has been implicated as a neurotoxic agent in the pathogenesis of Alzheimer's disease and was associated with experimental neurofibrillary degeneration in animals. The brain aluminum concentrations of patients dying with the syndrome of dialysis encephalopathy (dialysis dementia) are significantly higher than in dialyzed patients without the syndrome and in nondialyzed patients. Two potential sources for the increased tissue content of aluminum in patients on hemodialysis have been proposed: (1) intestinal absorption from aluminum containing phosphate-binding gels, and (2) transfer across the dialysis membrane from aluminum in the water used to prepare the dialysate. These findings, coupled with our everyday exposure to the ubiquitous occurrence of aluminum in nature, have created concerns over the potential toxicity of this metal.

  9. Advances in aluminum pretreatment

    Energy Technology Data Exchange (ETDEWEB)

    Sudour, Michel; Maintier, Philippe [PPG Industries France, 3 Z.A.E. Les Dix Muids, B.P. 89, F-59583 Marly (France); Simpson, Mark [PPG Industries Inc., 1200 Piedmont Troy, Michigan 48083 (United States); Quaglia, Paolo [PPG Industries Italia, Via Garavelli 21, I-15028 Quattordio (Italy)


    As automotive manufacturers continue to look for ways to reduce vehicle weight, aluminum is finding more utility as a body panel component. The substitution of cold-rolled steel and zinc-coated substrates with aluminum has led to new challenges in vehicle pretreatment. As a result, changes to traditional pretreatment chemistries and operating practices are necessary in order to produce an acceptable coating on aluminum body panels. These changes result in increased sludging and other undesirable characteristics. In addition to the chemistry changes, there are also process-related problems to consider. Many existing automotive pretreatment lines simply were not designed to handle aluminum and its increased demands on filtration and circulation equipment. To retrofit such a system is capital intensive and in addition to requiring a significant amount of downtime, may not be totally effective. Thus, the complexities of pre-treating aluminum body panels have actually had a negative effect on efforts to introduce more aluminum into new vehicle design programs. Recent research into ways of reducing the negative effects has led to a new understanding of the nature of zinc phosphate bath -aluminum interactions. Many of the issues associated with the pretreatment of aluminum have been identified and can be mitigated with only minor changes to the zinc phosphate bath chemistry. The use of low levels of soluble Fe ions, together with free fluoride, has been shown to dramatically improve the efficiency of a zinc phosphate system processing aluminum. Appearance of zinc phosphate coatings, coating weights and sludge are all benefited by this chemistry change. (authors)

  10. 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.

  11. 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.

  12. Corrosion Inhibitors for Aluminum. (United States)

    Muller, Bodo


    Describes a simple and reliable test method used to investigate the corrosion-inhibiting effects of various chelating agents on aluminum pigments in aqueous alkaline media. The experiments that are presented require no complicated or expensive electronic equipment. (DDR)

  13. Advances in aluminum anodizing (United States)

    Dale, K. H.


    White anodize is applied to aluminum alloy surfaces by specific surface preparation, anodizing, pigmentation, and sealing techniques. The development techniques resulted in alloys, which are used in space vehicles, with good reflectance values and excellent corrosive resistance.


    Dalrymple, R.S.; Nelson, W.B.


    Treatment of aluminum-base metal surfaces in an autoclave with an aqueous chromic acid solution of 0.5 to 3% by weight and of pH below 2 for 20 to 50 hrs at 160 to 180 deg C produces an extremely corrosion-resistant aluminum oxidechromium film on the surface. A chromic acid concentration of 1 to 2% and a pH of about 1 are preferred. (D.C.W.)

  15. Shuttle Redesigned Solid Rocket Motor aluminum oxide investigations (United States)

    Blomshield, Fred S.; Kraeutle, Karl J.; Stalnaker, Richard A.


    During the launch of STS-54, a 15 psi pressure blip was observed in the ballistic pressure trace of one of the two Space Shuttle Redesigned Solid Rocket Motors (RSRM). One possible scenario for the observed pressure increase deals with aluminum oxide slag formation in the RSRM. The purpose of this investigation was to examine changes which may have occurred in the aluminum oxide formation in shuttle solid propellant due to changes in the ammonium perchlorate. Aluminum oxide formation from three propellants, all having the same formulation, but containing ammonium perchlorate from different manufacturers, will be compared. Three methods have been used to look for possible differences among the propellants. The first method was to examine window bomb movies of the propellants burning at 100, 300 and 600 psia. The motor operating pressure during the pressure blip was around 600 psia. The second method used small samples of propellant which were fired in a combustion bomb which quenched the burning aluminum particles soon after they left the propellant surface. The bomb was fired in both argon and Nitrogen atmospheres at various pressures. Products from this device were examined by optical microscopy. The third method used larger propellant samples fired into a particle collection device which allowed the aluminum to react and combust more completely. This device was pressurized with Nitrogen to motor operating pressures. The collected products were subdivided into size fractions by screening and sedimentation and analyzed optically with an optical microscope. the results from all three methods indicate very small changes in the size distribution of combustion products.

  16. 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...

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 40 CFR 117.3 - Determination of reportable quantities. (United States)


    ... chloride C 1,000 (454) Aluminum sulfate D 5,000 (2,270) Ammonia B 100 (45.4) Ammonium acetate D 5,000 (2... (2,270) Ammonium carbonate D 5,000 (2,270) Ammonium chloride D 5,000 (2,270) Ammonium chromate A 10...) Ferric sulfate C 1,000 (454) Ferrous ammonium sulfate C 1,000 (454) Ferrous chloride B 100 (45.4)...

  3. Aluminum, parathyroid hormone, and osteomalacia

    Energy Technology Data Exchange (ETDEWEB)

    Burnatowska-Hledin, M.A.; Kaiser, L.; Mayor, G.H.


    Aluminum exposure in man is unavoidable. The occurrence of dialysis dementia, vitamin D-resistant osteomalacia, and hypochromic microcytic anemia in dialysis patients underscores the potential for aluminum toxicity. Although exposure via dialysate and hyperalimentation leads to significant tissue aluminum accumulation, the ubiquitous occurrence of aluminum and the severe pathology associated with large aluminum burdens suggest that smaller exposures via the gastrointestinal tract and lungs could represent an important, though largely unrecognized, public health problem. It is clear that some aluminum absorption occurs with the ingestion of small amounts of aluminum in the diet and medicines, and even greater aluminum absorption is seen in individuals consuming large amounts of aluminum present in antacids. Aluminum absorption is enhanced in the presence of elevated circulating parathyroid hormone. In addition, elevated PTH leads to the preferential deposition of aluminum in brain and bone. Consequently, PTH is likely to be involved in the pathogenesis of toxicities in those organs. PTH excess also seems to lead to the deposition of aluminum in the parathyroid gland. The in vitro demonstration that aluminum inhibits parathyroid hormone release is consistent with the findings of a euparathyroid state in dialysis patients with aluminum related vitamin D-resistant osteomalacia. Nevertheless, it seems likely that hyperparathyroidism is at least initially involved in the pathogenesis of aluminum neurotoxicity and osteomalacia; the increases in tissue aluminum stores are followed by suppression of parathyroid hormone release, which is required for the evolution of osteomalacia. Impaired renal function is not a prerequisite for increased tissue aluminum burdens, nor for aluminum-related organ toxicity. Consequently, it is likely that these diseases will be observed in populations other than those with chronic renal disease.

  4. Flotation of kaolinite and diaspore with hexadecyl dimethyl benzyl ammonium chloride

    Institute of Scientific and Technical Information of China (English)

    HU Yue-hua; OUYANG Kui; CAO Xue-feng; ZHANG Li-min


    Tertiary amine was synthesized from fatty amine and formaldehyde. And then the synthesized tertiary amine was used toreact with benzyl chloride to synthesize hexadecyl dimethyl benzyl ammonium chloride (1627) at ambient pressure. Using thesynthesized 1627 as collector, the flotation properties of diaspore and kaolinite were investigated by single mineral and mixedmineral test. The flotation mechanism of diaspore, kaolinite and 1627 was discussed based on FTIR spectra. The results show that themass ratio of aluminum to silicate achieves 15.02 and the recovery of alumina in concentrate is 43.07% using 1627 as a collector. The 1627 is found to be a more effective and a promising collector for reverse flotation to remove aluminum-silicate minerals frombauxite.

  5. Extração simultânea de alumínio, cálcio, magnésio, potássio e sódio do solo com solução de cloreto de amônio Simultaneous extraction of aluminum, calcium, magnesium, potassium, and sodium with ammonium chloride solution

    Directory of Open Access Journals (Sweden)

    R. C. Boeira


    samples used were from Northeastern Brazil fruit growing region and from the Embrapa Environment Experimental Station, located in Jaguariúna County, São Paulo State. The employed methods were: (a simultaneous extraction of the five cations with a 1 mol L-1 NH4Cl; (b extraction of Ca, Mg, and Al with 1 mol L-1 KCl; and (c extraction of K and Na with the Mehlich-1 solution. The NH4Cl solution has a higher Mg extraction capacity than KCl, but they present similar Ca and Al extraction ability. The NH4Cl solution extracted more K and Na than the Mehlich-1 solution. It is concluded that the ammonium chloride solution is a convenient alternative for the extraction of exchangeable Al, Ca, Mg, K, and Na from soils.

  6. Fabrication of aluminum foam from aluminum scrap Hamza

    Directory of Open Access Journals (Sweden)

    O. A. Osman1 ,


    Full Text Available In this study the optimum parameters affecting the preparation of aluminum foam from recycled aluminum were studied, these parameters are: temperature, CaCO3 to aluminum scrap wt. ratio as foaming agent, Al2O3 to aluminum scrap wt. ratio as thickening agent, and stirring time. The results show that, the optimum parameters are the temperature ranged from 800 to 850oC, CaCO3 to aluminum scrap wt. ratio was 5%, Al2O3 to aluminum scrap wt. ratio was 3% and stirring time was 45 second with stirring speed 1200 rpm. The produced foam apparent densities ranged from 0.40-0.60 g/cm3. The microstructure of aluminum foam was examined by using SEM, EDX and XRD, the results show that, the aluminum pores were uniformly distributed along the all matrices and the cell walls covered by thin oxide film.

  7. 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.

  8. 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.

  9. 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...

  10. Microstructural Origins of Cement Paste Degradation by External Sulfate Attack (United States)

    Feng, Pan; Garboczi, Edward J.; Miao, Changwen; Bullard, Jeffrey W.


    A microstructure model has been applied to simulate near-surface degradation of portland cement paste in contact with a sodium sulfate solution. This new model uses thermodynamic equilibrium calculations to guide both compositional and microstructure changes. It predicts localized deformation and the onset of damage by coupling the confined growth of new solids with linear thermoelastic finite element calculations of stress and strain fields. Constrained ettringite growth happens primarily at the expense of calcium monosulfoaluminate, carboaluminate and aluminum-rich hydrotalcite, if any, respectively. Expansion and damage can be mitigated chemically by increasing carbonate and magnesium concentrations or microstructurally by inducing a finer dispersion of monosulfate. PMID:26722191

  11. 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.

  12. 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.

  13. Electrically conductive anodized aluminum coatings (United States)

    Alwitt, Robert S. (Inventor); Liu, Yanming (Inventor)


    A process for producing anodized aluminum with enhanced electrical conductivity, comprising anodic oxidation of aluminum alloy substrate, electrolytic deposition of a small amount of metal into the pores of the anodized aluminum, and electrolytic anodic deposition of an electrically conductive oxide, including manganese dioxide, into the pores containing the metal deposit; and the product produced by the process.

  14. China’s Aluminum Resources

    Institute of Scientific and Technical Information of China (English)


    <正> The aluminum industry makes one of the keyindustries in China’s industrial and agriculturalmodernization and features a high degree ofrelevance with all industries.Of all the 124existing industries in China,113 use aluminum,representing an industrial relevance rate of91%.The consumption of aluminum is also ofhigh relevance with China’s GDP.

  15. 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.

  16. 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...

  17. Aluminum for Plasmonics (United States)


    in plasmon-enhanced light harvesting,14 photocatalysis ,511 surface- enhanced spectroscopies,1216 optics-based sensing,1722 nonlinear optics,2326...optical response of Al nanoparticles has appeared inconsistent relative to calculated spectra, even forwell-characterized geometries. Some studies have...model- ing their optical response. These results pro- vide a method for estimating the metallic purity of aluminum nanoparticles directly from their

  18. 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

  19. 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.

  20. 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.

  1. 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.

  2. 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

  3. 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.

  4. Synthesis and characterization of the aluminium phosphates modified with ammonium, calcium and molybdenum by hydrothermal method

    Directory of Open Access Journals (Sweden)

    Łuczka Kinga


    Full Text Available Synthesis and characterization of the aluminum phosphates modified with ammonium, calcium and molybdenum were conducted. The influence of process parameters (reactive pressure and molar ratios in the reaction mixture were studied. The contents of the individual components in the products were in the range of: 10.97–17.31 wt% Al, 2.65–13.32 wt% Ca, 0.70–3.11 wt% Mo, 4.36–8.38 wt% NH3, and 35.12–50.54 wt% P2O5. The materials obtained in the experiments were characterized by various physicochemical parameters. The absorption oil number was in the range from 67 to 89 of oil/100 g of product, the surface area was within the range of 4–76 m2/g, whereas the average particle size of products reached 282–370 nm. The Tafel tests revealed comparable anticorrosive properties of aluminum phosphates modified with ammonium, calcium, molybdenum in comparison with commercial phosphate.

  5. 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

  6. [Removal of Sulfate Ions from Aqueous Solution by Adsorption with Hydrotalcite- like Composite]. (United States)

    Gu, Yi-bing; Ma, Yong-wen; Wan, Jin-quan; Wang, Yan; Guan, Ze-yu


    Hydrotalcite-like composite synthesized by co-precipitation method was used as an adsorbent to remove the sulfate ions in aqueous solution. XRD, FT-IR , SEM and EDS elemental analysis were used to clarify the structure and composition of the hydrotalcite- like composite. The influences of time, initial pH value and coexisting ions on adsorption performance were investigated. The result showed the material was the composite of zinc aluminum nitrate hydrotalcite-like compounds and zinc aluminum phenylalanine hydrotalcite-like compounds. Hydrotalcite-like composite had a good performance in adsorption of sulfate ions, and the maximum adsorption capacity was 52.75 mg · g⁻¹. The data fitted pseudo-second order kinetic model best, which indicated that chemical adsorption was the rate-limiting step. Freundlich isotherm was more suitable to describe the adsorption process, and this meant the adsorption of sulfate ions by hydrotalcite-like composite was multilayered adsorption. Thermodynamic parameters showed that the adsorption process was endothermic and spontaneous at room temperature. Hydrotalcite-like composite adsorbed sulfate ions mainly through ion exchange, electrostatic force and physical adsorption. The experimental results showed that the hydrotalcite-like composite had potential for sulfate ion removal in the aqueous solution.

  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. Reactivity of Mg-Al hydrotalcites in solid and delaminated forms in ammonium carbonate solutions (United States)

    Stoica, Georgiana; Santiago, Marta; Abelló, Sònia; Pérez-Ramírez, Javier


    Treatment of Mg-Al hydrotalcites (LDHs, layered double hydroxides) in aqueous (NH 4) 2CO 3 at 298 K leads to composites of dawsonite, hydrotalcite, and magnesium ammonium carbonate. The mechanism and kinetics of this transformation, ultimately determining the relative amounts of these components in the composite, depend on the treatment time (from 1 h to 9 days), the Mg/Al ratio in the hydrotalcite (2-4), and on the starting layered double hydroxide (solid or delaminated form). The materials at various stages of the treatment were characterized by inductive coupled plasma-optical emission spectroscopy, X-ray diffraction, transmission electron microscopy, infrared spectroscopy, thermogravimetry, and nitrogen adsorption at 77 K. The progressive transformation of hydrotalcite towards crystalline dawsonite and magnesium ammonium carbonate phases follows a dissolution-precipitation mechanism. A gradual decrease of the Mg/Al ratio in the resulting solids was observed in time due to magnesium leaching in the reacting medium. Dawsonite-hydrotalcite composite formation is favored at high aluminum contents in the starting hydrotalcite, while the formation of magnesium ammonium carbonate is favored at high Mg/Al ratios. The synthetic strategy comprising hydrotalcite delamination in formamide prior to aqueous (NH 4) 2CO 3 treatment is more reactive towards composite formation than starting from the bulk solid hydrotalcite.

  10. Formation of ettringite, Ca 6Al 2(SO 4) 3(OH) 12·26H 2O, AFt, and monosulfate, Ca 4Al 2O 6(SO 4)·14H 2O, AFm-14, in hydrothermal hydration of Portland cement and of calcium aluminum oxide—calcium sulfate dihydrate mixtures studied by in situ synchrotron X-ray powder diffraction (United States)

    Christensen, Axel Nørlund; Jensen, Torben R.; Hanson, Jonathan C.


    In the hydration of calcium aluminum oxide-gypsum mixtures, i.e., Ca 3Al 2O 6, Ca 12Al 14O 33 and CaSO 4·2H 2O, the reaction products can be ettringite, Ca 6Al 2(SO 4) 3(OH) 12·26H 2O, monosulfate, Ca 4Al 2O 6(SO 4)·14H 2O, or the calcium aluminum oxide hydrate, Ca 4Al 2O 7·19H 2O. Ettringite is formed if sufficient CaSO 4·2H 2O is present in the mixture. Ettringite is converted to monosulfate when all CaSO 4·2H 2O is consumed in the synthesis of ettringite. The reactions were investigated in the temperature range 25-170°C using in situ synchrotron X-ray powder diffraction. This technique allows the study of very fast chemical reactions that are observed here under hydrothermal conditions. A new experimental approach was developed to perform in situ mixing of the reactants during X-ray data collection.

  11. 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

  12. 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

  13. 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

  14. 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.

  15. 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.

  16. 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.

  17. 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...

  18. Aluminum microstructures on anodic alumina for aluminum wiring boards. (United States)

    Jha, Himendra; Kikuchi, Tatsuya; Sakairi, Masatoshi; Takahashi, Hideaki


    The paper demonstrates simple methods for the fabrication of aluminum microstructures on the anodic oxide film of aluminum. The aluminum sheets were first engraved (patterned) either by laser beam or by embossing to form deep grooves on the surface. One side of the sheet was then anodized, blocking the other side by using polymer mask to form the anodic alumina. Because of the lower thickness at the bottom part of the grooves, the part was completely anodized before the complete oxidation of the other parts. Such selectively complete anodizing resulted in the patterns of metallic aluminum on anodic alumina. Using the technique, we fabricated microstructures such as line patterns and a simple wiring circuit-board-like structure on the anodic alumina. The aluminum microstructures fabricated by the techniques were embedded in anodic alumina/aluminum sheet, and this technique is promising for applications in electronic packaging and devices.

  19. Electrochemical formation of a composite polymer-aluminum oxide film (United States)

    Runge-Marchese, Jude Mary


    The formation of polymer films through electrochemical techniques utilizing electrolytes which include conductive polymer is of great interest to the coatings and electronics industries as a means for creating electrically conductive and corrosion resistant finishes. One of these polymers, polyamino-benzene (polyaniline), has been studied for this purpose for over ten years. This material undergoes an insulator-to-metal transition upon doping with protonic acids in an acid/base type reaction. Review of prior studies dealing with polyaniline and working knowledge of aluminum anodization has led to the development of a unique process whereby composite polymer-aluminum oxide films are formed. The basis for the process is a modification of the anodizing electrolyte which results in the codeposition of polyaniline during aluminum anodization. A second process, which incorporates electrochemical sealing of the anodic layer with polyaniline was also developed. The formation of these composite films is documented through experimental processing, and characterized by way of scientific analysis and engineering tests. Analysis results revealed the formation of unique dual phase anodic films with fine microstructures which exhibited full intrusion of the columnar aluminum oxide structure with polyaniline, indicating the polymer was deposited as the metal oxidation proceeded. An aromatic amine derivative of polyaniline with aluminum sulfate was determined to be the reaction product within the aluminum oxide phase of the codeposited films. Scientific characterization determined the codeposition process yields completely chemically and metallurgically bound composite films. Engineering studies determined the films, obtained through a single step, exhibited superior wear and corrosion resistance to conventionally anodized and sealed films processed through two steps, demonstrating the increased manufacturing process efficiency that can be realized with the modification of the

  20. 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.

  1. 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.

  2. 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

  3. 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.

  4. 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.

  5. 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

  6. Aluminum Carbothermic Technology

    Energy Technology Data Exchange (ETDEWEB)

    Bruno, Marshall J.


    This report documents the non-proprietary research and development conducted on the Aluminum Carbothermic Technology (ACT) project from contract inception on July 01, 2000 to termination on December 31, 2004. The objectives of the program were to demonstrate the technical and economic feasibility of a new carbothermic process for producing commercial grade aluminum, designated as the ''Advanced Reactor Process'' (ARP). The scope of the program ranged from fundamental research through small scale laboratory experiments (65 kW power input) to larger scale test modules at up to 1600 kW power input. The tasks included work on four components of the process, Stages 1 and 2 of the reactor, vapor recovery and metal alloy decarbonization; development of computer models; and economic analyses of capital and operating costs. Justification for developing a new, carbothermic route to aluminum production is defined by the potential benefits in reduced energy, lower costs and more favorable environmental characteristics than the conventional Hall-Heroult process presently used by the industry. The estimated metrics for these advantages include energy rates at approximately 10 kWh/kg Al (versus over 13 kWh/kg Al for Hall-Heroult), capital costs as low as $1250 per MTY (versus 4,000 per MTY for Hall-Heroult), operating cost reductions of over 10%, and up to 37% reduction in CO2 emissions for fossil-fuel power plants. Realization of these benefits would be critical to sustaining the US aluminum industries position as a global leader in primary aluminum production. One very attractive incentive for ARP is its perceived ability to cost effectively produce metal over a range of smelter sizes, not feasible for Hall-Heroult plants which must be large, 240,000 TPY or more, to be economical. Lower capacity stand alone carbothermic smelters could be utilized to supply molten metal at fabrication facilities similar to the mini-mill concept employed by the steel industry

  7. 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.

  8. Formulasi Sediaan Deodoran Antiperspiran Bentuk Batang (Stick) Dengan Aluminium Kalium Sulfat (Tawas)


    Lase, Bertha Dwi Julinta


    Background: Antiperspirant is a cosmetic which is used to suppress sweating by stricted pores of sweat glands, including eccrine and apocrine. Alum (potassium aluminum sulfate) is a traditional antiperspirant, which serves to improve body odor works by inhibiting the secretion of sweat with narrow the pores. In trade, alum is available in powder form antiperspirant deodorant. This form is less effective because it can be dissolved with sweat. Deodorant cosmetic preparations have several forms...

  9. 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...

  10. 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...

  11. 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....

  12. 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...

  13. Laser assisted foaming of aluminum

    Energy Technology Data Exchange (ETDEWEB)

    Kathuria, Y.P. [Laser X Co. Ltd., Aichi (Japan)


    Recently aluminum foams have evoked considerable interest as an alternative material owing to their wide range of applications ranging from microelectronics, through automobiles to aerospace industries. The manufacturing techniques and characterization methods for aluminum foams require further development to achieve effective and economical use of this material. In this communication the authors demonstrate the feasibility of unidirectional and localized expansion of the aluminum foam using the Nd-YAG/CO{sub 2} laser and powder metallurgy. (orig.)

  14. 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...

  15. 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...

  16. Effects of sucralfate and ranitidine on aluminum concentrations in elderly volunteers. (United States)

    Moore, J G; Coburn, J W; Sanders, M C; McSorley, D J; Sirgo, M A


    Elevated aluminum concentrations have been implicated in several disease states in the elderly. We examined the effects of sucralfate, a basic aluminum salt of sucrose sulfate, and ranitidine, administered individually and in combination, on plasma and urine aluminum concentrations in the elderly in a prospective, randomized, three-arm crossover study. Subjects were 20 healthy volunteers over age 65 years, with no clinically significant comorbidities or recent use of aluminum-containing drugs or histamine (H)2-antagonists. The three regimens were ranitidine 300 mg at bedtime, sucralfate 1 g 4 times/day, and ranitidine 300 mg at bedtime plus sucralfate 1 g 4 times/day, administered for 4 weeks, with a washout period of at least 1 week between regimens. Plasma and urine aluminum concentrations were measured on days 0, 1, 7, 14, and 28 of each regimen. After 28 days, mean plasma aluminum concentrations were significantly higher in subjects receiving sucralfate alone (8.5 +/- 1.8 micrograms/L) and sucralfate plus ranitidine (5.1 +/- 1.3 micrograms/L) compared with those receiving ranitidine alone (2.4 +/- 0.7 micrograms/L). Urine aluminum concentrations were significantly higher in subjects receiving sucralfate alone (133.2 +/- 32.8 micrograms/g creatinine) and sucralfate plus ranitidine (148.1 +/- 51.9 micrograms/g creatinine) compared with those receiving ranitidine alone (11.0 +/- 3.7 micrograms/g creatinine). There was no significant difference in plasma or urine aluminum concentrations between subjects who received sucralfate alone versus those who received sucralfate plus ranitidine. Sucralfate 4 g/day in elderly subjects produces a significant increase in both plasma and urine aluminum concentrations, compared with ranitidine 300 mg/day. This increase most likely is secondary to gastrointestinal absorption of aluminum in the sucralfate formulation. The clinical relevance of this increase requires further evaluation.

  17. 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

  18. 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.

  19. Neurofibrillary pathology and aluminum in Alzheimer's disease


    Shin, R. W.; Lee, V.M.Y.; Trojanowski, J.Q.


    Since the first reports of aluminum-induced neurofibrillary degeneration in experimental animals, extensive studies have been performed to clarify the role played by aluminum in the pathogenesis of Alzheimer's disease (AD). Additional evidence implicating aluminum in AD includes elevated levels of aluminum in the AD brain, epidemiological data linking aluminum exposure to AD, and interactions between aluminum and protein components in the pathological lesions o...

  20. Selective Adsorption of Sodium Aluminum Fluoride Salts from Molten Aluminum

    Energy Technology Data Exchange (ETDEWEB)

    Leonard S. Aubrey; Christine A. Boyle; Eddie M. Williams; David H. DeYoung; Dawid D. Smith; Feng Chi


    Aluminum is produced in electrolytic reduction cells where alumina feedstock is dissolved in molten cryolite (sodium aluminum fluoride) along with aluminum and calcium fluorides. The dissolved alumina is then reduced by electrolysis and the molten aluminum separates to the bottom of the cell. The reduction cell is periodically tapped to remove the molten aluminum. During the tapping process, some of the molten electrolyte (commonly referred as “bath” in the aluminum industry) is carried over with the molten aluminum and into the transfer crucible. The carryover of molten bath into the holding furnace can create significant operational problems in aluminum cast houses. Bath carryover can result in several problems. The most troublesome problem is sodium and calcium pickup in magnesium-bearing alloys. Magnesium alloying additions can result in Mg-Na and Mg-Ca exchange reactions with the molten bath, which results in the undesirable pickup of elemental sodium and calcium. This final report presents the findings of a project to evaluate removal of molten bath using a new and novel micro-porous filter media. The theory of selective adsorption or removal is based on interfacial surface energy differences of molten aluminum and bath on the micro-porous filter structure. This report describes the theory of the selective adsorption-filtration process, the development of suitable micro-porous filter media, and the operational results obtained with a micro-porous bed filtration system. The micro-porous filter media was found to very effectively remove molten sodium aluminum fluoride bath by the selective adsorption-filtration mechanism.

  1. 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.

  2. Aluminum Nanoholes for Optical Biosensing

    Directory of Open Access Journals (Sweden)

    Carlos Angulo Barrios


    Full Text Available Sub-wavelength diameter holes in thin metal layers can exhibit remarkable optical features that make them highly suitable for (biosensing applications. Either as efficient light scattering centers for surface plasmon excitation or metal-clad optical waveguides, they are able to form strongly localized optical fields that can effectively interact with biomolecules and/or nanoparticles on the nanoscale. As the metal of choice, aluminum exhibits good optical and electrical properties, is easy to manufacture and process and, unlike gold and silver, its low cost makes it very promising for commercial applications. However, aluminum has been scarcely used for biosensing purposes due to corrosion and pitting issues. In this short review, we show our recent achievements on aluminum nanohole platforms for (biosensing. These include a method to circumvent aluminum degradation—which has been successfully applied to the demonstration of aluminum nanohole array (NHA immunosensors based on both, glass and polycarbonate compact discs supports—the use of aluminum nanoholes operating as optical waveguides for synthesizing submicron-sized molecularly imprinted polymers by local photopolymerization, and a technique for fabricating transferable aluminum NHAs onto flexible pressure-sensitive adhesive tapes, which could facilitate the development of a wearable technology based on aluminum NHAs.

  3. Ballistic Evaluation of 2060 Aluminum (United States)


    experiments in Experimental Facilities (EFs) 108 and 106, as well as John Hogan of ARL/AMB, Hugh Walter of Bowhead Science and Technology, and David aluminum (Al)-based monocoque armored-vehicle hulls such as those of the M2 Bradley Infantry Fighting Vehicles. Also in 2012 the Aluminum

  4. 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.

  5. Wettability of Aluminum on Alumina (United States)

    Bao, Sarina; Tang, Kai; Kvithyld, Anne; Tangstad, Merete; Engh, Thorvald Abel


    The wettability of molten aluminum on solid alumina substrate has been investigated by the sessile drop technique in a 10-8 bar vacuum or under argon atmosphere in the temperature range from 1273 K to 1673 K (1000 °C to 1400 °C). It is shown that the reduction of oxide skin on molten aluminum is slow under normal pressures even with ultralow oxygen potential, but it is enhanced in high vacuum. To describe the wetting behavior of the Al-Al2O3 system at lower temperatures, a semiempirical calculation was employed. The calculated contact angle at 973 K (700 °C) is approximately 97 deg, which indicates that aluminum does not wet alumina at aluminum casting temperatures. Thus, a priming height is required for aluminum to infiltrate a filter. Wetting in the Al-Al2O3 system increases with temperature.

  6. 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.

  7. Hualu Aluminum Will Construct Large Coal-Power-Aluminum Aluminum Processing Industrial Chain

    Institute of Scientific and Technical Information of China (English)


    The reporter learned from relevant departments of Baiyin City that in order to further push forward industrial upgrading,fulfill expansion and consolidation of the enterprise,Gansu Hualu Aluminum Co.,Ltd(Hualu Aluminum)will implement Out-Of-City-Into-Park project,

  8. 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

  9. 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.

  10. 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....

  12. Spray Rolling Aluminum Strip

    Energy Technology Data Exchange (ETDEWEB)

    Lavernia, E.J.; Delplanque, J-P; McHugh, K.M.


    Spray forming is a competitive low-cost alternative to ingot metallurgy for manufacturing ferrous and non-ferrous alloy shapes. It produces materials with a reduced number of processing steps, while maintaining materials properties, with the possibility of near-net-shape manufacturing. However, there are several hurdles to large-scale commercial adoption of spray forming: 1) ensuring strip is consistently flat, 2) eliminating porosity, particularly at the deposit/substrate interface, and 3) improving material yield. Through this program, a new strip/sheet casting process, termed spray rolling, has been developed, which is an innovative manufacturing technique to produce aluminum net-shape products. Spray rolling combines the benefits of twin-roll casting and conventional spray forming, showing a promising potential to overcome the above hurdles associated with spray forming. Spray rolling requires less energy and generates less scrap than conventional processes and, consequently, enables the development of materials with lower environmental impacts in both processing and final products. Spray Rolling was developed as a collaborative project between the University of California-Davis, the Colorado School of Mines, the Idaho National Engineering and Environmental Laboratory, and an industry team. The following objectives of this project were achieved: (1) Demonstration of the feasibility of the spray rolling process at the bench-scale level and evaluation of the materials properties of spray rolled aluminum strip alloys; and (2) Demonstration of 2X scalability of the process and documentation of technical hurdles to further scale up and initiate technology transfer to industry for eventual commercialization of the process.

  13. 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.

  14. Sorbents based on xerogels of zirconium, aluminum and manganese oxyhydroxides

    Directory of Open Access Journals (Sweden)

    R.V. Smotraiev


    Full Text Available The actual problem of water supply in the world and in Ukraine, in particular, is a high level of pollution in water resources and an insufficient level of drinking water purification. With industrial wastewater, a significant amount of pollutants falls into water bodies, including suspended particles, sulfates, iron compounds, heavy metals, etc. Aim: The aim of this work is to determine the impact of aluminum and manganese ions additives on surface and sorption properties of zirconium oxyhydroxide based sorbents during their production process. Materials and Methods: The sorbents based on xerogels of zirconium, aluminum and manganese oxyhydroxides were prepared by sol-gel method during the hydrolysis of metal chlorides (zirconium oxychloride ZrOCl2, aluminum chloride AlCl3 and manganese chloride MnCl2 with carbamide. Results: The surface and sorption properties of sorbents based on xerogels of zirconium, aluminum and manganese oxyhydroxides were investigated. X-ray amorphous structure and evolved hydroxyl-hydrate cover mainly characterize the obtained xerogels. The composite sorbents based on xerogels of zirconium oxyhydroxide doped with aluminum oxyhydroxide (aS = 537 m2/g and manganese oxyhydroxide (aS = 356 m2/g have more developed specific surface area than single-component xerogels of zirconium oxyhydroxide (aS = 236 m2/g and aluminum oxyhydroxide (aS = 327 m2/g. The sorbent based on the xerogel of zirconium and manganese oxyhydroxides have the maximum SO42--ions sorption capacity. It absorbs 1.5 times more SO42–-ions than the industrial anion exchanger AN-221. The sorbents based on xerogels of zirconium oxyhydroxide has the sorption capacity of Fe3+-ions that is 1.5…2 times greater than the capacity of the industrial cation exchanger KU-2-8. The Na+-ions absorption capacity is 1.47…1.56 mmol/g for each sorbent. Conclusions: Based on these data it can be concluded that the proposed method is effective for sorbents production based on

  15. 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

  16. Subsurface Aluminum Nitride Formation in Iron-Aluminum Alloys (United States)

    Bott, June H.

    Transformation-induced plasticity (TRIP) steels containing higher amounts of aluminum than conventional steels are ideal for structural automotive parts due to their mechanical properties. However, the aluminum tends to react with any processing environment at high temperatures and therefore presents significant challenges during manufacturing. One such challenge occurs during secondary cooling, reheating, and hot-rolling and is caused by a reaction with nitrogen-rich atmospheres wherein subsurface aluminum nitride forms in addition to internal and external oxides. The nitrides are detrimental to mechanical properties and cause surface cracks. It is important to understand how these nitrides and oxides form and their consequences for the quality of steel products. This study looks at model iron-aluminum (up to 8 wt.% aluminum) alloys and uses confocal laser scanning microscopy, x-ray diffraction, scanning electron microscopy with energy dispersive x-ray spectrometry, and transmission electron microscopy to study the effect of various conditions on the growth and development of these precipitates in a subsurface oxygen-depleted region. By using model alloys and controlling the experimental atmosphere, this study is able to understand some of the more fundamental materials science behind aluminum nitride formation in aluminum-rich iron alloys and the relationship between internal nitride and oxide precipitation and external oxide scale morphology and composition. The iron-aluminum alloys were heated in N2 atmospheres containing oxygen impurities. It was found that nitrides formed when bulk aluminum content was below 8 wt.% when oxygen was sufficiently depleted due to the internal oxidation. In the samples containing 1 wt.% aluminum, the depth of the internal oxide and nitride zones were in agreement with a diffusion-based model. Increasing aluminum content to 3 and 5 wt% had the effects of modifying the surface-oxide scale composition and increasing its continuity

  17. 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

  18. Reuse of ammonium fluoride generated in the uranium hexafluoride conversion; Reutilizacao do fluoreto de amonio gerado na reconversao do hexafluoreto de uranio

    Energy Technology Data Exchange (ETDEWEB)

    Silva Neto, J.B.; Carvalho, E.F. Urano de; Durazzo, M., E-mail: jbsneto@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Riella, H.G [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil)


    The Nuclear Fuel Centre of IPEN / CNEN - SP develops and manufactures dispersion fuel with high uranium concentration to meet the demand of the IEA-R1 reactor and future research reactors planned to be constructed in Brazil. The fuel uses uranium silicide (U{sub 3}Si{sub 2}) dispersed in aluminum. For producing the fuel, the processes for uranium hexafluoride (UF{sub 6}) conversion consist in obtaining U{sub 3}Si{sub 2} and / or U{sub 3}O{sub 8} through the preparation of intermediate compounds, among them ammonium uranyl carbonate - AUC, ammonium diuranate - DUA and uranium tetrafluoride - UF{sub 4}. This work describes a procedure for preparing uranium tetrafluoride by a dry route using as raw material the filtrate generated when producing routinely ammonium uranyl carbonate. The filtrate consists primarily of a solution containing high concentrations of ammonium (NH{sub 4}{sup +}), fluoride (F{sup -}), carbonate (CO{sub 3}{sup --}) and low concentrations of uranium. The procedure is basically the recovery of NH{sub 4}F and uranium, as UF{sub 4}, through the crystallization of ammonium bifluoride (NH{sub 4}HF{sub 2}) and, in a later step, the addition of UO{sub 2}, occurring fluoridation and decomposition. The UF{sub 4} obtained is further diluted in the UF{sub 4} produced routinely at IPEN / CNEN-SP by a wet route process. (author)

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. Treatment of effluents of poultry slaughterhouse with aluminum salts and natural polyelectrolytes. (United States)

    Ikeda, E; Rodrigues, D G; Nozaki, J


    A mixture of aluminum salts and natural polyelectrolytes, extracted from the cactus Opuntia ficus indica, has been used for cleaning of wastewater from poultry slaughterhouse. The aggregation and settling properties of colloids and complex organics such as oil, grease, fats, proteins, and suspended solids, was increased if compared with conventional methods of wastewater treatment using only aluminum or iron sulfate. A mixture of aluminum salt in a concentration range of 300 to 600 mg l(-1) and natural polyelectrolytes of 0.6 to 0.8 mg l(-1) was used for flocculation and coagulation. The combination of coagulant and natural polyelectrolytes was able to remove chemical oxygen demand (86%), oil and grease (93%), turbidity (89%), and suspended solids (93%). Methanization activity was also investigated for the effluents in natura.

  4. An Update on Toxicology of Aluminum Phosphide

    Directory of Open Access Journals (Sweden)

    Ali Akbar Moghhadamnia


    Full Text Available Aluminum phosphide (AlP is a cheap solid fumigant and a highly toxic pesticide which is commonly used for grain preservation. In Iran it is known as the "rice tablet". AlP has currently aroused interest with increasing number of cases in the past four decades due to increased use in agricultural and non-agricultural purposes and also its easy availability in the markets has increased its misuse to commit suicide. Upon contact with moisture in the environment, AlP undergoes a chemical reaction yielding phosphine gas, which is the active pesticidal component. Phosphine inhibits cellular oxygen utilization and can induce lipid peroxidation. It was reported that AlP has a mortality rate more than 50% of intoxication cases. Poisoning with AlP has usually occurred in attempts to suicide. It is a more common case in adults rather than teen agers. In some eastern countries it is a very common agent with rapid action for suicide. Up to date, there is no effective antidote or treatment for its intoxication. Also, some experimental results suggest that magnesium sulfate, N-acetyl cysteine (NAC, glutathione, vitamin C and E, beta-carotenes, coconut oil and melatonin may play an important role in reducing the oxidative outcomes of phosphine. This article reviews the experimental and clinical features of AlP intoxication and tries to suggest a way to encounter its poisoning.

  5. An update on toxicology of aluminum phosphide

    Directory of Open Access Journals (Sweden)

    Moghadamnia Ali


    Full Text Available Abstract Aluminum phosphide (AlP is a cheap solid fumigant and a highly toxic pesticide which is commonly used for grain preservation. In Iran it is known as the “rice tablet”. AlP has currently aroused interest with increasing number of cases in the past four decades due to increased use in agricultural and non-agricultural purposesand also its easy availability in the markets has increased its misuse to commit suicide. Upon contact with moisture in the environment, AlP undergoes a chemical reaction yielding phosphine gas, which is the active pesticidal component. Phosphine inhibits cellular oxygen utilization and can induce lipid peroxidation. It was reported that AlP has a mortality rate more than 50% of intoxication cases. Poisoning with AlP has usually occurred in attempts to suicide. It is a more common case in adults rather than teen agers. In some eastern countries it is a very common agent with rapid action for suicide. Up to date, there is no effective antidote or treatment for its intoxication. Also, some experimental results suggest that magnesium sulfate, N-acetyl cysteine (NAC, glutathione, vitamin C and E, beta-carotenes, coconut oil and melatonin may play an important role in reducing the oxidative outcomes of phosphine. This article reviews the experimental and clinical features of AlP intoxication and tries to suggest a way to encounter its poisoning.

  6. An update on toxicology of aluminum phosphide (United States)


    Aluminum phosphide (AlP) is a cheap solid fumigant and a highly toxic pesticide which is commonly used for grain preservation. In Iran it is known as the “rice tablet”. AlP has currently aroused interest with increasing number of cases in the past four decades due to increased use in agricultural and non-agricultural purposesand also its easy availability in the markets has increased its misuse to commit suicide. Upon contact with moisture in the environment, AlP undergoes a chemical reaction yielding phosphine gas, which is the active pesticidal component. Phosphine inhibits cellular oxygen utilization and can induce lipid peroxidation. It was reported that AlP has a mortality rate more than 50% of intoxication cases. Poisoning with AlP has usually occurred in attempts to suicide. It is a more common case in adults rather than teen agers. In some eastern countries it is a very common agent with rapid action for suicide. Up to date, there is no effective antidote or treatment for its intoxication. Also, some experimental results suggest that magnesium sulfate, N-acetyl cysteine (NAC), glutathione, vitamin C and E, beta-carotenes, coconut oil and melatonin may play an important role in reducing the oxidative outcomes of phosphine. This article reviews the experimental and clinical features of AlP intoxication and tries to suggest a way to encounter its poisoning. PMID:23351193

  7. 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....

  8. 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....

  9. 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...

  10. 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....

  11. 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...

  12. 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.

  13. Preparing of Manganese Sulfate From Manganiferous Wastewater Yielded in Cobalt Salt Production%钴盐生产过程中含锰废水制备硫酸锰的工艺研究

    Institute of Scientific and Technical Information of China (English)

    贺剑明; 李婵君; 肖利; 庄建华; 定强


    In the process of preparing of cobalt salt using heterogenite ,the wastewater which contains heavy metal ions such as M n2+ ,Cu2+ ,Co2+ ,Zn2+ was produced .By four-stages purification and solvent extracting ,manganese sulfate which could be applied in battery materials was obtained .In the first stage ,Cu2+ ,Co2+ ,Zn2+ are precipitated by sodium sulphide ,the optimum amounts of sodium sulphide is 60 g/L .In the second stage ,ammonium bicarbonate is used to adjust pH for hydrolytic precipitation aluminum .In the third stage ,sodium sulphate is used to remove Ca2+ ,the ideal amounts of sodium sulphate is 110 g/L .In the fourth stage ,Al3+ ,Ca2+ can be further purified by adding sodium fluoride , the best amount of sodium fluoride is 0 .45 g/L .After the above four steps ,manganese sulfate was obtained by P204-extraction and H2 SO4 anti-extraction ,evaporation and crystallization ,manganese sulfate used as battery materials can be obtained .%针对水钴矿制备钴盐生产过程中含锰、铜、钴、锌等重金属离子废水,通过4步除杂、P204萃取富集锰,制备电池材料用硫酸锰。第1步用硫化钠去除铜、钴、锌离子,硫化钠最佳加入量为60 g/L ;第2步用碳酸氢铵调pH去除铝,最佳pH为4.5;第3步用硫酸钠去除Ca2+,硫酸钠最佳用量为110 g/L ;第4步用氟化钠进一步去除Al3+和Ca2+,氟化钠最佳用量为0.45 g/L。4步除杂后的废水用P204萃取、硫酸反萃取,得到硫酸锰溶液,硫酸锰溶液经蒸发结晶得到电池材料用硫酸锰。

  14. 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.

  15. Invisible Display in Aluminum

    DEFF Research Database (Denmark)

    Prichystal, Jan Phuklin; Hansen, Hans Nørgaard; Bladt, Henrik Henriksen


    Bang & Olufsen a/s has been working with ideas for invisible integration of displays in metal surfaces. Invisible integration of information displays traditionally has been possible by placing displays behind transparent or semitransparent materials such as plastic or glass. The wish for an integ...... be obtained by shining light from the backside of the workpiece. When there is no light from the backside, the front surface seems totally untouched. This was achieved by laser ablation with ultra-short pulses.......Bang & Olufsen a/s has been working with ideas for invisible integration of displays in metal surfaces. Invisible integration of information displays traditionally has been possible by placing displays behind transparent or semitransparent materials such as plastic or glass. The wish...... for an integrated display in a metal surface is often ruled by design and functionality of a product. The integration of displays in metal surfaces requires metal removal in order to clear the area of the display to some extent. The idea behind an invisible display in Aluminum concerns the processing of a metal...

  16. Anodized aluminum on LDEF (United States)

    Golden, Johnny L.


    A compilation of reported analyses and results obtained for anodized aluminum flown on the Long Duration Exposure Facility (LDEF) was prepared. Chromic acid, sulfuric acid, and dyed sulfuric acid anodized surfaces were exposed to the space environment. The vast majority of the anodized surface on LDEF was chromic acid anodize because of its selection as a thermal control coating for use on the spacecraft primary structure, trays, tray clamps, and space end thermal covers. Reports indicate that the chromic acid anodize was stable in solar absorptance and thermal emittance, but that contamination effects caused increases in absorptance on surfaces exposed to low atomic oxygen fluences. There were some discrepancies, however, in that some chromic acid anodized specimens exhibited significant increases in absorptance. Sulfuric acid anodized surfaces also appeared stable, although very little surface area was available for evaluation. One type of dyed sulfuric acid anodize was assessed as an optical baffle coating and was observed to have improved infrared absorptance characteristics with exposure on LDEF.


    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%.


    Energy Technology Data Exchange (ETDEWEB)

    Fox, K.; Edwards, T.


    This report describes the results of studies related to the incorporation of sulfate in high level waste (HLW) borosilicate glass produced at the Savannah River Site (SRS) Defense Waste Processing Facility (DWPF). A group of simulated HLW glasses produced for earlier sulfate retention studies was selected for full chemical composition measurements to determine whether there is any clear link between composition and sulfate retention over the compositional region evaluated. In addition, the viscosity of several glasses was measured to support future efforts in modeling sulfate solubility as a function of predicted viscosity. The intent of these studies was to develop a better understanding of sulfate retention in borosilicate HLW glass to allow for higher loadings of sulfate containing waste. Based on the results of these and other studies, the ability to improve sulfate solubility in DWPF borosilicate glasses lies in reducing the connectivity of the glass network structure. This can be achieved, as an example, by increasing the concentration of alkali species in the glass. However, this must be balanced with other effects of reduced network connectivity, such as reduced viscosity, potentially lower chemical durability, and in the case of higher sodium and aluminum concentrations, the propensity for nepheline crystallization. Future DWPF processing is likely to target higher waste loadings and higher sludge sodium concentrations, meaning that alkali concentrations in the glass will already be relatively high. It is therefore unlikely that there will be the ability to target significantly higher total alkali concentrations in the glass solely to support increased sulfate solubility without the increased alkali concentration causing failure of other Product Composition Control System (PCCS) constraints, such as low viscosity and durability. No individual components were found to provide a significant improvement in sulfate retention (i.e., an increase of the magnitude

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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...

  5. Gas evolution behavior of aluminum in mortar

    Energy Technology Data Exchange (ETDEWEB)

    Hashizume, Shuji; Matsumoto, Junko; Banba, Tsunetaka [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment


    As a part of study of leaching behavior for solidified dry low level radioactive waste, gas evolution behavior of aluminum in mortar was investigated, and a plan of our research was proposed. The effect of pH on corrosion rate of aluminum, corrosion product, time dependency of corrosion rate of aluminum in mortar, change of corrosion mechanism, the effects of Na, Ca and Cl ions on corrosion rate of aluminum in mortar and corrosion behavior of aluminum when aluminum was used as sacrificed anode in reinforced concrete were previously clarified. Study of the effects of environmental factors such as pH, kind of ions and temperature on gas evolution behavior of aluminum and the effect of aluminum/carbon steel surface ratio no gas evolution behavior of aluminum were planed. (author). 75 refs.

  6. Low-aluminum content iron-aluminum alloys

    Energy Technology Data Exchange (ETDEWEB)

    Sikka, V.K.; Goodwin, G.M.; Alexander, D.J. [and others


    The low-aluminum-content iron-aluminum program deals with the development of a Fe-Al alloy with aluminum content such as a produce the minimum environmental effect at room temperature. The FAPY is an Fe-16 at. % Al-based alloy developed at the Oak Ridge National Laboratory as the highest aluminum-containing alloy with essentially no environmental effect. The chemical composition for FAPY in weight percent is: aluminum = 8.46, chromium = 5.50, zirconium = 0.20, carbon = 0.03, molybdenum = 2.00, yttrium = 0.10 and iron = 83.71. The ignots of the alloy can be hot worked by extrusion, forging, and rolling processes. The hot-worked cast structure can be cold worked with intermediate anneals at 800{degrees}C. Typical room-temperature ductility of the fine-grained wrought structure is 20 to 25% for this alloy. In contrast to the wrought structure, the cast ductility at room temperature is approximately 1% with a transition temperature of approximately 100 to 150{degrees}C, above which ductility values exceed 20%. The alloy has been melted and processed into bar, sheet, and foil. The alloy has also been cast into slabs, step-blocks of varying thicknesses, and shapes. The purpose of this section is to describe the welding response of cast slabs of three different thicknesses of FAPY alloy. Tensile, creep, and Charpy-impact data of the welded plates are also presented.

  7. 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...

  8. 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

  9. 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.

  10. 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.

  11. 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.

  12. Exraction and separation of CERIUM(IV)/FLUORINE in fluoride-bearing cerium sulfate solution with fluoride coordination agent


    Li, Y; J. G. He; X. X. Xue; Ru, H. Q.; X. W. Huang; Yang, H.


    In this paper the extraction and separation of cerium/fluorine in fluoride-bearing cerium sulfate solution with fluoride coordination agent has been studied. The UV-vis spectra suggest that Zr6+ and Al3+ can scrub the F- from [CeF2] 2+ complex. The separation and conductivity studies show that aluminum salt is the most suitable fluoride coordination agent, and an ion-exchange reaction is involved between Ce4+/ [CeF2] 2+ and hydrogen ion.

  13. Chemical stability of γ-butyrolactone-based electrolytes for aluminum electrolytic capacitors (United States)

    Ue, Makoto; Takeda, Masayuki; Suzuki, Yoko; Mori, Shoichiro

    γ-Butyrolactone-based electrolytes have been used as the operating electrolytes for aluminum electrolytic capacitors. The chemical stability of these electrolytes at elevated temperatures has been examined by monitoring the decrease in their electrolytic conductivities. The deteriorated electrolytes were analyzed by gas and liquid chromatography and the conductivity decrease was directly correlated with the loss of acid components. In quaternary ammonium hydrogen maleate/γ-butyrolactone electrolytes, the maleate anion decomposed by decarboxylation resulting in a complex polymer containing polyester and polyacrylate structures. Quaternary ammonium benzoate/γ-butyrolactoneelectrolytes decomposed by SN2 reactions giving alkyi benzoates and trialkylamines. The deterioration of the carboxylate salt/γ-butyrolactone electrolytes was accelerated by electrolysis.

  14. Scaleable Clean Aluminum Melting Systems

    Energy Technology Data Exchange (ETDEWEB)

    Han, Q.; Das, S.K. (Secat, Inc.)


    The project entitled 'Scaleable Clean Aluminum Melting Systems' was a Cooperative Research and Development Agreements (CRADAs) between Oak Ridge National Laboratory (ORNL) and Secat Inc. The three-year project was initially funded for the first year and was then canceled due to funding cuts at the DOE headquarters. The limited funds allowed the research team to visit industrial sites and investigate the status of using immersion heaters for aluminum melting applications. Primary concepts were proposed on the design of furnaces using immersion heaters for melting. The proposed project can continue if the funding agency resumes the funds to this research. The objective of this project was to develop and demonstrate integrated, retrofitable technologies for clean melting systems for aluminum in both the Metal Casting and integrated aluminum processing industries. The scope focused on immersion heating coupled with metal circulation systems that provide significant opportunity for energy savings as well as reduction of melt loss in the form of dross. The project aimed at the development and integration of technologies that would enable significant reduction in the energy consumption and environmental impacts of melting aluminum through substitution of immersion heating for the conventional radiant burner methods used in reverberatory furnaces. Specifically, the program would couple heater improvements with furnace modeling that would enable cost-effective retrofits to a range of existing furnace sizes, reducing the economic barrier to application.

  15. 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....

  16. 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...

  17. 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.

  18. Empirical Data Confirm Autism Symptoms Related to Aluminum and Acetaminophen Exposure

    Directory of Open Access Journals (Sweden)

    Jingjing Liu


    Full Text Available Autism is a condition characterized by impaired cognitive and social skills, associated with compromised immune function. The incidence is alarmingly on the rise, and environmental factors are increasingly suspected to play a role. This paper investigates word frequency patterns in the U.S. CDC Vaccine Adverse Events Reporting System (VAERS database. Our results provide strong evidence supporting a link between autism and the aluminum in vaccines. A literature review showing toxicity of aluminum in human physiology offers further support. Mentions of autism in VAERS increased steadily at the end of the last century, during a period when mercury was being phased out, while aluminum adjuvant burden was being increased. Using standard log-likelihood ratio techniques, we identify several signs and symptoms that are significantly more prevalent in vaccine reports after 2000, including cellulitis, seizure, depression, fatigue, pain and death, which are also significantly associated with aluminum-containing vaccines. We propose that children with the autism diagnosis are especially vulnerable to toxic metals such as aluminum and mercury due to insufficient serum sulfate and glutathione. A strong correlation between autism and the MMR (Measles, Mumps, Rubella vaccine is also observed, which may be partially explained via an increased sensitivity to acetaminophen administered to control fever.

  19. Chemical equilibrium modeling of organic acids, pH, aluminum, and iron in Swedish surface waters. (United States)

    Sjöstedt, Carin S; Gustafsson, Jon Petter; Köhler, Stephan J


    A consistent chemical equilibrium model that calculates pH from charge balance constraints and aluminum and iron speciation in the presence of natural organic matter is presented. The model requires input data for total aluminum, iron, organic carbon, fluoride, sulfate, and charge balance ANC. The model is calibrated to pH measurements (n = 322) by adjusting the fraction of active organic matter only, which results in an error of pH prediction on average below 0.2 pH units. The small systematic discrepancy between the analytical results for the monomeric aluminum fractionation and the model results is corrected for separately for two different fractionation techniques (n = 499) and validated on a large number (n = 3419) of geographically widely spread samples all over Sweden. The resulting average error for inorganic monomeric aluminum is around 1 µM. In its present form the model is the first internally consistent modeling approach for Sweden and may now be used as a tool for environmental quality management. Soil gibbsite with a log *Ks of 8.29 at 25°C together with a pH dependent loading function that uses molar Al/C ratios describes the amount of aluminum in solution in the presence of organic matter if the pH is roughly above 6.0.

  20. 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.

  1. Detailed analysis of a quench bomb for the study of aluminum agglomeration in solid propellants (United States)

    Gallier, S.; Kratz, J.-G.; Quaglia, N.; Fouin, G.


    A standard quench bomb (QB) - widely used to characterize condensed phase from metalized solid propellant combustion - is studied in detail. Experimental and numerical investigations proved that collected particles are mostly unburned aluminum (Al) agglomerates despite large quenching distances. Particles are actually found to quench early as propellant surface is swept by inert pressurant. Further improvements of the QB are proposed which allow measuring both Al agglomerates and alumina residue with the same setup. Finally, the results obtained on a typical aluminized ammonium perchlorate (AP) / hydroxyl-terminated polybutadiene (HTPB) propellant are briefly discussed.

  2. Decreasing residual aluminum level in drinking water

    Institute of Scientific and Technical Information of China (English)

    王志红; 崔福义


    The relativity of coagulant dosage, residual turbidity, temperature, pH etc. with residual aluminum concentration were investigated, and several important conclusions were achieved. Firstly, dosage of alum-coagulant or PAC1 influences residual aluminum concentration greatly. There is an optimal-dosage-to-aluminum, a bit less than the optimal-dosage-to-turbidity. Secondly, it proposes that decreasing residual aluminum concentration can be theoretically divided into two methods, either decreasing (even removing) the concentration of particulate aluminum component, or decreasing dissolved aluminum. In these tests there is an optimal value of residual turbidity of postprecipitation at 7.0 NTU. Thirdly, residual aluminum level will increase while water temperature goes higher. At the last, optimal pH value corresponds a minimum dissolved aluminum at a given turbidity. Data shows the optimal pH value decreases with water temperature's increasing.

  3. 21 CFR 172.310 - Aluminum nicotinate. (United States)


    ... Special Dietary and Nutritional Additives § 172.310 Aluminum nicotinate. Aluminum nicotinate may be safely... additive, expressed as niacin, shall appear on the label of the food additive container or on that of...

  4. Environmental Control over the Primary Aluminum Industry

    Institute of Scientific and Technical Information of China (English)


    <正> To strengthen environmental control over theprimary aluminum industry,the State Environ-mental Protection Administration of China hasrecently issued a notice addressing the follow-ing points:Strengthening environmental control over theexisting primary aluminum companies


    Directory of Open Access Journals (Sweden)

    Mohammed Ali Hajeeh


    Full Text Available Minimizing the amount of scrap generated in an aluminum extrusion process. An optimizing model is constructed in order to select the best cutting patterns of aluminum logs and billets of various sizes and shapes. The model applied to real data obtained from an existing extrusion factory in Kuwait. Results from using the suggested model provided substantial reductions in the amount of scrap generated. Using sound mathematical approaches contribute significantly in reducing waste and savings when compared to the existing non scientific techniques.

  6. Preparation of nano-sized hydrophilic aluminum fins coating materials for air conditioner

    Institute of Scientific and Technical Information of China (English)

    陈志明; 韩峰; 邵利


    Semicontinuous seeded emulsion copolymerization of acrylic acid, acrylamide and divinylbenzene was carried out at 80℃ with ammonium persulphate as the initiator and the polyether with comb configuration as the emulsifier to prepare approximately mono-dispersed nano-sized polymer particles with average diameter 90nm. The particles were used to combine with special polyether and de-ionized water was added to obtain nano-sized hydrophilic aluminum fins coating materials with solid content of 10%. The aluminum fins were coated with the materials to get the film showing self-assembly properties in some degree. The obtained hydrophilic fins have contact angles <5° with de-ionized water, minimum value 0°, after 4 cycles of wet and dry, contact angles <10° with de-ionized water.

  7. The effect of zinc on the aluminum anode of the aluminum-air battery (United States)

    Tang, Yougen; Lu, Lingbin; Roesky, Herbert W.; Wang, Laiwen; Huang, Baiyun

    Aluminum is an ideal material for batteries, due to its excellent electrochemical performance. Herein, the effect of zinc on the aluminum anode of the aluminum-air battery, as an additive for aluminum alloy and electrolytes, has been studied. The results show that zinc can decrease the anodic polarization, restrain the hydrogen evolution and increase the anodic utilization rate.

  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. Electrochemical Behavior of Aluminum in Nitric Acid

    Institute of Scientific and Technical Information of China (English)

    CHEN; Hui; ZHU; Li-yang; LIN; Ru-shan; TAN; Hong-bin; HE; Hui


    Aluminum is one of cladding materials for nuclear fuel,it is important to investigate the electrolytic dissolution of aluminum in nitric acid.The electrochemical impedance spectroscopy,polarization curve and cyclic voltammetry cure of anodic aluminum electrode in nitric acid under various conditions were collected(Fig.1).It turns out,under steady state,the thickness of the passivated film of aluminum

  11. 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

  12. [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.

  13. 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.

  14. 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.

  15. 76 FR 23490 - Aluminum tris (O (United States)


    ... AGENCY 40 CFR Part 180 Aluminum tris (O-ethylphosphonate), Butylate, Chlorethoxyfos, Clethodim, et al..., fosthiazate, propetamphos, and tebufenozide; the fungicide aluminum tris (O-ethylphosphonate); the herbicides.... Also, EPA is revoking the tolerances for aluminum tris (O-ethylphosphonate) on pineapple fodder...

  16. Guangxi Aluminum Giant Made Investment in Changfeng

    Institute of Scientific and Technical Information of China (English)


    <正>A aluminum processing and supporting project (450,000 tons) of Hefei Guangyin Aluminum Company kicked off in Xiatang Town of Changfeng County recently. It is a project jointly invested by Guangxi Investment Group and Guangxi Baise Guangyin Aluminum in Xiatang Town of Changfeng County.

  17. Structure and thermal decomposition of sulfated β-cyclodextrin intercalated in a layered double hydroxide (United States)

    Wang, Ji; Wei, Min; Rao, Guoying; Evans, David G.; Duan, Xue


    The sodium salt of hexasulfated β-cyclodextrin has been synthesized and intercalated into a magnesium-aluminum layered double hydroxide by ion exchange. The structure, composition and thermal decomposition behavior of the intercalated material have been studied by variable temperature X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), inductively coupled plasma emission spectroscopy (ICP), and thermal analysis (TG-DTA) and a model for the structure has been proposed. The thermal stability of the intercalated sulfated β-cyclodextrin is significantly enhanced compared with the pure form before intercalation.

  18. 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.

  19. Removing hydrochloric acid exhaust products from high performance solid rocket propellant using aluminum-lithium alloy. (United States)

    Terry, Brandon C; Sippel, Travis R; Pfeil, Mark A; Gunduz, I Emre; Son, Steven F


    Hydrochloric acid (HCl) pollution from perchlorate based propellants is well known for both launch site contamination, as well as the possible ozone layer depletion effects. Past efforts in developing environmentally cleaner solid propellants by scavenging the chlorine ion have focused on replacing a portion of the chorine-containing oxidant (i.e., ammonium perchlorate) with an alkali metal nitrate. The alkali metal (e.g., Li or Na) in the nitrate reacts with the chlorine ion to form an alkali metal chloride (i.e., a salt instead of HCl). While this technique can potentially reduce HCl formation, it also results in reduced ideal specific impulse (ISP). Here, we show using thermochemical calculations that using aluminum-lithium (Al-Li) alloy can reduce HCl formation by more than 95% (with lithium contents ≥15 mass%) and increase the ideal ISP by ∼7s compared to neat aluminum (using 80/20 mass% Al-Li alloy). Two solid propellants were formulated using 80/20 Al-Li alloy or neat aluminum as fuel additives. The halide scavenging effect of Al-Li propellants was verified using wet bomb combustion experiments (75.5±4.8% reduction in pH, ∝ [HCl], when compared to neat aluminum). Additionally, no measurable HCl evolution was detected using differential scanning calorimetry coupled with thermogravimetric analysis, mass spectrometry, and Fourier transform infrared absorption.

  20. Influence quaternary ammonium salt in the organophilization of an bentonite; Influencia de um sal quaternario de amonio na organofilizacao de uma argila bentonitica

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, S.V.; Alves, G.P.; Wanderley, A.S.D.; Araujo, E.M., E-mail: [Universidade Federal de Campina Grande (UFCG), Campina Grande, PB (Brazil). Depto de Engenharia de Materiais


    Clays are natural materials, earthy, fine-grained particles with diameters generally less than 2μm, and formed by chemically hydrated silicates of aluminum, iron and magnesium. The clays have a range of applications, both in pottery and in other technology areas. This work aimed to study the influence of a quaternary ammonium salt to increase the basal distance of a bentonite clay powder obtained thereby promoting to a new structural profile characteristic with organoclay. The bentonite clay was treated with salt Praepragem WB. The following methods were used: X-ray diffraction (XRD) and X-ray fluorescence (XRF). The results indicated the intercalation of ammonium ions of the salt studied within the layers of silicate and expansion of basal spacing d{sub 001}, ie the clay in the study showed 2θ angle shifts to smaller angles, indicating that the clay was organophilization. (author)

  1. 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

  2. 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

  3. Luminescent properties of aluminum hydride

    Energy Technology Data Exchange (ETDEWEB)

    Baraban, A.P.; Gabis, I.E.; Dmitriev, V.A. [Saint-Petersburg State University, Department of Physics, Saint-Petersburg 198504 (Russian Federation); Dobrotvorskii, M.A., E-mail: [Saint-Petersburg State University, Department of Physics, Saint-Petersburg 198504 (Russian Federation); Kuznetsov, V.G. [Saint-Petersburg State University, Department of Physics, Saint-Petersburg 198504 (Russian Federation); Matveeva, O.P. [National Mineral Resources University, Saint Petersburg 199106 (Russian Federation); Titov, S.A. [Petersburg State University of Railway Transport, Saint-Petersburg 190031 (Russian Federation); Voyt, A.P.; Elets, D.I. [Saint-Petersburg State University, Department of Physics, Saint-Petersburg 198504 (Russian Federation)


    We studied cathodoluminescence and photoluminescence of α-AlH{sub 3}– a likely candidate for use as possible hydrogen carrier in hydrogen-fueled vehicles. Luminescence properties of original α-AlH{sub 3} and α-AlH{sub 3} irradiated with ultraviolet were compared. The latter procedure leads to activation of thermal decomposition of α-AlH{sub 3} and thus has a practical implementation. We showed that the original and UV-modified aluminum hydride contain luminescence centers ‐ structural defects of the same type, presumably hydrogen vacancies, characterized by a single set of characteristic bands of radiation. The observed luminescence is the result of radiative intracenter relaxation of the luminescence center (hydrogen vacancy) excited by electrons or photons, and its intensity is defined by the concentration of vacancies, and the area of their possible excitation. UV-activation of the dehydrogenation process of aluminum hydride leads to changes in the spatial distribution of the luminescence centers. For short times of exposure their concentration increases mainly in the surface regions of the crystals. At high exposures, this process extends to the bulk of the aluminum hydride and ends with a decrease in concentration of luminescence centers in the surface region. - Highlights: • Aluminum hydride contains hydrogen vacancies which serve as luminescence centers. • The luminescence is the result of radiative relaxation of excited centers. • Hydride UV-irradiation alters distribution and concentration of luminescence centers.

  4. Aluminum break-point contacts

    NARCIS (Netherlands)

    Heinemann, Martina; Groot, R.A. de


    Ab initio molecular dynamics is used to study the contribution of a single Al atom to an aluminum breakpoint contact during the final stages of breaking and the initial stages of the formation of such a contact. A hysteresis effect is found in excellent agreement with experiment and the form of the

  5. 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...

  6. 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

  7. 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

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. {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.

  13. 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

  14. 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...

  15. 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。

  16. 钼酸铵润滑添加剂的摩擦学性能研究%Study on Tribological Behavior of Ammonium Molybdate Lubricant Additive

    Institute of Scientific and Technical Information of China (English)

    张玉伟; 丁旭; 孙丽华; 骆梅; 王雪


    Ammonium molybdate were modified separately with KH 550 and aluminum-zirconium coupling agent .The anti-wear and friction behavior of the base oil with modified ammonium molybdate were studied with four -ball instrument. The result showed that anti-friction reducing performance of ammonium molybdate modified separately with KH 550 and aluminum-zirconium coupling agent was not obvious .But it had good wear resistance performance , ammonium molybdate modified with aluminum-zirconium coupling agent was better .Compared with base oil , the wear scar diameter was decreased by 22%, when adding amount was about 0.2%.Grease doped with 3%ammonium molybdate had better wear resistance , the wear scar diameter was increased by 51%.The extreme pressure performance was also improved .%采用硅烷( KH550)和铝锆两种偶联剂对钼酸铵进行表面修饰。将含修饰的钼酸铵润滑油在四球摩擦磨损试验机上研究其摩擦磨损性能。研究显示:含铝锆和硅烷修饰的钼酸铵基础油的减摩性能不明显,但具有较好的抗磨效果,其中铝锆修饰的钼酸铵抗磨性能更佳;在长磨实验中,质量分数为0.2%的钼酸铵润滑油与基础油相比,磨斑直径降低约22%;在润滑脂中钼酸铵的质量分数为3%时有较佳的抗磨性能,钢球的磨斑直径较基础脂下降约51%,抗极压性能也有所提高。

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. Multilayer Clad Plate of Stainless Steel/Aluminum/Aluminum Alloy

    Institute of Scientific and Technical Information of China (English)

    YUAN Jiawei; PANG Yuhua; LI Ting


    The 3, 5, 20 layer clad plate from austenitic stainless steel, pure aluminum and aluminum alloy sheets were fabricated in different ways. The stretch and interface properties were measured. The result shows that 20 layer clad plate is better than the others. Well-bonded clad plate was successfully obtained in the following procedure: Basic clad sheet from 18 layer A11060/A13003sheets was firstly obtained with an initial rolling reduction of 44% at 450 ℃, followed by annealing at 300 ℃, and then with reduction of 50% at 550 ℃ from STS304 on each side. The best 20 layer clad plate was of 129 MPa bonding strength and 225 MPa stretch strength.

  3. Electrodeposition of aluminum on aluminum surface from molten salt

    Institute of Scientific and Technical Information of China (English)

    Wenmao HUANG; Xiangyu XIA; Bin LIU; Yu LIU; Haowei WANG; Naiheng MA


    The surface morphology,microstructure and composition of the aluminum coating of the electrodeposition plates in AlC13-NaC1-KC1 molten salt with a mass ratio of 8:1:1 were investigated by SEM and EDS.The binding force was measured by splat-cooling method and bending method.The results indicate that the coatings with average thicknesses of 12 and 9 μm for both plates treated by simple grinding and phosphating are compacted,continuous and well adhered respectively. Tetramethylammonium chloride (TMAC) can effectively prevent the growth of dendritic crystal,and the anode activation may improve the adhesion of the coating. Binding force analysis shows that both aluminum coatings are strongly adhered to the substrates.

  4. 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.

  5. 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.

  6. Repair, Evaluation, Maintenance, and Rehabilitation Research Program. State-of-the-Art Procedures for Sealing Coastal Structures with Grouts and Concretes (United States)


    sulfurous , boric, carbonic, and oxalic acid . Spe- cific salts include sodium bisulfate , sodium tetraborate, sodium bicarbonate, potassium-hydrogen oxalate...potassium bichromate, ferric chloride, sulfuric acid , aluminum sulfate (alum), aluminum chloride, ammonium persulfate, and copper sulfate. The bichromates... bisulfates , bicarbonates, sulfur dioxide, and sodium silico- fluoride. Sodium silicate also reacts with salts of some metals, such as 23 calcium

  7. Modeling dissolution in aluminum alloys (United States)

    Durbin, Tracie Lee


    Aluminum and its alloys are used in many aspects of modern life, from soda cans and household foil to the automobiles and aircraft in which we travel. Aluminum alloy systems are characterized by good workability that enables these alloys to be economically rolled, extruded, or forged into useful shapes. Mechanical properties such as strength are altered significantly with cold working, annealing, precipitation-hardening, and/or heat-treatments. Heat-treatable aluminum alloys contain one or more soluble constituents such as copper, lithium, magnesium, silicon and zinc that individually, or with other elements, can form phases that strengthen the alloy. Microstructure development is highly dependent on all of the processing steps the alloy experiences. Ultimately, the macroscopic properties of the alloy depend strongly on the microstructure. Therefore, a quantitative understanding of the microstructural changes that occur during thermal and mechanical processing is fundamental to predicting alloy properties. In particular, the microstructure becomes more homogeneous and secondary phases are dissolved during thermal treatments. Robust physical models for the kinetics of particle dissolution are necessary to predict the most efficient thermal treatment. A general dissolution model for multi-component alloys has been developed using the front-tracking method to study the dissolution of precipitates in an aluminum alloy matrix. This technique is applicable to any alloy system, provided thermodynamic and diffusion data are available. Treatment of the precipitate interface is explored using two techniques: the immersed-boundary method and a new technique, termed here the "sharp-interface" method. The sharp-interface technique is based on a variation of the ghost fluid method and eliminates the need for corrective source terms in the characteristic equations. In addition, the sharp-interface method is shown to predict the dissolution behavior of precipitates in aluminum

  8. 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...

  9. 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)....

  10. 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.


    The Safe Drinking Water Act states that no drinking water facility is reuqired to fluoridate their water, however, any facility fluoridating their water is bound by the Maximum contaminant Level (MCL) of 4 mg/L. A survey of 600 large water utilities was conducted in conjunction w...

  12. 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.

  13. Diffusion-bonded beryllium aluminum optical structures (United States)

    Grapes, Thomas F.


    Beryllium aluminum material can present significant advantages for optical support structures. A likely advantage of beryllium aluminum compared to aluminum or titanium for such structures is its higher specific stiffness. However, beryllium aluminum material is significantly more expensive than most competing materials. The cost problem with beryllium aluminum is exacerbated if fabrication methods that result in near net shape parts are not used. Near net shape methods result in the least amount of material "thrown away" in the fabrication process. Casting is a primary example of near net shape manufacturing that is appropriate for some optical support structures. Casting aluminum, and other materials as well, is common. Casting of beryllium aluminum is very difficult, however, and has not had significant success. Diffusion bonding - a different approach for achieving near net shape beryllium aluminum optical support structures, was pursued and accomplished. Diffusion bonding is a term used to describe the joining of solid metal pieces under high temperature and pressure, but without melting. Three different optical support structures were designed and built of beryllium aluminum using diffusion bonding. Relatively small solid beryllium aluminum pieces were arranged together and then joined under hot isostatic pressure conditions. The resulting relatively large pressure bonded part was then machined to achieve the final product. Significant cost savings as compared to machining the part from a solid block were realized. Difficulties achieving diffusion bonds in complex joints were experienced and addressed.

  14. Aluminum/air electrochemical cells


    Wang, Lei; 王雷


    Aluminum (Al) is a very promising energy carrier given its high capacity and energy density, low cost, earth abundance and environmental benignity. The Al/air battery as a kind of metal/air electrochemical cell attracts tremendous attention. Traditional Al/air batteries suffer from the self-corrosion and related safety problems. In this work, three new approaches were investigated to tackle these challenges and to develop high-performance Al/air cells: (1) incorporate an additional hydrogen/a...

  15. Electrically Conductive Anodized Aluminum Surfaces (United States)

    Nguyen, Trung Hung


    Anodized aluminum components can be treated to make them sufficiently electrically conductive to suppress discharges of static electricity. The treatment was conceived as a means of preventing static electric discharges on exterior satin-anodized aluminum (SAA) surfaces of spacecraft without adversely affecting the thermal-control/optical properties of the SAA and without need to apply electrically conductive paints, which eventually peel off in the harsh environment of outer space. The treatment can also be used to impart electrical conductivity to anodized housings of computers, medical electronic instruments, telephoneexchange equipment, and other terrestrial electronic equipment vulnerable to electrostatic discharge. The electrical resistivity of a typical anodized aluminum surface layer lies between 10(exp 11) and 10(exp 13) Omega-cm. To suppress electrostatic discharge, it is necessary to reduce the electrical resistivity significantly - preferably to anodized surface becomes covered and the pores in the surface filled with a transparent, electrically conductive metal oxide nanocomposite. Filling the pores with the nanocomposite reduces the transverse electrical resistivity and, in the original intended outer-space application, the exterior covering portion of the nanocomposite would afford the requisite electrical contact with the outer-space plasma. The electrical resistivity of the nanocomposite can be tailored to a value between 10(exp 7) and 10(exp 12) Omega-cm. Unlike electrically conductive paint, the nanocomposite becomes an integral part of the anodized aluminum substrate, without need for adhesive bonding material and without risk of subsequent peeling. The electrodeposition process is compatible with commercial anodizing production lines. At present, the electronics industry uses expensive, exotic, electrostaticdischarge- suppressing finishes: examples include silver impregnated anodized, black electroless nickel, black chrome, and black copper. In

  16. 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.

  17. Purification technology of molten aluminum

    Institute of Scientific and Technical Information of China (English)

    孙宝德; 丁文江; 疏达; 周尧和


    Various purification methods were explored to eliminate the dissolved hydrogen and nonmetallic inclusions from molten aluminum alloys. A novel rotating impeller head with self-oscillation nozzles or an electromagnetic valve in the gas circuit was used to produce pulse gas currents for the rotary impeller degassing method. Water simulation results show that the size of gas bubbles can be decreased by 10%-20% as compared with the constant gas current mode. By coating ceramic filters or particles with active flux or enamels, composite filters were used to filter the scrap A356 alloy and pure aluminum. Experimental results demonstrate that better filtration efficiency and operation performance can be obtained. Based on numerical calculations, the separation efficiency of inclusions by high frequency magnetic field can be significantly improved by using a hollow cylinder-like separator or utilizing the effects of secondary flow of the melt in a square separator. A multi-stage and multi-media purification platform based on these methods was designed and applied in on-line processing of molten aluminum alloys. Mechanical properties of the processed scrap A356 alloy are greatly improved by the composite purification.

  18. 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

  19. 78 FR 37973 - Change of Address for Region 7; Technical Correction (United States)


    ... procedure, Air pollution control, Aluminum, Ammonium sulfate plants, Batteries, Beverages, Carbon monoxide... disposal, Zinc. 40 CFR Part 61 Environmental protection, Air pollution control, Arsenic, Asbestos, Benzene... INFORMATION CONTACT: Jan Simpson, Environmental Protection Agency, Air Planning and Development Branch,...

  20. 40 CFR 180.920 - Inert ingredients used pre-harvest; exemptions from the requirement of a tolerance. (United States)


    ... Surfactants, related adjuvants of surfactants Aluminum sulfate Safener adjuvant Ammonium chloride (CAS Reg. No... weight (w/w) of pesticide formulations Deodorant, melting point adjustment Carbon Black (CAS Reg....

  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.


    Directory of Open Access Journals (Sweden)

    Josip Peko


    Full Text Available This study examined steel and aluminum variants of modern exhibition structures in which the main design requirements include low weight (increased span/depth ratio, transportation, and construction and durability (resistance to corrosion. This included a design situation in which the structural application of aluminum alloys provided an extremely convenient and practical solution. Viability of an aluminum structure depends on several factors and requires a detailed analysis. The overall conclusion of the study indicated that aluminum can be used as a structural material and as a viable alternative to steel for Croatian snow and wind load values and evidently in cases in which positive properties of aluminum are required for structural design. Furthermore, a structural fire analysis was conducted for an aluminum variant structure by using a zone model for realistic fire analysis. The results suggested that passive fire protection for the main structural members was not required in the event of areal fire with duration of 60 min.

  18. [Link between aluminum neurotoxicity and neurodegenerative disorders]. (United States)

    Kawahara, Masahiro


    Aluminum is an old element that has been known for a long time, but some of its properties are only now being discovered. Although environmentally abundant, aluminum is not essential for life; in fact, because of its specific chemical properties, aluminum inhibits more than 200 biologically important functions and exerts various adverse effects in plants, animals, and humans. Aluminum is a widely recognized neurotoxin. It has been suggested that there is a relationship between exposure to aluminum and neurodegenerative diseases, including dialysis encephalopathy, amyotrophic lateral sclerosis and parkinsonism dementia in the Kii Peninsula and Guam, as well as Alzheimer' s disease: however, this claim remains to be verified. In this chapter, we review the detailed characteristics of aluminum neurotoxicity and the link between Alzheimer' s disease and other neurodegenerative diseases, based on recent findings on metal-metal interactions and the functions of metalloproteins in synapses.

  19. Optical Transmittance of Anodically Oxidized Aluminum Alloy (United States)

    Saito, Mitsunori; Shiga, Yasunori; Miyagi, Mitsunobu; Wada, Kenji; Ono, Sachiko


    Optical transmittance and anisotropy of anodic oxide films that were made from pure aluminum and an aluminum alloy (A5052) were studied. The alloy oxide film exhibits an enhanced polarization function, particularly when anodization is carried out at a large current density. It was revealed by chemical analysis that the alloy oxide film contains a larger amount of unoxidized aluminum than the pure-aluminum oxide film. The polarization function can be elucidated by considering unoxidized aluminum particles that are arranged in the columnar structure of the alumina film. Electron microscope observation showed that many holes exist in the alloy oxide film, around which columnar cells are arranged irregularly. Such holes and irregular cell arrangement cause the increase in the amount of unoxidized aluminum, and consequently induces scattering loss.

  20. Structure of Liquid Aluminum and Hydrogen Absorption

    Institute of Scientific and Technical Information of China (English)

    LIU Yang; DAI Yongbing; WANG Jun; SHU Da; SUN Baode


    The hydrogen content in aluminum melts at different temperature was detected. The structure in aluminum melts was investigated by molecular dynamics simulation. The first peak position of pair correlation function, atomic coordination number and viscosity of aluminum melts were calculated and they changed abnormally in the same temperature range. The mechanism of hydrogen absorption has been discussed. From molecular dynamics calculations, the interdependence between melt structural properties and hydrogen absorption were obtained.

  1. Improved virus removal by high-basicity polyaluminum coagulants compared to commercially available aluminum-based coagulants. (United States)

    Shirasaki, N; Matsushita, T; Matsui, Y; Oshiba, A; Marubayashi, T; Sato, S


    We investigated the effects of basicity, sulfate content, and aluminum hydrolyte species on the ability of polyaluminum chloride (PACl) coagulants to remove F-specific RNA bacteriophages from river water at a pH range of 6-8. An increase in PACl basicity from 1.5 to 2.1 and the absence of sulfate led to a reduction of the amount of monomeric aluminum species (i.e., an increase of the total amount of polymeric aluminum and colloidal aluminum species) in the PACl, to an increase in the colloid charge density of the PACl, or to both and, as a result, to high virus removal efficiency. The efficiency of virus removal at around pH 8 observed with PACl-2.1c, a nonsulfated high-basicity PACl (basicity 2.1-2.2) with a high colloidal aluminum content, was larger than that observed with PACl-2.1b, a nonsulfated high-basicity PACl (basicity 2.1-2.2) with a high polymeric aluminum content. In contrast, although extremely high basicity PACls (e.g., PACl-2.7ns, basicity 2.7) effectively removed turbidity and UV260-absorbing natural organic matter and resulted in a very low residual aluminum concentration, the virus removal ratio with PACl-2.7ns was smaller than the ratio with PACl-2.1c at around pH 8, possibly as a result of a reduction of the colloid charge density of the PACl as the basicity was increased from 2.1 to 2.7. Liquid (27)Al NMR analysis revealed that PACl-2.1c contained Al30 species, which was not the case for PACl-2.1b or PACl-2.7ns. This result suggests that Al30 species probably played a major role in virus removal during the coagulation process. In summary, PACl-2.1c, which has high colloidal aluminum content, contains Al30 species, and has a high colloid charge density, removed viruses more efficiently (>4 log10 for infectious viruses) than the other aluminum-based coagulants-including commercially available PACls (basicity 1.5-1.8), alum, and PACl-2.7ns-over the entire tested pH (6-8) and coagulant dosage (0.54-5.4 mg-Al/L) ranges.

  2. 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

  3. Aluminum-stabilized NB3SN superconductor (United States)

    Scanlan, Ronald M.


    An aluminum-stabilized Nb.sub.3 Sn superconductor and process for producing same, utilizing ultrapure aluminum. Ductile components are co-drawn with aluminum to produce a conductor suitable for winding magnets. After winding, the conductor is heated to convert it to the brittle Nb.sub.3 Sn superconductor phase, using a temperature high enough to perform the transformation but still below the melting point of the aluminum. This results in reaction of substantially all of the niobium, while providing stabilization and react-in-place features which are beneficial in the fabrication of magnets utilizing superconducting materials.

  4. 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.

  5. [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.

  6. 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.

  7. 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.

  8. Silicon reduces aluminum accumulation in rats: relevance to the aluminum hypothesis of Alzheimer disease. (United States)

    Bellés, M; Sánchez, D J; Gómez, M; Corbella, J; Domingo, J L


    In recent years, a possible relation between the aluminum and silicon levels in drinking water and the risk of Alzheimer disease (AD) has been established. It has been suggested that silicon may have a protective effect in limiting oral aluminum absorption. The present study was undertaken to examine the influence of supplementing silicon in the diet to prevent tissue aluminum retention in rats exposed to oral aluminum. Three groups of adult male rats were given by gavage 450 mg/kg/day of aluminum nitrate nonahydrate 5 days a week for 5 weeks. Concurrently, animals received silicon in the drinking water at 0 (positive control), 59, and 118 mg Si/L. A fourth group (-Al, - Si) was designated as a negative control group. At the end of the period of aluminum and silicon administration, urines were collected for 4 consecutive days, and the urinary aluminum levels were determined. The aluminum concentrations in the brain (various regions), liver, bone, spleen, and kidney were also measured. For all tissues, aluminum levels were significantly lower in the groups exposed to 59 and 118 mg Si/L than in the positive control group; significant reductions in the urinary aluminum levels of the same groups were also found. The current results corroborate that silicon effectively prevents gastrointestinal aluminum absorption, which may be of concern in protecting against the neurotoxic effects of aluminum.

  9. The Aluminum Deep Processing Project of North United Aluminum Landed in Qijiang

    Institute of Scientific and Technical Information of China (English)


    <正>On April 10,North United Aluminum Company respectively signed investment cooperation agreements with Qijiang Industrial Park and Qineng Electricity&Aluminum Co.,Ltd,signifying the landing of North United Aluminum’s aluminum deep processing project in Qijiang.

  10. 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.

  11. 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...

  12. 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...

  13. 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.

  15. 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...

  16. 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.

  17. 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.

  18. 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.

  19. 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

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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...

  8. Laboratory Powder Metallurgy Makes Tough Aluminum Sheet (United States)

    Royster, D. M.; Thomas, J. R.; Singleton, O. R.


    Aluminum alloy sheet exhibits high tensile and Kahn tear strengths. Rapid solidification of aluminum alloys in powder form and subsequent consolidation and fabrication processes used to tailor parts made of these alloys to satisfy such specific aerospace design requirements as high strength and toughness.

  9. Sanmenxia strives to create aluminum industrial base

    Institute of Scientific and Technical Information of China (English)


    <正>Contradiction between rich alumina resource and relatively weak electrolytic aluminum production capacity is the "bottleneck" inhibiting development of aluminum industry in San-menxia. During the period of "11th Five-Year Development", Sanmenxia will relay on its

  10. Wilson's disease; increased aluminum in liver. (United States)

    Yasui, M; Yoshimasu, F; Yase, Y; Uebayashi, Y


    Interaction of trace metal metabolism was studied in a patient with Wilson's dease. Atomic absorption analysis showed markedly increased urinary excretion of copper and aluminum and an increased aluminum content was found in the biopsied liver by neutron activation analysis. These findings suggest a complicated pathogenetic mechanism involving other metals besides copper in the Wilson's disease.

  11. Recrystallization in Commercially Pure Aluminum

    DEFF Research Database (Denmark)

    Bay, Bent; Hansen, Niels


    Recrystallization behavior in commercial aluminum with a purity of 99.4 pct was studied by techniques such as high voltage electron microscopy, 100 kV transmission electron microscopy, and light microscopy. Sample parameters were the initial grain size (290 and 24 microns) and the degree of defor......Recrystallization behavior in commercial aluminum with a purity of 99.4 pct was studied by techniques such as high voltage electron microscopy, 100 kV transmission electron microscopy, and light microscopy. Sample parameters were the initial grain size (290 and 24 microns) and the degree...... (FeAl3), which start to become operative when the degree of deformation is raised from 15 to 30 pct. The temperature of nucleation and of recrystallization decreases when the degree of deformation is increased and the initial grain size is decreased. The recrystallized grain size follows the same...... trend and it is observed that the refinement of the recrystallized grain size caused by an increasing degree of deformation and decreasing initial grain size is enhanced by the FeAl3 particles (when the degree of deformation is raised from 15 to 30 pct). Finally, the structural and kinetic observations...

  12. Aluminum honeycomb impact limiter study

    Energy Technology Data Exchange (ETDEWEB)

    Yaksh, M.C.; Thompson, T.C. (Nuclear Assurance Corp., Norcross, GA (United States)); Nickell, R.E. (Applied Science and Technology, Inc., Poway, CA (United States))


    Design requirements for a cask transporting radioactive materials must include the condition of the 30-foot free fall of the cask onto an unyielding surface. To reduce the deceleration loads to a tolerable level for all the components of the cask, a component (impact limiter) is designed to absorb the kinetic energy. The material, shape, and method of attachment of the impact limiter to the cask body comprises the design of the impact limiter. The impact limiter material of interest is honeycomb aluminum, and the particular design examined was for the NAC Legal Weight Truck cask (NAC-LWT) for spent fuel from light water reactors. The NAC-LWT has a design weight of 52,000 pounds, and it has a nominal length of 200 inches. The report describes the numerical calculations embodied in the FADE program to determine the accelerations and crush strain resulting from an arbitrary height and angle of orientation. Since the program serves as a design tool, static tests are performed to assess the effect of the shell containing the honeycomb aluminum. The static tests and their results are contained in the study. The static tests are used to demonstrate for licensing purposes the level of accelerations imposed on the cask during a 30-foot drop. 3 refs., 41 figs., 15 tabs.

  13. Aluminum corrosion product release kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, Matt, E-mail:; Semmler, Jaleh; Guzonas, Dave; Chen, Hui Qun; Toor, Arshad; Hoendermis, Seanna


    Highlights: • Release of Al corrosion product was measured in simulated post-LOCA sump solutions. • Increased boron was found to enhance Al release kinetics at similar pH. • Models of Al release as functions of time, temperature, and pH were developed. - Abstract: The kinetics of aluminum corrosion product release was examined in solutions representative of post-LOCA sump water for both pressurized water and pressurized heavy-water reactors. Coupons of AA 6061 T6 were exposed to solutions in the pH 7–11 range at 40, 60, 90 and 130 °C. Solution samples were analyzed by inductively coupled plasma atomic emission spectroscopy, and coupon samples were analyzed by secondary ion mass spectrometry. The results show a distinct “boron effect” on the release kinetics, expected to be caused by an increase in the solubility of the aluminum corrosion products. New models were developed to describe both sets of data as functions of temperature, time, and pH (where applicable)

  14. 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.

  15. 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.

  16. 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...

  17. 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.

  18. 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.

  19. 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

  20. 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

  1. 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.

  2. 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.

  3. 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

  4. Gating of Permanent Molds for ALuminum Casting

    Energy Technology Data Exchange (ETDEWEB)

    David Schwam; John F. Wallace; Tom Engle; Qingming Chang


    This report summarizes a two-year project, DE-FC07-01ID13983 that concerns the gating of aluminum castings in permanent molds. The main goal of the project is to improve the quality of aluminum castings produced in permanent molds. The approach taken was determine how the vertical type gating systems used for permanent mold castings can be designed to fill the mold cavity with a minimum of damage to the quality of the resulting casting. It is evident that somewhat different systems are preferred for different shapes and sizes of aluminum castings. The main problems caused by improper gating are entrained aluminum oxide films and entrapped gas. The project highlights the characteristic features of gating systems used in permanent mold aluminum foundries and recommends gating procedures designed to avoid common defects. The study also provides direct evidence on the filling pattern and heat flow behavior in permanent mold castings.

  5. Gelling nature of aluminum soaps in oils. (United States)

    Wang, Xiaorong; Rackaitis, Mindaugas


    Aluminum soaps are notable for their ability to form soap-hydrocarbon gels of high viscosity. For more than half a century, it has been believed that the gelling mechanism is due to a formation of polymeric chains of aluminum molecules with the aluminum atoms linking along the axis and with the fatty acid chain extended sideways. Here we report results from an investigation using high-resolution electron microscopy and rheology measurements that clearly resolve the ambiguity. Our results reveal that the gelling mechanism stems from the formation of spherical nano-sized micelles from aluminum soap molecules, and those colloidal micelle particles then aggregate into networks of highly fractal and jammed structures. The earlier proposed polymer chain-like structure is definitely incorrect. The discovery of aluminum soap particles could expand application of these materials to new technologies.

  6. Aluminum-based metal-air batteries

    Energy Technology Data Exchange (ETDEWEB)

    Friesen, Cody A.; Martinez, Jose Antonio Bautista


    Provided in one embodiment is an electrochemical cell, comprising: (i) a plurality of electrodes, comprising a fuel electrode that comprises aluminum and an air electrode that absorbs gaseous oxygen, the electrodes being operable in a discharge mode wherein the aluminum is oxidized at the fuel electrode and oxygen is reduced at the air electrode, and (ii) an ionically conductive medium, comprising an organic solvent; wherein during non-use of the cell, the organic solvent promotes formation of a protective interface between the aluminum of the fuel electrode and the ionically conductive medium, and wherein at an onset of the discharge mode, at least some of the protective interface is removed from the aluminum to thereafter permit oxidation of the aluminum during the discharge mode.

  7. Proposal of recycling system for waste aluminum

    Directory of Open Access Journals (Sweden)

    Š. Valenčík


    Full Text Available Introduced work is focused on waste aluminum recycling process with objective to propose complex production system for recovering of aluminum and some aluminum alloys. Solution is supported by extended analysis concerning purpose, basis and system sequences for recyclation. Based on that, sources, possibilities and conditions for recycling are formed. This has been used in proposal of manufacturing system. The principle is the structural proposal of manufacturing system, which does not only differentiate the stage of aluminum melting process, but also related stages as gross separation, sizing, containerisation and batching, palletisation, stacking and some related operations. Production system respects technological specifications, requirements for rationalisation of manufacturing systems, technical and economical feasibility conditions and is considered in lower automation level. However production system solves complex problem of recycling of some types of aluminum, it improves flexibility, production, quality (melting by high enforcements and in protective atmosphere and extention of production (final products production.

  8. Trends in the global aluminum fabrication industry (United States)

    Das, Subodh; Yin, Weimin


    The aluminum fabrication industry has become more vital to the global economy as international aluminum consumption has grown steadily in the past decades. Using innovation, value, and sustainability, the aluminum industry is strengthening its position not only in traditional packaging and construction applications but also in the automotive and aerospace markets to become more competitive and to face challenges from other industries and higher industrial standards. The aluminum fabrication industry has experienced a significant geographical shift caused by rapid growth in emerging markets in countries such as Brazil, Russia, India, and China. Market growth and distribution will vary with different patterns of geography and social development; the aluminum industry must be part of the transformation and keep pace with market developments to benefit.

  9. 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.

  10. Aluminum phosphate shows more adjuvanticity than Aluminum hydroxide in recombinant hepatitis –B vaccine formulation

    Directory of Open Access Journals (Sweden)


    Full Text Available Background: Although a number of investigation have been carried out to find alternative adjuvants to aluminum salts in vaccine formulations, they are still extensively used due to their good track record of safety, low cost and proper adjuvanticity with a variety of antigens. Adsorption of antigens onto aluminum compounds depends heavily on electrostatic forces between adjuvant and antigen. Commercial recombinant protein hepatitis B vaccines containing aluminum hydroxide as adjuvant is facing low induction of immunity in some sections of the vaccinated population. To follow the current global efforts in finding more potent hepatitis B vaccine formulation, adjuvanticity of aluminum phosphate has been compared to aluminum hydroxide. Materials and methods: The adjuvant properties of aluminum hydroxide and aluminum phosphate in a vaccine formulation containing a locally manufactured hepatitis B (HBs surface antigen was evaluated in Balb/C mice. The formulations were administered intra peritoneally (i.p. and the titers of antibody which was induced after 28 days were determined using ELISA technique. The geometric mean of antibody titer (GMT, seroconversion and seroprotection rates, ED50 and relative potency of different formulations were determined. Results: All the adjuvanicity markers obtained in aluminum phosphate formulation were significantly higher than aluminum hydroxide. The geometric mean of antibody titer of aluminum phosphate was approximately three folds more than aluminum hydroxide. Conclusion: Aluminum phosphate showed more adjuvanticity than aluminum hydroxide in hepatitis B vaccine. Therefore the use of aluminum phosphate as adjuvant in this vaccine may lead to higher immunity with longer duration of effects in vaccinated groups.

  11. 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...

  12. 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.

  13. Characterization of aluminum surfaces: Sorption and etching (United States)

    Polkinghorne, Jeannette Clera

    Aluminum, due to its low density and low cost, is a key material for future lightweight applications. However, like other structural materials, aluminum is subject to various forms of corrosion damage that annually costs the United States approximately 5% of its GNP [1]. The main goal is to investigate the effects of various solution anions on aluminum surfaces, and specifically probe pit initiation and inhibition. Using surface analysis techniques including X-ray photoelectron spectroscopy, Auger electron spectroscopy, and scanning electron microscopy, results have been correlated with those obtained from electrochemical methods and a radiolabeling technique developed in the Wieckowski laboratory. Analysis of data has indicated that important variables include type of anion, solution pH, and applied electrode potential. While aggressive anions such as chloride are usually studied to elucidate corrosion processes to work ultimately toward inhibition, its corrosive properties can be successfully utilized in the drive for higher energy and smaller-scale storage devices. Fundamental information gained regarding anion interaction with the aluminum surface can be applied to tailor etch processes. Standard electrochemical techniques and SEM are respectively used to etch and analyze the aluminum substrate. Aluminum electrolytic capacitors are comprised of aluminum anode foil covered by an anodically grown aluminum oxide dielectric film, electrolytic paper impregnated with electrolyte, and aluminum cathode foil. Two main processes are involved in the fabrication of aluminum electrolytic capacitors, namely etching and anodic oxide formation. Etching of the anode foil results in a higher surface area (up to 20 times area enlargement compared to unetched foil) that translates into a higher capacitance gain, permitting more compact and lighter capacitor manufacture. Anodic oxide formation on the anode, creates the required dielectric to withstand high voltage operation. A

  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. 氨水沉淀法由含钛滤液提取二氧化钛%Recovery of titanium dioxide from titanium-bearing solution by using ammonium as precipitant

    Institute of Scientific and Technical Information of China (English)

    张悦; 王思佳; 薛向欣


    以含钛高炉渣为原料,经硫酸铵熔融法得到含钛滤液,然后以氨水为沉淀剂,控制pH值使钛水解,水解产物经600℃煅烧2h得到二氧化钛.考察了螫合剂的加入量、溶液pH值和反应时间对钛沉淀率的影响,实验结果表明:反应过程中铁与钛发生共沉淀,造成二氧化钛产物中的铁含量过高.EDTA几乎完全抑制了铁的沉淀,明显降低了二氧化钛产物的全铁含量;2-羟基丙烷-1,2,3-三羧酸的加入降低了产物中二氧化硅的含量,提高了产物中二氧化钛的含量.当2-羟基丙烷-1,2,3-三羧酸与硅的摩尔比为1,EDTA与铁的摩尔比为3,pH值为2.0,反应时间为90 min时产物中二氧化钛的含量为96.35%.%Extraction of titanium dioxide from titanium-bearing blast furnace slag was studied. Firstly, the titanium-bearing blast furnace slag reacted with ammonium sulfate to obtain NH3 and TiOSO4 solution, and then titanium dioxide was precipitated from TiOSO4 solution by using ammonium as precipitant. Finally, the filtered precipitate was calcined in a muffle furnace at 600℃ for 2 h. The effects of quantities of chelate reagent added, pH and holding time on the precipitation rate of titanium were investigated. The results showed that the precipitation rate of titanium, aluminum and iron increased with increasing solution pH since NH3 was used as precipitant and during this stage iron ion hydrolyzed to form Fe(OH)3. The hydrolysis of Fe3+ was restrained by EDTA addition into the solution. At the same time, the content of iron in production decreased and the content of TiO2 increased. The precipitation of silicon was restrained by citric acid (a novel additive) addition into the solution. At the same time, the content of silicon dioxide in production decreased and the content of TiO2 increased. The TiO2 content of the production increased with increasing EDTA/Fe3+ molar ratio. TiO2 with purity 96. 35% was obtained when EDTA/Fe3+ molar ratio increased to 3