Sample records for ammonium bicarbonate buffer

  1. 21 CFR 184.1135 - Ammonium bicarbonate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...bicarbonate (NH4 HCO3 , CAS Reg. No. 1066-33-7) is prepared by reacting gaseous carbon dioxide with aqueous ammonia. Crystals of ammonium bicarbonate are precipitated from solution and subsequently washed and dried. (b) The ingredient...

  2. Supporting Information for: Ammonium Bicarbonate Transport in Anion Exchange Membranes

    E-print Network

    S1 Supporting Information for: Ammonium Bicarbonate Transport in Anion Exchange Membranes was measured by first equilibrating the polymer film in the desired solution [e.g., DI water, 0.5 mol/L sodium chloride (NaCl), or 0.5 mol/L ammonium bicarbonate (AmB)]. Films were allowed to equilibrate

  3. Sodium bicarbonate and Alkaten as buffers in beef cattle diets

    E-print Network

    Boerner, Benedict Joseph

    1985-01-01

    SODIUM BICARBONATE AND ALKATEN AS BUFFERS IN BEEF CATTLE DIETS A Thesis by BENED ICT JOSEP H BOERNER Submitted to the Graduate College of Texas A8M University im partial fulfillment of the requirements for the degree of MASTER OF SC IENCE... August 1985 Major Subject: Nutrition SODIUM BICARBONATE AND ALKATEN AS BUFFERS IN BEEF CATTLE DIETS A thesis by BENEDICT JOSEPH BOERNER Approved as to style and content by: Flo M. Byers (Chairma of Committee) ~r( Gerald T. Schelling (Member...

  4. Long-Term Ammonium Chloride or Sodium Bicarbonate Treatment in Two Models of Polycystic Kidney Disease

    Microsoft Academic Search

    Vicente E. Torres; Michael G. Branden; Izumi Yoshida; Vincent H. Gattone

    2001-01-01

    Administration of ammonium chloride aggravates, while short-term administration of sodium or potassium bicarbonate lessens the development of polycystic kidney disease in Han:SPRD rats. We have conducted studies to determine whether the protection afforded by the administration of sodium bicarbonate is sustained and prevents development of uremia during chronic administration and whether the effects of the administration of ammonium chloride and

  5. Effects of ammonium bicarbonate on the electrospray mass spectra of proteins: evidence for bubble-induced unfolding.

    PubMed

    Hedges, Jason B; Vahidi, Siavash; Yue, Xuanfeng; Konermann, Lars

    2013-07-01

    Many protein investigations by electrospray ionization (ESI) mass spectrometry (MS) strive to ensure a "native" solvent environment, i.e., nondenaturing conditions up to the point of gas-phase ion formation. Ideally, these studies would employ a volatile pH buffer to mitigate changes in H(+) concentration that can occur during ESI. Ammonium acetate is a commonly used additive, despite its low buffering capacity at pH 7. Ammonium bicarbonate provides greatly improved pH stabilization, thus offering an interesting alternative. Surprisingly, protein analyses in bicarbonate at pH 7 tend to result in the formation of very high charge states, similar to those obtained when electrospraying unfolded proteins in a denaturing solvent. This effect has been reported previously (Sterling, H. J.; Cassou, C. A.; Susa, A. C.; Williams, E. R. Anal. Chem. 2012, 84, 3795), but its exact mechanistic origin remains unclear. ESI-mediated unfolding does not take place in acetate under otherwise identical conditions. We demonstrate that heating of protein-containing bicarbonate solutions results in extensive foaming, caused by CO2 outgassing. In contrast, acetate solutions do not generate foam. Protein denaturation caused by gas bubbles is a well-known phenomenon. Adsorption to the gas/liquid interface is accompanied by major conformational changes that allow the protein to act as a surfactant. The foaming of beer is a manifestation of this effect. Bubble formation in bicarbonate during ESI is facilitated by collisional and blackbody droplet heating. Our data imply that heat and bubbles act synergistically to cause unfolding during the electrospray process, while proteins reside in ESI droplets. Because of this effect we advise against the use of ammonium bicarbonate for native ESI-MS. Ammonium acetate represents a gentler droplet environment, despite its low buffering capacity. PMID:23724896

  6. Highly Efficient Hydrogen Storage System Based on Ammonium Bicarbonate/Formate Redox Equilibrium over Palladium Nanocatalysts.

    PubMed

    Su, Ji; Yang, Lisha; Lu, Mi; Lin, Hongfei

    2015-03-01

    A highly efficient, reversible hydrogen storage-evolution process has been developed based on the ammonium bicarbonate/formate redox equilibrium over the same carbon-supported palladium nanocatalyst. This heterogeneously catalyzed hydrogen storage system is comparable to the counterpart homogeneous systems and has shown fast reaction kinetics of both the hydrogenation of ammonium bicarbonate and the dehydrogenation of ammonium formate under mild operating conditions. By adjusting temperature and pressure, the extent of hydrogen storage and evolution can be well controlled in the same catalytic system. Moreover, the hydrogen storage system based on aqueous-phase ammonium formate is advantageous owing to its high volumetric energy density. PMID:25663262

  7. The influence of carbon dioxide, bicarbonate and other buffers on the potential of antimony microelectrodes

    Microsoft Academic Search

    P. Quehenberger; S. David

    1977-01-01

    Summary Antimony microelectrodes were calibrated at 37° C in phosphate buffers, in different bicarbonate solutions at various CO2-partial pressures and in buffers like TRIS, TES, MES and malonic acid. By use of the latter buffers (with exception of malonic acid) the most reliable calibration curves were obtained (“normal values”). The usual calibration in 67 mmol\\/l standard phosphate buffers turned out

  8. Physiological bicarbonate buffers: stabilisation and use as dissolution media for modified release systems.

    PubMed

    Fadda, Hala M; Merchant, Hamid A; Arafat, Basel T; Basit, Abdul W

    2009-12-01

    Bicarbonate media are reflective of the ionic composition and buffer capacity of small intestinal luminal fluids. Here we investigate methods to stabilise bicarbonate buffers which can be readily applied to USP-II dissolution apparatus. The in vitro drug release behaviour of three enteric coated mesalazine (mesalamine) products is investigated. Asacol 400 mg and Asacol 800 mg (Asacol HD) and the new generation, high dose (1200 mg) delayed and sustained release formulation, Mezavant (Lialda), are compared in pH 7.4 Krebs bicarbonate and phosphate buffers. Bicarbonate stabilisation was achieved by: continuous sparging of the medium with 5% CO(2)(g), application of a layer of liquid paraffin above the medium, or a specially designed in-house seal device that prevents CO(2)(g) loss. Each of the products displayed a delayed onset of drug release in physiological bicarbonate media compared to phosphate buffer. Moreover, Mezavant displayed a zero-order, sustained release profile in phosphate buffer; in bicarbonate media, however, this slow drug release was no longer apparent and a profile similar to that of Asacol 400 mg was observed. These similar release patterns of Asacol 400 mg and Mezavant displayed in bicarbonate media are in agreement with their pharmacokinetic profiles in humans. Bicarbonate media provide a better prediction of the in vivo behaviour of the mesalazine preparations investigated. PMID:19666093

  9. ELECTROANTENNOGRAM RESPONSE OF ANASTREPHA SUSPENSA (DIPTERA: TEPHRITIDAE) TO AMMONIUM BICARBONATE AND PUTRESCINE LURES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Current trapping systems for Anastrepha fruit flies utilize a two-component attractant consisting of ammonium bicarbonate and putrescine. Though ammonia-based lures have been highly effective for some tephritids (e.g. Mediterranean fruit fly, Ceratitis capitata), attraction of Anastrepha species has...

  10. Simultaneous desulfurization and denitrification by microwave reactor with ammonium bicarbonate and zeolite.

    PubMed

    Wei, Zaishan; Lin, Zhehang; Niu, Hejingying; He, Haiming; Ji, Yongfeng

    2009-03-15

    Microwave reactor with ammonium bicarbonate (NH(4)HCO(3)) and zeolite was set up to study the simultaneous removal of sulfur dioxide (SO(2)) and nitrogen oxides (NO(x)) from flue gas. The results showed that the microwave reactor filled with NH(4)HCO(3) and zeolite could reduce SO(2) to sulfur with the best desulfurization efficiency of 99.1% and reduce NO(x) to nitrogen with the best NO(x) purifying efficiency of 86.5%. Microwave desulfurization and denitrification effect of the experiment using ammonium bicarbonate and zeolite together is much higher than that using ammonium bicarbonate or zeolite only. NO(x) concentration has little effect on denitrification but has no influence on desulfurization, SO(2) concentration has no effect on denitrification. The optimal microwave power and empty bed residence time (EBRT) on simultaneous desulfurization and dentrification are 211-280 W and 0.315 s, respectively. The mechanism for microwave reduced desulfurization and denitrification can be described as the microwave-induced catalytic reduction reaction between SO(2), NO(x) and ammonium bicarbonate with zeolite being the catalyst and microwave absorbent. PMID:18617325

  11. Ammonium Bicarbonate Transport in Anion Exchange Membranes for Salinity Gradient Energy

    E-print Network

    Ammonium Bicarbonate Transport in Anion Exchange Membranes for Salinity Gradient Energy Geoffrey M 16802, United States *S Supporting Information ABSTRACT: Many salinity gradient energy technologies recovery using AmB thermolytic solutions in RED. Recent interest in salinity gradient energy technologies

  12. Bicarbonate/lactate- and bicarbonate-buffered peritoneal dialysis fluids improve ex vivo peritoneal macrophage TNFalpha secretion.

    PubMed

    MacKenzie, R K; Holmes, C J; Moseley, A; Jenkins, J P; Williams, J D; Coles, G A; Faict, D; Topley, N

    1998-08-01

    Peritoneal macrophage (PMO) function was examined ex vivo after their in vivo exposure to either acidic, lactate-buffered solutions (PD4; 40 mM lactate, pH 5.2), bicarbonate/lactate-buffered solution (TBL; 25 mM/15 mM bicarbonate/lactate, pH 7.3), or bicarbonate-buffered solution (TB; 38 mM bicarbonate, pH 7.3), containing either 1.36 or 3.86% glucose. Initial experiments demonstrated that tumor necrosis factor-alpha (TNFalpha) release (assessed by TNF-direct immunoassay [DIA]) from PMO isolated from the peritoneal cavities of patients exposed to conventional fluid (PD4 1.36% glucose) was lowest after 30 min of intraperitoneal dwell (3591+/-1200 versus 28,946+/-9359 for 240-min dwell [pg/ml], n=5, P < 0.05). Five patients were exposed on 3 successive days to PD4, TBL, and TB for 30-min acute dwells containing 1.36% glucose in the first week and 3.86% glucose during the second. PMO TNFalpha release was assessed after ex vitro exposure to lipopolysaccharide (LPS). Exposure of PMO to TBL or TB (1.36% glucose) resulted in a significant increase in the generation of TNFalpha (pg/2 X 10(6) PMO) compared with PD4. TBL: 68,659+/-35,633, TB: 53,682+/-26,536 versus PD4 17,107+/-8996 (LPS 1.0 ng/ml, n=5 patients, P=0.043 versus PD4 for both). PMO that were recovered from PD4 and TB dwells (3.86% glucose) showed no significant difference in TNFalpha secretion (21,661+/-6934 and 23,923+/-9147, respectively). In contrast, exposure to TBL resulted in a significant increase (41,846+/-11,471) compared with PD4 (LPS 1.0 ng/ml, n=5 patients, P=0.043). These data demonstrate enhanced PMO function after in vivo exposure to bicarbonate- and bicarbonate/lactate-buffered solutions. This response was sustained in TBL alone at the highest glucose concentrations. These results suggest that the newer solutions, and particularly bicarbonate/lactate, might improve host defense status in peritoneal dialysis patients. PMID:9697673

  13. In vivo exposure to bicarbonate/lactate- and bicarbonate-buffered peritoneal dialysis fluids improves ex vivo peritoneal macrophage function.

    PubMed

    Mackenzie, R K; Jones, S; Moseley, A; Holmes, C J; Argyle, R; Williams, J D; Coles, G A; Pu, K; Faict, D; Topley, N

    2000-01-01

    The impact on peritoneal macrophage (PMO) function of acidic lactate-buffered (Lac-PDF [PD4]; 40 mmol/L of lactate; pH 5.2) and neutral-pH, bicarbonate-buffered (TB; 38 mmol/L of bicarbonate; pH 7. 3) and bicarbonate/lactate-buffered (TBL; 25 mmol/L of bicarbonate/15 mmol/L of lactate; pH 7.3) peritoneal dialysis fluids (PDFs) was compared during a study of continuous therapy with PD4, TB, or TBL. During a run-in phase of 6 weeks when all patients (n = 15) were treated with their regular dialysis regimen with Lac-PDF, median PMO tumor necrosis factor alpha (TNFalpha) release values were 203.6, 89.9, and 115.5 pg TNFalpha/10(6) PMO in the patients subsequently randomized to the PD4, TB, and TBL treatment groups, respectively. Median stimulated TNFalpha values (serum-treated zymosan [STZ], 10 microgram/mL) were 1,894.6, 567.3, and 554.5 pg TNFalpha/10(6) PMO in the same groups, respectively. During the trial phase of 12 weeks, when the three groups of patients (n = 5 per group) were randomized to continuous treatment with PD4, TB, or TBL, median constitutive TNFalpha release values were 204.7, 131.4, and 155.4 pg TNFalpha/10(6) PMO, respectively. Stimulated TNFalpha values (STZ, 10 microgram/mL) were 1,911, 1,832, and 1,378 pg TNFalpha/10(6) PMO in the same groups, respectively. Repeated-measures analysis of variance comparing the run-in phase with the trial phase showed that PMO TNFalpha release was significantly elevated in patients treated with both TB (P = 0.040) and TBL (P = 0.014) but not in patients treated with Lac-PDF (P = 0. 795). These data suggest that patients continuously exposed to bicarbonate- and bicarbonate/lactate-buffered PDFs might have better preserved PMO function and thus improved host defense status. PMID:10620552

  14. Manganese-dependent disproportionation of hydrogen peroxide in bicarbonate buffer.

    PubMed Central

    Stadtman, E R; Berlett, B S; Chock, P B

    1990-01-01

    At physiological concentrations of HCO3- and CO2, Mn(II) catalyzes disproportionation of H2O2. This catalase-like activity is directly proportional to the concentrations of Mn(II) and H2O2, and it increases exponentially with increases in pH. The effect of increasing pH is almost completely attributable to the concomitant increase in HCO3- concentration. The rate is proportional to the third power of the HCO3- concentration, suggesting that 3 equivalents of HCO3- combine with 1 equivalent of Mn(II) to form the catalytic complex. It is presumed that the redox potential of the Mn(II) in equilibrium with Mn(III) couple in such a complex permits H2O2 to carry out facile reactions with Mn(II) comparable to those that occur with Fe(III) and Cu(II) chelate complexes, in which OH. and O2-. are established intermediates. The Mn-catalyzed disproportionation of H2O2 does not occur at physiological pH in the absence of HCO3-. Hepes, inorganic phosphate, and inorganic pyrophosphate inhibit the reaction catalyzed by the Mn/HCO3- system. These results are similar to those of Sychev et al. [Sychev, A.Y., Pfannmeller, U. & Isak, V.G. (1983) Russ. J. Phys. Chem. 57, 1690-1693]. The catalase-like activity of Mn(II)-bicarbonate complexes reported here, together with the superoxide dismutase activity of Mn complexes demonstrated by Archibald and Fridovich [Archibald, F.S. & Fridovich, I. (1982) Arch. Biochem. Biophys. 214, 452-463], strengthen the proposition that Mn may play an important role in the protection of cells against oxygen radical-mediated damage. PMID:2296593

  15. EFFECTS OF LIMESTONE AND SODIUM BICARBONATE BUFFERS ON RUMEN MEASUREMENTS AND RATE OF PASSAGE IN CATTLE

    Microsoft Academic Search

    G. L. Haaland; H. F. Tyrrell

    Summary Eight rumen-fistulated cattle (four Angus steers and four nonlactating Holstein cows) were fed a cracked corn-based concentrate (65% of dry matter) and corn silage (35% of dry matter) diet containing: (1) no buffer, (2) 2.5% limestone, (3) 2% sodium bicarbonate (NaHCO3) or (4) 1.25% limestone and 1.25% NaHCO3. Each diet was fed at approximately maintenance and-two times maintenance levels

  16. Work in progress report - Cardiopulmonary bypass Bicarbonate buffered ultrafiltration leads to a physiologic priming solution in pediatric cardiac surgery

    Microsoft Academic Search

    Wilhelm Alexander Osthaus; Jan Sievers; Thomas Breymann; Robert Suempelmann

    Pediatric cardiopulmonary bypass (CPB) involves a high ratio of priming blood volume to patient blood volume. The composition of packed red blood cells (RBCs) is very unphysiological in terms of acid-base, electrolyte and metabolite values. Therefore, we tested the hypothesis whether ultrafiltration of the prime and replacement with bicarbonate buffered hemofiltration solution (BB-HS) is sufficient for reducing the metabolic load

  17. In vitro dissolution of proton-pump inhibitor products intended for paediatric and geriatric use in physiological bicarbonate buffer.

    PubMed

    Liu, Fang; Shokrollahi, Honaz

    2015-05-15

    Proton-pump inhibitor (PPI) products based on enteric coated multiparticulates are design to meet the needs of patients who cannot swallow tablets such as children and older adults. Enteric coated PPI preparations exhibit delays in in vivo absorption and onset of antisecretory effects, which is not reflected by the rapid in vitro dissolution in compendial pH 6.8 phosphate buffer commonly used for assessment of these products. A more representative and physiological medium, pH 6.8 mHanks bicarbonate buffer, was used in this study to evaluate the in vitro dissolution of enteric coated multiparticulate-based PPI products. Commercially available omeprazole, lansoprazole and esomeprazole products were subject to dissolution tests using USP-II apparatus in pH 4.5 phosphate buffer saline for 45min (acid stage) followed by pH 6.8 phosphate buffer or pH 6.8 mHanks bicarbonate buffer. In pH 6.8 phosphate buffer, all nine tested products displayed rapid and comparable dissolution profiles meeting the pharmacopeia requirements for delayed release preparations. In pH 6.8 mHanks buffer, drug release was delayed and failed the pharmacopeia requirements from most enteric coated preparations. Despite that the same enteric polymer, methacrylic acid-ethyl acrylate copolymer (1:1), was applied to all commercial multiparticulate-based products, marked differences were observed between dissolution profiles of these preparations. The use of pH 6.8 physiological bicarbonate (mHanks) buffer can serve as a useful tool to provide realistic and discriminative in vitro release assessment of enteric coated PPI preparations and to assist rational formulation development of these products. PMID:25746736

  18. In vitro effects of bicarbonate and bicarbonate-lactate buffered peritoneal dialysis solutions on mesothelial and neutrophil function.

    PubMed

    Topley, N; Kaur, D; Petersen, M M; Jörres, A; Williams, J D; Faict, D; Holmes, C J

    1996-02-01

    The inclusion of bicarbonate in the formulation of peritoneal dialysis solutions may avoid the in vitro impairment of certain cell functions seen with acidic lactate-based fluids. The supranormal physiological levels of HCO3- and PCO2 inherent in such formulations may, however, not be biocompatible. This study compared the in vitro biocompatibility of a pH 5.2 lactate-based formulation with formulations containing either 40 mM lactate at pH 7.4, 38 mM HCO3- at pH 6.8 (PCO2 at approximately 240 mm Hg) or 7.4 (PCO2 at approximately 60 mm Hg), and 25 mM HCO3- plus 15 mM lactate at pH 6.8 (PCO2 at approximately 160 mm Hg) or 7.4 (PCO2 at approximately 40 mm Hg). Significant release of lactate dehydrogenase or decreases in ATP content by human peritoneal mesothelial cells (HPMC) and human peripheral polymorphonuclear leukocytes (PMN) after a 30-min exposure to each test solution was only seen with the pH 5.2 lactate-based fluid. The ATP content of HPMC exposed to this fluid returned to control levels after 30 min of recovery in M199 control medium but showed a trend toward decreasing ATP content at 240 min. Similarly, interleukin (IL)-1 beta-induced IL-6 synthesis by HPMC was also only significantly reduced by the pH 5.2 lactate solution. PMN chemiluminescence was unaffected by 30-min exposure to all test solutions except for the pH 5.2 lactate formulation. Staphylococcus epidermidis phagocytosis was reduced to between 46 to 57% of control with all test solutions except the pH 5.2 lactate solution, which further suppressed the chemiluminescence response to 17% of control. These data suggest that short exposure to supranormal physiological levels of HCO3- and PCO2 does not impair HPMC or PMN viability and function. Furthermore, neutral pH lactate-containing solutions show equivalent biocompatibility to bicarbonate-based ones. PMID:8785390

  19. Role of bicarbonate as a pH buffer and electron sink in microbial dechlorination of chloroethenes

    PubMed Central

    2012-01-01

    Background Buffering to achieve pH control is crucial for successful trichloroethene (TCE) anaerobic bioremediation. Bicarbonate (HCO3?) is the natural buffer in groundwater and the buffer of choice in the laboratory and at contaminated sites undergoing biological treatment with organohalide respiring microorganisms. However, HCO3? also serves as the electron acceptor for hydrogenotrophic methanogens and hydrogenotrophic homoacetogens, two microbial groups competing with organohalide respirers for hydrogen (H2). We studied the effect of HCO3? as a buffering agent and the effect of HCO3?-consuming reactions in a range of concentrations (2.5-30 mM) with an initial pH of 7.5 in H2-fed TCE reductively dechlorinating communities containing Dehalococcoides, hydrogenotrophic methanogens, and hydrogenotrophic homoacetogens. Results Rate differences in TCE dechlorination were observed as a result of added varying HCO3? concentrations due to H2-fed electrons channeled towards methanogenesis and homoacetogenesis and pH increases (up to 8.7) from biological HCO3? consumption. Significantly faster dechlorination rates were noted at all HCO3? concentrations tested when the pH buffering was improved by providing 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) as an additional buffer. Electron balances and quantitative PCR revealed that methanogenesis was the main electron sink when the initial HCO3? concentrations were 2.5 and 5 mM, while homoacetogenesis was the dominant process and sink when 10 and 30 mM HCO3? were provided initially. Conclusions Our study reveals that HCO3? is an important variable for bioremediation of chloroethenes as it has a prominent role as an electron acceptor for methanogenesis and homoacetogenesis. It also illustrates the changes in rates and extent of reductive dechlorination resulting from the combined effect of electron donor competition stimulated by HCO3? and the changes in pH exerted by methanogens and homoacetogens. PMID:22974059

  20. Better preservation of peritoneal morphologic features and defense in rats after long-term exposure to a bicarbonate/lactate-buffered solution.

    PubMed

    Hekking, L H; Zareie, M; Driesprong, B A; Faict, D; Welten, A G; de Greeuw, I; Schadee-Eestermans, I L; Havenith, C E; van den Born, J; ter Wee, P M; Beelen, R H

    2001-12-01

    The long-term effects of a standard lactate-buffered dialysis fluid and a new, two-chamber, bicarbonate/lactate-buffered dialysis fluid (with fewer glucose degradation products and a neutral pH) were compared in an in vivo peritoneal exposure model. Rats were given daily injections, via an access port, of 10 ml of standard solution or bicarbonate/lactate-buffered solution for 9 to 10 wk. The omentum, peritoneum, and mesothelial cell layer were screened for morphologic changes. In addition, the bacterial clearing capacity of the peritoneal cells was studied. Significantly more milky spots and blood vessels were observed in the omenta of animals treated with standard solution (P < 0.03 for both parameters). Electron-microscopic analysis demonstrated dramatic changes in the appearance of the vascular endothelial cells of the milky spots and a severely damaged or even absent mesothelium on the peritoneal membrane of the standard solution-treated animals. In contrast, the mesothelium was still present in the bicarbonate/lactate-buffered solution group, although the cells lost microvilli. Both peritoneal dialysis fluids significantly increased the density of mesothelial cells (per square millimeter) on the surface of the liver and the thickness of the submesothelial extracellular matrix of the peritoneum (both P < 0.04 for both fluids versus control). A significantly better ex vivo bacterial clearing capacity was observed with peritoneal cells from the bicarbonate/lactate-buffered solution group, compared with the standard solution group (P < 0.05 in both experiments). These results demonstrate that instillation of bicarbonate/lactate-buffered solution into rats for 9 to 10 wk preserves both morphologic and immune parameters much more effectively, compared with standard solution. These findings may be of considerable clinical importance. PMID:11729248

  1. Author's personal copy Evaluation of stainless steel cathodes and a bicarbonate buffer

    E-print Network

    production in microbial electrolysis cells using a new method for measuring gas production Jack R. Ambler: Biohydrogen Bioenergy Gas bag Buffer Electrohydrogenesis a b s t r a c t Microbial electrolysis cells (MECs. Published by Elsevier Ltd. All rights reserved. 1. Introduction A microbial electrolysis cell (MEC

  2. Coral reef calcifiers buffer their response to ocean acidification using both bicarbonate and carbonate.

    PubMed

    Comeau, S; Carpenter, R C; Edmunds, P J

    2013-02-22

    Central to evaluating the effects of ocean acidification (OA) on coral reefs is understanding how calcification is affected by the dissolution of CO(2) in sea water, which causes declines in carbonate ion concentration [CO(3)(2-)] and increases in bicarbonate ion concentration [HCO(3)(-)]. To address this topic, we manipulated [CO(3)(2-)] and [HCO(3)(-)] to test the effects on calcification of the coral Porites rus and the alga Hydrolithon onkodes, measured from the start to the end of a 15-day incubation, as well as in the day and night. [CO(3)(2-)] played a significant role in light and dark calcification of P. rus, whereas [HCO(3)(-)] mainly affected calcification in the light. Both [CO(3)(2-)] and [HCO(3)(-)] had a significant effect on the calcification of H. onkodes, but the strongest relationship was found with [CO(3)(2-)]. Our results show that the negative effect of declining [CO(3)(2-)] on the calcification of corals and algae can be partly mitigated by the use of HCO(3)(-) for calcification and perhaps photosynthesis. These results add empirical support to two conceptual models that can form a template for further research to account for the calcification response of corals and crustose coralline algae to OA. PMID:23256193

  3. Magnesium bicarbonate as an in situ uranium lixiviant

    SciTech Connect

    Sibert, J.W.

    1984-09-25

    In the subsurface solution mining of mineral values, especially uranium, in situ, magnesium bicarbonate leaching solution is used instead of sodium, potassium and ammonium carbonate and bicarbonates. The magnesium bicarbonate solution is formed by combining carbon dioxide with magnesium oxide and water. The magnesium bicarbonate lixivant has four major advantages over prior art sodium, potassium and ammonium bicarbonates.

  4. Detection of OXA-48-type carbapenemase-producing Enterobacteriaceae in diagnostic laboratories can be enhanced by addition of bicarbonates to cultivation media or reaction buffers.

    PubMed

    Studentova, Vendula; Papagiannitsis, Costas C; Izdebski, Radoslaw; Pfeifer, Yvonne; Chudackova, Eva; Bergerova, Tamara; Gniadkowski, Marek; Hrabak, Jaroslav

    2015-03-01

    Carbapenemase-mediated resistance to carbapenems in Enterobacteriaceae has become the main challenge in the treatment and prevention of infections recently. The partially unnoticed spread of OXA-48-type carbapenemase producers is usually assigned to low minimum inhibitory concentrations (MICs) of carbapenems that OXA-48-producing isolates often display. Therefore, there is an urgent need of specific and sensitive methods for isolation and detection of OXA-48 producers in clinical microbiology diagnostics. The influence of bicarbonates on carbapenem MICs against carbapenemase-producing Enterobacteriaceae was tested. We also checked whether the addition of bicarbonates to liquid media supplemented with meropenem may facilitate the selective enrichment of various carbapenemase producers in cultures. Furthermore, the sensitivity of carbapenemase confirmation by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-TOF MS) and spectrophotometric hydrolysis assays upon the addition of NH4HCO3 was examined. The addition of NaHCO3 significantly increased MICs of ertapenem and meropenem for OXA-48 producers. Furthermore, liquid media supplemented with NaHCO3 and meropenem were reliable for the selective enrichment of carbapenemase producers. The presence of NH4HCO3 in buffers used in the spectrophotometric and MALDI-TOF MS carbapenemase detection increased the sensitivity of that assay. Our results demonstrate that bicarbonates in media or reaction buffers can enhance the sensitivity of screening methods and diagnostic tests for carbapenemase producers. PMID:25261959

  5. Predicting the gastrointestinal behaviour of modified-release products: utility of a novel dynamic dissolution test apparatus involving the use of bicarbonate buffers.

    PubMed

    Merchant, Hamid A; Goyanes, Alvaro; Parashar, Narendra; Basit, Abdul W

    2014-11-20

    The establishment of physiologically relevant in vitro-in vivo correlations (IV-IVCs) is key for any biorelevant dissolution test. Historically, bicarbonate buffers have produced better correlations than compendial phosphate buffered media, though such tests are usually performed at a constant pH experiment, overlooking the notion that the pH of the luminal fluids is variable and fluctuating. In this work, we have devised a dynamic dissolution test method employing a physiological bicarbonate buffer under pH conditions of the proximal gut in order to assess the dissolution behaviour of various enteric polymer-coated (gastro-resistant) prednisolone tablets. The pH of the media is modulated and controlled by an Auto pH System™ which exploits the physiological equilibria between [H2CO3] and [HCO3(-)], to match it to the aboral change in pH with transit of the dosage form through the proximal small intestine (from pH 5.6 up to 6.8). The lag time values for an accelerated release and standard EUDRAGIT(®) L30D-55 coated formulation (25 min and 60 min, respectively) were close to the previously reported initial tablet disintegration time data obtained in-vivo by ?-scintigraphy (28 min and 66 min, respectively). Dissolution of alternative delayed release coated products was also better discriminated in the dynamic buffer system. These data confirm the dynamic dissolution system provides a robust and reliable platform to predict the in vivo fate of oral products in a laboratory setting. PMID:25195730

  6. Continuous dialysis with bicarbonate/lactate-buffered peritoneal dialysis fluids results in a long-term improvement in ex vivo peritoneal macrophage function.

    PubMed

    Jones, Suzanne; Holmes, Clifford J; Mackenzie, Ruth K; Stead, Rachel; Coles, Gerald A; Williams, John D; Faict, Dirk; Topley, Nicholas

    2002-01-01

    To circumvent the potentially negative consequences of long-term exposure to unphysiologic acidic lactate-buffered peritoneal dialysis fluids (PDF), neutral pH solutions buffered with bicarbonate/lactate have recently been introduced in phase 2 and 3 clinical trials. This study examines the longitudinal changes in peritoneal macrophage (PMØ) function in patients dialyzed continuously with either lactate (LPD; 40 mM lactate, pH 5.2)-buffered or bicarbonate/lactate (TBL; 25 mM/15 mM bicarbonate/lactate, pH 7.3)-buffered PDF. Before the study, during the run in period of a phase 3 clinical trial, all patients had been taking LPD for at least the previous 18 wk. At the beginning of the study (day 0), both constitutive and serum-treated zymosan (STZ) stimulated tumor necrosis factor alpha (TNF-alpha) synthesis were assessed in PMØ isolated from 12-h dwell effluent (with 1.36% glucose) in all patients. The patients were subsequently randomized to either continuous TBL or LPD therapy and PMØ function was assessed after further 3- and 6-mo periods in all patients. At all time points measured STZ induced a dose-dependent increase in PMØ TNF-alpha secretion (P = 0.043 versus control for doses greater than 100 microg/ml). In patients continuously dialyzed with LPD, constitutive PMØ TNF-alpha synthesis levels (mean +/- SEM, pg/10(6) PMØ per18 h, n = 5 patients) were 154 +/- 65, 261 +/- 60, and 101 +/- 99 at 0, 3, and 6 mo, respectively. Stimulated STZ (1000 microg/ml) levels were 1340 +/- 519, 1046 +/- 586, and 758 +/- 250 at 0, 3, and 6 mo, respectively. In patients dialyzed with TBL, constitutive PMØ TNF-alpha synthesis levels (pg/10(6) PMØ per 18 h, n = 5 patients) were 300 +/- 136, 106 +/- 35, and 213 +/- 62 at 0, 3, and 6 mo, respectively. Stimulated STZ (1000 microg/ml) levels were 1969 +/- 751, 1541 +/- 330, and 2670 +/- 671 at 0, 3, and 6 mo, respectively. At 6 mo, STZ-stimulated PMØ TNF-alpha synthesis was significantly higher in patients treated with TBL compared with those treated with LPD (P = 0.0035). These data suggest that in patients continuously dialyzed with a neutral pH solution, there is a long-term improvement in PMØ function compared with patients on conventional therapy. Better PMØ function suggests improved host defense status and may affect the peritoneum's susceptibility to infection and potentially reduce the negative consequences of repeated intraperitoneal inflammation on long-term membrane function. PMID:11792769

  7. Internal Active Thermal Control System (IATCS) Sodium Bicarbonate/Carbonate Buffer in an Open Aqueous Carbon Dioxide System and Corollary Electrochemical/Chemical Reactions Relative to System pH Changes

    NASA Technical Reports Server (NTRS)

    Stegman, Thomas W.; Wilson, Mark E.; Glasscock, Brad; Holt, Mike

    2014-01-01

    The International Space Station (ISS) Internal Active Thermal Control System (IATCS) experienced a number of chemical changes driven by system absorption of CO2 which altered the coolant’s pH. The natural effects of the decrease in pH from approximately 9.2 to less than 8.4 had immediate consequences on system corrosion rates and corrosion product interactions with specified coolant constituents. The alkalinity of the system was increased through the development and implementation of a carbonate/bicarbonate buffer that would increase coolant pH to 9.0 – 10.0 and maintain pH above 9.0 in the presence of ISS cabin concentrations of CO2 up to twenty times higher than ground concentrations. This paper defines how a carbonate/bicarbonate buffer works in an open carbon dioxide system and summarizes the analyses performed on the buffer for safe and effective application in the on-orbit system. The importance of the relationship between the cabin environment and the IATCS is demonstrated as the dominant factor in understanding the system chemistry and pH trends before and after addition of the carbonate/bicarbonate buffer. The paper also documents the corollary electrochemical and chemical reactions the system has experienced and the rationale for remediation of these effects with the addition of the carbonate/bicarbonate buffer.

  8. Evaluation of the effect of trypsin digestion buffers on artificial deamidation.

    PubMed

    Hao, Piliang; Ren, Yan; Datta, Arnab; Tam, James P; Sze, Siu Kwan

    2015-02-01

    Nonenzymatic deamidation occurs readily under the condition of trypsin digestion, resulting in the identification of many artificial deamidation sites. To evaluate the effect of trypsin digestion buffers on artificial deamidation, we compared the three commonly used buffers Tris-HCl (pH 8), ammonium bicarbonate (ABC), and triethylammonium bicarbonate (TEAB), and ammonium acetate (pH 6), which was reported to reduce Asn deamidation. iTRAQ quantification on rat kidney tissue digested in these four buffers indicates that artificial Asn deamidation is produced in the order of ammonium acetate < Tris-HCl < ABC < TEAB, and Gln deamidation has no significant differences in all tested buffers. Label-free experiments show the same trend, while protein and unique peptide identification are comparable using these four buffers. To explain the differences of these four buffers in producing artificial Asn deamidation, we determined the half-life of Asn deamidation in these buffers using synthetic peptides containing -Asn-Gly- sequences. It is 51.4 ± 6.0 days in 50 mM of ammonium acetate (pH 6) at 37 °C, which is about 23, 104, and 137 times that in Tris-HCl, ABC, and TEAB buffers, respectively. In conclusion, ammonium acetate (pH 6) is more suitable than other tested buffers for characterizing endogenous deamidation and N-glycosylation. PMID:25495137

  9. Effect of two-chambered bicarbonate lactate-buffered peritoneal dialysis fluids on peripheral blood mononuclear cell and polymorphonuclear cell function in vitro.

    PubMed

    Sundaram, S; Cendoroglo, M; Cooker, L A; Jaber, B L; Faict, D; Holmes, C J; Pereira, B J

    1997-11-01

    Low pH, high osmolality, increasing glucose concentration, and glucose degradation products (GDP) formed during heat sterilization of conventional peritoneal dialysis (PD) fluids have been shown to have a detrimental effect on cells involved in peritoneal host defense. The two-chambered PD fluid bag in which glucose at pH approximately 3 is separated from a bicarbonate (25 mmol/L)-lactate (15 mmol/L) buffer during heat sterilization permits PD fluids with lower GDP to be delivered to the patient at neutral pH. To establish the possible benefit of two-chambered bag PD fluids on peripheral blood mononuclear cell (PBMC) and polymorphonuclear (PMN) cell function, we compared conventional 1.5% Dianeal (1.5%D) with 1.5% two-chambered bag bicarbonate-lactate (1.5%D-B), and conventional 4.25% Dianeal (4.25%D) with 4.25% two-chambered bag bicarbonate-lactate (4.25%D-B). Furthermore, to study the effect of the sterilization process on PBMC and PMN function, we compared filter-sterilized 4.25%D (4.25%D-F) with 4.25%D and 4.25%D-B. PBMC were harvested by Ficoll-Hypaque separation, and 2.5 x 10(6) cells in RPMI were incubated with an equal volume of the test fluids for 4 hours, pelleted, and resuspended in RPMI containing 10 ng endotoxin for a further 20 hours. Tumor necrosis factor alpha (TNF-alpha) production by endotoxin-stimulated PBMC was not significantly different (P = 0.10) between 1.5%D-B and 1.5%D, but was significantly higher (P = 0.01) with 4.25%D-B compared with 4.25%D. PBMC exposed to filter-sterilized fluid (4.25%D-F) showed significantly higher endotoxin-stimulated TNF-alpha production compared with 4.25%D (P = 0.02), but was not significantly different from 4.25%D-B (P = 0.40). PMN were harvested by Ficoll-Hypaque separation and 10 x 10(6) cells incubated with test fluids for 30 minutes. After incubation, phagocytosis (phagocytosis index) was determined by the uptake of 14C-labeled Staphylococcus aureus, oxidative burst by reduction of ferricytochrome C to ferrocytochrome C on stimulation with PMA, and enzyme release by measurement of endotoxin-stimulated bactericidal/permeability increasing protein (BPI). Bicarbonate-lactate two-chambered fluids of similar osmolality and glucose concentration conferred a significant improvement in phagocytosis (P = 0.02 for 1.5%D-B and P < 0.001 for 4.25%D-B). Oxidative burst and BPI release were significantly higher in 4.25%D-B compared with 4.25%D (P < 0.001). Filter-sterilized 4.25%D-F conferred a significant improvement in phagocytosis and oxidative burst compared with 4.25%D (P < 0.001) or 4.25%D-B (P < 0.001). Furthermore, conventional 4.25%D was associated with significantly lower BPI release compared with 4.25%D-F (P = 0.01). GDP's acetaldehyde and 5-HMF were analyzed in 4.25%D-B, 4.25%D, and 4.25%D-F. Acetaldehyde was below the lower limit (0.79 ppm) of the standard curve in 4.25%D-B and 4.25%D-F fluids but was detected (3.76 to 5.12 ppm) in all of the 4.25%D fluids. Relative levels of 5-HMF in the 4.25%D-B (0.032 to 0.041 Abs @ 284 nm) and 4.25%D (0.031 to 0.036 Abs @ 284 nm) were similar. The lowest levels (0.001 Abs @ 284 nm) were observed in the filter-sterilized 4.25%D-F. The beneficial effects of two-chambered bicarbonate lactate-buffered PD fluids on PBMC and PMN function are probably related to reduction of GDP from heat sterilization of glucose in a separate chamber at a lower pH. This improvement in biocompatibility could have a beneficial affect on peritoneal defenses. PMID:9370184

  10. Sodium Bicarbonate

    MedlinePLUS

    Sodium bicarbonate comes as a tablet and powder to take by mouth. Sodium bicarbonate is taken one to four times a day, depending on the reason you ... flecainide (Tambocor), iron, ketoconazole (Nizoral), lithium (Eskalith, ... Urex), methotrexate, quinidine, sulfa-containing antibiotics, tetracycline ( ...

  11. Method of uranium reclamation from aqueous systems by reactive ion exchange. [US DOE patent application; anion exchange resin of copolymerized divinyl-benzene and styrene having quarternary ammonium groups and bicarbonate ligands

    DOEpatents

    Maya, L.

    1981-11-05

    A reactive ion exchange method for separation and recovery of values of uranium, neptunium, plutonium, or americium from substantially neutral aqueous systems of said metals comprises contacting said system with an effective amount of a basic anion exchange resin of copolymerized divinyl-benzene and styrene having quarternary ammonium groups and bicarbonate ligands to achieve nearly 100% sorption of said actinyl ion onto said resin and an aqueous system practically free of said actinyl ions. The method is operational over an extensive range of concentrations from about 10/sup -6/ M to 1.0 M actinyl ion and a pH range of about 4 to 7. The method has particulr application to treatment of waste streams from Purex-type nuclear fuel reprocessing facilities and hydrometallurgical processes involving U, Np, P, or Am.

  12. Composition and Reactions of Liquid Manure (Gülle), with Particular Reference to Phosphate: III. pH-Buffering Capacity and Organic Components1

    Microsoft Academic Search

    A. W. Fordham; U. Schwertmann

    1977-01-01

    pH titrations of giille samples disclosed differences of composi- tion related to origin, age, and storage conditions prior to collec- tion. Buffering capacities depended partly on ammonium bicarbon- ate content, which fluctuated from sample to sample but increased during laboratory storage, at 4C or room temperature. Organic compounds both in solution and solid phases buffered in the lower pH ranges,

  13. Influence of temperature, chloride ions and chromium element on the electronic property of passive film formed on carbon steel in bicarbonate\\/carbonate buffer solution

    Microsoft Academic Search

    D. G. Li; Y. R. Feng; Z. Q. Bai; J. W. Zhu; M. S. Zheng

    2007-01-01

    The influences of temperature, chloride ions and chromium element on the electronic property of passive film formed on carbon steel in NaHCO3\\/Na2CO3 buffer solution are investigated by capacitance measurement and electrochemical impedance spectroscopy (EIS). The results show that the passive film appears n-type semiconductive character; with increasing the solution temperature, the addition of chromium into carbon steel and increasing the

  14. Bicarbonate Availability for Vocal Fold Epithelial Defense to Acidic Challenge

    PubMed Central

    Durkes, Abigail; Sivasankar, M. Preeti

    2014-01-01

    Objectives Bicarbonate is critical for acid-base tissue homeostasis. In this study we investigated the role of bicarbonate ion transport in vocal fold epithelial defense to acid challenges. Acidic insults to the larynx are common in gastric reflux, carcinogenesis and metastasis, and acute inflammation. Methods Ion transport was measured in viable, porcine vocal fold epithelium. First, 18 vocal folds were exposed to either the carbonic anhydrase antagonist acetazolamide or to vehicle. Second, 32 vocal folds were exposed to either a control buffer or a bicarbonate-free buffer on their luminal or basolateral surface or both. Third, vocal folds were challenged with acid in the presence of bicarbonate-free or control buffer. Results The vocal fold transepithelial resistance was greater than 300 ?*cm2, suggesting robust barrier integrity. Ion transport did not change after exposure to acetazolamide (p > 0.05). Exposure to bicarbonate-free buffer did not compromise vocal fold ion transport (p > 0.05). Ion transport increased after acid challenge. This increase approached statistical significance and was the greatest for the control buffer and for the bicarbonate-free buffer applied to the basolateral surface. Conclusions Bicarbonate secretion may contribute to vocal fold defense against acid challenge. Our data offer a potential novel role for bicarbonate as a therapeutic agent to reduce pH abnormalities in the larynx and prevent associated pathological changes. PMID:24574427

  15. 21 CFR 184.1135 - Ammonium bicarbonate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...ingredient is based upon the following current good manufacturing practice conditions of use: (1) The ingredient is used as a dough strengthener as defined in § 170.3(o)(6) of this chapter; a leavening agent as defined in § 170.3(o)(17)...

  16. 21 CFR 184.1135 - Ammonium bicarbonate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...ingredient is based upon the following current good manufacturing practice conditions of use: (1) The ingredient is used as a dough strengthener as defined in § 170.3(o)(6) of this chapter; a leavening agent as defined in § 170.3(o)(17)...

  17. 21 CFR 184.1137 - Ammonium carbonate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...Reg. No. 8000-73-5) is a mixture of ammonium bicarbonate (NH4 HCO3 ) and ammonium carbamate (NH2 COONH4 ). It is prepared by the sublimation of a mixture of ammonium sulfate and calcium carbonate and occurs as a...

  18. 21 CFR 184.1137 - Ammonium carbonate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...Reg. No. 8000-73-5) is a mixture of ammonium bicarbonate (NH4 HCO3 ) and ammonium carbamate (NH2 COONH4 ). It is prepared by the sublimation of a mixture of ammonium sulfate and calcium carbonate and occurs as a...

  19. 21 CFR 184.1137 - Ammonium carbonate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...Reg. No. 8000-73-5) is a mixture of ammonium bicarbonate (NH4 HCO3 ) and ammonium carbamate (NH2 COONH4 ). It is prepared by the sublimation of a mixture of ammonium sulfate and calcium carbonate and occurs as a...

  20. 21 CFR 184.1137 - Ammonium carbonate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...Reg. No. 8000-73-5) is a mixture of ammonium bicarbonate (NH4 HCO3 ) and ammonium carbamate (NH2 COONH4 ). It is prepared by the sublimation of a mixture of ammonium sulfate and calcium carbonate and occurs as a...

  1. 21 CFR 184.1137 - Ammonium carbonate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...Reg. No. 8000-73-5) is a mixture of ammonium bicarbonate (NH4 HCO3 ) and ammonium carbamate (NH2 COONH4 ). It is prepared by the sublimation of a mixture of ammonium sulfate and calcium carbonate and occurs as a...

  2. Ammonium metabolism in humans.

    PubMed

    Adeva, Maria M; Souto, Gema; Blanco, Natalia; Donapetry, Cristóbal

    2012-11-01

    Free ammonium ions are produced and consumed during cell metabolism. Glutamine synthetase utilizes free ammonium ions to produce glutamine in the cytosol whereas glutaminase and glutamate dehydrogenase generate free ammonium ions in the mitochondria from glutamine and glutamate, respectively. Ammonia and bicarbonate are condensed in the liver mitochondria to yield carbamoylphosphate initiating the urea cycle, the major mechanism of ammonium removal in humans. Healthy kidney produces ammonium which may be released into the systemic circulation or excreted into the urine depending predominantly on acid-base status, so that metabolic acidosis increases urinary ammonium excretion while metabolic alkalosis induces the opposite effect. Brain and skeletal muscle neither remove nor produce ammonium in normal conditions, but they are able to seize ammonium during hyperammonemia, releasing glutamine. Ammonia in gas phase has been detected in exhaled breath and skin, denoting that these organs may participate in nitrogen elimination. Ammonium homeostasis is profoundly altered in liver failure resulting in hyperammonemia due to the deficient ammonium clearance by the diseased liver and to the development of portal collateral circulation that diverts portal blood with high ammonium content to the systemic blood stream. Although blood ammonium concentration is usually elevated in liver disease, a substantial role of ammonium causing hepatic encephalopathy has not been demonstrated in human clinical studies. Hyperammonemia is also produced in urea cycle disorders and other situations leading to either defective ammonium removal or overproduction of ammonium that overcomes liver clearance capacity. Most diseases resulting in hyperammonemia and cerebral edema are preceded by hyperventilation and respiratory alkalosis of unclear origin that may be caused by the intracellular acidosis occurring in these conditions. PMID:22921946

  3. Solubility of ammonium acid urate nephroliths from bottlenose dolphins (Tursiops truncatus).

    PubMed

    Argade, Sulabha; Smith, Cynthia R; Shaw, Timothy; Zupkas, Paul; Schmitt, Todd L; Venn-Watson, Stephanie; Sur, Roger L

    2013-12-01

    Nephrolithiasis has been identified in managed populations of bottlenose dolphins (Tursiops truncatus); most of these nephroliths are composed of 100% ammonium acid urate (AAU). Several therapies are being investigated to treat and prevent nephrolithiasis in dolphins including the alkalization of urine for dissolution of nephroliths. This study evaluates the solubility of AAU nephroliths in a phosphate buffer, pH range 6.0-8.0, and in a carbonate-bicarbonate buffer, pH range 9.0-10.8. AAU nephroliths were obtained from six dolphins and solubility studies were conducted using reverse-phase high performance liquid chromatography with ultraviolet detection at 290 nm. AAU nephroliths were much more soluble in a carbonate-bicarbonate buffer, pH range 9.0-10.8 compared to phosphate buffer pH range 6.0-8.0. In the pH range 6.0-8.0, the solubility was 45% lower in potassium phosphate buffer compared to sodium phosphate buffer. When citrate was used along with phosphate in the same pH range, the solubility was improved by 13%. At pH 7 and pH 8, 150 mM ionic strength buffer was optimum for dissolution. In summary, adjustment of urinary pH alone does not appear to be a useful way to treat AAU stones in bottlenose dolphins. Better understanding of the pathophysiology of AAU nephrolithiasis in dolphins is needed to optimize kidney stone prevention and treatment. PMID:24450043

  4. Amplification of GC-rich Putative Mouse PeP Promoter using Betaine and DMSO in Ammonium Sulfate Polymerase Chain Reaction Buffer

    PubMed Central

    Seifi, Tahere; Ghaedi, Kamran; Salamian, Ahmad; Tanhaei, Sommayeh; Safari, Forouzan; Hojati, Zohreh; Tavassoli, Manuchehr; Baharvand, Hossein; Esfahani, Mohammad-Hossein Nasr

    2012-01-01

    Background Recently, we have shown that peroxisomal protein expression was induced upon retinoic acid treatment in mouse embryonic stem cells during the process of neurogenesis. Thus, characterization of the respective promoter could elucidate the molecular aspects of transcriptional regulation of this gene. Methods Using the conventional software programs for promoter prediction, a putative promoter region was identified approximately 561 bp upstream of the peroxisomal protein coding sequence. In order to clone this region with a GC-content of 71.01%, a cocktail of ammonium sulfate buffer supplied with two additive components, betaine and dimethyl sulfoxide, and a high concentration of MgCl2 was used. Results The modulated polymerase chain reaction composition significantly improved the amplification of GC-rich DNA target sequences. Improved amplification of this region was due to reduction in the formation of secondary structures by the GC-rich region. Conclusion Therefore, this polymerase chain reaction composition could be generally used to facilitate the amplification of other GC-rich DNA sequences as verified by amplification of different GC rich regions. PMID:23408119

  5. Use of Trialkyl Ammonium Phosphate (TAAP) Buffers in Reverse Phase HPLC for High Resolution and High Recovery of Peptides and Proteins

    Microsoft Academic Search

    Jean E. Rivier

    1978-01-01

    A new buffer system compatible with reverse phase high pressure liquid chromatography (RP -HPLC) column packings and giving high recoveries and high resolution for peptides and proteins is described. The TEAP buffer (triethylammonium phosphate), one of several TAAP buffers (trialkylammonium phosphate) compatible with RP-HPLC, gives high resolution and high recovery for closely related peptides or proteins as well as day

  6. Sodium Bicarbonate Therapy in Patients with Metabolic Acidosis

    PubMed Central

    Adeva-Andany, María M.; Fernández-Fernández, Carlos; Mouriño-Bayolo, David; Castro-Quintela, Elvira; Domínguez-Montero, Alberto

    2014-01-01

    Metabolic acidosis occurs when a relative accumulation of plasma anions in excess of cations reduces plasma pH. Replacement of sodium bicarbonate to patients with sodium bicarbonate loss due to diarrhea or renal proximal tubular acidosis is useful, but there is no definite evidence that sodium bicarbonate administration to patients with acute metabolic acidosis, including diabetic ketoacidosis, lactic acidosis, septic shock, intraoperative metabolic acidosis, or cardiac arrest, is beneficial regarding clinical outcomes or mortality rate. Patients with advanced chronic kidney disease usually show metabolic acidosis due to increased unmeasured anions and hyperchloremia. It has been suggested that metabolic acidosis might have a negative impact on progression of kidney dysfunction and that sodium bicarbonate administration might attenuate this effect, but further evaluation is required to validate such a renoprotective strategy. Sodium bicarbonate is the predominant buffer used in dialysis fluids and patients on maintenance dialysis are subjected to a load of sodium bicarbonate during the sessions, suffering a transient metabolic alkalosis of variable severity. Side effects associated with sodium bicarbonate therapy include hypercapnia, hypokalemia, ionized hypocalcemia, and QTc interval prolongation. The potential impact of regular sodium bicarbonate therapy on worsening vascular calcifications in patients with chronic kidney disease has been insufficiently investigated. PMID:25405229

  7. Abstract: We report the use of bicarbonate salts as viable alter-natives to more expensive bases for the in situ generation of

    E-print Network

    Lectka, Thomas

    the deprotonation of the acyl ammonium salt. Scheme 1. Mechanism of -Lactam Formation with Sodium Bicarbonate O Cl R1 LETTER Abstract: We report the use of bicarbonate salts as viable alter- natives to more applied this to the catalytic, asymmetric synthesis of -lactams. Key words: -lactam, bicarbonate salts

  8. A Modified o-Phthalaldehyde Fluorometric Analytical Method for Ultratrace Ammonium in Natural Waters Using EDTA-NaOH as Buffer

    PubMed Central

    Hu, Hongzhi; Li, Shuo; Guo, Qing; Wu, Chancui

    2014-01-01

    In the existence of appropriate amount of disodium ethylenediaminetetraacetate (EDTA), precipitation would not occur in seawater and other natural waters even if the sample solution was adjusted to strong basicity, and the NH3-OPA-sulfite reaction at the optimal pH range could be used to determine ammonium in natural waters. Based on this, a modified o-phthalaldehyde fluorometric analytical method has been established to determine ultratrace ammonium in natural waters. Experimental parameters, including reagent concentration, pH, reaction time, and effect of EDTA, were optimized throughout the experiments based on univariate experimental design. The results showed that the optimal pH range was between 10.80 and 11.70. EDTA did not obviously affect the fluorometric intensity. The linearity range of the proposed method was 0.032–0.500?µmol/L, 0.250–3.00?µmol/L, and 1.00–20.0?µmol/L at the excitation/emission slit of 3?nm/5?nm, 3?nm/3?nm, and 1.5?nm/1.5?nm, respectively. The method detection limit was 0.0099?µmol/L. Compared to the classical OPA method, the proposed method had the advantage of being more sensitive and could quantify ultratrace ammonium without enrichment. PMID:25436173

  9. Addition of Sodium Bicarbonate to Rations of Pre and Postpartum Dairy Cows1

    Microsoft Academic Search

    L. H. Kilmer; L. D. Muller; P. J. Wangsness

    1980-01-01

    Sodium bicarbonate was added to complete mixed rations to evaluate the effect of buffer addition on adaptation to high-energy rations by dairy cows in early lactation. Forty-five Holstein cows were assigned to one of three treatment groups: control pre- and postpartum; control prepartum, buffer postpartum; and buffer pre- and postpartum. Rations consisted of 85% chopped grass hay: 15% concentrate prepartum

  10. Addition of Sodium Bicarbonate to Rations of Postpartum Dairy Cows: Physiological and Metabolic Effects1

    Microsoft Academic Search

    L. H. Kilmer; L. D. Muller; T. J. Snyder

    1981-01-01

    Sodium bicarbonate was added to complete mixed rations to characterize physiological, metabolic, and ruminal changes immediately postpartum when dairy cows are switched abruptly from a low energy ration prepartum to a high energy ration postpartum. Twelve Holstein cows were paired and assigned randomly to either a control or buffered ration containing .8% sodium bicarbonate. Ra- tions consisted of 50% corn

  11. Predicting the safety and efficacy of buffer therapy to raise tumour pHe: an integrative modelling study

    E-print Network

    Maini, Philip K.

    .bjcancer.com Published online 1 March 2012 & 2012 Cancer Research UK Keywords: sodium bicarbonate; acidity; mathematical of blood and tumour buffering to examine the impact of oral administration of bicarbonate buffer in mice unseen potentially dangerous elevation in blood pHe resulting from bicarbonate therapy in mice, which

  12. Pancreatic Bicarbonate Secretion Involves Two Proton Pumps*

    PubMed Central

    Novak, Ivana; Wang, Jing; Henriksen, Katrine L.; Haanes, Kristian A.; Krabbe, Simon; Nitschke, Roland; Hede, Susanne E.

    2011-01-01

    Pancreas secretes fluid rich in digestive enzymes and bicarbonate. The alkaline secretion is important in buffering of acid chyme entering duodenum and for activation of enzymes. This secretion is formed in pancreatic ducts, and studies to date show that plasma membranes of duct epithelium express H+/HCO3? transporters, which depend on gradients created by the Na+/K+-ATPase. However, the model cannot fully account for high-bicarbonate concentrations, and other active transporters, i.e. pumps, have not been explored. Here we show that pancreatic ducts express functional gastric and non-gastric H+-K+-ATPases. We measured intracellular pH and secretion in small ducts isolated from rat pancreas and showed their sensitivity to H+-K+ pump inhibitors and ion substitutions. Gastric and non-gastric H+-K+ pumps were demonstrated on RNA and protein levels, and pumps were localized to the plasma membranes of pancreatic ducts. Quantitative analysis of H+/HCO3? and fluid transport shows that the H+-K+ pumps can contribute to pancreatic secretion in several species. Our results call for revision of the bicarbonate transport physiology in pancreas, and most likely other epithelia. Furthermore, because pancreatic ducts play a central role in several pancreatic diseases, it is of high relevance to understand the role of H+-K+ pumps in pathophysiology. PMID:20978133

  13. Practical considerations for bicarbonate loading and sports performance.

    PubMed

    Burke, Louise M

    2013-01-01

    Consumption of sodium bicarbonate (300 mg/kg 1-2 h before exercise) can temporarily increase blood bicarbonate concentrations, enhancing extracellular buffering of hydrogen ions which accumulate and efflux from the working muscle. Such 'bicarbonate loading' provides an ergogenic strategy for sporting events involving high rates of anaerobic glycolysis which are otherwise limited by the body's capacity to manage the progressive increase in intracellular acidity. Studies show that bicarbonate loading strategies have a moderate positive effect on the performance of sports involving 1-7 min of sustained strenuous exercise, and may also be useful for prolonged sports involving intermittent or sustained periods of high-intensity work rates. This potential to enhance sports performance requires further investigation using appropriate research design, but may be limited by practical considerations such as gut discomfort or the logistics of the event. The effect of chronic use of bicarbonate supplementation prior to high-intensity workouts to promote better training performance and adaptations is worthy of further investigation. While this relatively simple dietary strategy has been studied and used by sports people for over 80 years, it is likely that there are still ways in which further benefits from bicarbonate supplementation can be developed and individualized for specific athletes or specific events. PMID:23765347

  14. Sodium bicarbonate: basically useless therapy.

    PubMed

    Aschner, Judy L; Poland, Ronald L

    2008-10-01

    Common clinical practices often are unsupported by experimental evidence. One example is the administration of sodium bicarbonate to neonates. Despite a long history of widespread use, objective evidence that administration of sodium bicarbonate improves outcomes for patients in cardiopulmonary arrest or with metabolic acidosis is lacking. Indeed, there is evidence that this therapy is detrimental. This review examines the history of sodium bicarbonate use in neonatology and the evidence that refutes the clinical practice of administering sodium bicarbonate during cardiopulmonary resuscitation or to treat metabolic acidosis in the NICU. PMID:18829808

  15. DIETHANOLAMINE-CARBON DIOXIDE BUFFER PRODUCES ETHYLENE

    EPA Science Inventory

    Carbon dioxide concentrates in containers are frequently controlled by using a diethanolamine-bicarbonate buffer. Current studies show that this buffer produces ethylene and that the production increases with increasing pH and/or time in the incubation vessel. Ethylene is not pro...

  16. Short Communication Saline catholytes as alternatives to phosphate buffers in microbial

    E-print Network

    2013 Keywords: Microbial fuel cell Buffer Sodium chloride Ion exchange membrane a b s t r a c t HighlyH conditions and increase the solution conduc- tivity, including phosphate, bicarbonate, and zwitterionic (Fan into the environment. Bicarbonate buffers are more useful, but they can enhance the growth of methanogens (Fan et al

  17. Rod phototransduction modulated by bicarbonate in the frog retina: roles of carbonic anhydrase and bicarbonate exchange.

    PubMed Central

    Donner, K; Hemilä, S; Kalamkarov, G; Koskelainen, A; Shevchenko, T

    1990-01-01

    1. Effects on rod phototransduction following manipulation of retinal CO2-HCO3- and H+ fluxes were studied in dark-adapted retinas of the frog and the tiger salamander. 2. Rod photoresponses to brief flashes of light were recorded from the isolated sensory retina as electroretinogram mass receptor potentials and from isolated rods by the suction-pipette technique. The experimental treatments were: (1) varying [CO2] + [HCO3-] in the perfusion fluid: (2) applying acetazolamide (AAA), which inhibits the enzyme carbonic anhydrase (CA); and (3) applying 4,4'-diisothiocyanatostilbene-2,2'-disulphonic acid (DIDS) which blocks exchange mechanisms transporting HCO3- across cell membranes. 3. The concentration of the internal transmitter of the rods, cyclic GMP, was biochemically determined from the rod outer segment layer of retinas that had been incubated in the same solutions as were used for perfusion in the electrophysiological experiments. 4. The introduction of 6 mM-sodium bicarbonate to replace half the buffer of a nominally CO2-HCO3(-)-free (12 mM-phosphate or HEPES, [Na+] constant) Ringer solution doubled the cyclic GMP concentration in the rod outer segment layer and increased the saturating response amplitude and the relative sensitivity of rods in the intact retina. 5. The introduction of 0.5 mM-AAA into bicarbonate-containing Ringer solution accelerated the growth of saturated responses and sensitivity. Incubation of the retina in AAA-bicarbonate Ringer solution elevated the concentration of cyclic GMP ninefold compared with the phosphate control. 6. No effects of switching to bicarbonate-AAA Ringer solution were observed in the photocurrent of isolated rods drawn into suction pipettes with only the outer segment protruding into the perfusion fluid. The target of AAA is probably the CA-containing Müller cell. 7. The introduction of DIDS into the perfusate (at normal pH 7.5) set off a continuous decay of photoresponses which finally abolished light sensitivity completely. The decay proceeded regardless of whether bicarbonate and AAA were present or not. 8. Rods that had lost their photosensitivity in DIDS recovered almost fully when the pH of the DIDS perfusate was raised to 8.5. They also recovered when DIDS was washed out with bicarbonate Ringer solution at constant pH (7.5). 9. It is proposed that all our treatments ultimately modulate the intracellular pH of the rods which is determined by the relative rates of H+ leakage and HCO3- transport into the cells.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:2172515

  18. Buffer Therapy for Cancer

    PubMed Central

    Ribeiro, Maria de Lourdes C; Silva, Ariosto S.; Bailey, Kate M.; Kumar, Nagi B.; Sellers, Thomas A.; Gatenby, Robert A.; Ibrahim-Hashim, Arig; Gillies, Robert J.

    2013-01-01

    Oral administration of pH buffers can reduce the development of spontaneous and experimental metastases in mice, and has been proposed in clinical trials. Effectiveness of buffer therapy is likely to be affected by diet, which could contribute or interfere with the therapeutic alkalinizing effect. Little data on food pH buffering capacity was available. This study evaluated the pH and buffering capacity of different foods to guide prospective trials and test the effect of the same buffer (lysine) at two different ionization states. Food groups were derived from the Harvard Food Frequency Questionnaire. Foods were blended and pH titrated with acid from initial pH values until 4.0 to determine “buffering score”, in mmol H+/pH unit. A “buffering score” was derived as the mEq H+ consumed per serving size to lower from initial to a pH 4.0, the postprandial pH of the distal duodenum. To differentiate buffering effect from any metabolic byproduct effects, we compared the effects of oral lysine buffers prepared at either pH 10.0 or 8.4, which contain 2 and 1 free base amines, respectively. The effect of these on experimental metastases formation in mice following tail vein injection of PC-3M prostate cancer cells were monitored with in vivo bioluminescence. Carbohydrates and dairy products’ buffering score varied between 0.5 and 19. Fruits and vegetables showed a low to zero buffering score. The score of meats varied between 6 and 22. Wine and juices had negative scores. Among supplements, sodium bicarbonate and Tums® had the highest buffering capacities, with scores of 11 and 20 per serving size, respectively. The “de-buffered” lysine had a less pronounced effect of prevention of metastases compared to lysine at pH 10. This study has demonstrated the anti-cancer effects of buffer therapy and suggests foods that can contribute to or compete with this approach to manage cancer. PMID:24371544

  19. Bicarbonate dialysate for continuous renal replacement therapy in intensive care unit patients with acute renal failure

    Microsoft Academic Search

    Martine Leblanc; Luz Moreno; Orlandus P. Robinson; Mihaly Tapolyai; Emil P. Paganini

    1995-01-01

    Lactate-buffered peritoneal solution traditionally has been used as dialysate for continuous renal replacement therapy (CRRT) in the United States because no bicarbonate solution is commercially available. Since 1994, the Cleveland Clinic Foundation Dialysis Unit has prepared a bicarbonate solution (sodium 144 ± 3 mEq\\/L, HCO3 37 ± 2 mEq\\/L, potassium 3 or 4 mEq\\/L, calcium 3.0 ± 0.3 mEq\\/L, and

  20. Buffer Combinations for Mammalian Cell Culture

    Microsoft Academic Search

    Harry Eagle

    1971-01-01

    The growth and metabolism of cultured mammalian cells are markedly affected by the pH variation in ordinary bicarbonate-buffered media(pH 8.0 to 6.9). Those pH swings can be reduced and the pH of the culture can be stabilized as desired in the range pH 6.4 to 8.3 by appropriate combinations of two or three organic buffers, each at 10 to 15

  1. 21 CFR 184.1736 - Sodium bicarbonate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... (a) Sodium bicarbonate (NaHCO3 , CAS Reg. No. 144-55-8) is prepared by treating a sodium carbonate or a sodium carbonate and sodium bicarbonate solution with carbon dioxide. As carbon dioxide is absorbed, a suspension of...

  2. 21 CFR 184.1736 - Sodium bicarbonate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... (a) Sodium bicarbonate (NaHCO3 , CAS Reg. No. 144-55-8) is prepared by treating a sodium carbonate or a sodium carbonate and sodium bicarbonate solution with carbon dioxide. As carbon dioxide is absorbed, a suspension of...

  3. 21 CFR 184.1736 - Sodium bicarbonate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... (a) Sodium bicarbonate (NaHCO3 , CAS Reg. No. 144-55-8) is prepared by treating a sodium carbonate or a sodium carbonate and sodium bicarbonate solution with carbon dioxide. As carbon dioxide is absorbed, a suspension of...

  4. 21 CFR 184.1736 - Sodium bicarbonate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... (a) Sodium bicarbonate (NaHCO3 , CAS Reg. No. 144-55-8) is prepared by treating a sodium carbonate or a sodium carbonate and sodium bicarbonate solution with carbon dioxide. As carbon dioxide is absorbed, a suspension of...

  5. 21 CFR 184.1736 - Sodium bicarbonate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... (a) Sodium bicarbonate (NaHCO3 , CAS Reg. No. 144-55-8) is prepared by treating a sodium carbonate or a sodium carbonate and sodium bicarbonate solution with carbon dioxide. As carbon dioxide is absorbed, a suspension of...

  6. Hemodialysis with acetate, DL-lactate and bicarbonate: A hemodynamic and gasometric study

    Microsoft Academic Search

    Jose A Herrero; Juan I Trobo; Jaime Torrente; Antonio Torralbo; Fernando Tornero; Antonio Cruceyra; Francisco Coronel; Alberto Barrientos

    1994-01-01

    Hemodialysis with acetate, DL-lactate and bicarbonate: A hemodynamic and gasometric study. Using invasive techniques we have studied various hemodynamic and gasometric parameters in the course of hemodialysis (HD) with different buffers in an animal model. HD sessions of 180 minutes at zero ultrafiltration were carried out on three groups of eight uremic dogs each, under anesthesia and constant mechanical ventilation.

  7. Effect of Dietary Sodium Bicarbonate and Magnesium Oxide on Production and Physiology in Early Lactation1

    Microsoft Academic Search

    R. A. Erdman; R. L. Botts; R. W. Hemken; L. S. Bull

    1980-01-01

    Twenty cows were in an experiment to measure effects of dietary buffers, sodium bicarbonate and magnesium oxide, on ration adjustment and incidence of metabolic problems in the first 8 wk postpartum. Cows were fed 2.7 kg grain per day and alfalfa ad libitum prepartum and switched immediately to a complete ration of 40% corn silage and 60% con- centrate (dry

  8. The duodenal mucosal bicarbonate secretion.

    PubMed

    Sjöblom, Markus

    2005-01-01

    The duodenal lumen is exposed to aggressive factors with a high potential to cause damage to the mucosa. Bicarbonate secretion by the duodenal mucosa is accepted as the primary important defense mechanism against the hydrochloric acid intermittently expelled from the stomach. The present work concerns both the influence of the central nervous system and the effects of the hormone melatonin on duodenal bicarbonate secretion in anesthetized rats in vivo as well as effects of melatonin on intracellular calcium signaling by duodenal enterocyte in vitro examined in tissues of both human and rat origin. The main findings were as follows: Melatonin is a potent stimulant of duodenal mucosal bicarbonate secretion and also seems to be involved in the acid-induced stimulation of the secretion. Stimulation elicited in the central nervous system by the alpha1-adrenoceptor agonist phenylephrine induced release of melatonin from the intestinal mucosa and a four-fold increase in alkaline secretion. The melatonin antagonist luzindole abolished the duodenal secretory response to administered melatonin and to central nervous phenylephrine but did not influence the release of intestinal melatonin. Central nervous stimulation was also abolished by synchronous ligation of the vagal trunks and the sympathetic chains at the sub-laryngeal level. Melatonin induced release of calcium from intracellular stores and also influx of extracellular calcium in isolated duodenal enterocytes. Enterocytes in clusters functioned as a syncytium. Overnight fasting rapidly and profoundly down-regulated the responses to the duodenal secretagogue orexin-A and the muscarinic agonist bethanechol but not those to melatonin or vasoactive intestinal polypeptide. PMID:16075893

  9. Physiological responses in swine treated with water containing sodium bicarbonate as a prophylactic for gastric ulcers1,2

    Microsoft Academic Search

    J. T. Cole; R. A. Argenzio; J. H. Eisemann

    Maintenance of gastric pH above 4.0 aids the prevention of bile acid-mediated ulcerative damage to the pars esophageal tissue in pigs. One means of doing so is the addition of buffering com- pounds, such as sodium bicarbonate, to the water sup- ply; however, any potential physiological effect of buffer consumption has yet to be determined. Experiment 1 tested the acute

  10. CELL BIOLOGY: A Universal Bicarbonate Sensor

    NSDL National Science Digital Library

    U. Benjamin Kaupp (Institut für Biologische Informationsverarbeitung; )

    2000-07-28

    Access to the article is free, however registration and sign-in are required. The three principal molecular events that prepare sperm for fertilization are all controlled by the intracellular nucleotide adenosine 3',5'-monophosphate (cAMP). One of these, capacitation, is also regulated by bicarbonate ions. The elusive connection between cAMP and bicarbonate ions now appears to be solved as Kaupp and Weyand explain in their Perspective. Bicarbonate ions enter sperm through the anion transporter in the sperm plasma membrane and activate the soluble form of adenylyl cyclase, the enzyme that synthesizes cAMP (Chen et al.)

  11. Effect of ranitidine on basal and bicarbonate enhanced intragastric PCO2: a tonometric study

    Microsoft Academic Search

    J J Kolkman; A B Groeneveld; S G Meuwissen

    1994-01-01

    A high intragastric PCO2 (iPCO2), determined tonometrically, is the main factor participating in a low gastric intramucosal pH (pHi) and may point to gastric mucosal ischaemia. iPCO2 might also increase, however, after buffering of gastric acid by bicarbonate; the magnitude of this effect and the efficacy of H2 blockers to prevent it are unclear. Ten healthy volunteers (20-24 years) were

  12. Buffer Biology.

    ERIC Educational Resources Information Center

    Morgan, Kelly

    2000-01-01

    Presents a science experiment in which students test the buffering capacity of household products such as shampoo, hand lotion, fizzies candy, and cola. Lists the standards addressed in this experiment and gives an example of a student lab write-up. (YDS)

  13. Native Small Airways Secrete Bicarbonate

    PubMed Central

    Quinton, Paul M.

    2014-01-01

    Since the discovery of Cl? impermeability in cystic fibrosis (CF) and the cloning of the responsible channel, CF pathology has been widely attributed to a defect in epithelial Cl? transport. However, loss of bicarbonate (HCO3?) transport also plays a major, possibly more critical role in CF pathogenesis. Even though HCO3? transport is severely affected in the native pancreas, liver, and intestines in CF, we know very little about HCO3? secretion in small airways, the principle site of morbidity in CF. We used a novel, mini-Ussing chamber system to investigate the properties of HCO3? transport in native porcine small airways (? 1 mm ?). We assayed HCO3? transport across small airway epithelia as reflected by the transepithelial voltage, conductance, and equivalent short-circuit current with bilateral 25-mM HCO3? plus 125-mM NaGlu Ringer’s solution in the presence of luminal amiloride (10 ?M). Under these conditions, because no major transportable anions other than HCO3? were present, we took the equivalent short-circuit current to be a direct measure of active HCO3? secretion. Applying selective agonists and inhibitors, we show constitutive HCO3? secretion in small airways, which can be stimulated significantly by ?-adrenergic– (cAMP) and purinergic (Ca2+) -mediated agonists, independently. These results indicate that two separate components for HCO3? secretion, likely via CFTR- and calcium-activated chloride channel–dependent processes, are physiologically regulated for likely roles in mucus clearance and antimicrobial innate defenses of small airways. PMID:24224935

  14. Bicarbonate stabilizes isolated D1/D2/cytochrome b559 complex of photosystem 2 against thermoinactivation.

    PubMed

    Pobeguts, O V; Smolova, T N; Klimov, V V

    2012-02-01

    It has been shown that thermoinactivation of the isolated D1/D2/cytochrome b(559) complex (RC) of photosystem 2 (PS-2) from pea under anaerobic conditions at 35°C in 20 mM Tris-HCl buffer (pH 7.2) depleted of HCO(3)(-), with 35 mM NaCl and 0.05% n-dodecyl-?-maltoside, results in a decrease in photochemical activity measured by photoreduction of the PS-2 primary electron acceptor, pheophytin (by 50% after 3 min of heating), which is accompanied by aggregation of the D1 and D2 proteins. Bicarbonate, formate, and acetate anions added to the sample under these conditions differently influence the maintenance of photochemical activity: a 50% loss of photochemical activity occurs in 11.5 min of heating in the presence of bicarbonate and in 4 and 4.6 min in the presence of formate and acetate, respectively. The addition of bicarbonate completely prevents aggregation of the D1 and D2 proteins as opposed to formate and acetate (their presence has no effect on the aggregation during thermoinactivation). Since the isolated RCs have neither inorganic Mn/Ca-containing core of the water-oxidizing complex nor nonheme Fe(2+), it is supposed that bicarbonate specifically interacts with the hydrophilic domains of the D1 and D2 proteins, which prevents their structural modification that is a signal for aggregation of these proteins and the loss of photochemical activity. PMID:22348477

  15. 40 CFR 415.140 - Applicability; description of the sodium bicarbonate production subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...Applicability; description of the sodium bicarbonate production subcategory. ...MANUFACTURING POINT SOURCE CATEGORY Sodium Bicarbonate Production Subcategory ...Applicability; description of the sodium bicarbonate production...

  16. 40 CFR 415.140 - Applicability; description of the sodium bicarbonate production subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Applicability; description of the sodium bicarbonate production subcategory. ...MANUFACTURING POINT SOURCE CATEGORY Sodium Bicarbonate Production Subcategory ...Applicability; description of the sodium bicarbonate production...

  17. 40 CFR 415.140 - Applicability; description of the sodium bicarbonate production subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Applicability; description of the sodium bicarbonate production subcategory. ...MANUFACTURING POINT SOURCE CATEGORY Sodium Bicarbonate Production Subcategory ...Applicability; description of the sodium bicarbonate production...

  18. 40 CFR 415.140 - Applicability; description of the sodium bicarbonate production subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...Applicability; description of the sodium bicarbonate production subcategory. ...MANUFACTURING POINT SOURCE CATEGORY Sodium Bicarbonate Production Subcategory ...Applicability; description of the sodium bicarbonate production...

  19. 40 CFR 415.140 - Applicability; description of the sodium bicarbonate production subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...Applicability; description of the sodium bicarbonate production subcategory. ...MANUFACTURING POINT SOURCE CATEGORY Sodium Bicarbonate Production Subcategory ...Applicability; description of the sodium bicarbonate production...

  20. Seasonal, reproductive, and nutritional influences on muscle “buffering capacity” in yellow perch ( Perca flavescens )

    Microsoft Academic Search

    Jay A. Nelson; John J. Magnuson

    1987-01-01

    “Effective non-bicarbonatebuffering capacity (or buffer value) was measured in white muscle of yellow perch (Perca flavescens) by titrations with mineral acid and base in a carbon-dioxide free, closed system. Yellow perch were collected at three month intervals throughout 1983 from an acidic lake (pH ? 4.6) and two alkaline lakes (pH ? 7.8) in northern Wisconsin. “Buffering capacity” was

  1. Bicarbonate and bicarbonate/lactate peritoneal dialysis solutions for the treatment of infusion pain.

    PubMed

    Mactier, R A; Sprosen, T S; Gokal, R; Williams, P F; Lindbergh, M; Naik, R B; Wrege, U; Gröntoft, K C; Larsson, R; Berglund, J; Tranaeus, A P; Faict, D

    1998-04-01

    A randomized, double-blind, cross-over study was undertaken to determine the effects of novel bicarbonate (38 mM) and bicarbonate (25 mM)/lactate (15 mM) containing peritoneal dialysis (PD) solutions on infusion pain in patients who experienced inflow pain with conventional lactate (40 mM) solution. Pain was assessed using a verbal rating scale and the validated McGill Pain Questionnaire (MPQ). Eighteen patients were recruited to the study. Both novel solutions resulted in highly statistically significant reductions in inflow pain compared to the control lactate solution, as assessed with both the verbal rating scale and the MPQ. For all pain variables assessed, the bicarbonate/lactate solution was more effective than the bicarbonate solution in alleviating pain. In conclusion, both solutions reduced the infusion pain experienced with control solution, but the bicarbonate/lactate solution appears to be the most effective. In contrast to the most widespread current treatment, which is the manual injection of sodium bicarbonate, the bicarbonate/lactate solution does not have the associated increased risk of peritonitis. PMID:9551418

  2. Sodium bicarbonate in chemical flooding: Part 1: Topical report. [Sodium bicarbonate and sodium carbonate

    SciTech Connect

    Peru, D.A.; Lorenz, P.B.

    1987-07-01

    To compare oil recovery and alkali consumption in alkaline flooding using sodium bicarbonate with other alkaline agents, coreflooding experiments were performed in turn with viscosified sodium bicarbonate and viscosified sodium carbonate solutions. Oil recovery was monitored, and the effluent brine from these corefloods was analyzed for silicon, aluminum, pH, and total inorganic carbon. The results indicate that viscosified sodium bicarbonate recovered more of the asphaltic Cerro-Negro crude than of the less asphaltic Wilmington crude oil. The recovery efficiency using the viscosified sodium carbonate was similar for the two crudes. For both crudes, the percent oil recovery using viscosified sodium carbonate was slightly higher than that using the viscosified sodium bicarbonate. Mineral dissolution and decrease in pH were found to be greater in corefloods using viscosified sodium carbonate. Total inorganic carbon recovery can be obtained in corefloods with either agent, provided that a sufficient water drive follows the chemical slug. Long-term experiments were performed by recirculating alkaline solutions through oil-free, unfired Berea sandstone to monitor the rock/alkali interactions. The experimental results indicate an eight-fold decrease in quartz dissolution by sodium bicarbonate compared with sodium carbonate. Moderate magnesium solubility was observed at the pH of the bicarbonate solution. Low solubility of magnesium and aluminum at the pH of the carbonate indicates the possible formation of precipitates. In these experiments 13% of the carbonate was converted to bicarbonate. Total alkalinity was not significantly decreased with either agent. 18 refs., 5 tabs.

  3. Sodium-Bicarbonate Cotransport in Retinal Astrocytes and Mu ller

    E-print Network

    Newman, Eric A.

    Sodium-Bicarbonate Cotransport in Retinal Astrocytes and Mu¨ ller Cells of the Rat ERIC A. NEWMANH; imaging; BCPCF; pH regulation ABSTRACT Sodium-bicarbonate cotransport in retinal glial cells was studied

  4. ORIGINAL RESEARCH Systematic family-wide analysis of sodium bicarbonate

    E-print Network

    Hall, Randy A

    ORIGINAL RESEARCH Systematic family-wide analysis of sodium bicarbonate cotransporter NBCn1/SLC4A7, Atlanta, Georgia, USA Keywords Bicarbonate transporter, pH, protein interaction, SLC4A7, Xenopus oocyte proteins. Introduction NBCn1 (SLC4A7) is a member of SLC4 bicarbonate transporters that include Cl/HCO3

  5. FATE OF INGESTED SODIUM BICARBONATE IN THE FOWL

    E-print Network

    Paris-Sud XI, Université de

    FATE OF INGESTED SODIUM BICARBONATE IN THE FOWL J.-R. HUNT Canada Department of Agriculture (1) and HowEs (1967), that the incorporation of sodium bicarbonate in the diet of the hen results!RPO>&dquo; 1966) and would be unfavourable for sodium bicarbonate to exist in the ionic form. From the results

  6. Overcoming ammonium toxicity.

    PubMed

    Bittsánszky, András; Pilinszky, Katalin; Gyulai, Gábor; Komives, Tamas

    2015-02-01

    Ammonia (ammonium ion under physiological conditions) is one of the key nitrogen sources in cellular amino acid biosynthesis. It is continuously produced in living organisms by a number of biochemical processes, but its accumulation in cells leads to tissue damage. Current knowledge suggests that a few enzymes and transporters are responsible for maintaining the delicate balance of ammonium fluxes in plant tissues. In this study we analyze the data in the scientific literature and the publicly available information on the dozens of biochemical reactions in which endogenous ammonium is produced or consumed, the enzymes that catalyze them, and the enzyme and transporter mutants listed in plant metabolic and genetic databases (Plant Metabolic Network, TAIR, and Genevestigator). Our compiled data show a surprisingly high number of little-studied reactions that might influence cellular ammonium concentrations. The role of ammonium in apoptosis, its relation to oxidative stress, and alterations in ammonium metabolism induced by environmental stress need to be explored in order to develop methods to manage ammonium toxicity. PMID:25576003

  7. Seawater bicarbonate removal during hydrothermal circulation

    NASA Astrophysics Data System (ADS)

    Proskurowski, G. K.; Seewald, J.; Sylva, S. P.; Reeves, E.; Lilley, M. D.

    2013-12-01

    High temperature fluids sampled at hydrothermal vents represent a complex alteration product of water-rock reactions on a multi-component mixture of source fluids. Sources to high-temperature hydrothermal samples include the 'original' seawater present in the recharge limb of circulation, magmatically influenced fluids added at depth as well as any seawater entrained during sampling. High-temperature hydrothermal fluids are typically enriched in magmatic volatiles, with CO2 the dominant species, characterized by concentrations of 10's-100's of mmol/kg (1, 2). Typically, the high concentration of CO2 relative to background seawater bicarbonate concentrations (~2.3 mmol/kg) obscures a full analysis of the fate of seawater bicarbonate during high-temperature hydrothermal circulation. Here we present data from a suite of samples collected over the past 15 years from high-temperature hydrothermal vents at 9N, Endeavour, Lau Basin, and the MAR that have endmember CO2 concentrations less than 10 mmol/kg. Using stable and radiocarbon isotope measurements these samples provide a unique opportunity to examine the balance between 'original' seawater bicarbonate and CO2 added from magmatic sources. Multiple lines of evidence from multiple hydrothermal settings consistently points to the removal of ~80% of the 'original' 2.3 mmol/kg seawater bicarbonate. Assuming that this removal occurs in the low-temperature, 'recharge' limb of hydrothermal circulation, this removal process is widely occurring and has important contributions to the global carbon cycle over geologic time. 1. Lilley MD, Butterfield DA, Lupton JE, & Olson EJ (2003) Magmatic events can produce rapid changes in hydrothermal vent chemistry. Nature 422(6934):878-881. 2. Seewald J, Cruse A, & Saccocia P (2003) Aqueous volatiles in hydrothermal fluids from the Main Endeavour Field, northern Juan de Fuca Ridge: temporal variability following earthquake activity. Earth and Planetary Science Letters 216(4):575-590.

  8. Comparison of in vitro AGE formation between standard PD fluid and a novel bicarbonate/lactate formulation.

    PubMed

    Millar, D J; Holmes, C; Faict, D; Dawnay, A

    1998-01-01

    Peritoneal advanced glycation end-product (AGE) formation may be accelerated by glucose degradation products produced as a consequence of heat sterilization of peritoneal dialysis (PD) fluid. The formation of these degradation products is reduced if the glucose is separated from the buffers during heat sterilization. This pilot study compared in vitro AGE formation in PD fluid (1.36% and 3.86% glucose) heat sterilized in a two-compartment bag (bicarbonate/lactate buffer) with that in a standard, single-compartment bag (lactate buffer, Dianeal). Peritoneal dialysis fluids were incubated with human serum albumin (HSA, 1 g/L), as a model protein, at 37 degrees C for 0, 5, and 20 days. Formation of AGEs was assessed by measuring fluorescence at each time point. Advanced glycation end-product formation was greater in lactate PD fluid compared with bicarbonate/lactate PD fluid of equivalent glucose strength. Advanced glycation end-product formation in the lactate PD fluid containing 1.36% glucose was comparable to that in the bicarbonate/lactate PD fluid containing 3.86% glucose. The rate of increase in fluorescence per day was greater in the first 5 days of incubation than in the subsequent 15 days. These results are compatible with the presence of greater amounts of glucose-degradation products in the standard single-compartment bag resulting in enhanced AGE formation. PMID:10649722

  9. CHLORIDEDETERMINATION IN HIGH IONIC STRENGTH SOLUTION OF AMMONIUM ACETATE USING NEGATIVE ION ELECTRON SPRAY IONIZATION (HPLC/MS)

    EPA Science Inventory

    A precise ion chromatography method has been developed for the determination of chloride in high ionic strength ammonium acetate solutions (10-5 M-5 M) using sodium carbonate/sodium bicarbonate as eluent. Negative ion electrospray ionization (ESI) mass spectrometry was used for q...

  10. Sodium Is Not Required for Chloride Efflux via Chloride/Bicarbonate Exchanger from Rat Thymic Lymphocytes

    PubMed Central

    Stakišaitis, Donatas; Meilus, Vaidevutis; Juška, Alfonsas; Matusevi?ius, Paulius; Didžiapetrien?, Janina

    2014-01-01

    Sodium-dependent Cl?/HCO3? exchanger acts as a chloride (Cl?) efflux in lymphocytes. Its functional characterization had been described when Cl? efflux was measured upon substituting extracellular sodium (Na+) by N-methyl-D-glucamine (NMDG). For Na+ and Cl? substitution, we have used D-mannitol or NMDG. Thymocytes of male Wistar rats aged 7–9 weeks were used and intracellular Cl? was measured by spectrofluorimetry using MQAE dye in bicarbonate buffers. Chloride efflux was measured in a Cl?-free buffer (Cl? substituted with isethionate acid) and in Na+ and Cl?-free buffer with D-mannitol or with NMDG. The data have shown that Cl? efflux is mediated in the absence of Na+ in a solution containing D-mannitol and is inhibited by H2DIDS. Mathematical modelling has shown that Cl? efflux mathematical model parameters (relative membrane permeability, relative rate of exchanger transition, and exchanger efficacy) were the same in control and in the medium in which Na+ had been substituted by D-mannitol. The net Cl? efflux was completely blocked in the NMDG buffer. The same blockage of Cl? efflux was caused by H2DIDS. The study results allow concluding that Na+ is not required for Cl? efflux via Cl?/HCO3? exchanger. NMDG in buffers cannot be used for substituting Na+ because NMDG inhibits the exchanger. PMID:25003116

  11. Molecular Structure of Ammonium ion

    NSDL National Science Digital Library

    2002-09-10

    The first widespread production of ammonium compounds occurred during the 1890s when ammonium sulfate was produced as a by-product from coke oven gas. Ammonium ion is produced as a product of the reaction of water and ammonia. Often, ammonium salts are isomorphous. They have a similar solubility to potassium and rubidium salts, whose ions are similar in size to ammonium. The ion is most stable in the presence of a large compound with a single negative charge.

  12. Infrared band intensities in ammonium hydroxide and ammonium salts

    NASA Technical Reports Server (NTRS)

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

    1978-01-01

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

  13. Soluble Adenylyl Cyclase as an Evolutionarily Conserved Bicarbonate Sensor

    Microsoft Academic Search

    Yanqiu Chen; Martin J. Cann; Tatiana N. Litvin; Vadim Iourgenko; Meeghan L. Sinclair; Lonny R. Levin; Jochen Buck

    2000-01-01

    Spermatozoa undergo a poorly understood activation process induced by bicarbonate and mediated by cyclic adenosine 3',5'-monophosphate (cAMP). It has been assumed that bicarbonate mediates its effects through changes in intracellular pH or membrane potential; however, we demonstrate here that bicarbonate directly stimulates mammalian soluble adenylyl cyclase (sAC) activity in vivo and in vitro in a pH-independent manner. sAC is most

  14. Electroantennogram and behavioral responses of Anastrepha suspensa (Diptera: Tephritidae) to putrescine and ammonium bicarbonate lures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    At present, the most effective synthetic lures for pest Anastrepha fruit flies are multi-component blends that include an ammonia-emitting substrate and the diamine synergist, putrescine (1,4-diaminobutane). Both chemicals are regarded as protein-feeding cues which result in female-biased attractio...

  15. Honeycomb-like graphitic ordered macroporous carbon prepared by pyrolysis of ammonium bicarbonate

    SciTech Connect

    Wang, Liancheng [Key Laboratory of Colloid and Interface Chemistry, Shandong University, Jinan, Shandong 250100 (China)] [Key Laboratory of Colloid and Interface Chemistry, Shandong University, Jinan, Shandong 250100 (China); Zhang, Junhao, E-mail: jhzhang6@mail.ustc.edu.cn [Key Laboratory of Colloid and Interface Chemistry, Shandong University, Jinan, Shandong 250100 (China) [Key Laboratory of Colloid and Interface Chemistry, Shandong University, Jinan, Shandong 250100 (China); School of Biology and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu 212003 (China); Xu, Liqiang; Qian, Yitai [Key Laboratory of Colloid and Interface Chemistry, Shandong University, Jinan, Shandong 250100 (China)] [Key Laboratory of Colloid and Interface Chemistry, Shandong University, Jinan, Shandong 250100 (China)

    2011-10-15

    Graphical abstract: Honeycomb-like graphitic macroporous carbon (HGMC) with big pores centered at 1-3 {mu}m, has been prepared by controlling the reaction temperature and amount of NH{sub 4}HCO{sub 3} at 550 {sup o}C in a sealed reaction system. Possible formation processes of HGMC are discussed on the experimental results. It is believed that the in situ formed MgO microparticles play a template role during the preparation of HGMC. Highlights: {yields} Honeycomb-like graphitic carbon was synthesized at 550 {sup o}C. {yields} The honeycomb-like graphitic carbon is macroposous structures. {yields} The formed MgO microparticles play a template role during the HGMC formation. {yields} The method can be expended to synthesize other porous or hollow carbon material. -- Abstract: Honeycomb-like graphitic macroporous carbon (HGMC) was synthesized by means of pyrolysis of NH{sub 4}HCO{sub 3} using Mg powder as reductant in an autoclave at 550 {sup o}C. The characterization of structure and morphology was carried out by X-ray diffraction (XRD), Raman spectrum, field-emission scanning electron microscopy (FESEM), and (High-resolution) transmission electron microscope [(HR)TEM]. The results of nitrogen adsorption-desorption indicate that the products are macropore materials with the pore size of 1-3 {mu}m, and the Brunauer-Emett-Teller (BET) surface area was 14 m{sup 2}/g. As a typical morphology, the possible growth process of HGMC was also investigated and discussed. The experimental results show that the in situ formed MgO microparticles play a template role during the HGMC formation.

  16. Studies on chemical bath deposited cadmium sulphide films by buffer solution technique

    Microsoft Academic Search

    N. G. Dhere; D. L. Waterhouse; K. B. Sundaram; O. Melendez; N. R. Parikh; B. Patnaik

    1995-01-01

    Cadmium sulphide films were grown by a chemical bath technique using cadmium acetate and cadmium chloride as the Cd ion source and thiourea as the sulphur source. The solution growth process was carried out with and without buffer solutions containing ammonium acetate and ammonium chloride onto glass substrates. Various properties of the films such as surface morphology, crystallinity, composition, optical

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

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

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

  18. Mechanisms of Contrast-Induced Nephropathy Reduction for Saline (NaCl) and Sodium Bicarbonate (NaHCO3)

    PubMed Central

    Burgess, W. Patrick; Walker, Phillip J.

    2014-01-01

    Nephropathy following contrast media (CM) exposure is reduced by administration before, during, and after the contrast procedure of either isotonic sodium chloride solution (Saline) or isotonic sodium bicarbonate solution (IsoBicarb). The reasons for this reduction are not well established for either sodium salt; probable mechanisms are discussed in this paper. For Saline, the mechanism for the decrease in CIN is likely related primarily to the increased tubular flow rates produced by volume expansion and therefore a decreased concentration of the filtered CM during transit through the kidney tubules. Furthermore, increased tubular flow rates produce a slight increase in tubular pH resulting from a fixed acid excretion in an increased tubular volume. The mechanism for the decreased CIN associated with sodium bicarbonate includes the same mechanisms listed for Saline in addition to a renal pH effect. Increased filtered bicarbonate anion raises both tubular pH and tubular bicarbonate anion levels toward blood physiologic levels, thus providing increased buffer for reactive oxygen species (ROS) formed in the tubules as a result of exposure to CM in renal tubular fluid. PMID:24826379

  19. Mechanisms of contrast-induced nephropathy reduction for saline (NaCl) and sodium bicarbonate (NaHCO3).

    PubMed

    Burgess, W Patrick; Walker, Phillip J

    2014-01-01

    Nephropathy following contrast media (CM) exposure is reduced by administration before, during, and after the contrast procedure of either isotonic sodium chloride solution (Saline) or isotonic sodium bicarbonate solution (IsoBicarb). The reasons for this reduction are not well established for either sodium salt; probable mechanisms are discussed in this paper. For Saline, the mechanism for the decrease in CIN is likely related primarily to the increased tubular flow rates produced by volume expansion and therefore a decreased concentration of the filtered CM during transit through the kidney tubules. Furthermore, increased tubular flow rates produce a slight increase in tubular pH resulting from a fixed acid excretion in an increased tubular volume. The mechanism for the decreased CIN associated with sodium bicarbonate includes the same mechanisms listed for Saline in addition to a renal pH effect. Increased filtered bicarbonate anion raises both tubular pH and tubular bicarbonate anion levels toward blood physiologic levels, thus providing increased buffer for reactive oxygen species (ROS) formed in the tubules as a result of exposure to CM in renal tubular fluid. PMID:24826379

  20. Purification of Ammonium Alum

    Microsoft Academic Search

    G. Dillon; A. Armington

    1962-01-01

    IGH-purity ammonium alum is of interest in the magnetics field as a starting compound in the preparation of aluminum oxide for use as a matrix material in synthetic crystals. The authors investi­ gated several purification procedures in an attempt to improve the purity of presently available alums; zone refining of hydrated alum, recrystallization, and sol­ vent extraction. Zone-refining experiments were

  1. EFFECT OF BUFFERED AND UNBUFFERED TRICAINE METHANESULFONATE (MS-222) AT DIFFERENT CONCENTRATIONS ON THE STRESS RESPONSES OF CHANNEL CATFISH (ICTALURUS PUNCTATUS RAFINESQUE)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of four concentrations (0, 90, 120, and 180 mg/L) of the anesthetic tricaine methanesulfonate (MS-222) (buffered and unbuffered with sodium bicarbonate) were evaluated on anesthetization efficacy and stress responses of juvenile channel catfish (Ictalurus punctatus Rafinesque). Buffered ...

  2. SIMULTANEOUS TITRIMETRIC DETERMINATION OF BICARBONATE AND TITRATABLE ACID OF URINE

    Microsoft Academic Search

    AZ Györy; KDG Edwards

    1967-01-01

    An acid-titration method for the determination of bicarbonate and titratable acid in the one sample of urine is described. The method needs only one manipulation of the sample of urine, and was devised to simplify routine laboratory methodology. The accuracy and precision of the urinary bicarbonate method during routine laboratory use is comparable to that obtained by using the Van

  3. 46 CFR 148.205 - Ammonium nitrate and ammonium nitrate fertilizers.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...Ammonium nitrate and ammonium nitrate fertilizers. 148.205 Section 148.205 ...Ammonium nitrate and ammonium nitrate fertilizers. (a) This section applies to...of ammonium nitrate and the following fertilizers composed of uniform,...

  4. 46 CFR 148.205 - Ammonium nitrate and ammonium nitrate fertilizers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...Ammonium nitrate and ammonium nitrate fertilizers. 148.205 Section 148.205 ...Ammonium nitrate and ammonium nitrate fertilizers. (a) This section applies to...of ammonium nitrate and the following fertilizers composed of uniform,...

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

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...Ammonium nitrate and ammonium nitrate fertilizers. 148.205 Section 148.205 ...Ammonium nitrate and ammonium nitrate fertilizers. (a) This section applies to...of ammonium nitrate and the following fertilizers composed of uniform,...

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

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...Ammonium nitrate and ammonium nitrate fertilizers. 148.205 Section 148.205 ...Ammonium nitrate and ammonium nitrate fertilizers. (a) This section applies to...of ammonium nitrate and the following fertilizers composed of uniform,...

  7. 4, 29492971, 2004 Ammonium sulfate

    E-print Network

    Paris-Sud XI, Université de

    ACPD 4, 2949­2971, 2004 Ammonium sulfate ­ malonic acid aerosols C. F. Braban and J. P. D. Abbatt and Physics Discussions A study of the phase transition behavior of mixed ammonium sulfate ­ malonic acid Ammonium sulfate ­ malonic acid aerosols C. F. Braban and J. P. D. Abbatt Title Page Abstract Introduction

  8. 40 CFR 180.1177 - Potassium bicarbonate; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 2011-07-01 false Potassium bicarbonate; exemption from the requirement...Exemptions From Tolerances § 180.1177 Potassium bicarbonate; exemption from the requirement...tolerance. The biochemical pesticide potassium bicarbonate is exempted from...

  9. 40 CFR 180.1176 - Sodium bicarbonate; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 2011-07-01 false Sodium bicarbonate; exemption from the requirement...Tolerances § 180.1176 Sodium bicarbonate; exemption from the requirement... The biochemical pesticide sodium bicarbonate is exempted from the...

  10. 40 CFR 180.1176 - Sodium bicarbonate; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 2010-07-01 false Sodium bicarbonate; exemption from the requirement...Tolerances § 180.1176 Sodium bicarbonate; exemption from the requirement... The biochemical pesticide sodium bicarbonate is exempted from the...

  11. 40 CFR 180.1176 - Sodium bicarbonate; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 2012-07-01 false Sodium bicarbonate; exemption from the requirement...Tolerances § 180.1176 Sodium bicarbonate; exemption from the requirement... The biochemical pesticide sodium bicarbonate is exempted from the...

  12. 40 CFR 180.1176 - Sodium bicarbonate; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 2014-07-01 false Sodium bicarbonate; exemption from the requirement...Tolerances § 180.1176 Sodium bicarbonate; exemption from the requirement... The biochemical pesticide sodium bicarbonate is exempted from the...

  13. 40 CFR 180.1176 - Sodium bicarbonate; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 2013-07-01 false Sodium bicarbonate; exemption from the requirement...Tolerances § 180.1176 Sodium bicarbonate; exemption from the requirement... The biochemical pesticide sodium bicarbonate is exempted from the...

  14. 21 CFR 862.1160 - Bicarbonate/carbon dioxide test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 false Bicarbonate/carbon dioxide test system. 862.1160 Section... § 862.1160 Bicarbonate/carbon dioxide test system. (a) Identification. A bicarbonate/carbon dioxide test system is a device...

  15. 21 CFR 862.1160 - Bicarbonate/carbon dioxide test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 false Bicarbonate/carbon dioxide test system. 862.1160 Section... § 862.1160 Bicarbonate/carbon dioxide test system. (a) Identification. A bicarbonate/carbon dioxide test system is a device...

  16. 21 CFR 862.1160 - Bicarbonate/carbon dioxide test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 false Bicarbonate/carbon dioxide test system. 862.1160 Section... § 862.1160 Bicarbonate/carbon dioxide test system. (a) Identification. A bicarbonate/carbon dioxide test system is a device...

  17. 21 CFR 862.1160 - Bicarbonate/carbon dioxide test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 false Bicarbonate/carbon dioxide test system. 862.1160 Section... § 862.1160 Bicarbonate/carbon dioxide test system. (a) Identification. A bicarbonate/carbon dioxide test system is a device...

  18. 21 CFR 862.1160 - Bicarbonate/carbon dioxide test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 false Bicarbonate/carbon dioxide test system. 862.1160 Section... § 862.1160 Bicarbonate/carbon dioxide test system. (a) Identification. A bicarbonate/carbon dioxide test system is a device...

  19. 40 CFR 180.1177 - Potassium bicarbonate; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 2010-07-01 false Potassium bicarbonate; exemption from the requirement...Exemptions From Tolerances § 180.1177 Potassium bicarbonate; exemption from the requirement...tolerance. The biochemical pesticide potassium bicarbonate is exempted from...

  20. Enhancement of the absorption of CO{sub 2} in alkaline buffer solutions: Joint action of two enhancers

    SciTech Connect

    Vazquez, G.; Chenlo, F.; Pereira, G.; Vazquez, P. [Univ. of Santiago de Compostela (Spain). Dept. of Chemical Engineering] [Univ. of Santiago de Compostela (Spain). Dept. of Chemical Engineering

    1999-05-01

    The authors measured the absorption of CO{sub 2} in alkaline 0.5 M/0.5 M sodium carbonate/bicarbonate buffers containing either saccharose and sodium arsenite or saccharose and formaldehyde. Absorption enhancement increased upon increasing the concentration of either of the catalysts, but the joint action of the two was always less than the sum of their individual effects, the difference being a function of the acidities and concentrations of the catalysts and the pH of the carbonate/bicarbonate buffer solution

  1. On the mechanisms responsible for the phosphaturia of bicarbonate administration.

    PubMed

    Mercado, A; Slatopolsky, E; Klahr, S

    1975-12-01

    Experiments were carried out in normal dogs to characterize the mechanisms by which sodium bicarbonate administration results in increased excretion of phosphate. Infusion of sodium bicarbonate alone increased fractional phosphate excretion from 0.8 to 29.3%. During bicarbonate administration, ionized calcium fell and mean parathyroid hormone values increased from 59.6 to 230.4 muleq/ml. In the same group of dogs, administration of sodium bicarbonate plus calcium prevented the fall in ionized calcium, and parathyroid hormone levels remained unchanged. In these dogs fractional phosphate excretion increased from 2.4 to only 4.9%. Similar results were obtained in thyroparathyroidectomized dogs receiving sodium bicarbonate. In these dogs fractional excretion of phosphate increased from 0.6 to 4.5%. Under all three experimental conditions no differences were observed in sodium or bicarbonate excretion or in urinary or plasma pH. Administration of hydrochloric acid, after phosphaturia had been induced by the infusion of bicarbonate, resulted in a decrease in plasma bicarbonate and an acid urine; however, the phosphaturia persisted even in the presence of an acid urine pH. In five thyroparathyroidectomized dogs infused with parathyroid hormone throughout, administration of identical amounts of sodium as either NaCl or NaHCO3 resulted in a similar degree of phosphaturia despite significant differences in urine pH. These experiments suggest that a rise in parathyroid hormone levels, resulting from a fall in ionized calcium, is the major mechanism by which bicarbonate administration produces phosphaturia. An increased natriuresis per nephron, as a consequence of extracellular fluid volume expansion, contributes to the phosphaturia. On the other hand, alkalinization of the urine does not play a significant role in the phosphaturia seen after bicarbonate administration. PMID:172529

  2. Potassium bicarbonate, but not sodium bicarbonate, reduces urinary calcium excretion and improves calcium balance in healthy men

    Microsoft Academic Search

    Jacob Lemann; Richard W Gray; Joan A Pleuss

    1989-01-01

    Potassium bicarbonate, but not sodium bicarbonate, reduces urinary calcium excretion and improves calcium balance in healthy men. Previous studies demonstrated that the administration of NaHCO3 or sodium citrate had either only a small effect to reduce urinary Ca excretion or no effect, but that potassium citrate significantly reduced urinary Ca excretion. In order to further evaluate and compare the effects

  3. VIRTUAL FRAME BUFFER INTERFACE

    NASA Technical Reports Server (NTRS)

    Wolfe, T. L.

    1994-01-01

    Large image processing systems use multiple frame buffers with differing architectures and vendor supplied user interfaces. This variety of architectures and interfaces creates software development, maintenance, and portability problems for application programs. The Virtual Frame Buffer Interface program makes all frame buffers appear as a generic frame buffer with a specified set of characteristics, allowing programmers to write code which will run unmodified on all supported hardware. The Virtual Frame Buffer Interface converts generic commands to actual device commands. The virtual frame buffer consists of a definition of capabilities and FORTRAN subroutines that are called by application programs. The virtual frame buffer routines may be treated as subroutines, logical functions, or integer functions by the application program. Routines are included that allocate and manage hardware resources such as frame buffers, monitors, video switches, trackballs, tablets and joysticks; access image memory planes; and perform alphanumeric font or text generation. The subroutines for the various "real" frame buffers are in separate VAX/VMS shared libraries allowing modification, correction or enhancement of the virtual interface without affecting application programs. The Virtual Frame Buffer Interface program was developed in FORTRAN 77 for a DEC VAX 11/780 or a DEC VAX 11/750 under VMS 4.X. It supports ADAGE IK3000, DEANZA IP8500, Low Resolution RAMTEK 9460, and High Resolution RAMTEK 9460 Frame Buffers. It has a central memory requirement of approximately 150K. This program was developed in 1985.

  4. Riparian Buffers for Wildlife Benefits of Riparian Buffers

    E-print Network

    Boyer, Elizabeth W.

    Riparian Buffers for Wildlife Benefits of Riparian Buffers Riparian buffers offer many benefits the buffer, the more likely it is to yield positive benefits. A riparian buffer: Traps sediment. Runoff from, which depletes oxygen levels. A good riparian buffer can remove up to 80 percent of excessive nutrient

  5. Bicarbonate sulfate exchange in canalicular rat liver plasma membrane vesicles

    SciTech Connect

    Meier, P.J.; Valantinas, J.; Hugentobler, G.; Rahm, I. (University Hospital, Zurich (Switzerland))

    1987-10-01

    The mechanism(s) and driving forces for biliary excretion of sulfate were investigated in canalicular rat liver plasma membrane vesicles (cLPM). Incubation of cLPM vesicles in the presence of an inside-to-outside (in, out) bicarbonate gradient but not pH or out-to-in sodium gradients, stimulated sulfate uptake 10-fold compared with the absence of bicarbonate and approximately 2-fold above sulfate equilibrium (overshoot). Initial rates of this bicarbonate gradient-driven ({sup 35}S)-sulfate uptake were saturable with increasing concentrations of sulfate and could be inhibited by probenecid, N-(4-azido-2-nitrophenyl)-2-aminoethylsulfonate, acetazolamide, furosemide, 4-acetamideo-4{prime}-isothiocyanostilbene-2,2{prime}-disulfonic acid, and 4,4{prime}-diisothiocyanostilbene-2,2{prime}-disulfonic acid (IC{sub 50}, {approximately}40 {mu}M). Cisinhibition of initial bicarbonate gradient-stimulated sulfate uptake and transstimulation of sulfate uptake in the absence of bicarbonate were observed with sulfate, thiosulfate, and oxalate but not with chloride, nitrate, phosphate, acetate, lactate, glutamate, aspartate, cholate, taurocholate, dehydrocholate, taurodehydrocholate, and reduced or oxidized glutathione. These findings indicate the presence of a sulfate (oxalate)-bicarbonate anion exchange system in canalicular rat liver plasma membranes. These findings support the concept that bicarbonate-sensitive transport system might play an important role in bile acid-independent canalicular bile formation.

  6. Cost-effective bioregeneration of nitrate-laden ion exchange brine through deliberate bicarbonate incorporation.

    PubMed

    Li, Qi; Huang, Bin; Chen, Xin; Shi, Yi

    2015-05-15

    Bioregeneration of nitrate-laden ion exchange brine is desired to minimize its environmental impacts, but faces common challenges, i.e., enriching sufficient salt-tolerant denitrifying bacteria and stabilizing brine salinity and alkalinity for stable brine biotreatment and economically removing undesired organics derived in biotreatment. Incorporation of 0.25 M bicarbonate in 0.5 M chloride brine little affected resin regeneration but created a benign alkaline condition to favor bio-based brine regeneration. The first-quarter sulfate-mainly enriched spent brine (SB) was acidified with carbon source acetic acid for using CaCl2 at an efficiency >80% to remove sulfate. Residual Ca(2+) was limited below 2 mM by re-mixing the first-quarter and remained SB to favor denitrification. Under [Formula: see text] system buffered pH condition (8.3-8.8), nitrate was removed at 0.90 gN/L/d by hematite-enriched well-settled activated sludge (SVI 8.5 ml/g) and the biogenic alkalinity was retained as bicarbonate. The biogenic alkalinity met the need of alkalinity in removing residual Ca(2+) after sulfate removal and in CaCl2-induced CaCO3 flocculation to remove 63% of soluble organic carbon (SOC) in biotreated brine. Carbon-limited denitrification was also operated after activated sludge acclimation with sulfide to cut SOC formation during denitrification. Overall, this bicarbonate-incorporation approach, stabilizing the brine salinity and alkalinity for stable denitrification and economical removal of undesired SOC, suits long-term cost-effective brine bioregeneration. PMID:25746960

  7. Bile Acids and Bicarbonate Inversely Regulate Intracellular Cyclic di-GMP in Vibrio cholerae

    PubMed Central

    Koestler, Benjamin J.

    2014-01-01

    Vibrio cholerae is a Gram-negative bacterium that persists in aquatic reservoirs and causes the diarrheal disease cholera upon entry into a human host. V. cholerae employs the second messenger molecule 3?,5?-cyclic diguanylic acid (c-di-GMP) to transition between these two distinct lifestyles. c-di-GMP is synthesized by diguanylate cyclase (DGC) enzymes and hydrolyzed by phosphodiesterase (PDE) enzymes. Bacteria typically encode many different DGCs and PDEs within their genomes. Presumably, each enzyme senses and responds to cognate environmental cues by alteration of enzymatic activity. c-di-GMP represses the expression of virulence factors in V. cholerae, and it is predicted that the intracellular concentration of c-di-GMP is low during infection. Contrary to this model, we found that bile acids, a prevalent constituent of the human proximal small intestine, increase intracellular c-di-GMP in V. cholerae. We identified four c-di-GMP turnover enzymes that contribute to increased intracellular c-di-GMP in the presence of bile acids, and deletion of these enzymes eliminates the bile induction of c-di-GMP and biofilm formation. Furthermore, this bile-mediated increase in c-di-GMP is quenched by bicarbonate, the intestinal pH buffer secreted by intestinal epithelial cells. Our results lead us to propose that V. cholerae senses distinct microenvironments within the small intestine using bile and bicarbonate as chemical cues and responds by modulating the intracellular concentration of c-di-GMP. PMID:24799624

  8. BICARBONATE OF SODA BLASTING TECHNOLOGY FOR AIRCRAFT WHEEL PAINTING

    EPA Science Inventory

    This evaluation addressed product quality, waste reduction/pollution prevention and economics in replacing chemical solvent strippers with a bicarbonate of soda blasting technology for removal of paint from aircraft wheels. The evaluation was conducted in the Paint Stripping Sho...

  9. BICARBONATE OF SODA BLASTING TECHNOLOGY FOR AIRCRAFT WHEEL DEPAINTING

    EPA Science Inventory

    This evaluation addressed product quality, waste reduction/pollution prevention and economics in replacing chemical solvent strippers with a bicarbonate of soda blasting technology for removal of point from aircraft wheels. he evaluation was conducted in the Paint Stripping Shop ...

  10. Distal Renal Tubular Acidosis in Infancy: A Bicarbonate Wasting State

    ERIC Educational Resources Information Center

    Rodriguez-Soriano, J.; And Others

    1975-01-01

    Studied were three unrelated infants with distal renal tubular acidosis (a condition characterized by an inability to acidify the urine to minimal pH levels resulting in the loss of bicarbonates). (DB)

  11. Effect of Sodium Bicarbonate Preloading on Ischemic Renal Failure

    Microsoft Academic Search

    James L. Atkins

    1986-01-01

    Rats pretreated with sodium bicarbonate were functionally protected from the damage of bilateral renal artery occlusion. The rise in serum creatinine (day 1 minus day 0) during the first 24 h after ischemia was 2.88 ± 0.28 mg% in the bicarbonate-loaded animals versus 3.90 ± 0.26 mg% in their matched controls (p ? 0.01). Pretreatment with acetazolamide produced a similar

  12. VIEW OF RBC (REFINED BICARBONATE) BUILDING LOOKING NORTHEAST. DEMOLITION IN ...

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

    VIEW OF RBC (REFINED BICARBONATE) BUILDING LOOKING NORTHEAST. DEMOLITION IN PROGRESS. "ARM & HAMMER BAKING SODA WAS MADE HERE FOR OVER 50 YEARS AND THEN SHIPPED ACROSS THE STREET TO THE CHURCH & DWIGHT PLANT ON WILLIS AVE. (ON THE RIGHT IN THIS PHOTO). LAYING ON THE GROUND IN FRONT OF C&D BUILDING IS PART OF AN RBC DRYING TOWER. - Solvay Process Company, Refined Bicarbonate Building, Between Willis & Milton Avenues, Solvay, Onondaga County, NY

  13. Potency and recovery characteristics of rocuronium mixed with sodium bicarbonate.

    PubMed

    Lee, H J; Kim, K S; Yeon, J T; Suh, J K; Sung, I H; Shin, I C

    2010-09-01

    Sodium bicarbonate may be added to rocuronium to decrease pain on injection. However, this mixture may result in the formation of carbon dioxide bubbles. We investigated whether the addition of sodium bicarbonate to rocuronium alters neuromuscular blockade, in 120 patients randomly assigned to receive rocuronium mixed with saline or bicarbonate 8.4%, either in varying doses (for dose-response measurements; 60 patients) or a fixed dose of 600 ?g.kg(-1) (for time-course measurements; 60 patients). Sodium bicarbonate resulted in a left-shift of the rocuronium dose-response curve. The effective doses of rocuronium to produce 95% twitch depression were 331.6 (95% CI: 310.4-352.8) and 284.3 (95% CI: 262.0-306.6) ?g.kg(-1) mixed with isotonic saline or sodium bicarbonate, respectively (p < 0.001). The mean (SD) onset times of rocuronium 600 ?g.kg(-1) were 3.6 (0.6) and 2.7 (0.5) min in the corresponding groups, respectively (p < 0.001). The mean (SD) times to 95% recovery were 35.8 (5.8) and 47.9 (7.1) min, respectively (p < 0.001). We conclude that the mixing of sodium bicarbonate with rocuronium enhances the potency, shortens the onset and prolongs the duration of action. PMID:20608923

  14. Common data buffer

    NASA Technical Reports Server (NTRS)

    Byrne, F.

    1981-01-01

    Time-shared interface speeds data processing in distributed computer network. Two-level high-speed scanning approach routes information to buffer, portion of which is reserved for series of "first-in, first-out" memory stacks. Buffer address structure and memory are protected from noise or failed components by error correcting code. System is applicable to any computer or processing language.

  15. Ammonium diphosphitoindate(III).

    PubMed

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

    2013-04-01

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

  16. 21 CFR 184.1138 - Ammonium chloride.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...Ammonium chloride (NH4 Cl, CAS Reg. No. 12125-02-9) is produced by the reaction of sodium chloride and an ammonium salt in solution. The less soluble sodium salt separates out at elevated temperatures, and ammonium chloride is...

  17. 21 CFR 184.1138 - Ammonium chloride.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...Ammonium chloride (NH4 Cl, CAS Reg. No. 12125-02-9) is produced by the reaction of sodium chloride and an ammonium salt in solution. The less soluble sodium salt separates out at elevated temperatures, and ammonium chloride is...

  18. 21 CFR 184.1138 - Ammonium chloride.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...Ammonium chloride (NH4 Cl, CAS Reg. No. 12125-02-9) is produced by the reaction of sodium chloride and an ammonium salt in solution. The less soluble sodium salt separates out at elevated temperatures, and ammonium chloride is...

  19. 21 CFR 184.1138 - Ammonium chloride.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...Ammonium chloride (NH4 Cl, CAS Reg. No. 12125-02-9) is produced by the reaction of sodium chloride and an ammonium salt in solution. The less soluble sodium salt separates out at elevated temperatures, and ammonium chloride is...

  20. 21 CFR 184.1138 - Ammonium chloride.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...Ammonium chloride (NH4 Cl, CAS Reg. No. 12125-02-9) is produced by the reaction of sodium chloride and an ammonium salt in solution. The less soluble sodium salt separates out at elevated temperatures, and ammonium chloride is...

  1. 76 FR 47238 - Ammonium Nitrate From Russia

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-04

    ...Second Review] Ammonium Nitrate From Russia Determination On the basis of the record...antidumping duty order on ammonium nitrate from Russia would be likely to lead to continuation...2011), entitled Ammonium Nitrate from Russia: Investigation No....

  2. 76 FR 11273 - Ammonium Nitrate From Russia

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-01

    ...Second Review)] Ammonium Nitrate From Russia AGENCY: United States International Trade...investigation on ammonium nitrate from Russia...investigation on ammonium nitrate from Russia would be likely to lead to...

  3. Short-term assay of soil urease activity using colorimetric determination of ammonium

    Microsoft Academic Search

    E. Kandeler; H. Gerber

    1988-01-01

    A rapid assay for soil urease in the absence of bacteriostatic agents has been developed. The method comprises incubation of soil with an aqueous or buffered urea solution, extraction of ammonium with 1 N KCl and 0.01 NHCl and colorimetric NH4+ determination by a modified indophenol reaction. The method is characterized by high sensitivity and stability of the coloured complex

  4. The influence of the buffering capacity on the production of organic acids and alcohols from wastewater in anaerobic reactor.

    PubMed

    Silva, A J; Pozzi, E; Foresti, E; Zaiat, M

    2015-02-01

    Some bacteria common in anaerobic digestion process can ferment a broad variety of organic compounds to organic acids, alcohols, and hydrogen, which can be used as biofuels. Researches are necessary to control the microbial interactions in favor of the alcohol production, as intermediary products of the anaerobic digestion of organic compounds. This paper reports on the effect of buffering capacity on the production of organic acids and alcohols from wastewater by a natural mixed bacterial culture. The hypothesis tested was that the increase of the buffering capacity by supplementation of sodium bicarbonate in the influent results in benefits for alcohol production by anaerobic fermentation of wastewater. When the influent was not supplemented with sodium bicarbonate, the chemical oxygen demand (COD)-ethanol and COD-methanol detected in the effluent corresponded to 22.5 and 12.7 % of the COD-sucrose consumed. Otherwise, when the reactor was fed with influent containing 0.5 g/L of sodium bicarbonate, the COD-ethanol and COD-methanol were effluents that corresponded to 39.2 and 29.6 % of the COD-sucrose consumed. Therefore, the alcohol production by supplementation of the influent with sodium bicarbonate was 33.6 % higher than the fermentation of the influent without sodium bicarbonate. PMID:25480346

  5. Effect of sodium bicarbonate and beta-alanine supplementation on maximal sprint swimming

    PubMed Central

    2013-01-01

    Background This study examined the effect of simultaneous supplementation of extracellular buffer sodium bicarbonate (SB) and intracellular buffer beta-alanine (BA) on maximal sprint swimming. Methods Thirteen competitive male swimmers completed 4 different treatments (placebo [PL], SB, BA?+?PL, and BA + SB) in a crossover procedure. PL or SB supplementation (0.3 g/kg body weight) was ingested 60 min before two maximal 100-m freestyle swims that were performed with a passive recovery of 12-min between each swim. Because of the known long washout period for carnosine, four weeks of BA supplementation (4.8 g per day) was started after the first week of PL or SB supplementation and performance testing. Results The first maximal swims were similar, but the increase in time of the second versus the first 100-m swimming time was 1.5 s more (p < 0.05) in PL than in SB. Blood pH values were significantly (p < 0.05) greater in the SB and in the BA + SB groups compared to the PL and BA + PL values. There were no differences in peak blood lactate between the treatments. Conclusion Supplementing with SB prior to performing maximal sprint swimming with repetitions under 60 s improves performance. However, co-supplementation with SB and BA did not confer any added benefit on maximal swim performance. PMID:24215679

  6. Bicarbonate produced from carbon capture for algae culture.

    PubMed

    Chi, Zhanyou; O'Fallon, James V; Chen, Shulin

    2011-11-01

    Using captured CO(2) to grow microalgae is limited by the high cost of CO(2) capture and transportation, as well as significant CO(2) loss during algae culture. Moreover, algae grow poorly at night, but CO(2) cannot be temporarily stored until sunrise. To address these challenges, we discuss a process where CO(2) is captured as bicarbonate and used as feedstock for algae culture, and the carbonate regenerated by the culture process is used as an absorbent to capture more CO(2). This process would significantly reduce carbon capture costs because it does not require additional energy for carbonate regeneration. Furthermore, not only would transport of the aqueous bicarbonate solution cost less than for that of compressed CO(2), but using bicarbonate would also provide a superior alternative for CO(2) delivery to an algae culture system. PMID:21775005

  7. High performance ammonium nitrate propellant

    NASA Technical Reports Server (NTRS)

    Anderson, F. A. (inventor)

    1979-01-01

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

  8. Thermal decomposition of ammonium uranates

    Microsoft Academic Search

    Taichi Sato; Shigeaki Shiota

    1985-01-01

    The thermal decomposition of ammonium uranates precipitated from uranyl nitrate solution on the addition of aqueous ammonium hydroxide and hexamine under various conditions has been studied by means of thermogravimetry, differential thermal analysis, infrared spectroscopy and X-ray diffraction. Although all precipitates show the composition corresponding to UO3 · NH3 · H2O, the precipitates with hexamine give X-ray diffraction patterns designed

  9. The effects of acidosis and bicarbonate on action potential repolarization in canine cardiac Purkinje fibers

    PubMed Central

    1979-01-01

    Studies were performed on canine cardiac Purkinje fibers to evaluate the effects of acidosis and bicarbonate (HCO3) on action potential repolarization. Extracellular pH (pHe) was reduced from 7.4 to 6.8 by increasing carbon dioxide (CO2) concentration from 4 to 15% in a HCO3- buffered solution or by NaOH titration in a Hepes-buffered solution. Both types of acidosis produced a slowing of the rate of terminal repolarization (i.e., period of repolarization starting at about -60 mV and ending at the maximum diastolic potential) with an attendant increase in action potential duration of 10--20 ms. This was accompanied by a reduction in the maximum diastolic potential of 2--8 mV. In contrast, if the same pH change was made by keeping CO2 concentration constant and lowering extracellular HCO3 from 23.7 to 6.0 mM, in addition to the slowing of terminal repolarization, the plateau was markedly prolonged resulting in an additional 50- to 80-ms increase in action potential duration. If pHe was held constant at 7.4 and HCO3 reduced from 23.7 mM to 0 (Hepes-buffered solution), the changes in repolarization were nearly identical to those seen in 6.0 mM HCO3 except that terminal repolarization was unchanged. This response was unaltered by doubling the concentration of Hepes. Reducing HCO3 to 12.0 mM produced changes in repolarization of about one-half the magnitude of those in 6.0 mM HCO3. These findings suggest that in Purkinje fibers, HCO3 either acts as a current that slows repolarization or modulates the ionic currents responsible for repolarization. PMID:438770

  10. Adverse Effect of Ammonium Salts on the Antibacterial Activity of Paraformaldehyde Solutions

    PubMed Central

    Myers, G. E.; McCready, R. G. L.

    1963-01-01

    The antibacterial activity of aqueous solutions of paraformaldehyde in concentrations from 0.1 to 0.4% (w/v) is bacteriostatic rather than bactericidal in the presence or absence of ammonium chloride. The presence of ammonium chloride significantly lengthened the time of exposure to paraformaldehyde necessary for inhibition of growth of the test organism (Staphylococcus aureus FDA 209) when unbuffered solutions were used. Elevation of the pH of the reacting mixture of paraformaldehyde and ammonium chloride by partial buffering lengthened the time of exposure necessary for inhibition of growth of the test organism. Decrease of antibacterial activity was concomitant with the disappearance of paraformaldehyde from the reacting mixture. The reaction of paraformaldehyde with ammonium chloride was rapid at room temperature (25 C) and at pH levels near neutrality. The fate of the reacting paraformaldehyde, including the possibility of the formation of hexamethylenetetramine or methylenimine, is discussed with particular reference to loss of antibacterial activity. PMID:13936950

  11. Sodium Bicarbonate for the Treatment of Lactic Acidosis

    Microsoft Academic Search

    Sean M. Forsythe; Gregory A. Schmidt

    Lactic acidosis often challenges the intensivist and is associated with a strikingly high mortality. Treatment involves discerning and correcting its underlying cause, ensuring adequate oxygen delivery to tissues, reducing oxygen demand through sedation and mechanical ventilation, and (most controversially) attempting to alkalinize the blood with IV sodium bicarbonate. Here we review the literature to answer the following questions: Is a

  12. CCMR: Investigation of Potential Buffer Solutions and Concentrations for an Electrochemical Microfluidic Biosensor

    NSDL National Science Digital Library

    Wiles, Laura K.

    2009-08-15

    Biosensors are analytical devices that are being used to detect a variety of analytes including pathogens via antibody recognition. Liposomes have been used in the Baeumner research group for signal generation and amplification. In one detection strategy, electrochemical signals are being reported by entrapping a redox couple in the inner cavity of the liposomes and releasing them upon detection of the pathogen. The main task of this research was the optimization of a buffer system that can be used for the entrapment of the redox couple and does not inhibit the oxidation and reduction reactions on a gold electrode. Potassium ferrihexacyanide and potassium ferrohexacyanide (ferri/ferrohexacyanide) were used as redox couple and dissolved in 0.01M bicarbonate buffer, pH 7.0; 0.01M and 0.1M sodium borate buffers, pH 7.0; and 0.01M and 0.1M phosphate buffers, pH 7.0. The current produced by flowing each of these solutions through a 500?m long by 50?m deep channel in polydimethylsiloxane (PDMS) over the interdigitated ultramicroelectrode array (IDUA) was measured using amperometry. The resulting signal peaks created by the redox cycling of ferri/ferrohexacyanide on the electrode were compared. A 10?M solution of ferri/ferrohexacyanide gave signals of 0.44nA in 0.01M phosphate buffer, 0.41nA in sodium borate, 0.37nA in sodium borate diluted in phosphate buffer, and 0.04nA in 0.01M bicarbonate. Since the phosphate buffer cannot be used for liposome synthesis, it was determined that the sodium borate buffer might be the best alternative.

  13. Correction of hyperkalemia by bicarbonate despite constant blood pH

    Microsoft Academic Search

    Donald S Fraley; Sheldon Adler

    1977-01-01

    Correction of hyperkalemia by bicarbonate despite constant blood pH. Patients having hyperkalemia often are given bicarbonate to raise blood pH and shift extracellular potassium into cells. Blood pH in many hyperkalemic patients, however, is compensated. To determine whether bicarbonate, independent of its pH action, affects plasma potassium, 14 hyperkalemic patients were treated with bicarbonate in 5% dextrose. In five patients

  14. Removal of co-present chromate and arsenate by zero-valent iron in groundwater with humic acid and bicarbonate.

    PubMed

    Liu, Tongzhou; Rao, Pinhua; Mak, Mark S H; Wang, Peng; Lo, Irene M C

    2009-05-01

    The interactions of co-present Cr(VI) and As(V), and the influences of humic acid and bicarbonate in the process of Cr(VI) and As(V) removal by Fe(0) were investigated in a batch setting using simulated groundwater with 5 mM NaCl, 1 mM Na(2)SO(4), and 0.8 mM CaCl(2) as background electrolytes at an initial pH value of 7. Cr(VI) and As(V) were observed to be subject to different impacts induced by co-existing As(V) or Cr(VI), humic acid and bicarbonate, originating from their distinct removal mechanisms by Fe(0). Cr(VI) removal is a reduction-dominated process, whereas As(V) removal principally involves adsorption onto iron corrosion products. Experimental results showed that Cr(VI) removal was not affected by the presence of As(V) and humic acid. However, As(V) removal appeared to be inhibited by co-present Cr(VI). When the Cr(VI) concentration was 2, 5, and 10 mg/L, in the absence of humic acid and bicarbonate, As(V) removal rate constants were decreased by 27.9%, 49.0%, and 61.2%, respectively, which probably resulted from competition between Cr(VI) and As(V) for adsorption sites of the iron corrosion products. Furthermore, the presence of humic acid significantly varied As(V) removal kinetics by delaying the formation and aggregation of iron hydroxides due to the formation of soluble Fe-humate complexes and stably dispersed fine iron hydroxides colloids. In the presence of bicarbonate, both Cr(VI) and As(V) removal was increased and the inhibitory effect of Cr(VI) on As(V) removal was suppressed, resulting from the buffering effects and the promoted iron corrosion induced by bicarbonate, and the formation of CaCO(3) in solution, which enhanced As(V) adsorption. PMID:19321187

  15. Proteins contribute insignificantly to the intrinsic buffering capacity of yeast cytoplasm

    SciTech Connect

    Poznanski, Jaroslaw [Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw (Poland)] [Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw (Poland); Szczesny, Pawel [Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw (Poland) [Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw (Poland); Institute of Experimental Plant Biology and Biotechnology, Faculty of Biology, University of Warsaw, Warsaw (Poland); Ruszczynska, Katarzyna [Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw (Poland)] [Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw (Poland); Zielenkiewicz, Piotr [Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw (Poland) [Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw (Poland); Institute of Experimental Plant Biology and Biotechnology, Faculty of Biology, University of Warsaw, Warsaw (Poland); Paczek, Leszek, E-mail: leszek.paczek@wum.edu.pl [Department of Immunology, Transplantology and Internal Medicine, Warsaw Medical University, Warsaw (Poland)] [Department of Immunology, Transplantology and Internal Medicine, Warsaw Medical University, Warsaw (Poland)

    2013-01-11

    Highlights: Black-Right-Pointing-Pointer We predicted buffering capacity of yeast proteome from protein abundance data. Black-Right-Pointing-Pointer We measured total buffering capacity of yeast cytoplasm. Black-Right-Pointing-Pointer We showed that proteins contribute insignificantly to buffering capacity. -- Abstract: Intracellular pH is maintained by a combination of the passive buffering of cytoplasmic dissociable compounds and several active systems. Over the years, a large portion of and possibly most of the cell's intrinsic (i.e., passive non-bicarbonate) buffering effect was attributed to proteins, both in higher organisms and in yeast. This attribution was not surprising, given that the concentration of proteins with multiple protonable/deprotonable groups in the cell exceeds the concentration of free protons by a few orders of magnitude. Using data from both high-throughput experiments and in vitro laboratory experiments, we tested this concept. We assessed the buffering capacity of the yeast proteome using protein abundance data and compared it to our own titration of yeast cytoplasm. We showed that the protein contribution is less than 1% of the total intracellular buffering capacity. As confirmed with NMR measurements, inorganic phosphates play a crucial role in the process. These findings also shed a new light on the role of proteomes in maintaining intracellular pH. The contribution of proteins to the intrinsic buffering capacity is negligible, and proteins might act only as a recipient of signals for changes in pH.

  16. Buffer strips trap contaminants

    E-print Network

    Nebraska-Lincoln, University of

    benefits, such as increasing habitat for wildlife and decreasing flood damage. Three researchater Buffer strips trap contaminants Three research and demonstration projects seek to determine last summer. The strips are 250 feet long and 50 feet wide and consist of grass; grass and shrubs

  17. Bicarbonate/chloride antiport in Vero cells: II. Mechanisms for bicarbonate-dependent regulation of intracellular pH

    SciTech Connect

    Olsnes, S.; Ludt, J.; Tonnessen, T.I.; Sandvig, K.

    1987-08-01

    The rates of bicarbonate-dependent uptake and efflux of /sup 22/Na/sup +/ in Vero cells were studied and compared with the uptake and efflux of /sup 36/Cl/sup -/. Both processes were strongly inhibited by DIDS. Whereas the transport of chloride increased approximately ten-fold when the internal pH was increased over a narrow range around neutrality, the uptake of Na/sup +/ was much less affected by changes in pH. The bicarbonate-linked uptake of /sup 22/Na/sup +/ was dependent on internal Cl- but not on internal Na/sup +/. At a constant external concentration of HCO/sub 3/-, the amount of /sup 22/Na/sup +/ associated with the cells increased when the internal concentration of HCO/sub 3/- decreased and vice versa, which is compatible with the possibility that the ion pair NaCO/sub 3/- is the transported species and that the transport is symmetric across the membrane. Bicarbonate inhibited the uptake of /sup 36/Cl/sup -/ both in the absence and presence of Na/sup +/. At alkaline internal pH, HCO/sub 3/- stimulated the efflux of /sup 36/Cl/sup -/ from preloaded cells, while at acidic internal pH both Na/sup +/ and HCO/sub 3/- were required to induce /sup 36/Cl/sup -/ efflux. We propose a model for how bicarbonate-dependent regulation of the internal pH may occur. This model implies the existence of two bicarbonate transport mechanisms that, under physiological conditions, transport OH(-)-equivalents in opposite directions across the plasma membrane.

  18. Heterotrophic bicarbonate assimilation is the main process of de novo organic carbon synthesis in hadal zone of the Hellenic Trench, the deepest part of Mediterranean Sea.

    PubMed

    Yakimov, Michail M; La Cono, Violetta; Smedile, Francesco; Crisafi, Francesca; Arcadi, Erika; Leonardi, Marcella; Decembrini, Franco; Catalfamo, Maurizio; Bargiela, Rafael; Ferrer, Manuel; Golyshin, Peter N; Giuliano, Laura

    2014-12-01

    Ammonium-oxidizing chemoautotrophic members of Thaumarchaea are proposed to be the key players in the assimilation of bicarbonate in the dark (ABD). However, this process may also involve heterotrophic metabolic pathways, such as fixation of carbon dioxide (CO2) via various anaplerotic reactions. We collected samples from the depth of 4900?m at the Matapan-Vavilov Deep (MVD) station (Hellenic Trench, Eastern Mediterranean) and used the multiphasic approach to study the ABD mediators in this deep-sea ecosystem. At this depth, our analysis indicated the occurrence of actively CO2-fixing heterotrophic microbial assemblages dominated by Gammaproteobacteria with virtually no Thaumarchaea present. [14C]-bicarbonate incorporation experiments combined with shotgun [14C]-proteomic analysis identified a series of proteins of gammaproteobacterial origin. More than quarter of them were closely related with Alteromonas macleodii ‘deep ecotype’ AltDE, the predominant organism in the microbial community of MVD. The present study demonstrated that in the aphotic/hadal zone of the Mediterranean Sea, the assimilation of bicarbonate is associated with both chemolithoauto- and heterotrophic ABD. In some deep-sea areas, the latter may predominantly contribute to the de novo synthesis of organic carbon which points at the important and yet underestimated role heterotrophic bacterial populations can play the in global carbon cycle/sink in the ocean interior. PMID:25756124

  19. Ammoniums quaternaires et pathologies professionnelles

    Microsoft Academic Search

    M.-L. Hemery

    2008-01-01

    Quaternary ammonium compounds are widely used in many occupations (conservation, cleaning and disinfection) and all the workers in these occupations are exposed to the potentially irritant or allergenic effects to these products. The clinical manifestations are usually dermatological but respiratory symptoms such as rhinitis or respiratory symptoms are more and more often seen by occupational disease. The nature of the

  20. Transplastomic integration of a cyanobacterial bicarbonate transporter into tobacco chloroplasts

    PubMed Central

    Pengelly, J. J. L.; Förster, B.; von Caemmerer, S.; Badger, M. R.; Price, G. D.; Whitney, S. M.

    2014-01-01

    Improving global yields of agricultural crops is a complex challenge with evidence indicating benefits in productivity are achieved by enhancing photosynthetic carbon assimilation. Towards improving rates of CO2 capture within leaf chloroplasts, this study shows the versatility of plastome transformation for expressing the Synechococcus PCC7002 BicA bicarbonate transporter within tobacco plastids. Fractionation of chloroplast membranes from transplastomic tobBicA lines showed that ~75% of the BicA localized to the thylakoid membranes and ~25% to the chloroplast envelope. BicA levels were highest in young emerging tobBicA leaves (0.12 ?mol m–2, ?7mg m–2) accounting for ~0.1% (w/w) of the leaf protein. In these leaves, the molar amount of BicA was 16-fold lower than the abundant thylakoid photosystem II D1 protein (~1.9 ?mol m–2) which was comparable to the 9:1 molar ratio of D1:BicA measured in air-grown Synechococcus PCC7002 cells. The BicA produced had no discernible effect on chloroplast ultrastructure, photosynthetic CO2-assimilation rates, carbon isotope discrimination, or growth of the tobBicA plants, implying that the bicarbonate transporter had little or no activity. These findings demonstrate the utility of plastome transformation for targeting bicarbonate transporter proteins into the chloroplast membranes without impeding growth or plastid ultrastructure. This study establishes the span of experimental measurements required to verify heterologous bicarbonate transporter function and location in chloroplasts and underscores the need for more detailed understanding of BicA structure and function to identify solutions for enabling its activation and operation in leaf chloroplasts. PMID:24965541

  1. Sodium bicarbonate ingestion improves performance in interval swimming

    Microsoft Academic Search

    Jiaping Gao; David L. Costill; Craig A. Horswill; Sung H. Park

    1988-01-01

    Summary  In an effort to determine the effects of bicarbonate (NaHCO3) ingestion on exercise performance, ten male college swimmers were studied during five different trials. Each trial consisted of five 91.4m (100-yd) front crawl swims with a two-minute rest interval between each bout. The trials consisted of two NaHCO3 treatments, two placebo trials and one test with no-drink. One hour before

  2. Sodium bicarbonate reduces postharvest decay development on melons

    Microsoft Academic Search

    Y. Aharoni; E. Fallik; A. Copel; M. Gil; S. Grinberg; J. D. Klein

    1997-01-01

    Sodium bicarbonate (SBC) inhibited in vitro mycelial growth of A. alternata, Fusarium spp. and R. stolonifer. SBC action was fungistatic rather than fungicidal. Coating commercially harvested ‘Galia’ and ‘Ein-Dor’ melons with wax containing 2% SBC reduced decay incidence after storage and shelf life simulation by four to seven-fold, to a commercially acceptable level of 6–7%, compared to untreated or waxed-treated

  3. Virginia Tech - Buffer Pool

    NSDL National Science Digital Library

    Cliff Shaffer

    Allows user to select from FIFO, LRU, and LFU page replacement strategies. User then gives a series of page requests and the AV shows the decisions made regarding page replacement. Simple to use, clearly shows the process. It would be nice if the user could pick the size of the backing memory and the buffer pool. Recommended as lecture aide, standalone, self-study suppliment to tutorial or lecture.

  4. Buck Buffer Leslie Vosshall

    E-print Network

    Buck Buffer Leslie Vosshall Axel Lab 5/7/1998 For high stringency hybridization of library screens.5 M Sodium Phosphate pH 7.3 1% BSA 4% SDS For 1 liter: Prewarm about 800 ml distilled water to 65 Phosphate Dibasic: 103.21 g (Heptahydrate, FW=268.07) **OR** 54.66 g (Anhydrous, FW=141.96) Mix until

  5. Comparative study of perdialytic volemia variability in chronic dialysis patients between acetate- free biofiltration and bicarbonate hemodialysis.

    PubMed

    Harzallah, Kais; Daiki, Mayssa; Baffoun, Anis; Salah, Mohamed Ben; Tagorti, Mohamed; Hichri, Nourredine; Hmida, Jalel

    2011-09-01

    We have developed since 1994 a new hemodialysis (HD) technique called acetate biofiltration 84% (AFB 84%) that is characterized by the absence of acetate in the dialysate and the complete correction of buffer balance by post- dilutional infusion of bicarbonate- based replacement solution. Our study aimed to compare the variability of perdialytic volemia [net ultrafiltration (UF) rate, total UF, ?weight (T4- T0)] during AFB 84% and bicarbonate dialysis (BD) for stable chronic hemodynamic patients. This was a prospective crossover study carried out on 14 patients for a total of 168 HD sessions (84 AFB 84% and 84 BD). Optical measurement of hemoglobin (Hb) concentration was incorporated into the dialysis monitor to allow the study of the relative blood volume. For both techniques, Hb measured by Hemoscan® correlated well with the laboratory measurements. Moreover, the comparison of the averages of the different indicators of the perdialytic volemia did not disclose any significant statistical differences. Nevertheless, the comparison of the variability of perdialytic volemia between both techniques showed less ? volemia (T4- T0) during the AFB 84% than the BD (- 7.909% for BD and - 6.960% for ABF 84%, P = 0.0036). We conclude that the absence of acetate and maintaining an optimal osmolarity at the origin of a better plasma refilling rate are key factors that make AFB 84% a technique assuring a better perdialyitic hemodynamic tolerance in comparison with BD in chronic HD patients. PMID:21912029

  6. Influence of Heterogeneous Ammonium Availability on Bacterial

    E-print Network

    Lovley, Derek

    and the Expression of Nitrogen Fixation and Ammonium Transporter Genes during in Situ Bioremediation of Uranium bioremediation of uranium-contaminated groundwater was evaluated. Ammonium concentrations varied by 2 orders microbial processes during bioremediation. Introduction

  7. Principles of database buffer management

    Microsoft Academic Search

    Wolfgang Effelsberg; Theo Haerder

    1984-01-01

    This paper discusses the implementation of a database buffer manager as a component of a DBMS. The interface between calling components of higher system layers and the buffer manager is described; the principal differences between virtual memory paging and database buffer management are outlined; the notion of referencing versus addressing of database pages is introduced; and the concept of fixing

  8. Bicarbonate-Dependent Secretion and Proteolytic Processing of Recombinant Myocilin

    PubMed Central

    Aroca-Aguilar, José-Daniel; Martínez-Redondo, Francisco; Martín-Gil, Alba; Pintor, Jesús; Coca-Prados, Miguel; Escribano, Julio

    2013-01-01

    Myocilin is an extracellular glycoprotein of poorly understood function. Mutations of this protein are involved in glaucoma, an optic neuropathy characterized by a progressive and irreversible visual loss and frequently associated with elevated intraocular pressure. We previously showed that recombinant myocilin undergoes an intracellular proteolytic processing by calpain II which cleaves the central region of the protein, releasing one N- and one C-terminal fragment. Myocilin cleavage is reduced by glaucoma mutations and it has been proposed to participate in intraocular pressure modulation. To identify possible factors regulating the proteolytic processing of recombinant myocilin, we used a cellular model in which we analyzed how different culture medium parameters (i.e., culture time, cell density, pH, bicarbonate concentration, etc.) affect the presence of the extracellular C-terminal fragment. Extracellular bicarbonate depletion associated with culture medium acidification produced a reversible intracellular accumulation of full-length recombinant myocilin and incremented its intracellular proteolytic processing, raising the extracellular C-terminal fragment percentage. It was also determined that myocilin intracellular accumulation depends on its N-terminal region. These data suggest that aqueous humor bicarbonate variations could also modulate the secretion and cleavage of myocilin present in ocular tissues. PMID:23342144

  9. Sodium bicarbonate treatment extends life of formerly acid lake

    SciTech Connect

    Not Available

    1988-02-01

    For the second time, researchers have used a familiar home remedy to restore the balance of a once acid lake. On September 29, Wolf Pond, in New York's Adirondack State Park, was treated with sodium bicarbonate to adjust alkalinity and keep pH at normal levels at least into the 1990's. Since it was first treated with bicarbonate in 1984, Wolf Pond has recovered and stabilized enough to sustain fish life once again. Repeated dosing is necessary because acid rain and runoff gradually deplete alkalinity in the lake over a period of years. Wolf Pond was selected for study because it has very little outflow and its major source of replenishment is rain. As the 1986 study explained, sodium bicarbonate was chosen for this application because it provides four advantages: (1) it is very soluble; (2) it cannot raise pH above 8.5; (3) it is easy to handle and apply; and (4) it is safe enough to be a common ingredient of many pharmaceuticals and foods.

  10. Electrochemical Studies on Silicate and Bicarbonate Ions for Corrosion Inhibitors

    NASA Astrophysics Data System (ADS)

    Mohorich, Michael E.; Lamb, Joshua; Chandra, Dhanesh; Daemen, Jaak; Rebak, Raul B.

    2010-10-01

    Several types of carbon and high-strength low-alloy (HSLA) steels are being considered for use in the underground reinforcement of the Yucca Mountain Nuclear Waste Repository. In this study, potentiodynamic polarization under reducing conditions was used to determine the corrosion rates (CRs) and passivity behavior of AISI 4340 steel using different combinations of sodium silicate (Na2SiO3) and sodium bicarbonate (NaHCO3), in both pure water (PW) and simulated seawater (SW, 3.5 pct NaCl). These experiments were carried out to examine the potential inhibiting properties of the silicate or bicarbonate ions on the surface of the steel. The addition of sodium silicate to solution reduced the observed CR at room temperature to 19 ?m/y at 0.005 M concentration and 7 ?m/y at 0.025 M concentration in PW. The addition of sodium bicarbonate increased the CR from 84 ?m/y (C = 0.1 M) to 455 ?m/y (C = 1 M). These same behaviors were also observed at higher temperatures.

  11. Isotonic sodium bicarbonate-triggered emodin release from borate stabilized emodin nanoparticles-loaded polymeric microgel films.

    PubMed

    Wang, Lin; Wang, Xiaohan; Li, Xiaozhou

    2014-07-20

    Hydrosoluble emodin-borate (EmB) nanoparticles (NPs) were fabricated by a simple solvent exchange method to address emodin's poor water solubility. As the result, negative charges were introduced in the surface of EmB NPs. In addition, layer-by-layer assembled multilayer films containing cation-rich polymeric microgels (named PAHD) and sodium carboxymethyl cellulose (NaCMC) were employed as drug carrier. Anionic EmB can be loaded into the PAHD/CMC multilayer films. The influences of various experimental parameters on cargo capacity of the PAHD/CMC film were studied in detail. The loaded EmB can be released in the form of emodin molecule in presence of isotonic sodium bicarbonate (ISB) solution. Gratifyingly, EmB did not almost release in presence of water, PBS buffer solution, 0.9% normal saline, and 5% glucose solution. PMID:24755249

  12. pH buffering does not influence BDNF responses to exercise.

    PubMed

    Rojas Vega, S; Hollmann, W; Vera Wahrmann, B; Strüder, H K

    2012-01-01

    The influence of acidosis on brain-derived neurotrophic factor (BDNF) was examined by buffering pH changes during 10 min of continuous low intensity (LIE) and following high intensity cycling exercise to exhaustion (HIE). 11 athletes participated in 2 trials separated by 1 week. Individuals received either a placebo infusion (isotonic saline) or an isotonic sodium bicarbonate infusion before and during exercise. Blood samples were drawn at rest, after LIE and after HIE, as well as 3, 6, 10 and 15 min post exercise. During placebo trial, HIE induced a profound decrease (p<0.01) of capillary blood bicarbonate concentration (HCO3-), pH, base excess (BE) and pCO2. Higher (p<0.01) HCO3-, pH and BE were found during bicarbonate infusion and post exercise in comparison to the placebo trial. Exercise induced an identical increase of blood lactate concentration in both trials. Serum BDNF concentration was increased (p<0.01) at the end of HIE and remained elevated until 3 min post exercise in both trials. The present study suggests that during HIE lactate might have an acidosis-independed impact on BDNF secretion because buffering of blood gases, that attenuate the fall of pH but not the accumulation of lactic acid, failed to alter the exercise-induced increase of BDNF. PMID:22127561

  13. 21 CFR 573.170 - Ammonium formate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...is manufactured by the reaction of 99.5 percent ammonia...of 37 percent ammonium salt of formic acid and 62...37 percent ammonium salt of formic acid and 62...37 percent ammonium salt of formic acid and 62...for reporting adverse reactions or to request a...

  14. 21 CFR 573.170 - Ammonium formate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...is manufactured by the reaction of 99.5 percent ammonia...of 37 percent ammonium salt of formic acid and 62...37 percent ammonium salt of formic acid and 62...37 percent ammonium salt of formic acid and 62...for reporting adverse reactions or to request a...

  15. 21 CFR 573.170 - Ammonium formate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...is manufactured by the reaction of 99.5 percent ammonia...of 37 percent ammonium salt of formic acid and 62...37 percent ammonium salt of formic acid and 62...37 percent ammonium salt of formic acid and 62...for reporting adverse reactions or to request a...

  16. 21 CFR 573.170 - Ammonium formate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...is manufactured by the reaction of 99.5 percent ammonia...of 37 percent ammonium salt of formic acid and 62...37 percent ammonium salt of formic acid and 62...37 percent ammonium salt of formic acid and 62...for reporting adverse reactions or to request a...

  17. Using ammonium bicarbonate as pore former in activated carbon catalyst layer to enhance performance of air cathode microbial fuel cell

    NASA Astrophysics Data System (ADS)

    Li, Da; Qu, Youpeng; Liu, Jia; He, Weihua; Wang, Haiman; Feng, Yujie

    2014-12-01

    The rolling catalyst layers in air cathode microbial fuel cells (MFCs) are prepared by introducing NH4HCO3 as pore former (PF) with four PF/activated carbon mass ratios of 0.1, 0.2, 0.3 and 1.0. The maximum power density of 892 ± 8 mW m-2 is obtained by cathodes with the mass ratio of 0.2, which is 33% higher than that of the control reactor (without PF, 671 ± 22 mW m-2). Pore analysis indicates the porosity increases by 38% and the major pore range concentrates between 0.5 ?m-0.8 ?m which likely facilitates to enrich the active reaction sites compared to 0.8 ?m-3.0 ?m in the control and other PF-cathodes. In addition, pore structure endows the cathode improved exchange current density by 2.4 times and decreased charge transfer resistance by 44%, which are the essential reasons to enhance the oxygen reduction. These results show that addition of NH4HCO3 proves an effective way to change the porosity and pore distribution of catalyst layers and then enhance the MFC performance.

  18. Deliquescence, Efflorescence, and Water Activity in Ammonium Nitrate and Mixed Ammonium Nitrate/Succinic Acid Microparticles

    E-print Network

    not take up a significant amount of water. Additionally, the deliquescence relative humidity is foundDeliquescence, Efflorescence, and Water Activity in Ammonium Nitrate and Mixed Ammonium Nitrate of ammonium nitrate/water and mixed ammonium nitrate/succinic acid/water microparticles. The water activity

  19. Acid Rain Experiments: Soil Buffering

    NSDL National Science Digital Library

    This experiment will help students understand that soil sometimes contains substances, like limestone, that buffer acids or bases, and that some salts in soil may also act as buffers. They will collect soil samples from their lawn, garden, or school and look for buffering effects by observing the pH change of an acid mixture poured through the samples. If the water collected from the sample is less acidic than the original mixture, then the soil is buffering some of the acid. If it does not change, then the soil may not be capable of buffering acids.

  20. Prediction of aerobic and anaerobic capacities of elite cyclists from changes in lactate during isocapnic buffering phase.

    PubMed

    Hasanli, Mohsen; Nikooie, Rohollah; Aveseh, Malihe; Mohammad, Fashi

    2015-02-01

    Hasanli, M, Nikooie, R, Aveseh, M, and Mohammad, F. Prediction of aerobic and anaerobic capacities of elite cyclists from changes in lactate during isocapnic buffering phase. J Strength Cond Res 29(2): 321-329, 2015-This study predicted aerobic and anaerobic capacities using relative changes of arterial blood lactate during the isocapnic buffering phase (relative [La]ISBP). Fourteen male professional cyclists (sprint-trained [n = 6] and endurance [n = 8]) performed 2 exercise sessions to exhaustion on a cycle ergometer; 1 incremental standard test to determine the isocapnic buffering phase, buffering capacities, and relative [La]ISBP and 1 supramaximal exercise test to determine maximal accumulated oxygen deficit (MAOD). The time between Lactate threshold (LT) and respiratory compensatory threshold (RCT) was considered to be the isocapnic buffering phase. Total buffering capacity was calculated as ?[La]·?pH. Bicarbonate buffering was calculated as ?[HCO3]·?pH, and the difference between -?[La]·?pH and ?[HCO3]·?pH was considered as nonbicarbonate buffering. The lactate concentration for LT (p ? 0.05) and RCT (p ? 0.05), and relative [La]ISBP (p < 0.01) were significantly lower for endurance cyclists than for sprint-trained cyclists. A significant difference was found for bicarbonate buffering capacity between groups (p < 0.01). A significant correlation was found between relative [La]ISBP with (Equation is included in full-text article.)(r = -0.71, p ? 0.05) and MAOD (r = 0.73, p < 0.01). Relative [La]ISBP was useful for predicting aerobic power (R = 51%) and anaerobic capacity (R = 53%). These results demonstrated that relative [La]ISBP is an important variable in intermediary metabolism and in addition to (Equation is included in full-text article.)and LT is recommended for better evaluation of performance of athletes who show nearly equal contributions from the aerobic and anaerobic energy systems during exercise. PMID:25144132

  1. The Cu(II) complex of Abeta40 peptide in ammonium acetate solutions. Evidence for ternary species formation.

    PubMed

    Rózga, Ma?gorzata; Protas, Anna M; Jab?onowska, Agnieszka; Dadlez, Micha?; Bal, Wojciech

    2009-03-21

    Fluorimetric Cu(ii) titrations of Alzheimer's disease (AD) Abeta40 peptide at various ammonium acetate concentrations demonstrated that ternary Cu(Abeta40)L complexes are formed with buffer components L, thereby providing a novel perspective on Cu(ii)-Abeta interactions. PMID:19259592

  2. Buffer capacity of the coelomic fluid in echinoderms.

    PubMed

    Collard, Marie; Laitat, Kim; Moulin, Laure; Catarino, Ana I; Grosjean, Philippe; Dubois, Philippe

    2013-09-01

    The increase in atmospheric CO2 due to anthropogenic activity results in an acidification of the surface waters of the oceans. The impact of these chemical changes depends on the considered organisms. In particular, it depends on the ability of the organism to control the pH of its inner fluids. Among echinoderms, this ability seems to differ significantly according to species or taxa. In the present paper, we investigated the buffer capacity of the coelomic fluid in different echinoderm taxa as well as factors modifying this capacity. Euechinoidea (sea urchins except Cidaroidea) present a very high buffer capacity of the coelomic fluid (from 0.8 to 1.8mmolkg(-1) SW above that of seawater), while Cidaroidea (other sea urchins), starfish and holothurians have a significantly lower one (from -0.1 to 0.4mmolkg(-1) SW compared to seawater). We hypothesize that this is linked to the more efficient gas exchange structures present in the three last taxa, whereas Euechinoidea evolved specific buffer systems to compensate lower gas exchange abilities. The constituents of the buffer capacity and the factors influencing it were investigated in the sea urchin Paracentrotus lividus and the starfish Asterias rubens. Buffer capacity is primarily due to the bicarbonate buffer system of seawater (representing about 63% for sea urchins and 92% for starfish). It is also partly due to coelomocytes present in the coelomic fluid (around 8% for both) and, in P. lividus only, a compound of an apparent size larger than 3kDa is involved (about 15%). Feeding increased the buffer capacity in P. lividus (to a difference with seawater of about 2.3mmolkg(-1) SW compared to unfed ones who showed a difference of about 0.5mmolkg(-1) SW) but not in A. rubens (difference with seawater of about 0.2 for both conditions). In P. lividus, decreased seawater pH induced an increase of the buffer capacity of individuals maintained at pH7.7 to about twice that of the control individuals and, for those at pH7.4, about three times. This allowed a partial compensation of the coelomic fluid pH for individuals maintained at pH7.7 but not for those at pH7.4. PMID:23752123

  3. 49 CFR 176.415 - Permit requirements for Division 1.5, ammonium nitrates, and certain ammonium nitrate fertilizers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...nitrates, and certain ammonium nitrate fertilizers. 176.415 Section 176.415 ...nitrates, and certain ammonium nitrate fertilizers. (a) Except as provided in...Ammonium nitrate UN1942, ammonium nitrate fertilizers containing more than 70%...

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

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...nitrates, and certain ammonium nitrate fertilizers. 176.415 Section 176.415 ...nitrates, and certain ammonium nitrate fertilizers. (a) Except as provided in...Ammonium nitrate UN1942, ammonium nitrate fertilizers containing more than 70%...

  5. 49 CFR 176.415 - Permit requirements for Division 1.5, ammonium nitrates, and certain ammonium nitrate fertilizers.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...nitrates, and certain ammonium nitrate fertilizers. 176.415 Section 176.415 ...nitrates, and certain ammonium nitrate fertilizers. (a) Except as provided in...Ammonium nitrate UN1942, ammonium nitrate fertilizers containing more than 70%...

  6. 49 CFR 176.415 - Permit requirements for Division 1.5, ammonium nitrates, and certain ammonium nitrate fertilizers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...nitrates, and certain ammonium nitrate fertilizers. 176.415 Section 176.415 ...nitrates, and certain ammonium nitrate fertilizers. (a) Except as provided in...Ammonium nitrate UN1942, ammonium nitrate fertilizers containing more than 70%...

  7. Regulation and roles of bicarbonate transporters in cancer

    PubMed Central

    Gorbatenko, Andrej; Olesen, Christina W.; Boedtkjer, Ebbe; Pedersen, Stine F.

    2014-01-01

    A unifying feature of solid tumors is a markedly altered pH profile compared to normal tissues. This reflects that solid tumors, despite completely different origins, often share several phenotypic properties with implications for intra- and extracellular pH. These include: a metabolic shift in most cancer cells toward more acid-producing pathways, reflecting both oncogenic signaling and the development of hypoxia in poorly perfused regions of the tumors; the poorly perfused and often highly dense tumor microenvironment, reducing the diffusive flux of acid equivalents compared to that in normal tissues; and the markedly altered regulation of the expression and activity of pH-regulatory transport proteins in cancer cells. While some of these properties of tumors have been well described in recent years, the great majority of the research in this clinically important area has focused on proton transport, in particular via the Na+/H+ exchanger 1 (SLC9A1, NHE1) and various H+ ATPases. We have, however, recently demonstrated that at least under some conditions, including in vitro models of HER2 positive breast cancer, and measurements obtained directly in freshly dissected human mammary carcinomas, bicarbonate transporters such as the electroneutral Na+, HCO?3 cotransporter (SLC4A7, NBCn1), are upregulated and play central roles in pH regulation. In this review, we summarize and discuss the current knowledge regarding the regulation and roles of bicarbonate transporters in cancer. Furthermore, we present new analyses of publicly available expression data demonstrating widely altered expression levels of SLC4- and SLC26 family transporters in breast-, lung-, and colon cancer patients, and we hypothesize that bicarbonate transporter dysregulation may have both diagnostic and therapeutic potential in cancer treatment. PMID:24795638

  8. The effect of sodium bicarbonate and sodium citrate ingestion on anaerobic power during intermittent exercise

    Microsoft Academic Search

    M. Parry-Billings; D. P. M. MacLaren

    1986-01-01

    Summary  The effect of sodium bicarbonate and sodium citrate ingestion on cycling performance in three 30 s Wingate Anaerobic Tests\\u000a separated by 6 min recovery periods has been studied using 6 male subjects. Subjects ingested either sodium bicarbonate (B),\\u000a sodium bicarbonate plus sodium citrate (BC), sodium citrate (C) or sodium chloride (P) 2.5 h prior to exercise in a dose of

  9. Molecular Cloning of a New Sodium Bicarbonate Cotransporter cDNA from Human Retina

    Microsoft Academic Search

    Kenichi Ishibashi; Sei Sasaki; Fumiaki Marumo

    1998-01-01

    Sodium bicarbonate cotransport is an electrogenic process and a principal regulator of pH. A recently cloned sodium bicarbonate cotransporter (NBC1) is predominantly expressed in kidney. The presence of several isoforms is suggested from functional studies. We have cloned a new member of this family from human retina, which was named hNBC2 (for human sodium bicarbonate cotransporter 2). The hNBC2 has

  10. Anion?exchange membrane, water, and sodium bicarbonate extractions as soil tests for phosphorus

    Microsoft Academic Search

    J. J. Schoenau; W. Z. Huang

    1991-01-01

    Three techniques were evaluated as soil P tests for western Canadian soils: anion?exchange membrane (AEM), water, and bicarbonate extraction. The AEM, water, and bicarbonate?extractable total P represented novel approaches to compare to the widely used bicarbonate?extractable inorganic P (traditional Olsen) soil test. In a range of Saskatchewan soils, similar trends in predicted relative P availability were observed for AEM, water

  11. Iron-catalyzed hydrogenation of bicarbonates and carbon dioxide to formates.

    PubMed

    Zhu, Fengxiang; Zhu-Ge, Ling; Yang, Guangfu; Zhou, Shaolin

    2015-02-01

    The catalytic hydrogenation of carbon dioxide and bicarbonate to formate has been explored extensively. The vast majority of the known active catalyst systems are based on precious metals. Herein, we describe an effective, phosphine-free, air- and moisture-tolerant catalyst system based on Knölker's iron complex for the hydrogenation of bicarbonate and carbon dioxide to formate. The catalyst system can hydrogenate bicarbonate at remarkably low hydrogen pressures (1-5?bar). PMID:25603778

  12. Mobilization of arsenic from subsurface sediments by effect of bicarbonate ions in groundwater

    Microsoft Academic Search

    Hossain M. Anawar; Junji Akai; Hiroshi Sakugawa

    2004-01-01

    Arsenic leaching by bicarbonate ions has been investigated in this study. Subsurface sediment samples from Bangladesh were treated with different carbonate and bicarbonate ions and the results demonstrate that the arsenic leaching efficiency of the carbonate solutions decreased in the order of Na2CO3>NaHCO3>BaCO3>MnCO3. Sodium carbonate and bicarbonate ions extracted arsenic most efficiently; Na2CO3 leached maximum 118.12 ?g\\/l of arsenic, and

  13. Manganese complexes with bicarbonate and sulfate in natural water

    USGS Publications Warehouse

    Hem, J.D.

    1963-01-01

    The association constant for the dissolved species MnHCO3+ was experimentally determined to be 63. From this value and a published constant for the species MNSO4 aq., a diagram was prepared showing per cent of dissolved manganese complexed in the presence of 10 to 10,000 p.p.m. bicarbonate and 1.0 to 10,000 p.p.m. sulfate. The rate of oxidation of Mn+2 in aerated water is greatly increased by increasing pH, and is retarded when SO4-2and HCO3- are present.

  14. Variability of acid-base status in acetate-free biofiltration 84% versus bicarbonate dialysis.

    PubMed

    Harzallah, Kais; Hichri, Nourredine; Mazigh, Chakib; Tagorti, Mohamed; Hmida, Ahmed; Hmida, Jalel

    2008-03-01

    The ultimate goal of hemodialysis (HD) treatment is to achieve the highest level of efficacy in the presence of maximal clinical tolerance. With an aim to offer good hemodynamic stability, as observed during the acetate-free biofiltration 14% (AFB 14%) to patients who are intolerant to bicarbonate dialysis (BD) and with less cost, we have developed since June 1994, a new HD technique, namely AFB 84%. This study was carried out to analyze acid-base variations during the AFB 84% in comparison to BD in hemodynamically stable patients on regular HD. This was a prospective randomized crossover study carried out on 12 patients (6 males and 6 females) for a total of 144 HD sessions (72 BD and 72 AFB 84%). Patients with decompensated cardiomyopathy, respiratory diseases or uncontrolled hypertension were not included in the trial. All the patients were treated with BD or AFB 84%; the latter is characterized by the absence of acetate in the dialysate and a complete correction of buffer balance by post-dilutional infusion of bicarbonate-based replacement solution. The comparison of pre-dialysis arterial acid-base and blood-gas parameters revealed no significant differences of pH, HCO(3)(-) and paCO(2) levels between the two techniques. Analysis of post-dialysis parameters showed that, among patients dialyzed with BD, there was over correction of metabolic acidosis with a tendency towards metabolic alkalosis. In contrast, in patients dialyzed with AFB 84%, we observed a significant improvement in pH and HCO(3)(-) levels but the increase in paCO(2) level was not significant. A comparison of these parameters between the two techniques showed statistically significant difference in pH, HCO(3)(-) and paCO(2) levels, but not for paO(2) level. AFB 84% can offer some important advantages with the complete absence of acetate from the substitution fluids, and permits a better correction of metabolic acidosis than BD, without causing alkalosis. PMID:18310870

  15. Virtual Frame Buffer Interface Program

    NASA Technical Reports Server (NTRS)

    Wolfe, Thomas L.

    1990-01-01

    Virtual Frame Buffer Interface program makes all frame buffers appear as generic frame buffer with specified set of characteristics, allowing programmers to write codes that run unmodified on all supported hardware. Converts generic commands to actual device commands. Consists of definition of capabilities and FORTRAN subroutines called by application programs. Developed in FORTRAN 77 for DEC VAX 11/780 or DEC VAX 11/750 computer under VMS 4.X.

  16. Equilibrium Studies of Sodium-Ammonium, Potassium-Ammonium, and Calcium-Ammonium Exchanges on Clinoptilolite Zeolite

    Microsoft Academic Search

    M. A. Jama; H. Yuecel

    1989-01-01

    Forward and reverse ion-exchange isotherms for the binary sodium-ammonium, potassium-ammonium, and calcium-ammonium systems on clinoptilolite have been measured in aqueous solutions at a total concentration of 0.1 equiv\\/dm 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

  17. The role of the anion in the reaction of reducing sugars with ammonium salts.

    PubMed

    Agyei-Aye, Kwasi; Chian, May X; Lauterbach, John H; Moldoveanu, Serban C

    2002-11-19

    Reactions of reducing sugars with ammonia and its compounds are important commercially, particularly in the preparation of flavors and caramel colors. However, such reactions generally produce a complex series of products ranging from simple molecules to complex polymeric materials, particularly since commercial systems generally involve mixtures of sugars as opposed to single sugars. This complexity has made understanding the mechanisms of such reactions difficult. Therefore, investigatory work has generally been focused on model systems. Herein we report one such study with model systems: the effects of the nature of the anion of the reactions of reducing sugars with ammonium salts. D-Glucose was reacted in aqueous solution with each of the following ammonium salts: acetate, bicarbonate, carbonate, chloride, citrate, formate, monohydrogenphosphate (DAP), sulfate, and sulfite. These reactions were carried out in a Parr bomb at 93 degrees C for 2.5 h. The initial pH of the reaction mixtures was adjusted to pH 8.0 at 25 degrees C. The resulting mixtures were analyzed by LC-MS, and the results were analyzed by comparing the product yields and distributions with those obtained with DAP. The major reaction product of interest was 2,6-deoxyfructosazine, as it had been shown to be a marker for the polymeric material formed from such reactions. It was found that ammonium salts of weak acids were much more effective in effecting the desired reactions than were those of strong acids; however, none was as effective as DAP. PMID:12433492

  18. ANAEROBIC AMMONIUM OXIDATION IN THE MARINE ENVIRONMENT

    Microsoft Academic Search

    Marcel M. M. Kuypers; Gaute Lavik; Bo Thamdrup

    Oceanographers noticed already many years ago that far less ammonium accumulated in anoxic fjords and basins, than would be\\u000a expected from the stoichiometry of heterotrophic denitrification. It was suggested that this ‘missing’ ammonium was oxidized\\u000a with nitrate to freeN2. Since then several otherworkers have argued based on chemical profiles that ammonium is oxidized anaerobically in oxygen\\u000a deficient marine sediments and

  19. BUFFERS AND VEGETATIVE FILTER STRIPS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Buffers and filter strips are areas of permanent vegetation located within and between agricultural fields and the water courses to which they drain. These buffers are intended to intercept and slow runoff thereby providing water quality benefits. In addition, in many settings they are intended to...

  20. Mechanisms of buffer therapy resistance

    PubMed Central

    Bailey, Kate M.; Wojtkowiak, Jonathan W.; Cornnell, Heather H.; Ribeiro, Maria C.; Balagurunathan, Yoganand; Hashim, Arig Ibrahim; Gillies, Robert J.

    2014-01-01

    Many studies have shown that the acidity of solid tumors contributes to local invasion and metastasis. Oral pH buffers can specifically neutralize the acidic pH of tumors and reduce the incidence of local invasion and metastatic formation in multiple murine models. However, this effect is not universal as we have previously observed that metastasis is not inhibited by buffers in some tumor models, regardless of buffer used. B16-F10 (murine melanoma), LL/2 (murine lung) and HCT116 (human colon) tumors are resistant to treatment with lysine buffer therapy, whereas metastasis is potently inhibited by lysine buffers in MDA-MB-231 (human breast) and PC3M (human prostate) tumors. In the current work, we confirmed that sensitive cells utilized a pH-dependent mechanism for successful metastasis supported by a highly glycolytic phenotype that acidifies the local tumor microenvironment resulting in morphological changes. In contrast, buffer-resistant cell lines exhibited a pH-independent metastatic mechanism involving constitutive secretion of matrix degrading proteases without elevated glycolysis. These results have identified two distinct mechanisms of experimental metastasis, one of which is pH-dependent (buffer therapy sensitive cells) and one which is pH-independent (buffer therapy resistant cells). Further characterization of these models has potential for therapeutic benefit. PMID:24862761

  1. Memory access buffering in multiprocessors

    Microsoft Academic Search

    Michel Dubois; Christoph Scheurich; Faye A. Briggs

    1986-01-01

    In highly-pipelined machines, instructions and data are prefetched and buffered in both the processor and the cache. This is done to reduce the average memory access latency and to take advantage of memory interleaving. Lock-up free caches are designed to avoid processor blocking on a cache miss. Write buffers are often included in a pipelined machine to avoid processor waiting

  2. Iron Oxide Removal from Soils and Clays by a Dithionite-Citrate System Buffered with Sodium Bicarbonate

    Microsoft Academic Search

    O. P. MEdinA; M. L. JACKSO

    1958-01-01

    The oxidation potential of dithionite (Na~S204) increases from 0.37 V to 0.73 V with increase in pH from 6 to 9, because hydroxyl is consumed during oxidation of dithionite. At tile same time the amount of iron oxide dissolved in 15 minutes falls off (from 100 percent to less than 1 percent extracted) with increase in pH from 6 to

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

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 false Division 1.5 materials, ammonium nitrate and ammonium nitrate...Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS CARRIAGE BY...

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

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...5 compatibility group D. (f) No mixture containing ammonium nitrate and any ingredient which would accelerate the decomposition of ammonium nitrate under conditions incident to transportation may be transported by vessel. [Amdt. 176-30,...

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

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...5 compatibility group D. (f) No mixture containing ammonium nitrate and any ingredient which would accelerate the decomposition of ammonium nitrate under conditions incident to transportation may be transported by vessel. [Amdt. 176-30,...

  6. 49 CFR 176.410 - Division 1.5 materials, ammonium nitrate and ammonium nitrate mixtures.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...5 compatibility group D. (f) No mixture containing ammonium nitrate and any ingredient which would accelerate the decomposition of ammonium nitrate under conditions incident to transportation may be transported by vessel. [Amdt. 176-30,...

  7. 49 CFR 176.410 - Division 1.5 materials, ammonium nitrate and ammonium nitrate mixtures.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...5 compatibility group D. (f) No mixture containing ammonium nitrate and any ingredient which would accelerate the decomposition of ammonium nitrate under conditions incident to transportation may be transported by vessel. [Amdt. 176-30,...

  8. Ammonium assmilation in spruce ectomycorrhizas

    SciTech Connect

    Chalot, M.; Brun, A.; Botton, B. (Univ. of nancy, Vandoeuvre-les-Nancy (France)); Stewart, G. (University College, London (England))

    1990-05-01

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

  9. Decline of acid-sensitive plant species in heathland can be attributed to ammonium toxicity in combination with low pH.

    PubMed

    van den Berg, Leon J L; Dorland, Edu; Vergeer, Philippine; Hart, Miron A C; Bobbink, Roland; Roelofs, Jan G M

    2005-05-01

    The effects of increasing ammonium concentrations in combination with different pH levels were studied on five heathland plant species to determine whether their occurrence and decline could be attributed to ammonium toxicity and/or pH levels. Plants were grown in growth media amended with four different ammonium concentrations (10, 100, 500 and 1000 micromol l(-1)) and two pH levels resembling acidified (pH 3.5 or 4) and weakly buffered (pH 5 or 5.5) situations. Survival of Antennaria dioica and Succisa pratensis was reduced by low pH in combination with high ammonium concentrations. Biomass decreased with increased ammonium concentrations and decreasing pH levels. Internal pH of the plants decreased with increasing ammonium concentrations. Survival of Calluna vulgaris, Deschampsia flexuosa and Gentiana pneumonanthe was not affected by ammonium. Moreover, biomass increased with increasing ammonium concentrations. Biomass production of G. pneumonanthe reduced at low pH levels. A decline of acid-sensitive species in heathlands was attributed to ammonium toxicity effects in combination with a low pH. PMID:15819917

  10. The role of sodium bicarbonate in the nucleation of noctilucent clouds

    E-print Network

    Boyer, Edmond

    The role of sodium bicarbonate in the nucleation of noctilucent clouds J. M. C. Plane School smoke, sodium bicarbonate (NaHCO3), provides par- ticularly eective condensation nuclei for noctilucent for the sublimation of H2O to bulk ice. A 1-dimensional model of sodium chemistry was then employed to show

  11. High sodium bicarbonate and acetate hemodialysis: Double-blind crossover comparison of hemodynamic and ventilatory effects

    Microsoft Academic Search

    William L Henrich; Terry D Woodard; Barry D Meyer; Timothy R Chappell; Lewis J Rubin

    1983-01-01

    High sodium bicarbonate and acetate hemodialysis: Double-blind crossover comparison of hemodynamic and ventilatory effects. The superiority of bicarbonate dialysis (Bi HD) over acetate dialysis (Ac HD) using a high sodium dialysate has not been established to our knowledge. We compared Bi HD to Ac HD over 6 weeks each in ten stable patients using a double-blind crossover design and a

  12. SODIUM BENTONITE OR SODIUM BICARBONATE AS AIDS IN FEEDING HIGH-CONCENTRATE DIETS TO LAMBS 1

    Microsoft Academic Search

    G. B. Huntington; R. J. Emerick; L. B. Embry

    2010-01-01

    SUMMARY Studies were conducted to compare bento- nite and sodium bicarbonate as dietary aids in adaptation and subsequent performance of lambs fed high-concentrate diets under various conditions of protein supplementation. Three protein variations, including no supplemental protein (NSP), soybean meal (SBM) or urea, were factored with a control, 2% or 4% sodium bentonite, and 2% or 4% sodium bicarbonate in

  13. Treatment with Potassium Bicarbonate Lowers Calcium Excretion and Bone Resorption in Older Men and Women

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bicarbonate has been implicated in bone health in older subjects on acid-producing diets in short-term studies. The objective of this study was to determine the effects of potassium bicarbonate and its components on changes in bone resorption and calcium excretion over 3 months in older men and wom...

  14. Conductance Regulator Bicarbonate Conductance and pH Regulatory Capability of Cystic Fibrosis Transmembrane

    E-print Network

    Machen, Terry E.

    Conductance Regulator Bicarbonate Conductance and pH Regulatory Capability of Cystic Fibrosis Bicarbonate conductance and pH regulatory capability of cystic fibrosis transmembrane conductance regulator J0 of California, Berkeley, CA 94720 Communicated by Hans H. Ussing, February 28, 1994 ABSTRACT The cystic fibrosis

  15. Bicarbonate Secretion in the Murine Gallbladder - Lessons for the Treatment of Cystic Fibrosis

    Microsoft Academic Search

    Alan W Cuthbert

    2001-01-01

    Summary The epithelium lining the gallbladder of mammalian species has absorptive and secretory functions. An important function is the secretion of a bicarbonate rich fluid that helps neutralise stomach acid and provides an appropriate environment for intestinal enzymes. In cystic fibrosis (CF) this secretory function is lost. This study concerns the bicarbonate secreting activity of murine gallbladders in vitro using

  16. Stability of ammonium fluoride-treated Si(100)

    NASA Astrophysics Data System (ADS)

    Houston, Michael R.; Maboudian, Roya

    1995-09-01

    X-ray photoelectron spectroscopy (XPS) and contact angle analyses have been employed to investigate the chemical stability of silicon surfaces treated by an ammonium fluoride (NH4F) solution. Consistent with earlier results [Dumas and Chabal, Chem. Phys. Lett. 181, 537 (1991)], it is found that an NH4F final etch produces surfaces exhibiting lower oxygen and carbon contamination levels in comparison to the surfaces obtained with the traditional HF or buffered HF (BHF) etch. In conjunction with lower contamination levels, surfaces treated in ammonium fluoride show higher contact angles with water, indicating lower surface free energies. The Si-H surfaces produced by the ammonium fluoride etch were found to remain hydrophobic for weeks in air and showed no signs of oxidation for several days. After an induction period of about one week in air, oxidation began to occur in a more rapid fashion. The stability of the Si-H surfaces in water was also investigated, and it was found that the oxygen contamination levels measured by x-ray photoelectron spectroscopy were extremely sensitive to the final rinse time. An induction period of approximately one hour in water existed before any signs of oxidation were evident. Despite the fact that the NH4F-treated samples were initially cleaner than the HF-treated samples, both of these surfaces showed similar temporal behavior in air and water. We attribute this finding to the surface topographies produced by these treatments, as well as to the extreme sensitivity of the results to such factors as water rinse time.

  17. Ammonium repression of nitrate reductase formation in Lemna minor L

    Microsoft Academic Search

    T. O. Orebamjo; G. R. Stewart

    1975-01-01

    The presence of ammonium is shown to inhibit the nitrate-promoted formation of nitrate reductase in Lemna minor L. The ammonium inhibition does not result from an inhibition of nitrate accumulation. The kinetics of the ammonium inhibition suggest it is not a direct effect of ammonium. The inhibition could result from the build up of a product of ammonium assimilation or

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

    SciTech Connect

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

    1989-12-01

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

  19. Influence of bicarbonate ions on the deterioration of mortar bars in sulfate solutions

    SciTech Connect

    Kunther, W., E-mail: Wolfgang.Kunther@empa.ch [Empa, Laboratory for Concrete and Construction Chemistry, Ueberlandstrasse 129, CH-8600 Duebendorf (Switzerland); Lothenbach, B. [Empa, Laboratory for Concrete and Construction Chemistry, Ueberlandstrasse 129, CH-8600 Duebendorf (Switzerland)] [Empa, Laboratory for Concrete and Construction Chemistry, Ueberlandstrasse 129, CH-8600 Duebendorf (Switzerland); Scrivener, K. [EPFL, Laboratory of Construction Materials, CH-1015 Lausanne (Switzerland)] [EPFL, Laboratory of Construction Materials, CH-1015 Lausanne (Switzerland)

    2013-02-15

    This work investigates the influence of bicarbonate ions on the deterioration of cementitious material exposed to sulfate ions. Mortars based on a CEM I and on a CEM III/B cement were investigated. Experimental investigations were compared to thermodynamic modeling and phase characterization to understand the differences in deterioration. The presence of bicarbonate ions significantly reduced the expansion of the CEM I mortars. Thermodynamic modeling showed that at high concentrations of bicarbonate ettringite and gypsum become unstable. Microstructural characterization combined with information from thermodynamic modeling suggests that conditions of high supersaturation with respect to ettringite are unlikely in the samples exposed in solutions containing bicarbonate. Consequently, expansive forces are not generated by the crystallization pressure of ettringite. There was little expansion of the CEM III/B sample even in the sodium sulfate solution. In the bicarbonate solution this mortar showed a highly leached zone at the surface in which calcite was observed.

  20. The addition of sodium bicarbonate to prilocaine solution during i.v. regional anesthesia.

    PubMed

    Solak, M; Aktürk, G; Erciyes, N; Ozen, I; Colak, M; Duman, E

    1991-10-01

    A comparison of plain prilocaine and bicarbonated prilocaine in intravenous regional anesthesia was studied in 30 patients undergoing upper extremity surgery. The patients were divided into two groups: one group was given anesthesia in the form of 1% prilocaine and the other group was given 1% prilocaine plus sodium bicarbonate. The onset of analgesia and anesthesia and recovery from analgesia and anesthesia were investigated in both groups. Bicarbonated prilocaine produced faster onset of analgesia when compared with plain prilocaine (P less than 0.01). The onset of anesthesia and recovery from analgesia and anesthesia were not statistically different between the two groups. Clinically, the intensity of anesthesia was better when bicarbonated prilocaine solution was used instead of plain prilocaine. We conclude that bicarbonated prilocaine is better than plain prilocaine during IVRA. PMID:1664629

  1. Addition of buffers to high quality alfalfa hay-based diets for dairy cows in early lactation.

    PubMed

    Eickelberger, R C; Muller, L D; Sweeney, T F; Abrams, S M

    1985-07-01

    Beginning 4 wk postpartum, 14 Holstein cows were paired according to expected calving date and lactation number and assigned randomly to one of two treatments in a single reversal experiment designed to study the effects of added buffers to high quality alfalfa hay-based diets. Cows were offered daily 14.5 kg of concentrate containing 0 or 2% sodium bicarbonate and .5% magnesium oxide (as fed), plus free choice high quality alfalfa hay in a ratio of forage:grain approaching 50:50 (dry matter). No differences were in milk production, milk fat percentage, fat-corrected milk, or dry matter intake. Dry matter intake of grain was decreased with addition of buffers. Kilograms fat-corrected milk per kilogram of dry matter intake were 1.41 and 1.45 for control and buffered diets. No differences were significant for rumen pH, ammonia concentration, molar proportions of acetate and propionate, or ratio of acetate: propionate. Concentrations of total volatile fatty acids were higher for cows fed the buffered diet. No differences were in blood acid-base status or in various serum metabolites. Urine pH was 8.11 and 8.20 for control and buffered diets. Fractional urinary excretion of magnesium and sodium was greater when cows consumed the buffered diet. Diet digestibilities and rate of passage were not affected by dietary buffers. Addition of sodium bicarbonate plus magnesium oxide did not improve performance of early lactation cows fed high quality alfalfa hay as the sole forage. PMID:2993390

  2. 21 CFR 520.1696a - Buffered penicillin powder, penicillin powder with buffered aqueous diluent.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 2012-04-01 false Buffered penicillin powder, penicillin powder with buffered aqueous diluent. 520...FORM NEW ANIMAL DRUGS § 520.1696a Buffered penicillin powder, penicillin powder with buffered...

  3. 21 CFR 520.1696a - Buffered penicillin powder, penicillin powder with buffered aqueous diluent.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Buffered penicillin powder, penicillin powder with buffered aqueous diluent. 520...FORM NEW ANIMAL DRUGS § 520.1696a Buffered penicillin powder, penicillin powder with buffered...

  4. 21 CFR 520.1696a - Buffered penicillin powder, penicillin powder with buffered aqueous diluent.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Buffered penicillin powder, penicillin powder with buffered aqueous diluent. 520...FORM NEW ANIMAL DRUGS § 520.1696a Buffered penicillin powder, penicillin powder with buffered...

  5. Intracellular Bicarbonate Regulates Action Potential Generation via KCNQ Channel Modulation

    PubMed Central

    Jones, Ryan T.

    2014-01-01

    Bicarbonate (HCO3?) is an abundant anion that regulates extracellular and intracellular pH. Here, we use patch-clamp techniques to assess regulation of hippocampal CA3 pyramidal cell excitability by HCO3? in acute brain slices from C57BL/6 mice. We found that increasing HCO3? levels enhances action potential (AP) generation in both the soma and axon initial segment (AIS) by reducing Kv7/KCNQ channel activity, independent of pH (i.e., at a constant pH of 7.3). Conversely, decreasing intracellular HCO3? leads to attenuation of AP firing. We show that HCO3? interferes with Kv7/KCNQ channel activation by phosphatidylinositol-4,5-biphosphate. Consequently, we propose that, even in the presence of a local depolarizing Cl? gradient, HCO3? efflux through GABAA receptors may ensure the inhibitory effect of axoaxonic cells at the AIS due to activation of Kv7/KCNQ channels. PMID:24647960

  6. Sodium bicarbonate in chemical flooding. Project OE6. [Viscosities of chemical slugs

    SciTech Connect

    Peru, D.A.

    1986-05-01

    In this report we are presenting the results of our investigation in 3 areas: (1) the use of low pH alkaline chemicals for wettability alteration; (2) the development of a correlation between interfacial shear viscosity and water breakout for oil-brine macroemulsions; and (3) the evaluation of bicarbonate as a chemical for use in oil recovery. The main objective of our work is to develop an understanding of the mechanisms involved in bicarbonate flooding and to make specific recommendations for its potential use in enhanced oil recovery. To evaluate the use of bicarbonate as an emulsion destabilizer, emulsification and coalescence test results were compared with interfacial shear viscosities. In two of the three systems studied an inverse relationship was found between the maximum rate of water breakout and interfacial shear viscosity. Temperature and aging of the interface was a major factor affecting these results. Sodium bicarbonate and sodium carbonate were used to determine their effect on rock wettability. Sodium bicarbonate was found to change the wettability of Berea sandstone toward the water-wet state more effectively than sodium carbonate for the low acid oil, Noone crude. Highly acidic crude oils appeared to react with bicarbonate creating highly absorbed surfactants. This caused Berea sandstone to become more oil-wet. The major mechanisms of oil recovery using sodium bicarbonate include wettability alteration, emulsification followed by coalescence, and lowered interfacial shear viscosity. These mechanisms alone did not cause significant recovery of the low acid oil, Noone crude. Previous oil displacement tests indicate that bicarbonate is more effective when using acidic crude oils. The range of oils that can be recovered using bicarbonate can be extended by adding small amounts of surfactants to the bicarbonate slug. 18 refs., 3 figs., 6 tabs.

  7. Storage of Anthropogenic Carbon Dioxide as Ocean Bicarbonate

    NASA Astrophysics Data System (ADS)

    Rau, G. H.; Caldeira, K.

    2006-12-01

    Fossil fuels will likely remain the world's primary energy source for the foreseeable future. Practical and safe means of lowering the associated CO2 emissions are therefore needed to avoid potentially catastrophic climate and environmental impacts. The ocean should not be ignored in assessing both CO2 effects and mitigation options. Accelerated weathering of limestone (AWL) is a candidate technology that could significantly contribute to lowering CO2 emissions as well as to chemically mitigating the effects of ocean acidification. Our research has shown that contacting flue gas (from fossil fuel combustion) with seawater and limestone presents a simple, low-tech way of spontaneously reacting CO2 out of waste gas streams to form a bicarbonate-rich solution via the reaction: CO2 + CaCO3 + H2O <--> Ca2+ + 2HCO3-. (An analogous seawater process is already commercially used in some locations to remove flue gas SOx.) Our modeling studies show that disposing of the resulting calcium bicarbonate-rich solution in the ocean would provide effective, long-term carbon sequestration. It would also add carbonate alkalinity, thus countering the effects of CO2-caused ocean acidification on corals, shellfish, and other calcifying marine organisms. AWL reactors could be optimized for carbon storage or for mitigation of ocean acidification. Experiments have shown that seawater can tolerate >18x saturation before calcium carbonate precipitation is chemically initiated. It is therefore unlikely that once AWL effluent is in the ocean that degassing of some residual CO2 would lead to a reversal of the above reaction and subsequent carbonate precipitation. It is proposed that the cost, safety, impacts, and effectiveness of AWL be further evaluated as a means of mitigating CO2 from point sources, and of reducing the loss of marine calcification.

  8. Partial nitrification in an air-lift reactor with long-term feeding of increasing ammonium concentrations.

    PubMed

    Chai, Li-Yuan; Ali, Mohammad; Min, Xiao-Bo; Song, Yu-Xia; Tang, Chong-Jian; Wang, Hai-Ying; Yu, Cheng; Yang, Zhi-Hui

    2015-06-01

    The partial nitrification (PN) performance under high ammonium concentrations was evaluated in an airlift reactor (ALR). The ALR was operated for 253days with stepwise elevation of ammonium concentration to 1400mg/L corresponding nitrogen loading rate of 2.1kg/m(3)/d. The ammonium removal rate was finally developed to 2.0kg/m(3)/d with average removal efficiency above 91% and nitrite accumulation percentage of 80%. Results showed that the combined effect of limited DO, high bicarbonate, pH and free ammonia (FA) contributed to the stable nitrite accumulation substantially. The biomass in the ALR was improved with the inception of granulation. Precipitates on biomass surface was unexpectedly experienced which might improve the settleability of PN biomass. Organic functional groups attached to the PN biomass suggested the possible absorbability to different types of pollutant. The results provided important evidence for the possibility of applying an ALR to treat high strength ammonium wastewater. PMID:25768415

  9. Ammonium content and buoyancy in midwater cephalopods

    E-print Network

    Thuesen, Erik V.

    Ammonium content and buoyancy in midwater cephalopods Brad A. Seibela,*, Shana K. Goffredib , Erik the cation concentrations in several midwater cephalopod species. High NH4 + levels were confirmed in cephalopods is the exchange of sodium for ammonium ions creating low-density fluids that impart lift (Clarke

  10. Action of ammonium on a chloride pump

    Microsoft Academic Search

    H. Meyer; H. D. Lux

    1974-01-01

    The actions of intra- and extracellularly applied ammonium ions were studied on membrane potentials of the isolated crayfish stretch receptor neuron. In accordance with results obtained from cat spinal motoneurons, ammonium produced a gradual and reversible shift of the IPSP reversal potential towards the resting potential following both kinds of application. In the concentrations tested extracellularly (3 to 15 mM\\/l),

  11. 21 CFR 184.1133 - Ammonium alginate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...alginate (CAS Reg. No. 9005-34-9) is the ammonium salt of alginic acid, a natural polyuronide constituent of certain brown algae. Ammonium alginate is prepared by the neutralization of purified alginic acid with appropriate pH control agents....

  12. 21 CFR 184.1133 - Ammonium alginate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...alginate (CAS Reg. No. 9005-34-9) is the ammonium salt of alginic acid, a natural polyuronide constituent of certain brown algae. Ammonium alginate is prepared by the neutralization of purified alginic acid with appropriate pH control agents....

  13. 21 CFR 184.1133 - Ammonium alginate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...alginate (CAS Reg. No. 9005-34-9) is the ammonium salt of alginic acid, a natural polyuronide constituent of certain brown algae. Ammonium alginate is prepared by the neutralization of purified alginic acid with appropriate pH control agents....

  14. 21 CFR 184.1133 - Ammonium alginate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...alginate (CAS Reg. No. 9005-34-9) is the ammonium salt of alginic acid, a natural polyuronide constituent of certain brown algae. Ammonium alginate is prepared by the neutralization of purified alginic acid with appropriate pH control agents....

  15. 21 CFR 184.1133 - Ammonium alginate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...alginate (CAS Reg. No. 9005-34-9) is the ammonium salt of alginic acid, a natural polyuronide constituent of certain brown algae. Ammonium alginate is prepared by the neutralization of purified alginic acid with appropriate pH control agents....

  16. Biodegradation of rocket propellant waste, ammonium perchlorate

    NASA Technical Reports Server (NTRS)

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

    1975-01-01

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

  17. Phase diagram of ammonium nitrate

    NASA Astrophysics Data System (ADS)

    Dunuwille, Mihindra; Yoo, Choong-Shik

    2013-12-01

    Ammonium Nitrate (AN) is a fertilizer, yet becomes an explosive upon a small addition of chemical impurities. The origin of enhanced chemical sensitivity in impure AN (or AN mixtures) is not well understood, posing significant safety issues in using AN even today. To remedy the situation, we have carried out an extensive study to investigate the phase stability of AN and its mixtures with hexane (ANFO-AN mixed with fuel oil) and Aluminum (Ammonal) at high pressures and temperatures, using diamond anvil cells (DAC) and micro-Raman spectroscopy. The results indicate that pure AN decomposes to N2, N2O, and H2O at the onset of the melt, whereas the mixtures, ANFO and Ammonal, decompose at substantially lower temperatures. The present results also confirm the recently proposed phase IV-IV' transition above 17 GPa and provide new constraints for the melting and phase diagram of AN to 40 GPa and 400°C.

  18. Increased serum triglycerides and reduced HDL cholesterol in male rats after intake of ammonium chloride for 3 weeks

    PubMed Central

    2013-01-01

    Background Previous data suggested that intake of sodas and other acid beverages might be associated with increased levels of serum triglycerides, lowered HDL cholesterol, and increased formation of mono unsaturated fatty acids, which are the preferred ones for triglyceride synthesis. The present work is an extension of these studies. Methods Thirty male rats were divided into 3 groups. All groups were given the same food, but various beverages: water (W), ammonium chloride, 200 mmol/L (AC), or sodium bicarbonate, 200 mmol/L (SB). Serum triglycerides, HDL cholesterol, and the fatty acid distribution in total serum lipids were determined. Delta9-desaturase in serum lipids was estimated by the ratio of palmitoleic to palmitic acid, and by the oleic/stearic acid ratio. Correlation and ANOVA were used to study associations and group differences. Results After 3 weeks, the AC group had higher triglyceride concentration and higher Delta9 desaturase indexes, but lower serum HDL and body weight as compared with the SB and W groups. In each of the groups, the oleic acid/stearic acid ratio correlated positively with serum triglycerides; in the pooled group the correlation coefficient was r?=?0.963, p<0.01. Conclusions Rats ingesting ammonium chloride as compared with sodium bicarbonate responded with increased desaturase indexes, increased serum triglycerides, and lowered HDL cholesterol concentration, thereby possibly contributing to explain the increased triglyceride concentration previously observed in subjects with a frequent intake of acid beverages, such as sodas containing carbonic acid, citric acid, and phosphoric acid. PMID:23800210

  19. Electrodialysis operation with buffer solution

    DOEpatents

    Hryn, John N. (Naperville, IL); Daniels, Edward J. (Orland Park, IL); Krumdick, Greg K. (Crete, IL)

    2009-12-15

    A new method for improving the efficiency of electrodialysis (ED) cells and stacks, in particular those used in chemical synthesis. The process entails adding a buffer solution to the stack for subsequent depletion in the stack during electrolysis. The buffer solution is regenerated continuously after depletion. This buffer process serves to control the hydrogen ion or hydroxide ion concentration so as to protect the active sites of electrodialysis membranes. The process enables electrodialysis processing options for products that are sensitive to pH changes.

  20. The Potential Role of Systemic Buffers in Reducing Intratumoral Extracellular pH and Acid-Mediated Invasion

    PubMed Central

    Silva, Ariosto S.; Yunes, Jose A.; Gillies, Robert J.; Gatenby, Robert A.

    2013-01-01

    A number of studies have shown that the extracellular pH (pHe) in cancers is typically lower than that in normal tissue and that an acidic pHe promotes invasive tumor growth in primary and metastatic cancers. Here, we investigate the hypothesis that increased systemic concentrations of pH buffers reduce intratumoral and peritumoral acidosis and, as a result, inhibit malignant growth. Computer simulations are used to quantify the ability of systemic pH buffers to increase the acidic pHe of tumors in vivo and investigate the chemical specifications of an optimal buffer for such purpose. We show that increased serum concentrations of the sodium bicarbonate (NaHCO3) can be achieved by ingesting amounts that have been used in published clinical trials. Furthermore, we find that consequent reduction of tumor acid concentrations significantly reduces tumor growth and invasion without altering the pH of blood or normal tissues. The simulations also show that the critical parameter governing buffer effectiveness is its pKa. This indicates that NaHCO3, with a pKa of 6.1, is not an ideal intratumoral buffer and that greater intratumoral pHe changes could be obtained using a buffer with a pKa of ~7. The simulations support the hypothesis that systemic pH buffers can be used to increase the tumor pHe and inhibit tumor invasion. PMID:19276380

  1. Effect of ammonium nitrate on precipitation of Ammonium Di-Uranate (ADU) and its characteristics

    NASA Astrophysics Data System (ADS)

    Paik, Shrishma; Biswas, S.; Bhattacharya, S.; Roy, S. B.

    2013-09-01

    Effect of ammonium nitrate on precipitation of Ammonium Di-Uranate (ADU) from nitric acid medium via gaseous ammonia route had been investigated. Studies on effect of ammonium nitrate on precipitation time, particle size, shape, surface morphology, flowability, oxygen/uranium (O/U) ratio and tap density of calcined ADU were carried out at various ammonium nitrate concentrations. It was observed that, the presence of excess ammonium nitrate influences the precipitation time, particle size distribution and surface morphology of the ADU. ADU and uranium oxide were characterized with Scanning Electron Microscopy (SEM) and X-ray diffraction (XRD). Presence of ammonium nitrate during precipitation leads to the formation of bigger, porous and uniform particles as compared to the ADU prepared without ammonium nitrate additions.

  2. The origin of high sodium bicarbonate waters in the Atlantic and Gulf Coastal Plains

    USGS Publications Warehouse

    Foster, M.D.

    1950-01-01

    Some sodium bicarbonate waters at depth in the Atlantic and Gulf Coastal Plains have the same bicarbonate content as the shallower calcium bicarbonate waters in the same formation and appear to be the result of replacement of calcium by sodium through the action of base-exchange minerals. Others, however, contain several hundred parts per million more of bicarbonate than any of the calcium bicarbonate waters and much more bicarbonate than can be attributed to solution of calcium carbonate through the action of carbon dioxide derived from the air and soil. As the waters in the Potomac group (Cretaceous) are all low in sulphate and as the environmental conditions under which the sediments of the Potomac group were deposited do not indicate that large amounts of sulphate are available for solution, it does not seem probable that carbon dioxide generated by chemical or biochemical breakdown of sulphate is responsible for the high sodium bicarbonate waters in this area. Sulphate as a source of oxygen is not necessary for the generation of carbon dioxide by carbonaceous material. Oxygen is an important constituent of carbonaceous material and carbon dioxide is a characteristic decomposition product of such material-as, for example, peat and lignite. Experimental work showed that distilled water, calcium bicarbonate water, and sodium bicarbonate water, after contact with lignite, calcium carbonate, and permutite (a base-exchange material), had all increased greatly in sodium bicarbonate content and had become similar in chemical character and in mineral content to high sodium bicarbonate waters found in the Coastal Plain. The tests indicated that carbonaceous material can act as a source of carbon dioxide, which, when dissolved in water, enables it to take into solution more calcium carbonate. If base-exchange materials are also present to replace calcium with sodium, a still greater amount of bicarbonate can be held in solution. The presence of carbonaceous material, together with calcium carbonate and base-exchange minerals in a formation is, therefore, sufficient to account for the occurrence in it of high sodium bicarbonate waters. ?? 1950.

  3. 40 CFR 721.10302 - Zinc ammonium phosphate (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 2014-07-01 false Zinc ammonium phosphate (generic). 721...Specific Chemical Substances § 721.10302 Zinc ammonium phosphate (generic). ...chemical substance identified generically as zinc ammonium phosphate (PMN...

  4. 40 CFR 721.10302 - Zinc ammonium phosphate (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 2012-07-01 false Zinc ammonium phosphate (generic). 721...Specific Chemical Substances § 721.10302 Zinc ammonium phosphate (generic). ...chemical substance identified generically as zinc ammonium phosphate (PMN...

  5. 40 CFR 721.10302 - Zinc ammonium phosphate (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 2013-07-01 false Zinc ammonium phosphate (generic). 721...Specific Chemical Substances § 721.10302 Zinc ammonium phosphate (generic). ...chemical substance identified generically as zinc ammonium phosphate (PMN...

  6. 78 FR 32690 - Certain Ammonium Nitrate From Ukraine

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-31

    ...Review)] Certain Ammonium Nitrate From Ukraine Determination On the basis of the record...order on certain ammonium nitrate from Ukraine would be likely to lead to continuation...entitled Certain Ammonium Nitrate from Ukraine: Investigation No....

  7. 21 CFR 172.165 - Quaternary ammonium chloride combination.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2009-04-01 true Quaternary ammonium chloride combination. 172.165 ...Preservatives § 172.165 Quaternary ammonium chloride combination. The food additive, quaternary ammonium chloride combination, may be...

  8. 40 CFR 721.10511 - Quaternary ammonium salts (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false Quaternary ammonium salts (generic). 721.10511 Section 721...Substances § 721.10511 Quaternary ammonium salts (generic). (a) Chemical substance...identified generically as quaternary ammonium salts (PMNs P-07-320,...

  9. 21 CFR 182.1127 - Aluminum ammonium sulfate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Aluminum ammonium sulfate. 182.1127 Section...Purpose GRAS Food Substances § 182.1127 Aluminum ammonium sulfate. (a) Product. Aluminum ammonium sulfate. (b) Conditions...

  10. 21 CFR 582.1127 - Aluminum ammonium sulfate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 2014-04-01 false Aluminum ammonium sulfate. 582.1127 Section...General Purpose Food Additives § 582.1127 Aluminum ammonium sulfate. (a) Product. Aluminum ammonium sulfate. (b) Conditions...

  11. 21 CFR 182.1127 - Aluminum ammonium sulfate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 2010-04-01 2009-04-01 true Aluminum ammonium sulfate. 182.1127 Section...Purpose GRAS Food Substances § 182.1127 Aluminum ammonium sulfate. (a) Product. Aluminum ammonium sulfate. (b) Conditions...

  12. 21 CFR 582.1127 - Aluminum ammonium sulfate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Aluminum ammonium sulfate. 582.1127 Section...General Purpose Food Additives § 582.1127 Aluminum ammonium sulfate. (a) Product. Aluminum ammonium sulfate. (b) Conditions...

  13. 21 CFR 582.1127 - Aluminum ammonium sulfate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Aluminum ammonium sulfate. 582.1127 Section...General Purpose Food Additives § 582.1127 Aluminum ammonium sulfate. (a) Product. Aluminum ammonium sulfate. (b) Conditions...

  14. 21 CFR 582.1127 - Aluminum ammonium sulfate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false Aluminum ammonium sulfate. 582.1127 Section...General Purpose Food Additives § 582.1127 Aluminum ammonium sulfate. (a) Product. Aluminum ammonium sulfate. (b) Conditions...

  15. 21 CFR 582.1127 - Aluminum ammonium sulfate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 2012-04-01 false Aluminum ammonium sulfate. 582.1127 Section...General Purpose Food Additives § 582.1127 Aluminum ammonium sulfate. (a) Product. Aluminum ammonium sulfate. (b) Conditions...

  16. 21 CFR 182.1127 - Aluminum ammonium sulfate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 2014-04-01 false Aluminum ammonium sulfate. 182.1127 Section...Purpose GRAS Food Substances § 182.1127 Aluminum ammonium sulfate. (a) Product. Aluminum ammonium sulfate. (b) Conditions...

  17. 21 CFR 182.1127 - Aluminum ammonium sulfate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 2012-04-01 false Aluminum ammonium sulfate. 182.1127 Section...Purpose GRAS Food Substances § 182.1127 Aluminum ammonium sulfate. (a) Product. Aluminum ammonium sulfate. (b) Conditions...

  18. 21 CFR 182.1127 - Aluminum ammonium sulfate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false Aluminum ammonium sulfate. 182.1127 Section...Purpose GRAS Food Substances § 182.1127 Aluminum ammonium sulfate. (a) Product. Aluminum ammonium sulfate. (b) Conditions...

  19. 21 CFR 184.1141a - Ammonium phosphate, monobasic.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Ammonium phosphate, monobasic. 184.1141a Section 184...Affirmed as GRAS § 184.1141a Ammonium phosphate, monobasic. (a) Ammonium phosphate, monobasic (NH4 H2 PO4 , CAS...

  20. ZnS/Zn(O,OH)S-based buffer layer deposition for solar cells

    DOEpatents

    Bhattacharya, Raghu N. (Littleton, CO)

    2009-11-03

    The invention provides CBD ZnS/Zn(O,OH)S and spray deposited ZnS/Zn(O,OH)S buffer layers prepared from a solution of zinc salt, thiourea and ammonium hydroxide dissolved in a non-aqueous/aqueous solvent mixture or in 100% non-aqueous solvent. Non-aqueous solvents useful in the invention include methanol, isopropanol and triethyl-amine. One-step deposition procedures are described for CIS, CIGS and other solar cell devices.

  1. Regulatory mechanism underlying cyclic changes in mouse uterine bicarbonate secretion: role of estrogen.

    PubMed

    He, Qiong; Chen, Hui; Wong, Connie Hau Yan; Tsang, Lai Ling; Chan, Hsiao Chang

    2010-12-01

    Our previous study has demonstrated that bicarbonate in the uterine fluid plays an indispensable role in sperm capacitation. However, the cellular mechanisms underlying the formation of bicarbonate-rich uterine fluid and the regulatory mechanism remained largely unknown. In this study, the expression profiles of bicarbonate transport/production proteins, the cystic fibrosis transmembrane conductance regulator (CFTR), SLC26A6, carbonic anhydrase 2 (CAR2, CA2) and CAR12 (CA12), throughout the estrous cycle, were examined in the mouse uterus by western blot. The results showed that the maximum expression levels of the proteins examined were observed at estrus. Luminal surface pH measurements showed that the resting uterine surface pH at estrus was significantly higher than that at diestrus, which could be reduced significantly by CFTR blocker, diphenylamine-2,2'-dicarboxylic acid, SLC26A6 inhibitor, 4',4'-diisothiocyanostilbene-2',2'-disulfonic acid, and CA inhibitor, acetazolamide. In ovariectomized mice and primary culture of endometrial epithelial cells, estrogen could upregulate CFTR, SLC26A6, CAR2, and CAR12 expression with a corresponding increase in the bicarbonate-dependent short-circuit current (I(sc)) and endometrial surface pH. The present results have demonstrated dynamic changes in uterine bicarbonate secretion and expression of the proteins involved in bicarbonate secretion during the estrous cycle and suggested a novel role of estrogen in regulating uterine bicarbonate transport, which may be important for successful reproduction. PMID:20876742

  2. 40 CFR 180.473 - Glufosinate ammonium; tolerances for residues.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...glufosinate-ammonium (butanoic acid, 2-amino-4-(hydroxymethylphosphinyl...3-methylphosphinico-propionic acid, expressed as 2-amino-4-(hydroxymethylphosphinyl...glufosinate ammonium, butanoic acid,...

  3. 40 CFR 180.473 - Glufosinate ammonium; tolerances for residues.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...glufosinate ammonium, butanoic acid, 2-amino-4-(hydroxymethylphosphinyl...hydroxymethylphosphinyl)propanoic acid, expressed as 2-amino-4-(hydroxymethylphosphinyl...glufosinate ammonium, butanoic acid,...

  4. 40 CFR 180.473 - Glufosinate ammonium; tolerances for residues.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...glufosinate ammonium, butanoic acid, 2-amino-4-(hydroxymethylphosphinyl...hydroxymethylphosphinyl)propanoic acid, expressed as 2-amino-4-(hydroxymethylphosphinyl...glufosinate ammonium, butanoic acid,...

  5. Glyphosate detection with ammonium nitrate and humic acids as potential interfering substances by pulsed voltammetry technique.

    PubMed

    Martínez Gil, Pablo; Laguarda-Miro, Nicolas; Camino, Juan Soto; Peris, Rafael Masot

    2013-10-15

    Pulsed voltammetry has been used to detect and quantify glyphosate on buffered water in presence of ammonium nitrate and humic substances. Glyphosate is the most widely used herbicide active ingredient in the world. It is a non-selective broad spectrum herbicide but some of its health and environmental effects are still being discussed. Nowadays, glyphosate pollution in water is being monitored but quantification techniques are slow and expensive. Glyphosate wastes are often detected in countryside water bodies where organic substances and fertilizers (commonly based on ammonium nitrate) may also be present. Glyphosate also forms complexes with humic acids so these compounds have also been taken into consideration. The objective of this research is to study the interference of these common pollutants in glyphosate measurements by pulsed voltammetry. The statistical treatment of the voltammetric data obtained lets us discriminate glyphosate from the other studied compounds and a mathematical model has been built to quantify glyphosate concentrations in a buffer despite the presence of humic substances and ammonium nitrate. In this model, the coefficient of determination (R(2)) is 0.977 and the RMSEP value is 2.96 × 10(-5) so the model is considered statistically valid. PMID:24054650

  6. Free flow cell electrophoresis using zwitterionic buffer

    NASA Technical Reports Server (NTRS)

    Rodkey, R. Scott

    1990-01-01

    Studies of a zwitterionic buffer formulated for cell electrophoresis were done using the McDonnell-Douglas Continuous Flow Electrophoresis System. Standard buffers were analyzed for their stability in the electrical field and the results showed that both buffers tested were inherently unstable. Further, titration studies showed that the standards buffers buffered poorly at the pH employed for electrophoresis. The zwitterionic buffer buffered well at its nominal pH and was shown to be stable in the electrical field. Comparative studies of the buffer with standard cell separation buffers using formalin fixed rabbit and goose red blood cells showed that the zwitterionic buffer gave better resolution of the fixed cells. Studies with viable hybridoma cells showed that buffer Q supported cell viability equal to Hank's Balanced Salt Solution and that hybridoma cells in different stages of the growth cycle demonstrated reproducible differences in electrophoretic mobility.

  7. Bicarbonate impact on U(VI) bioreduction in a shallow alluvial aquifer

    NASA Astrophysics Data System (ADS)

    Long, Philip E.; Williams, Kenneth H.; Davis, James A.; Fox, Patricia M.; Wilkins, Michael J.; Yabusaki, Steven B.; Fang, Yilin; Waichler, Scott R.; Berman, Elena S. F.; Gupta, Manish; Chandler, Darrell P.; Murray, Chris; Peacock, Aaron D.; Giloteaux, Ludovic; Handley, Kim M.; Lovley, Derek R.; Banfield, Jillian F.

    2015-02-01

    Field-scale biostimulation and desorption tracer experiments conducted in a uranium (U) contaminated, shallow alluvial aquifer have provided insight into the coupling of microbiology, biogeochemistry, and hydrogeology that control U mobility in the subsurface. Initial experiments successfully tested the concept that Fe-reducing bacteria such as Geobacter sp. could enzymatically reduce soluble U(VI) to insoluble U(IV) during in situ electron donor amendment (Anderson et al., 2003; Williams et al., 2011). In parallel, in situ desorption tracer tests using bicarbonate amendment demonstrated rate-limited U(VI) desorption (Fox et al., 2012). These results and prior laboratory studies underscored the importance of enzymatic U(VI)-reduction and suggested the ability to combine desorption and bioreduction of U(VI). Here we report the results of a new field experiment in which bicarbonate-promoted uranium desorption and acetate amendment were combined and compared to an acetate amendment-only experiment in the same experimental plot. Results confirm that bicarbonate amendment to alluvial aquifer sediments desorbs U(VI) and increases the abundance of Ca-uranyl-carbonato complexes. At the same time, the rate of acetate-promoted enzymatic U(VI) reduction was greater in the presence of added bicarbonate in spite of the increased dominance of Ca-uranyl-carbonato aqueous complexes. A model-simulated peak rate of U(VI) reduction was ?3.8 times higher during acetate-bicarbonate treatment than under acetate-only conditions. Lack of consistent differences in microbial community structure between acetate-bicarbonate and acetate-only treatments suggest that a significantly higher rate of U(VI) reduction in the bicarbonate-impacted sediment may be due to a higher intrinsic rate of microbial reduction induced by elevated concentrations of the bicarbonate oxyanion. The findings indicate that bicarbonate amendment may be useful in improving the engineered bioremediation of uranium in aquifers.

  8. Sample Buffer: ReservoirVolume

    E-print Network

    Gaudet, Rachelle

    chloride hydrate Multivalent 3. (A3) 0.1 M Calcium chloride dihydrate Multivalent 4. (A4) 0.1 M Cobalt hexahydrate Multivalent 14. (B2) 0.1 M Praseodymium(III) acetate hydrate Multivalent 15. (B3) 1.0 M Ammonium

  9. Microbially mediated clinoptilolite regeneration in a multifunctional permeable reactive barrier used to remove ammonium from landfill leachate contamination: laboratory column evaluation.

    PubMed

    Nooten, Thomas Van; Diels, Ludo; Bastiaens, Leen

    2010-05-01

    This study focuses on multifunctional permeable reactive barrier (multibarrier) technology, combining microbial degradation and abiotic ion exchange processes for removal of ammonium from landfill leachate contamination. The sequential multibarrier concept relies on the use of a clinoptilolite-filled buffer compartment to ensure a robust ammonium removal in case of temporary insufficient microbial activities. An innovative strategy was developed to allow in situ clinoptilolite regeneration. Laboratory-scale clinoptilolite-filled columns were first saturated with ammonium, using real landfill leachate as well as synthetic leachates as feed media. Other inorganic metal cations, typically present in landfill leachate, had a detrimental influence on the ammonium removal capacity by competing for clinoptilolite exchange sites. On the other hand, the metals had a highly favorable impact on regeneration of the saturated material. Feeding the columns with leachate deprived from ammonium (e.g., by microbial nitrification in an upgradient compartment), resulted in a complete release of the previously sorbed ammonium from the clinoptilolite, due to exchange with metal cations present in the leachate. The released ammonium is then available for microbial consumption in a downgradient compartment. The regeneration process resulted in a slightly increased ammonium exchange capacity afterward. The described strategy throws a new light on sustainable use of sorption materials for in situ groundwater remediation, by avoiding the need for material replacement and the use of external chemical regenerants. PMID:20387879

  10. Phase diagram of ammonium nitrate

    SciTech Connect

    Dunuwille, Mihindra; Yoo, Choong-Shik, E-mail: csyoo@wsu.edu [Department of Chemistry and Institute for Shock Physics, Washington State University, Pullman, Washington 99164 (United States)] [Department of Chemistry and Institute for Shock Physics, Washington State University, Pullman, Washington 99164 (United States)

    2013-12-07

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

  11. Buffer Gas Acquisition and Storage

    NASA Technical Reports Server (NTRS)

    Parrish, Clyde F.; Lueck, Dale E.; Jennings, Paul A.; Callahan, Richard A.; Delgado, H. (Technical Monitor)

    2001-01-01

    The acquisition and storage of buffer gases (primarily argon and nitrogen) from the Mars atmosphere provides a valuable resource for blanketing and pressurizing fuel tanks and as a buffer gas for breathing air for manned missions. During the acquisition of carbon dioxide (CO2), whether by sorption bed or cryo-freezer, the accompanying buffer gases build up in the carbon dioxide acquisition system, reduce the flow of CO2 to the bed, and lower system efficiency. It is this build up of buffer gases that provide a convenient source, which must be removed, for efficient capture Of CO2 Removal of this buffer gas barrier greatly improves the charging rate of the CO2 acquisition bed and, thereby, maintains the fuel production rates required for a successful mission. Consequently, the acquisition, purification, and storage of these buffer gases are important goals of ISRU plans. Purity of the buffer gases is a concern e.g., if the CO, freezer operates at 140 K, the composition of the inert gas would be approximately 21 percent CO2, 50 percent nitrogen, and 29 percent argon. Although there are several approaches that could be used, this effort focused on a hollow-fiber membrane (HFM) separation method. This study measured the permeation rates of CO2, nitrogen (ND, and argon (Ar) through a multiple-membrane system and the individual membranes from room temperature to 193K and 10 kpa to 300 kPa. Concentrations were measured with a gas chromatograph that used a thermoconductivity (TCD) detector with helium (He) as the carrier gas. The general trend as the temperature was lowered was for the membranes to become more selective, In addition, the relative permeation rates between the three gases changed with temperature. The end result was to provide design parameters that could be used to separate CO2 from N2 and Ar.

  12. Buffer gas acquisition and storage

    NASA Astrophysics Data System (ADS)

    Parrish, Clyde F.; Lueck, Dale E.; Jennings, Paul A.

    2001-02-01

    The acquisition and storage of buffer gases (primarily argon and nitrogen) from the Mars atmosphere provides a valuable resource for blanketing and pressurizing fuel tanks and as a buffer gas for breathing air for manned missions. During the acquisition of carbon dioxide (CO2), whether by sorption bed or cryo-freezer, the accompanying buffer gases build up in the carbon dioxide acquisition system, reduce the flow of CO2 to the bed, and lower system efficiency. It is this build up of buffer gases that provide a convenient source, which must be removed, for efficient capture of CO2. Removal of this buffer gas barrier greatly improves the charging rate of the CO2 acquisition bed and, thereby, maintains the fuel production rates required for a successful mission. Consequently, the acquisition, purification, and storage of these buffer gases are important goals of ISRU plans. Purity of the buffer gases is a concern e.g., if the CO2 freezer operates at 140 K, the composition of the inert gas would be approximately 21 percent CO2, 50 percent nitrogen, and 29 percent argon. Although there are several approaches that could be used, this effort focused on a hollow-fiber membrane (HFM) separation method. This study measured the permeation rates of CO2, nitrogen (N2), and argon (Ar) through a multiple-membrane system and the individual membranes from room temperature to 193 K and 10 kPa to 300 kPa. Concentrations were measured with a gas chromatograph. The end result was data necessary to design a system that could separate CO2, N2, and Ar. .

  13. Analysis of drugs of forensic interest with capillary zone electrophoresis/time-of-flight mass spectrometry based on the use of non-volatile buffers.

    PubMed

    Gottardo, Rossella; Mikšík, Ivan; Aturki, Zeineb; Sorio, Daniela; Seri, Catia; Fanali, Salvatore; Tagliaro, Franco

    2012-02-01

    The present work is aimed at investigating the influence of the background electrolyte composition and concentration on the separation efficiency and resolution and mass spectrometric detection of illicit drugs in a capillary zone electrophoresis-electrospray ionization-time of flight mass spectrometry (CZE-ESI-TOF MS) system. The effect of phosphate, borate and Tris buffers on the separation and mass spectrometry response of a mixture of 3,4-methylenedioxyamphetamine, 3,4-methylenedioxymethamphetamine, methadone, cocaine, morphine, codeine and 6-monoacetylmorphine was studied, in comparison with a reference ammonium formate separation buffer. Inorganic non-volatile borate and Tris buffers proved hardly suitable for capillary electrophoresis-mass spectrometry (CE-MS) analysis, but quite unexpectedly ammonium phosphate buffers showed good separation and ionization performances for all the analytes tested. Applications of this method to real samples of hair from drug addicts are also provided. PMID:22451052

  14. A Bicarbonate Cofactor Modulates 1,4-Dihydroxy-2-naphthoyl-Coenzyme A Synthase in Menaquinone Biosynthesis of Escherichia coli*

    PubMed Central

    Jiang, Ming; Chen, Minjiao; Guo, Zu-Feng; Guo, Zhihong

    2010-01-01

    1,4-Dihydroxy-2-naphthoyl coenzyme A (DHNA-CoA) synthase is a typical crotonase-fold protein catalyzing an intramolecular Claisen condensation in the menaquinone biosynthetic pathway. We have characterized this enzyme from Escherichia coli and found that it is activated by bicarbonate in a concentration-dependent manner. The bicarbonate binding site has been identified in the crystal structure of a virtually identical ortholog (96.8% sequence identity) from Salmonella typhimurium through comparison with a bicarbonate-insensitive orthologue. Kinetic properties of the enzyme and its site-directed mutants of the bicarbonate binding site indicate that the exogenous bicarbonate anion is essential to the enzyme activity. With this essential catalytic role, the simple bicarbonate anion is an enzyme cofactor, which is usually a small organic molecule derived from vitamins, a metal ion, or a metal-containing polyatomic anionic complex. This finding leads to classification of the DHNA-CoA synthases into two evolutionarily conserved subfamilies: type I enzymes that are bicarbonate-dependent and contain a conserved glycine at the bicarbonate binding site; and type II enzymes that are bicarbonate-independent and contain a conserved aspartate at the position similar to the enzyme-bound bicarbonate. In addition, the unique location of the enzyme-bound bicarbonate allows it to be proposed as a catalytic base responsible for abstraction of the ?-proton of the thioester substrate in the enzymatic reaction, suggesting a unified catalytic mechanism for all DHNA-CoA synthases. PMID:20643650

  15. Hydrolysis of p-nitrophenyl esters promoted by semifluorinated quaternary ammonium polymer latexes and films.

    PubMed

    Kaur, Baljinder; McBride, Sean P; Paul, Abhijit; Ford, Warren T

    2010-10-19

    Semifluorinated polymer latexes were prepared by emulsion polymerization of 2.5-25% of a fluoroalkyl methacrylate, 25% chloromethylstyrene, 1% styrylmethyl(trimethyl)ammonium chloride, and the remainder 2-ethylhexyl methacrylate under surfactant-free conditions. The chloromethylstyrene units were converted to quaternary ammonium ions with trimethylamine. In aqueous dispersions at particle concentrations of less than 1 mg mL(-1) the quaternary ammonium ion latexes promoted hydrolyses of p-nitrophenyl hexanoate (PNPH) in pH 9.4 borate buffer and of diethyl p-nitrophenyl phosphate (Paraoxon) in 0.1 M NaOH at 30 °C with half-lives of less than 10 min. Thin 0.7-2 ?m films of the latexes on glass promoted fast hydrolysis of Paraoxon but not of PNPH under the same conditions. Even after annealing the quaternary ammonium ion polymer films at temperatures well above their glass transition temperatures, AFM images of the film surfaces had textures of particles. Contact angle measurements of the annealed films against water and against hexadecane showed that the surfaces were not highly fluorinated. PMID:20857956

  16. Bicarbonate of soda paint stripping process validation and material characterization

    NASA Technical Reports Server (NTRS)

    Haas, Michael N.

    1995-01-01

    The Aircraft Production Division at San Antonio Air Logistics Center has conducted extensive investigation into the replacement of hazardous chemicals in aircraft component cleaning, degreasing, and depainting. One of the most viable solutions is process substitution utilizing abrasive techniques. SA-ALC has incorporated the use of Bicarbonate of Soda Blasting as one such substitution. Previous utilization of methylene chloride based chemical strippers and carbon removal agents has been replaced by a walk-in blast booth in which we remove carbon from engine nozzles and various gas turbine engine parts, depaint cowlings, and perform various other functions on a variety of parts. Prior to implementation of this new process, validation of the process was performed, and materials and waste stream characterization studies were conducted. These characterization studies examined the effects of the blasting process on the integrity of the thin-skinned aluminum substrates, the effects of the process on both air emissions and effluent disposal, and the effects on the personnel exposed to the process.

  17. Central angiotensin II induces sodium bicarbonate intake in the rat.

    PubMed

    David, Richard B; Menani, José V; De Luca, Laurival A

    2008-07-01

    The aim of this work was to test mineral preference in hydrated rats that received a pulse intracerebroventricular (icv(p)) injection of ANG II at a dipsogenic dose (50 ng). The icv(p) ANG II induced a four-fold higher ingestion of 0.15M NaHCO(3) than of other mineral solutions at palatable concentrations (0.15M NaCl, 0.05 mM CaCl(2) and 0.01 M KCl) in a five-bottle test with water available in a fifth bottle; water intake was not consistently high in this test. Contrary to what is predicted by the mineralocorticoid/angiotensin II synergy hypothesis, the 0.15M NaCl intake in the five-bottle test was not enhanced by icv(p) ANG II preceded by deoxycorticosterone (DOCA) treatment (2.5mg/day for 3 days); neither was the NaHCO(3) intake. This result contrasted with the vigorous ingestion of both isotonic sodium solutions, but mostly of NaCl, rather than of other fluids, by sodium-depleted (furosemide 10mg sc+24h removal ambient sodium) rats in a sodium appetite test. The results suggest that mineralocorticoid combined to icv(p) ANG II does not simulate the sodium preference shown during sodium appetite. The results also show that a dipsogenic dose of central ANG II induces a reliable ingestion of isotonic sodium bicarbonate in the rat. PMID:18272252

  18. 77 FR 59106 - Glufosinate Ammonium; Pesticide Tolerances

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-26

    ...subchronic study were increased liver and kidney weights with increases in serum aspartate amino transferase and alkaline phosphatase. Additional toxicity testing was conducted with the L-isomer of glufosinate ammonium, and degradates...

  19. Biodegradation of rocket propellent waste, ammonium perchlorate

    NASA Technical Reports Server (NTRS)

    Naqui, S. M. Z.

    1975-01-01

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

  20. 21 CFR 184.1143 - Ammonium sulfate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...sulfate ((NH4 )2 SO4 , CAS Reg. No. 7783-20-2) occurs naturally and consists of colorless or white, odorless crystals or granules. It is prepared by the neutralization of sulfuric acid with ammonium hydroxide. (b) The...

  1. Capillary electrophoresis–electrospray ionization mass spectrometry using uncoated fused-silica capillaries and alkaline buffer solution for the analysis of small carboxylic acids

    Microsoft Academic Search

    Hirokazu Sawada; Chika Nogami

    2004-01-01

    A simple and cost-effective capillary electrophoresis\\/mass spectrometric (CE\\/MS) method for the analysis of small carboxylic acids including succinate, malate, tartarate, maleinate and citrate, is described. All CE\\/MS experiments were performed with uncoated fused-silica capillaries and with alkaline volatile buffer solution (ammonium formate buffer, pH 10). Since sheath liquids have significant effects on the sensitivity in typical CE\\/MS applications, the effects

  2. Stress corrosion cracking of X-60 line pipe steel in a carbonate-bicarbonate solution

    SciTech Connect

    Pilkey, A.K.; Lambert, S.B.; Plumtree, A. (Univ. of Waterloo, Ontario (Canada). Dept. of Mechanical Engineering)

    1995-02-01

    An experimental system was developed to reproduce stress corrosion cracking (SCC) of API X-60 line pipe steels in highly alkaline (pH = 10) carbonate-bicarbonate (1 N sodium carbonate [Na[sub 2]CO[sub 3

  3. The Structure and Spectroscopy of Cyanate and Bicarbonate Ions. Astrophysical Implications

    NASA Astrophysics Data System (ADS)

    Moreno, M. A.; Maté, B.; Rodríguez-Lazcano, Y.; Gálvez, O.; Gómez, P. C.; Herrero, V. J.; Escribano, R.

    2013-10-01

    Cyanate and bicarbonate are two ions that play active roles in many fields of physics and chemistry, including biological sciences and astrochemistry. We present here a comprehensive study of these species covering a range of phases and methodologies. We have performed theoretical calculations on the isolated ions and their hydrates with one to four water molecules, and in clusters with 15 water molecules. The predicted infrared spectra are compared with observed spectra from experiments where liquid droplets of their solutions are frozen at 14 K on a substrate, to mimic some astrophysical conditions. Crystals of cyanate and bicarbonate sodium and potassium salts are also studied experimental and theoretically. As well, the spontaneous decomposition of cyanate into bicarbonate is documented from the spectra of an aged solution. Finally, the possible astrophysical observation of bicarbonate in water-containing particles is discussed.

  4. Photosystem II and the unique role of bicarbonate: A historical perspective Dmitriy Shevela a,

    E-print Network

    Govindjee

    and plants fix carbon dioxide (CO2) into carbohydrates; this is necessary to support life on Earth. Over 50, discovered that there was a definite bicarbonate effect on the electron acceptor (the plastoquinone) side

  5. Relative importance of pancreatic, hepatic, and mucosal bicarbonate in duodenal neutralization of acid in anaesthetized pigs.

    PubMed

    Ainsworth, M A; Svendsen, P; Ladegaard, L; Cantor, P; Olsen, O; Schaffalitzky de Muckadell, O B

    1992-05-01

    Pancreatic and hepatic bicarbonate secretion and the disappearance rate of acid during duodenal acidification were measured simultaneously in anaesthetized pigs. Perfusion of the duodenum with HCl resulted in an increase in both hepatic and pancreatic bicarbonate secretion. During all acid loads hepatic bicarbonate secretion was significantly greater than pancreatic secretion. Furthermore, the disappearance rate of acid in the duodenum during diversion of both bile and pancreatic juice was significantly greater than the amount of acid which could be neutralized by the concomitant pancreatic bicarbonate secretion. Diversion of pancreatic juice from the duodenum did not affect the disappearance rate of acid at any acid load, whereas diversion of bile caused a significant decrease. Thus, in the anaesthetized pig the liver and the duodenal mucosa are of greater importance than the pancreas for the neutralization of acid in the duodenum. It is suggested that the importance of the pancreatic contribution to duodenal neutralization should be reevaluated in other species, including man. PMID:1529266

  6. Remediation of uranium contaminated soils with bicarbonate extraction and microbial U(VI) reduction

    Microsoft Academic Search

    Elizabeth J. P. Phillips; Edward R. Landa; Derek R. Lovley

    1995-01-01

    Summary A process for concentrating uranium from contaminated soils in which the uranium is first extracted with bicarbonate and then the extracted uranium is precipitated with U(VI)-reducing microorganisms was evaluated for a variety of uranuum-contaminated soils. Bicarbonate (100 mM) extracted 20–94% of the uranium that was extracted with nitric acid. The U(VI)-reducing microorganism,Desulfovibrio desulfuricans reduced the U(VI) to U(IV) in

  7. Rheogenic sodium-bicarbonate cotransport in the peritubular cell membrane of rat renal proximal tubule

    Microsoft Academic Search

    K. Yoshitomi; B.-Ch. Burckhardt; E. Frömter

    1985-01-01

    The mechanism of bicarbonate transport across the peritubular cell membrane was investigated in rat kidney proximal tubules in situ by measuring cell pH and cell Na+ activity in response to sudden reduction of peritubular Na+ and\\/or HCO3-. The following observations were made: 1. sudden peritubular reduction of either ion concentration produced the same transient depolarizing potential response; 2. bicarbonate efflux

  8. Effect of chilling, polyphosphate and bicarbonate on quality characteristics of broiler breast meat

    Microsoft Academic Search

    A. R. Sen; B. M. Naveena; M. Muthukumar; Y. Babji; T. R. K. Murthy

    2005-01-01

    1. An experiment was conducted to assess the effect of tetrasodium pyrophosphate and sodium bicarbonate on colour and sensory attributes of pre- and post-chilled breast meat.2. Three groups of 6 halves of breasts (pre-chill) immediately after slaughter were treated with 3% tetrasodium pyrophosphate, 3% sodium bicarbonate in 2% NaCl or 2% NaCl alone (control); the remaining 6 halves (post-chill) were

  9. Acetate and Bicarbonate Assimilation and Metabolite Formation in Chlamydomonas reinhardtii: A 13C-NMR Study

    PubMed Central

    Singh, Himanshu; Shukla, Manish R.; Chary, Kandala V. R.; Rao, Basuthkar J.

    2014-01-01

    Cellular metabolite analyses by 13C-NMR showed that C. reinhardtii cells assimilate acetate at a faster rate in heterotrophy than in mixotrophy. While heterotrophic cells produced bicarbonate and CO2aq, mixotrophy cells produced bicarbonate alone as predominant metabolite. Experiments with singly 13C-labelled acetate (13CH3-COOH or CH3-13COOH) supported that both the 13C nuclei give rise to bicarbonate and CO2aq. The observed metabolite(s) upon further incubation led to the production of starch and triacylglycerol (TAG) in mixotrophy, whereas in heterotrophy the TAG production was minimal with substantial accumulation of glycerol and starch. Prolonged incubation up to eight days, without the addition of fresh acetate, led to an increased TAG production at the expense of bicarbonate, akin to that of nitrogen-starvation. However, such TAG production was substantially high in mixotrophy as compared to that in heterotrophy. Addition of mitochondrial un-coupler blocked the formation of bicarbonate and CO2aq in heterotrophic cells, even though acetate uptake ensued. Addition of PSII-inhibitor to mixotrophic cells resulted in partial conversion of bicarbonate into CO2aq, which were found to be in equilibrium. In an independent experiment, we have monitored assimilation of bicarbonate via photoautotrophy and found that the cells indeed produce starch and TAG at a much faster rate as compared to that in mixotrophy and heterotrophy. Further, we noticed that the accumulation of starch is relatively more as compared to TAG. Based on these observations, we suggest that acetate assimilation in C. reinhardtii does not directly lead to TAG formation but via bicarbonate/CO2aq pathways. Photoautotrophic mode is found to be the best growth condition for the production of starch and TAG and starch in C. reinhardtii. PMID:25207648

  10. Effects of buffer layer structure on polysilicon buffer LOCOS for the isolation of submicron silicon devices

    Microsoft Academic Search

    Jong-Ho Lee; Jong-Son Lyu; Tae Moon Roh; Bo Woo Kim

    1998-01-01

    The effects of a buffer layer structure on polysilicon buffered LOCOS were shown and analyzed. Sample wafers are classified into four groups to show the effect of the buffer layer structure. The structures of the four different buffer layers are monolayer polysilicon (typical), monolayer amorphous silicon (?-Si), double layer ?-Si, and triple layer ?-Si. Total buffer layer thickness of each

  11. Evaporation of Ammonium Nitrate Aerosol in a Heated Nephelometer

    E-print Network

    hygroscopic inorganic salts (i.e., ammonium sulfate, ammonium nitrate) which increase in size with increasingEvaporation of Ammonium Nitrate Aerosol in a Heated Nephelometer: Implications for Field National Laboratory, Upon, New York, 11973-5000 Ammonium nitrate is a semivolatile aerosol component under

  12. The Structure of a Cyanobacterial Bicarbonate Transport Protein, CmpA

    SciTech Connect

    Koropatkin, Nicole M.; Koppenaal, David W.; Pakrasi, Himadri B.; Smith, Thomas J.

    2007-01-26

    Cyanobacteria, blue-green algae, are the most abundant autotrophs in aquatic environments and form the base of the food chain by fixing carbon and nitrogen into cellular biomass. To compensate for the low selectivity of Rubisco for CO? over O?, Cyanobacteria have developed highly efficient CO?concentrating machinery of which the ABC transport system CmpABCD from Synechocystis PCC 6803 is one component. Here we describe the structure of the bicarbonate binding protein, CmpA, in the absence and presence of bicarbonate and carbonic acid. CmpA is highly homologous to the nitrate transport protein, NrtA. CmpA binds carbonic acid at the entrance to the ligand-binding pocket whereas bicarbonate binds in nearly an identical location compared to nitrate binding to NrtA. Unexpectedly, bicarbonate binding is accompanied by a metal ion, identified as Ca²? via inductively coupled plasma optical emission spectrometry. The binding of bicarbonate and metal is highly cooperative and suggests that CmpA co-transports bicarbonate and calcium.

  13. Photosynthetic Utilization of Bicarbonate in Zostera marina Is Reduced by Inhibitors of Mitochondrial ATPase and Electron Transport1

    PubMed Central

    Carr, Herman; Axelsson, Lennart

    2008-01-01

    When Zostera marina was irradiated after a period of darkness, initiation of photosynthetic O2 evolution occurred in two phases. During a lag phase, lasting 4 to 5 min, photosynthesis was supported by a diffusive entry of CO2. Photosynthesis then rapidly increased to its full rate. Tris buffer, at a concentration of 50 mm, completely inhibited this increase without affecting CO2-supported photosynthesis during the lag phase. These results verify that the increase in photosynthesis after the lag phase depended on an activation of bicarbonate (HCO3?) utilization through acid zones generated by proton pumps located to the outer cell membrane. In similar experiments, 6.25 ?m of the mitochondrial ATPase blocker oligomycin inhibited photosynthetic HCO3? utilization by more than 60%. Antimycin A, a selective blocker of mitochondrial electron transport, caused a similar inhibition of HCO3? utilization. Measurements at elevated CO2 concentrations verified that neither oligomycin nor antimycin interfered with linear photosynthetic electron transport or with CO2 fixation. Thus, a major part of the ATP used for the generation of acid zones involved in HCO3? utilization in Z. marina was derived from mitochondrial respiration. PMID:18434609

  14. Bicarbonate Increases Tumor pH and Inhibits Spontaneous Metastases

    PubMed Central

    Robey, Ian F.; Baggett, Brenda K.; Kirkpatrick, Nathaniel D.; Roe, Denise J.; Dosescu, Julie; Sloane, Bonnie F.; Hashim, Arig Ibrahim; Morse, David L.; Raghunand, Natarajan; Gatenby, Robert A.; Gillies, Robert J.

    2010-01-01

    The external pH of solid tumors is acidic as a consequence of increased metabolism of glucose and poor perfusion. Acid pH has been shown to stimulate tumor cell invasion and metastasis in vitro and in cells before tail vein injection in vivo. The present study investigates whether inhibition of this tumor acidity will reduce the incidence of in vivo metastases. Here, we show that oral NaHCO3 selectively increased the pH of tumors and reduced the formation of spontaneous metastases in mouse models of metastatic breast cancer. This treatment regimen was shown to significantly increase the extracellular pH, but not the intracellular pH, of tumors by 31P magnetic resonance spectroscopy and the export of acid from growing tumors by fluorescence microscopy of tumors grown in window chambers. NaHCO3 therapy also reduced the rate of lymph node involvement, yet did not affect the levels of circulating tumor cells, suggesting that reduced organ metastases were not due to increased intravasation. In contrast, NaHCO3 therapy significantly reduced the formation of hepatic metastases following intrasplenic injection, suggesting that it did inhibit extravasation and colonization. In tail vein injections of alternative cancer models, bicarbonate had mixed results, inhibiting the formation of metastases from PC3M prostate cancer cells, but not those of B16 melanoma. Although the mechanism of this therapy is not known with certainty, low pH was shown to increase the release of active cathepsin B, an important matrix remodeling protease. PMID:19276390

  15. Riparian buffers and potentially unstable ground

    NASA Astrophysics Data System (ADS)

    Tang, Swee May; Montgomery, David R.

    1995-09-01

    The spatial coincidence between riparian buffers of various widths and extents and potentially unstable ground was quantified using a physically based model for shallow landslide initiation and GIS for two watersheds on the Olympic Peninsula, Washington, USA. The proportion of the potentially unstable ground in each watershed within riparian buffers is a function of both buffer width and the extent of the stream channel network being buffered. While current buffers required by Washington State cover less than 5% of the potentially unstable ground, buffering all stream channels in these watersheds with 100-m buffers covered 75%-90% of the potentially unstable areas. Our analyses further show that: (1) riparian buffers are not efficient mechanisms for protecting potentially unstable ground, and (2) identifying potentially unstable ground using a physically based model should prove more effective for designing methods to reduce shallow landsliding hazards than relying on extensive buffer zones along stream channels.

  16. Partner Buffering of Attachment Insecurity

    PubMed Central

    Simpson, Jeffry A.; Overall, Nickola C.

    2014-01-01

    Insecurely attached people have less happy, unstable romantic relationships, but the quality of their relationships should depend on how their partners regulate them. Some partners find ways to buffer (emotionally and behaviorally regulate) insecurely attached individuals, which makes them feel better, behave more constructively, and improves their relationships. Understanding when and how this important interpersonal process works requires a dyad-centered approach. In this article, we describe core tenets of attachment theory and the two forms of attachment insecurity (anxiety and avoidance). We then present the Dyadic Regulation Model of Insecurity Buffering, which explains how and why certain types of buffering behaviors soothe the worries and improve the relationship perceptions and behaviors of anxious or avoidant people. We next review studies of couples trying to resolve major conflicts that illustrate some ways in which partners can successfully buffer the insecure reactions of anxious and avoidant individuals. We conclude by discussing other traits and social contexts to which our model can be applied. PMID:25214722

  17. Thermal decomposition of sodium bicarbonate and its effect on the reaction of sodium bicarbonate and sulfur dioxide in a simulated flue gas

    SciTech Connect

    Keener, T.C.

    1982-01-01

    The effect of thermally decomposing sodium bicarbonate while simultaneously reacting with SO/sub 2/, was studied. The study was performed by quantitatively determining the rate of thermal decomposition as a function of particle size in an SO/sub 2/ free gas stream. The rate of reaction of sodium carbonate (product of the thermal decomposition) with SO/sub 2/ was then studied, and the data applied to a pore-plugging model which accounts for the loss in reactivity with increased reaction time. The reaction of sodium bicarbonate with SO/sub 2/ was then studied and the results compared to that for sodium carbonate. From the analysis of the data, the activation energy for the thermal decomposition reaction, the SO/sub 2/ sodium carbonate and SO/sub 2/ sodium bicarbonate reaction were derived. The thermal decomposition reaction of sodium biocarbonate was found to be similar to that of calcium carbonate below the point where heat transfer is rate limiting. The degree of conversion of sodium bicarbonate was found to be 12-17 times greater (depending on particle size) than that of sodium carbonate in the temperature range 250/sup 0/-350/sup 0/F (120/sup 0/-177/sup 0/C). This greater conversion was qualitatively explained by hypothesizing the formation of an activated species during thermal decomposition which would be more chemically reactive.

  18. Crystallization characteristics of ammonium uranyl carbonate (AUC) in ammonium carbonate solutions

    NASA Astrophysics Data System (ADS)

    Tae-Joon, Kim; Kyung-Chai, Jeong; Jin-Ho, Park; In-Soon, Chang; Cheong-Song, Choi

    1994-05-01

    Ammonium carbonate solutions with an excessive amount of NH 3 were produced in a commercial AUC (ammonium uranyl carbonate) conversion plant. In this study the AUC crystals, precipitated with uranyl nitrate and ammonium carbonate solutions prepared in the laboratory, were characterized to determine the feasibility of recycling ammonium carbonate solution. The AUC crystals were easily agglomerated with the increasing concentration of CO 32- and mole ratio of {NH 4+}/{CO 32-} in ammonium carbonate solution. Effects of a mixing system for the solution in the AUC crystallizer and the feed location of the solution on the agglomeration of AUC crystals were also studied along with the effects of agglomerated AUC powders on UO 2 powders. Finally, the feasibility of manufacturing UO 2 fuel with a sintered pellet density of 10.52 g/cm 3, using the AUC powders generated in this experiment, was demonstrated.

  19. Calcium sulphate in ammonium sulphate solution

    USGS Publications Warehouse

    Sullivan, E.C.

    1905-01-01

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

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

    NASA Astrophysics Data System (ADS)

    Vallet, Valérie; Masella, Michel

    2015-01-01

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

  1. Cell buffer with built-in test

    NASA Technical Reports Server (NTRS)

    Ott, William E. (Inventor)

    2004-01-01

    A cell buffer with built-in testing mechanism is provided. The cell buffer provides the ability to measure voltage provided by a power cell. The testing mechanism provides the ability to test whether the cell buffer is functioning properly and thus providing an accurate voltage measurement. The testing mechanism includes a test signal-provider to provide a test signal to the cell buffer. During normal operation, the test signal is disabled and the cell buffer operates normally. During testing, the test signal is enabled and changes the output of the cell buffer in a defined way. The change in the cell buffer output can then be monitored to determine if the cell buffer is functioning correctly. Specifically, if the voltage output of the cell buffer changes in a way that corresponds to the provided test signal, then the functioning of the cell buffer is confirmed. If the voltage output of the cell buffer does not change correctly, then the cell buffer is known not to be operating correctly. Thus, the built in testing mechanism provides the ability to quickly and accurately determine if the cell buffer is operating correctly. Furthermore, the testing mechanism provides this functionality without requiring excessive device size and complexity.

  2. Acute sodium bicarbonate loading has negligible effects on resting and exercise blood pressure but causes gastrointestinal distress.

    PubMed

    Kahle, Laura E; Kelly, Patrick V; Eliot, Kathrin A; Weiss, Edward P

    2013-06-01

    Oral ingestion of sodium bicarbonate (bicarbonate loading) has acute ergogenic effects on short-duration, high-intensity exercise. Because sodium bicarbonate is 27% sodium, ergogenic doses (ie, 300 mg?kg?¹) result in sodium intakes well above the Dietary Reference Intakes upper limit of 2300 mg/day. Therefore, it is conceivable that bicarbonate loading could have hypertensive effects. Therefore, we performed a double-blind crossover trial to evaluate the hypothesis that bicarbonate loading increases resting and exercise blood pressure (BP). A secondary hypothesis was that bicarbonate loading causes gastrointestinal distress. Eleven endurance-trained men and women (exercise frequency, 4.6 ± 0.4 sessions/wk; duration, 65 ± 6 min/session) underwent testing on two occasions in random sequence: once after bicarbonate loading (300 mg?kg?¹) and once after placebo ingestion. BP and heart rate were measured before bicarbonate or placebo consumption, 30 minutes after consumption, during 20 min of steady state submaximal cycling exercise, and during recovery. Bicarbonate loading did not affect systolic BP during rest, exercise, or recovery (P = .38 for main treatment effect). However, it resulted in modestly higher diastolic BP (main treatment effect, +3.3 ± 1.1 mmHg, P = .01) and higher heart rate (main treatment effect, +10.1 ± 2.4 beats per minute, P = .002). Global ratings of gastrointestinal distress severity (0-10 scale) were greater after bicarbonate ingestion (5.1 ± 0.5 vs 0.5 ± 0.2, P < .0001). Furthermore, 10 of the 11 subjects (91%) experienced diarrhea, 64% experience bloating and thirst, and 45% experienced nausea after bicarbonate loading. In conclusion, although a single, ergogenic dose of sodium bicarbonate does not appear to have acute, clinically important effects on resting or exercise BP, it does cause substantial gastrointestinal distress. PMID:23746564

  3. Acute sodium bicarbonate loading has negligible effects on resting and exercise blood pressure but causes gastrointestinal distress

    PubMed Central

    Kahle, Laura E.; Kelly, Patrick V.; Eliot, Kathrin A.; Weiss, Edward P.

    2013-01-01

    Oral ingestion of sodium bicarbonate (bicarbonate loading) has acute ergogenic effects on short-duration, high-intensity exercise. Because sodium bicarbonate is 27% sodium, ergogenic doses (i.e. 300 mg·kg?1) result in sodium intakes well above the Dietary Reference Intakes upper limit of 2300 mg/day. Therefore, it is conceivable that bicarbonate loading could have hypertensive effects. Therefore, we performed a double-blind cross-over trial to evaluate the hypothesis that bicarbonate loading increases resting and exercise blood pressure (BP). A secondary hypothesis was that bicarbonate loading causes gastrointestinal distress. Eleven endurance-trained men and women (exercise frequency, 4.6±0.4 sessions/wk; duration, 65±6 min/session) underwent testing on two occasions in random sequence: once after bicarbonate loading (300 mg·kg?1) and once after placebo ingestion. BP and heart rate (HR) were measured before bicarbonate or placebo consumption, 30 minutes after consumption, during 20 min of steady state submaximal cycling exercise, and during recovery. Bicarbonate loading did not affect systolic BP during rest, exercise, or recovery (p=0.38 for main treatment effect). However, it resulted in modestly higher diastolic BP (main treatment effect, +3.3±1.1 mmHg, p=0.01) and higher HR (main treatment effect, +10.1±2.4 bpm, p=0.002). Global ratings of gastrointestinal distress severity (0–10 scale) were greater after bicarbonate ingestion (5.1±0.5 vs. 0.5±0.2, p<0.0001). Furthermore, 10 of the 11 subjects (91%) experienced diarrhea, 64% experience bloating and thirst, and 45% experienced nausea after bicarbonate loading. In conclusion, although a single, ergogenic dose of sodium bicarbonate does not appear to have acute, clinically important effects on resting or exercise BP, it does cause substantial GI distress. PMID:23746564

  4. Stacked Switched Capacitor Energy Buffer Architecture

    E-print Network

    Chen, Minjie

    Electrolytic capacitors are often used for energy buffering applications, including buffering between single-phase ac and dc. While these capacitors have high energy density compared to film and ceramic capacitors, their ...

  5. Stacked switched capacitor energy buffer architecture

    E-print Network

    Chen, Minjie, S.M. Massachusetts Institute of Technology

    2012-01-01

    Electrolytic capacitors are often used for energy buffering applications, including buffering between single-phase ac and dc. While these capacitors have high energy density compared to film and ceramic capacitors, their ...

  6. Eutectic composite explosives containing ammonium nitrate

    SciTech Connect

    Stinecipher, M.M.

    1981-01-01

    The eutectic of ammonium nitrate (AN), the ammonium salt of 3,5-dinitro-1,2,4-triazole was prepared and its sensitivity and performance were studied. It was found that this AN formulation was unusual in that it performed ideally at small diameter, which indicated that it was a monomolecular explosive. Sensitivity tests included type 12 impact, Henkin thermal and wedge tests, and performance tests included rate stick/plate dent, cylinder, and aquarium tests. Results were compared with calculations, standard explosives, and another eutectic, ethylendiamine dinitrate (EDD)/AN.

  7. Supercritical water oxidation of ammonium picrate

    SciTech Connect

    LaJeunesse, C.A.; Mills, B.E.; Brown, B.G.

    1994-11-01

    This study demonstrates the feasibility of using supercritical water oxidation to destroy ammonium picrate. Analyses of reactor effluent composition at various temperatures, residence times, and oxidant concentrations were used to design an improved reactor configuration for achieving destruction with minimum corrosion. The engineering evaluation reactor, a room-sized laboratory scale reactor, was reconfigured to incorporate this design change. Destruction of ammonium picrate with minimized corrosion was demonstrated on this reconfigured reactor. Factors that must be considered in scaling up to pilot plant size are discussed.

  8. On the evaporation of ammonium sulfate solution

    PubMed Central

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

    2009-01-01

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

  9. On the evaporation of ammonium sulfate solution

    SciTech Connect

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

    2009-07-16

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

  10. Brain metabolism and intracellular pH during ischaemia: effects of systemic glucose and bicarbonate administration studied by 31P and 1H nuclear magnetic resonance spectroscopy in vivo in the lamb.

    PubMed

    Hope, P L; Cady, E B; Delpy, D T; Ives, N K; Gardiner, R M; Reynolds, E O

    1988-05-01

    Brain metabolism and intracellular pH were studied during and after episodes of incomplete cerebral ischaemia in lambs under sodium pentobarbitone anaesthesia. 31P and 1H magnetic resonance spectroscopy was used to monitor brain pHi and brain concentrations of inorganic phosphate (Pi), phosphocreatine (PCr), beta-nucleoside triphosphate (beta NTP), and lactate. Simultaneous measurements were made of arterio-cerebral venous concentration differences (AVDs) for oxygen, glucose, and lactate. Cerebral ischaemia was induced by a combination of bilateral carotid clamping and hypotension, and the acute effects of systemic administration of glucose and sodium bicarbonate were examined. The molar ratio of glucose to oxygen uptake by the brain (6G/O2) increased above unity during cerebral ischaemia. Statistically significant AVDs for lactate were not observed. Cerebral ischaemia was associated with a reduction in brain pHi PCr/Pi ratio, and an increase in brain lactate. No effect of arterial plasma glucose on brain lactate concentration or brain pHi was evident during cerebral ischaemia or in the postischaemic period. Administration of sodium bicarbonate systemically in the postischaemic period was associated with a rise in arterial and brain tissue PCO2. A fall in brain pHi occurred which was attributable in part to coincidental brain lactate accumulation. The increase in brain lactate measured by 1H nuclear magnetic resonance in vivo during ischaemia was insufficient to account for the change in buffer base calculated to have occurred from previous estimates of brain buffering capacity. PMID:2834511

  11. Radiolysis of Bicarbonate and Carbonate Aqueous Solutions: Product Analysis and Simulation of Radiolytic Processes

    SciTech Connect

    Cai Zhongli; Li Xifeng; Katsumura, Yosuke; Urabe, Osamu [University of Tokyo (Japan)

    2001-11-15

    An understanding of the radiation-induced effects in groundwater is essential to evaluate the safe geological disposal of spent fuel. In groundwater, the bicarbonate ion is the predominant and common anion; this work investigated radiation-induced chemical reactions of (bi)carbonate aqueous solutions with steady-state irradiation and pulse radiolysis methods. Aqueous solutions of sodium (bi)carbonate as high as 50 mmol.dm{sup -3} were used. The formation of formate, oxalate, and H{sub 2}O{sub 2} were measured under different conditions. A complete set of reaction steps and reliable kinetic data for the radiolysis of (bi)carbonate aqueous solutions at ionic strength close to the groundwater were proposed. Kinetic calculations were completed based on the proposed reaction steps and the kinetic data obtained in the present work. The results from the calculation are in good agreement with the experimental results. With these proposed reaction steps and kinetic data, computer simulation can be performed to predict the yield of radiolytic products of (bi)carbonate aqueous solutions as a function of irradiation time and used to evaluate the safety of geological disposal options of spent fuel.

  12. Effect of cimetidine and sodium bicarbonate on pancreatic replacement therapy in cystic fibrosis.

    PubMed Central

    Durie, P R; Bell, L; Linton, W; Corey, M L; Forstner, G G

    1980-01-01

    Fifteen patients with cystic fibrosis and pancreatic insufficiency were studied during four randomised seven day treatment periods in which they received only pancreatic supplement (Pancrelipase, 27 capsules per day) or supplement plus cimetidine (20 mg/kg body weight/24 h) or sodium bicarbonate (15 g/m2/24 h) alone or in combination. Dietary intake was not fixed but was restricted to foods of known fat and nitrogen content from which daily intakes could be computed. Faecal fat and nitrogen were calculated as g/24 h and percentage of intake. Addition of either cimetidine or bicarbonate resulted in significant improvement in fat and nitrogen excretion, which was not greater with the combination of both drugs. Cimetidine and sodium bicarbonate in these doses are therefore sufficient to produce maximal improvement in digestive activity of pancreatic supplements. Fat excretion per gram of intake fell with cimetidine and bicarbonate from 12 times the normal level, to normal, in patients consuming less than 120 g fat daily. Above this intake the dose of pancreatic supplement appeared to be inadequate. Faecal nitrogen excretion increased with nitrogen intake in all four periods, but, in contrast with fat excretion, the response to cimetidine and bicarbonate was not affected by the level of intake. Dietary intake appears to be a significant factor in determining the faecal output of fat and nitrogen in patients with pancreatic insufficiency and should be considered when determining the optimum amount of pancreatic supplementation. PMID:7429342

  13. Laser velocimeter (autocovariance) buffer interface

    NASA Technical Reports Server (NTRS)

    Clemmons, J. I., Jr.

    1981-01-01

    A laser velocimeter (autocovariance) buffer interface (LVABI) was developed to serve as the interface between three laser velocimeter high speed burst counters and a minicomputer. A functional description is presented of the instrument and its unique features which allow the studies of flow velocity vector analysis, turbulence power spectra, and conditional sampling of other phenomena. Typical applications of the laser velocimeter using the LVABI are presented to illustrate its various capabilities.

  14. Doped LZO buffer layers for laminated conductors

    DOEpatents

    Paranthaman, Mariappan Parans (Knoxville, TN) [Knoxville, TN; Schoop, Urs (Westborough, MA) [Westborough, MA; Goyal, Amit (Knoxville, TN) [Knoxville, TN; Thieme, Cornelis Leo Hans (Westborough, MA) [Westborough, MA; Verebelyi, Darren T. (Oxford, MA) [Oxford, MA; Rupich, Martin W. (Framingham, MA) [Framingham, MA

    2010-03-23

    A laminated conductor includes a metallic substrate having a surface, a biaxially textured buffer layer supported by the surface of the substrate, the biaxially textured buffer layer comprising LZO and a dopant for mitigating metal diffusion through the LZO, and a biaxially textured conductor layer supported by the biaxially textured buffer layer.

  15. Power-state-aware buffered tree construction

    Microsoft Academic Search

    Iris Hui-ru Jiang; Ming-hua Wu

    2008-01-01

    Interconnect delay and low power are two of the main issues in nano technology. Buffer insertion during routing effectively reduces interconnect delay; power state management and multiple supply voltage significantly lower power consumption. However, buffering without considering power states in multiple supply voltage designs may cause the signal integrity problem. This paper first considers power states into buffered tree construction.

  16. Riparian buffers and potentially unstable ground

    Microsoft Academic Search

    Swee May Tang; David R. Montgomery

    1995-01-01

    The spatial coincidence between riparian buffers of various widths and extents and potentially unstable ground was quantified using a physically based model for shallow landslide initiation and GIS for two watersheds on the Olympic Peninsula, Washington, USA. The proportion of the potentially unstable ground in each watershed within riparian buffers is a function of both buffer width and the extent

  17. An electric fence for kernel buffers

    Microsoft Academic Search

    Nikolai Joukov; Aditya Kashyap; Gopalan Sivathanu; Erez Zadok

    2005-01-01

    Improper access of data buffers is one of the most common errors in programs written in assembler, C, C++, and several other languages. Existing programs and OSs frequently access the data beyond the allocated buffers or access buffers that were already freed. Such programs and OSs may run for years before their problems can be detected because improper memory accesses

  18. Understanding the Science Behind Riparian Forest Buffers

    E-print Network

    Liskiewicz, Maciej

    , and eco- logical functions and important social benefits. #12;1 Introduction Forested riparian buffersUnderstanding the Science Behind Riparian Forest Buffers: Factors Influencing Adoption #12;*Faculty Cheatham Hall, Blacksburg, VA 24061 Understanding the Science Behind Riparian Forest Buffers: Factors

  19. 40 CFR 418.60 - Applicability; description of the ammonium sulfate production subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Applicability; description of the ammonium sulfate production subcategory. 418...MANUFACTURING POINT SOURCE CATEGORY Ammonium Sulfate Production Subcategory § 418...Applicability; description of the ammonium sulfate production subcategory....

  20. 40 CFR 418.60 - Applicability; description of the ammonium sulfate production subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...Applicability; description of the ammonium sulfate production subcategory. 418...MANUFACTURING POINT SOURCE CATEGORY Ammonium Sulfate Production Subcategory § 418...Applicability; description of the ammonium sulfate production subcategory....

  1. 40 CFR 721.10170 - Polyoxyethylene polyalkylarylphenylether sulfate ammonium salt (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Polyoxyethylene polyalkylarylphenylether sulfate ammonium salt (generic). 721.10170...Polyoxyethylene polyalkylarylphenylether sulfate ammonium salt (generic). (a...polyoxyethylene polyalkylarylphenylether sulfate ammonium salt (PMN...

  2. 40 CFR 418.60 - Applicability; description of the ammonium sulfate production subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...Applicability; description of the ammonium sulfate production subcategory. 418...MANUFACTURING POINT SOURCE CATEGORY Ammonium Sulfate Production Subcategory § 418...Applicability; description of the ammonium sulfate production subcategory....

  3. 40 CFR 721.10170 - Polyoxyethylene polyalkylarylphenylether sulfate ammonium salt (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Polyoxyethylene polyalkylarylphenylether sulfate ammonium salt (generic). 721.10170...Polyoxyethylene polyalkylarylphenylether sulfate ammonium salt (generic). (a...polyoxyethylene polyalkylarylphenylether sulfate ammonium salt (PMN...

  4. 40 CFR 418.60 - Applicability; description of the ammonium sulfate production subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...Applicability; description of the ammonium sulfate production subcategory. 418...MANUFACTURING POINT SOURCE CATEGORY Ammonium Sulfate Production Subcategory § 418...Applicability; description of the ammonium sulfate production subcategory....

  5. 40 CFR 418.60 - Applicability; description of the ammonium sulfate production subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Applicability; description of the ammonium sulfate production subcategory. 418...MANUFACTURING POINT SOURCE CATEGORY Ammonium Sulfate Production Subcategory § 418...Applicability; description of the ammonium sulfate production subcategory....

  6. 21 CFR 180.37 - Saccharin, ammonium saccharin, calcium saccharin, and sodium saccharin.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...true Saccharin, ammonium saccharin, calcium saccharin, and sodium saccharin. 180...37 Saccharin, ammonium saccharin, calcium saccharin, and sodium saccharin. ...additives saccharin, ammonium saccharin, calcium saccharin, and sodium...

  7. Migration behaviour of discontinuous buffers in capillary electrophoresis during protein enrichment.

    PubMed

    Li, Ting; Booker, Christina J; Yeung, Ken K-C

    2012-10-21

    Capillary electrophoresis (CE) is not only an effective separation technique, but can also serve as a sample preparation tool for enrichment and purification at sub-microliter sample volumes. Our approach is based on the use of a discontinuous buffer system consisting of an acid and a base (acetate and ammonium). Proteins and/or peptides with isoelectric points between the pH values of these two buffers will become stacked at the neutralization reaction boundary (NRB). To understand the mechanism of the NRB formation and the electrophoretic migration of various ions during the enrichment, we performed experiments using myoglobin and mesityl oxide to reveal the ion migration patterns at the buffer junction, and utilized Simul 5 to computer simulate the process. The simulated results closely resembled the experimental data, and together, they effectively revealed the characteristics of the discontinuous buffers. Importantly, the discovery allowed the manipulation of NRB behaviours by controlling the discontinuous buffer composition. To illustrate this, the removal of urea as an unwanted background molecule from the enriched protein sample was achieved based on the acquired information. PMID:22919699

  8. Enhanced H+ Diffusion by NH4+\\/HCO3-: Implications for Helicobacter-pylori-Associated Peptic Ulceration

    Microsoft Academic Search

    M. A. Desai; P. M. Vadgama

    1993-01-01

    The in vitro effect of ammonium bicarbonate buffer on mucus H+ permeability is reported here. The diffusional resistance of mucus and water was demonstrated to be dependent on buffer concentration, and the contrast between the two types of layers was most pronounced for low buffer concentration near neutrality. Moreover, the pKa values of HCO3- and NH3 had a profound effect

  9. Effects of Cathodic Potential, Bicarbonate, and Chloride Ions on SCC of X70 Pipeline Steel

    NASA Astrophysics Data System (ADS)

    Shahriari, A.; Shahrabi, T.; Oskuie, A. A.

    2013-05-01

    This is an investigation on the stress corrosion cracking (SCC) behavior of X70 pipeline steel in high pH carbonate-bicarbonate solutions with different concentrations of bicarbonate and chloride ions and at cathodic potential of -1100 mV versus saturated calomel electrode (SCE) using slow strain rate testing. Electrochemical techniques such as potentiodynamic polarization and electrochemical impedance spectroscopy were used to investigate the electrochemical behavior of X70 pipeline steel in solutions with different concentrations. X70 pipeline steel fracture surface morphology in these different solutions was also studied by scanning electron microscopy (SEM). The results suggested that the susceptibility to SCC for X70 pipeline steel decreased in the most dilute carbonate-bicarbonate solution in the absence of the chloride ion. Also, at potential of -1100 mV versus SCE, all fracture surfaces showed semi-brittle behavior with transgranular cracks.

  10. Comparative shell buffering properties correlate with anoxia tolerance in freshwater turtles.

    PubMed

    Jackson, Donald C; Taylor, Sarah E; Asare, Vivian S; Villarnovo, Dania; Gall, Jonathan M; Reese, Scott A

    2007-02-01

    Freshwater turtles as a group are more resistant to anoxia than other vertebrates, but some species, such as painted turtles, for reasons not fully understood, can remain anoxic at winter temperatures far longer than others. Because buffering of lactic acid by the shell of the painted turtle is crucial to its long-term anoxic survival, we have tested the hypothesis that previously described differences in anoxia tolerance of five species of North American freshwater turtles may be explained at least in part by differences in their shell composition and buffering capacity. All species tested have large mineralized shells. Shell comparisons included 1) total shell CO2 concentration, 2) volume of titrated acid required to hold incubating shell powder at pH 7.0 for 3 h (an indication of buffer release from shell), and 3) lactate concentration of shell samples incubated to equilibrium in a standard lactate solution. For each measurement, the more anoxia-tolerant species (painted turtle, Chrysemys picta; snapping turtle, Chelydra serpentina) had higher values than the less anoxia-tolerant species (musk turtle, Sternotherus odoratus; map turtle, Graptemys geographica; red-eared slider, Trachemys scripta). We suggest that greater concentrations of accessible CO2 (as carbonate or bicarbonate) in the more tolerant species enable these species, when acidotic, to release more buffer into the extracellular fluid and to take up more lactic acid into their shells. We conclude that the interspecific differences in shell composition and buffering can contribute to, but cannot explain fully, the variations observed in anoxia tolerance among freshwater turtles. PMID:17008457

  11. MECHANISM BY WHICH AMMONIUM FERTILIZERS KILL LARKSPUR

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  12. Diamond Head Revisited with Ammonium Dichromate.

    ERIC Educational Resources Information Center

    Arrigoni, Edward

    1981-01-01

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

  13. Tunicate Eggs Utilize Ammonium Ions for Flotation

    Microsoft Academic Search

    Charles C. Lambert; Gretchen Lambert

    1978-01-01

    Unlike most solitary ascidians, Corella willmeriana retains its eggs and embryos well past hatching. The early stages float to the top of the enlarged atrium from which they cannot escape. Ammonium ions replace other more dense substances in the cell sap of the float cells surrounding the embryo. Energy derived from glycolysis but not mitochondrial processes supports this process.

  14. Review on Thermal Decomposition of Ammonium Nitrate

    Microsoft Academic Search

    Shalini Chaturvedi; Pragnesh N. Dave

    2013-01-01

    In this review data from the literature on thermal decomposition of ammonium nitrate (AN) and the effect of additives to their thermal decomposition are summarized. The effect of additives like oxides, cations, inorganic acids, organic compounds, phase-stablized CuO, etc., is discussed. The effect of an additive mainly occurs at the exothermic peak of pure AN in a temperature range of

  15. Ammonium nitrate: a promising rocket propellant oxidizer

    Microsoft Academic Search

    C. Oommen; S. R. Jain

    1999-01-01

    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

  16. 21 CFR 73.1298 - Ferric ammonium ferrocyanide.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...resulting from mixing solutions of ferrous sulfate and sodium ferrocyanide in the presence of ammonium sulfate. The oxidized product is filtered, washed...pigment consists principally of ferric ammonium ferrocyanide with smaller amounts of...

  17. 21 CFR 73.1298 - Ferric ammonium ferrocyanide.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...resulting from mixing solutions of ferrous sulfate and sodium ferrocyanide in the presence of ammonium sulfate. The oxidized product is filtered, washed...pigment consists principally of ferric ammonium ferrocyanide with smaller amounts of...

  18. 21 CFR 73.1298 - Ferric ammonium ferrocyanide.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...resulting from mixing solutions of ferrous sulfate and sodium ferrocyanide in the presence of ammonium sulfate. The oxidized product is filtered, washed...pigment consists principally of ferric ammonium ferrocyanide with smaller amounts of...

  19. 21 CFR 73.1298 - Ferric ammonium ferrocyanide.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...resulting from mixing solutions of ferrous sulfate and sodium ferrocyanide in the presence of ammonium sulfate. The oxidized product is filtered, washed...pigment consists principally of ferric ammonium ferrocyanide with smaller amounts of...

  20. 21 CFR 73.1298 - Ferric ammonium ferrocyanide.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...resulting from mixing solutions of ferrous sulfate and sodium ferrocyanide in the presence of ammonium sulfate. The oxidized product is filtered, washed...pigment consists principally of ferric ammonium ferrocyanide with smaller amounts of...

  1. 40 CFR 180.473 - Glufosinate ammonium; tolerances for residues.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...glufosinate ammonium, 2-amino-4-(hydroxymethylphosphinyl)butanoic acid monoammonium salt...equivalent of 2-amino-4-(hydroxymethylphosphinyl)butanoic acid, in or on the commodity...glufosinate ammonium, 2-amino-4-(hydroxymethylphosphinyl)butanoic acid monoammonium...

  2. 40 CFR 180.473 - Glufosinate ammonium; tolerances for residues.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...glufosinate ammonium, 2-amino-4-(hydroxymethylphosphinyl)butanoic acid monoammonium salt...equivalent of 2-amino-4-(hydroxymethylphosphinyl)butanoic acid, in or on the commodity...glufosinate ammonium, 2-amino-4-(hydroxymethylphosphinyl)butanoic acid monoammonium...

  3. Buffered Communication Analysis in Distributed Multiparty Sessions

    NASA Astrophysics Data System (ADS)

    Deniélou, Pierre-Malo; Yoshida, Nobuko

    Many communication-centred systems today rely on asynchronous messaging among distributed peers to make efficient use of parallel execution and resource access. With such asynchrony, the communication buffers can happen to grow inconsiderately over time. This paper proposes a static verification methodology based on multiparty session types which can efficiently compute the upper bounds on buffer sizes. Our analysis relies on a uniform causality audit of the entire collaboration pattern - an examination that is not always possible from each end-point type. We extend this method to design algorithms that allocate communication channels in order to optimise the memory requirements of session executions. From these analyses, we propose two refinements methods which respect buffer bounds: a global protocol refinement that automatically inserts confirmation messages to guarantee stipulated buffer sizes and a local protocol refinement to optimise asynchronous messaging without buffer overflow. Finally our work is applied to overcome a buffer overflow problem of the multi-buffering algorithm.

  4. High temperature attack of ores by means of a liquor essentially containing a soluble bicarbonate

    SciTech Connect

    Bosca, B.; Maurel, P.; Nicolas, F.

    1981-10-20

    A process for the oxidizing attack at high temperature of ores containing at least one metal belonging to the group formed by uranium, vanadium and molybdenum, by means of an aqueous liquor containing a majority of sodium bicarbonate and a minority of sodium carbonate according to a ratio by weight of sodium bicarbonate to sodium carbonate of at least 1.5, in the presence of free oxygen injected into the reaction medium, this medium being maintained at a temperature of between 160/sup 0/C and 300/sup 0/C. For at most six hours.

  5. The effects of combined glucose-electrolyte and sodium bicarbonate ingestion on prolonged intermittent exercise performance

    Microsoft Academic Search

    Mike James Price; David Cripps

    2012-01-01

    This study examined the effects of combined glucose and sodium bicarbonate ingestion prior to intermittent exercise. Ninemales (mean ± s age 25.4 ± 6.6 years, body mass 78.8 ± 12.0 kg, maximal oxygen uptake ([Vdot]O2max) 47.0 ± 7ml · kg · min) undertook 4 × 45 min intermittent cycling trials including 15 × 10 s sprints one hour after ingesting placebo (PLA), glucose (CHO), sodium bicarbonate (NaHCO3) or a combined CHO and NaHCO3 solution (COMB). Post ingestion

  6. Ammonium tris­(tetra­ethyl­ammonium) hexa­cosa­oxidoocta­molybdate

    PubMed Central

    Zebiri, Ikram; Bencharif, Leïla; Direm, Amani; Bencharif, Mustapha; Benali-Cherif, Nourredine

    2008-01-01

    The structure of the title compound, NH4(C8H20N)3[Mo8O26], is built up by discrete cations and anions, with two formula units in the asymmetric unit. The ?-octa­molybdate anions are linked to the ammonium cations via N—H?O hydrogen bonding involving terminal oxide groups and to the tetra­ethyl­ammonium cations via weak C—H?O inter­actions. PMID:21201863

  7. Transcriptional Responses of a Bicarbonate-Tolerant Monocot, Puccinellia tenuiflora, and a Related Bicarbonate-Sensitive Species, Poa annua, to NaHCO3 Stress

    PubMed Central

    Kobayashi, Shio; Satone, Hina; Tan, Engkong; Kurokochi, Hiroyuki; Asakawa, Shuichi; Liu, Shenkui; Takano, Tetsuo

    2014-01-01

    Puccinellia tenuiflora is an alkaline salt-tolerant monocot found in saline-alkali soil in China. To identify the genes which are determining the higher tolerance of P. tenuiflora compared to bicarbonate sensitive species, we examined the responses of P. tenuiflora and a related bicarbonate-sensitive Poeae plant, Poa annua, to two days of 20 mM NaHCO3 stress by RNA-seq analysis. We obtained 28 and 38 million reads for P. tenuiflora and P. annua, respectively. For each species, the reads of both unstressed and stressed samples were combined for de novo assembly of contigs. We obtained 77,329 contigs for P. tenuiflora and 115,335 contigs for P. annua. NaHCO3 stress resulted in greater than two-fold absolute expression value changes in 157 of the P. tenuiflora contigs and 1090 of P. annua contigs. Homologs of the genes involved in Fe acquisition, which are important for the survival of plants under alkaline stress, were up-regulated in P. tenuiflora and down-regulated in P. annua. The smaller number of the genes differentially regulated in P. tenuiflora suggests that the genes regulating bicarbonate tolerance are constitutively expressed in P. tenuiflora. PMID:25551599

  8. Transcriptional responses of a bicarbonate-tolerant monocot, Puccinellia tenuiflora, and a related bicarbonate-sensitive species, Poa annua, to NaHCO3 stress.

    PubMed

    Kobayashi, Shio; Satone, Hina; Tan, Engkong; Kurokochi, Hiroyuki; Asakawa, Shuichi; Liu, Shenkui; Takano, Tetsuo

    2015-01-01

    Puccinellia tenuiflora is an alkaline salt-tolerant monocot found in saline-alkali soil in China. To identify the genes which are determining the higher tolerance of P. tenuiflora compared to bicarbonate sensitive species, we examined the responses of P. tenuiflora and a related bicarbonate-sensitive Poeae plant, Poa annua, to two days of 20 mM NaHCO3 stress by RNA-seq analysis. We obtained 28 and 38 million reads for P. tenuiflora and P. annua, respectively. For each species, the reads of both unstressed and stressed samples were combined for de novo assembly of contigs. We obtained 77,329 contigs for P. tenuiflora and 115,335 contigs for P. annua. NaHCO3 stress resulted in greater than two-fold absolute expression value changes in 157 of the P. tenuiflora contigs and 1090 of P. annua contigs. Homologs of the genes involved in Fe acquisition, which are important for the survival of plants under alkaline stress, were up-regulated in P. tenuiflora and down-regulated in P. annua. The smaller number of the genes differentially regulated in P. tenuiflora suggests that the genes regulating bicarbonate tolerance are constitutively expressed in P. tenuiflora. PMID:25551599

  9. Pancreatic, hepatic, and duodenal mucosal bicarbonate secretion during infusion of secretin and cholecystokinin. Evidence of the importance of hepatic bicarbonate in the neutralization of acid in the duodenum of anaesthetized pigs.

    PubMed

    Ainsworth, M A; Ladegaard, L; Svendsen, P; Cantor, P; Olsen, O; Schaffalitzky de Muckadell, O B

    1991-10-01

    The effect of infusion of secretin alone or in combination with cholecystokinin (CCK) on pancreatic, hepatic, and duodenal mucosal bicarbonate secretion was studied in anaesthetized pigs. After laparotomy, catheters were inserted into the common bile duct, the pancreatic duct, and both ends of the duodenum. Pancreatic, hepatic, and duodenal mucosal secretions were collected during intraportal infusion of increasing doses of secretin, either alone or in combination with CCK. During infusion of secretin in doses that caused physiologic increases in plasma secretin concentrations the liver produced significantly more bicarbonate than the pancreas. A physiologic dose of CCK augmented the effect of secretin on both hepatic and pancreatic bicarbonate secretion, but the hepatic production of bicarbonate was still larger than the pancreatic production. Neither secretin alone nor secretin combined with CCK caused any changes in duodenal mucosal bicarbonate secretion. These results suggest that the liver plays an important role in the neutralization of acid in the duodenum. PMID:1947769

  10. Ammonium inactivation of nitrate reductase in Lemna minor L

    Microsoft Academic Search

    T. O. Orebamjo; G. R. Stewart

    1975-01-01

    The addition of ammonium to nitrate induced plants of Lemna minor L. brings about a rapid loss in extractable nitrate reductase activity. This inactivation is reversible both in vivo and in vitro. Inhibitors of RNA and protein synthesis do not protect nitrate reductase against ammonium inactivation. It is suggested that factors, in addition to ammonium ions, are components of the

  11. 21 CFR 573.560 - Iron ammonium citrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...Drugs 6 2011-04-01 2011-04-01 false Iron ammonium citrate. 573.560 Section 573.560...OF ANIMALS Food Additive Listing § 573.560 Iron ammonium citrate. Iron ammonium citrate may be safely used in animal...

  12. 21 CFR 573.560 - Iron ammonium citrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...Drugs 6 2012-04-01 2012-04-01 false Iron ammonium citrate. 573.560 Section 573.560...OF ANIMALS Food Additive Listing § 573.560 Iron ammonium citrate. Iron ammonium citrate may be safely used in animal...

  13. 21 CFR 172.430 - Iron ammonium citrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...Drugs 3 2013-04-01 2013-04-01 false Iron ammonium citrate. 172.430 Section 172.430...HUMAN CONSUMPTION Anticaking Agents § 172.430 Iron ammonium citrate. Iron ammonium citrate may be safely used in food in...

  14. 21 CFR 573.560 - Iron ammonium citrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...Drugs 6 2014-04-01 2014-04-01 false Iron ammonium citrate. 573.560 Section 573.560...OF ANIMALS Food Additive Listing § 573.560 Iron ammonium citrate. Iron ammonium citrate may be safely used in animal...

  15. 21 CFR 172.430 - Iron ammonium citrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...Drugs 3 2014-04-01 2014-04-01 false Iron ammonium citrate. 172.430 Section 172.430...HUMAN CONSUMPTION Anticaking Agents § 172.430 Iron ammonium citrate. Iron ammonium citrate may be safely used in food in...

  16. 21 CFR 172.430 - Iron ammonium citrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...Drugs 3 2012-04-01 2012-04-01 false Iron ammonium citrate. 172.430 Section 172.430...HUMAN CONSUMPTION Anticaking Agents § 172.430 Iron ammonium citrate. Iron ammonium citrate may be safely used in food in...

  17. 21 CFR 172.430 - Iron ammonium citrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...Drugs 3 2011-04-01 2011-04-01 false Iron ammonium citrate. 172.430 Section 172.430...HUMAN CONSUMPTION Anticaking Agents § 172.430 Iron ammonium citrate. Iron ammonium citrate may be safely used in food in...

  18. 21 CFR 573.560 - Iron ammonium citrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...Drugs 6 2013-04-01 2013-04-01 false Iron ammonium citrate. 573.560 Section 573.560...OF ANIMALS Food Additive Listing § 573.560 Iron ammonium citrate. Iron ammonium citrate may be safely used in animal...

  19. 40 CFR 721.6070 - Alkyl phosphonate ammonium salts.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false Alkyl phosphonate ammonium salts. 721.6070 Section 721.6070 ...721.6070 Alkyl phosphonate ammonium salts. (a) Chemical substances and significant...generically as alkyl phosphonate ammonium salts (PMNs P-93-725 and...

  20. 40 CFR 721.6070 - Alkyl phosphonate ammonium salts.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 false Alkyl phosphonate ammonium salts. 721.6070 Section 721.6070 ...721.6070 Alkyl phosphonate ammonium salts. (a) Chemical substances and significant...generically as alkyl phosphonate ammonium salts (PMNs P-93-725 and...

  1. 40 CFR 721.10430 - Tetra alkyl ammonium salt (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false Tetra alkyl ammonium salt (generic). 721.10430 Section 721... § 721.10430 Tetra alkyl ammonium salt (generic). (a) Chemical substance...identified generically as tetra alkyl ammonium salt (PMN P-97-823) is subject to...

  2. 21 CFR 573.560 - Iron ammonium citrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...Drugs 6 2010-04-01 2010-04-01 false Iron ammonium citrate. 573.560 Section 573.560...OF ANIMALS Food Additive Listing § 573.560 Iron ammonium citrate. Iron ammonium citrate may be safely used in animal...

  3. 21 CFR 172.430 - Iron ammonium citrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...Drugs 3 2010-04-01 2009-04-01 true Iron ammonium citrate. 172.430 Section 172.430...HUMAN CONSUMPTION Anticaking Agents § 172.430 Iron ammonium citrate. Iron ammonium citrate may be safely used in food in...

  4. STUDIES ON THE EFFECT OF AMMONIUM SULFATE ON CARCINOGENESIS

    EPA Science Inventory

    The project was designed to evaluate the health effects of ammonium sulfate (Nh4)2 SO4 inhalation using experimental animals. The questions studied were: (1) Is inhaled ammonium sulfate co-carcinogenic. (2) What are the deposition and clearance patterns of inhaled ammonium sulfat...

  5. Effect of ammonium ion distribution on Nafion ® conductivity

    Microsoft Academic Search

    Kitiya Hongsirikarn; Thirapong Napapruekchart; Xunhua Mo; James G. Goodwin Jr.

    2011-01-01

    Nafion® conductivity in a proton exchange membrane fuel cell (PEMFC) with the fuel stream containing ammonia is mainly affected by the ammonium ion composition and operating conditions. In this study, the effect of ammonium ion distribution on Nafion conductivity was investigated for the first time. The conductivities of two kinds of contaminated membranes having uniform and non-uniform ammonium ion distributions

  6. Control of Citrus Green Mold by Carbonate and Bicarbonate Salts and the Influence of Commercial Postharvest Practices on Their Efficacy

    Microsoft Academic Search

    Joseph L. Smilanick; Dennis A. Margosan; Franka Mlikota; Josep Usall; Ibrahim F. Michael

    1999-01-01

    Smilanick, J. L., Margosan, D. A., Mlikota, F., Usall, J., and Michael, I. F. 1999. Control of citrus green mold by carbonate and bicarbonate salts and the influence of commercial posthar- vest practices on their efficacy. Plant Dis. 83: 139-145. The toxicity to Penicillium digitatum and practical use of carbonate and bicarbonate salts to control green mold were determined. The

  7. Variation of Urinary pH and Bicarbonate Concentrations of Students in Metropolitan and Rural Areas of Japan

    Microsoft Academic Search

    Akio Tomoda; Shigeto Yamanaka; Hidehiko Kawai; Hiroshi Itoh; Maso Katsumata; Masayasu Minami; Takuma Hashimoto; Hideji Tanii; Kazuo Hashimoto

    1995-01-01

    Changes in urinary pH and bicarbonate levels were studied in urine collected before and after final examinations taken by 91 medical students (65 males, 26 females) in Tokyo and from 87 students (73 males, 14 females) in Kanazawa, a rural municipality. Bicarbonate levels and pH in the urine of students in both cities increased significantly after attending 2 h of

  8. Combined Effect of Bicarbonate and Insulin with Glucose in Acute Therapy of Hyperkalemia in End-Stage Renal Disease Patients

    Microsoft Academic Search

    Ho-Jung Kim

    1996-01-01

    This study was performed to evaluate the efficacy of various treatment modalities for hyperkalemia in 8 end-stage renal disease (ESRD) patients. Simultaneous administration of sodium bicarbonate and insulin with glucose was compared with infusion of either bicarbonate alone or insulin and glucose. Plasma potassium was measured at the baseline and after 60 min of infusion with each regimen. Infusion of

  9. Detection and Quantification of Bacteria Involved in Aerobic and Anaerobic Ammonium Oxidation in an Ammonium-Contaminated Aquifer

    Microsoft Academic Search

    Theo H. M. Smits; Arne Hüttmann; David N. Lerner; Christof Holliger

    2009-01-01

    The aerobic and anaerobic ammonium-oxidizing bacterial guilds were studied from two multilevel samplers in an ammonium-contaminated aquifer in the UK. By end point polymerase chain reaction (PCR), the presence of betaproteobacterial ammonium-oxidizing bacteria and anaerobic ammonium-oxidizing (anammox) planctomycetes was demonstrated. The sequences of cloned anammox-specific PCR fragments had close relationships with known anammox strains. Real-time PCR was subsequently used to

  10. Freezability of rat epididymal sperm induced by raffinose in modified Krebs-Ringer bicarbonate (mKRB) based extender solution.

    PubMed

    Yamashiro, Hideaki; Han, Young-Joon; Sugawara, Atsushi; Tomioka, Ikuo; Hoshino, Yumi; Sato, Eimei

    2007-12-01

    The objective of this study was to develop an ideal freezing extender and method for rat epididymal sperm cryopreservation. Epididymal sperm collected from 30 Wistar males was frozen, and experiments were conducted to study its post-thaw characteristics when freezing with raffinose-free buffer or various concentrations of raffinose and egg yolk dissolved in distilled and deionised water, PBS, or modified Krebs-Ringer bicarbonate (mKRB)-based extender. Different concentrations of glycerol, Equex STM, or sodium dodecyl sulfate (SDS) dissolved in either PBS or mKRB containing egg yolk were also tested. Based on the data from these experiments, further experiments tested how different sugars such as raffinose, trehalose, lactose, fructose, and glucose dissolved in mKRB with Equex STM, SDS and egg yolk supplementation affected the post-thaw characteristics of cryopreserved sperm. Cryosurvival of frozen-thawed sperm were judged by microscopic assessment of the sperm motility index (SMI), and acrosome integrity was measured using FITC-PNA staining. Thawed sperm were subjected to 3h of a thermal resistance test. Beneficial effects on the post-thaw survival of sperm were obtained when 0.1M raffinose in mKRB was used with 0.75% Equex STM, 0.05% SDS, and 20% egg yolk. Sperm cryopreserved with this treatment exhibited a higher motility index and maintained greater SMI and acrosome integrity throughout incubation when compared to sperm frozen in various concentrations of other cryoprotectants and trehalose, lactose, fructose, glucose. In conclusion, cryopreservation in an extender solution of raffinose dissolved in mKRB containing Equex STM, SDS and egg yolk greatly enhances the freezability of rat epididymal sperm. PMID:17923121

  11. Buffered Electrochemical Polishing of Niobium

    SciTech Connect

    Gianluigi Ciovati, Hui Tian, Sean Corcoran

    2011-03-01

    The standard preparation of superconducting radio-frequency (SRF) cavities made of pure niobium include the removal of a 'damaged' surface layer, by buffered chemical polishing (BCP) or electropolishing (EP), after the cavities are formed. The performance of the cavities is characterized by a sharp degradation of the quality factor when the surface magnetic field exceeds about 90 mT, a phenomenon referred to as 'Q-drop'. In cavities made of polycrystalline fine grain (ASTM 5) niobium, the Q-drop can be significantly reduced by a low-temperature ({approx} 120 C) 'in-situ' baking of the cavity if the chemical treatment was EP rather than BCP. As part of the effort to understand this phenomenon, we investigated the effect of introducing a polarization potential during buffered chemical polishing, creating a process which is between the standard BCP and EP. While preliminary results on the application of this process to Nb cavities have been previously reported, in this contribution we focus on the characterization of this novel electrochemical process by measuring polarization curves, etching rates, surface finish, electrochemical impedance and the effects of temperature and electrolyte composition. In particular, it is shown that the anodic potential of Nb during BCP reduces the etching rate and improves the surface finish.

  12. Flotation of sodium carbonate and sodium bicarbonate salts from their saturated brines

    Microsoft Academic Search

    O Ozcan; J. D Miller

    2002-01-01

    The flotation behavior of sodium carbonates and sodium bicarbonate has been studied with dodecyl amine hydrochloride (DAH) and sodium dodecyl sulfate (SDS) as part of a research program to evaluate the potential of flotation technology for use in the trona industry. Laboratory microflotation experiments generally show that flotation of sodium carbonate salts is possible at least to some extent with

  13. Association of erosive esophagitis with Helicobacter pylori eradication: a role of salivary bicarbonate and glycoprotein secretion.

    PubMed

    Namiot, D B; Namiot, Z; Markowski, A R; Leszczy?ska, K; Bucki, R; Kemona, A; Go?ebiewska, M

    2009-01-01

    In some populations, Helicobacter pylori eradication is associated with development of erosive esophagitis. The aim of this study was to evaluate the contribution of salivary bicarbonate and glycoprotein secretion to the pathogenesis of erosive esophagitis developing after H. pylori eradication. Gastroscopy and saliva collection were performed at recruitment and 12 months after completion of eradication therapy. Eighty-eight patients with duodenal ulcer were recruited to the study. Erosive esophagitis was found in 13 patients (grade A, 8 patients; grade B, 4 patients; grade C, 1 patient). Among the 74 subjects who completed the study, erosive esophagitis was detected in 21 patients (grade A, 15 patients; grade B, 6 patients); they all were successfully eradicated. Bicarbonate and glycoprotein secretion was not found to differ significantly between the subjects with and without erosive esophagitis both before and 1 year after H. pylori eradication. However, it was lower in H. pylori-infected (baseline) than in H. pylori-noninfected erosive esophagitis subjects (1 year after successful eradication) (bicarbonate 2.34 [1.29-3.40)]vs. 3.64 [2.70-4.58]micromol/min and glycoprotein 0.23 [0.15-0.31]vs. 0.35 [0.28-0.43] mg/min, P= 0.04 and P= 0.04, respectively). We conclude that changes in salivary bicarbonate and glycoprotein secretion related to H. pylori eradication do not promote the development of erosive esophagitis in duodenal ulcer patients. PMID:19222537

  14. Effect of Prepartum Energy, Body Condition, and Sodium Bicarbonate on Production of Cows in Early Lactation

    Microsoft Academic Search

    Y. Boisclair; D. G. Grieve; J. B. Stone; O. B. Allen; G. K. Macleod

    1986-01-01

    In trial 1, the effects of dietary energy (102, 131 or 162% of requirement) in the dry period and of sodium bicarbonate (0 or .75% of diet dry matter) in early lactation were assessed with 31 cows in a 3 × 2 factorial arrangement of treatments. Body condition and weight increased linearly with prepartum energy. Dry matter intake and milk

  15. Experimental Tricyclic Antidepressant Toxicity: A Randomized, Controlled Comparison of Hypertonic Saline Solution, Sodium Bicarbonate, and Hyperventilation

    Microsoft Academic Search

    James L McCabe; Daniel J Cobaugh; James J Menegazzi; John Fata

    1998-01-01

    Study objective: We sought to compare the effects of hypertonic sodium chloride solution (HTS), sodium bicarbonate solution, and hyperventilation (HV) on severe tricyclic antidepressant (TCA) toxicity in a swine model. Methods: Twenty-four mixed-breed, domestic swine of either sex were given an intravenous infusion of nortriptyline (NT) until development of both a QRS duration longer than 120 ms and a systolic

  16. Control of blue mold of apple by combining controlled atmosphere, antagonist mixtures and sodium bicarbonate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'Golden Delicious' apples were wound-inoculated with Penicillium expansum, treated with various combinations of sodium bicarbonate and two antagonists, and stored in air or controlled atmosphere (1.4% O2, 3% CO2). The fruit were stored for 2 or 4 months at 1°C. The antagonists survived and their p...

  17. Evolutionary aspects of intestinal bicarbonate secretion in fish Josi R. Taylor , Martin Grosell

    E-print Network

    Grosell, Martin

    Evolutionary aspects of intestinal bicarbonate secretion in fish Josi R. Taylor , Martin Grosell January 2006; accepted 16 January 2006 Abstract Experiments compared intestinal HCO3 - secretion in the intestine of marine teleost Gulf toadfish, Opsanus beta, to representatives of early chondrostean

  18. CONTROL OF BLUE MOLD OF APPLE BY COMBINING CONTROLLED ATMOSPHERE, ANTAGONIST MIXTURES, AND SODIUM BICARBONATE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'Golden Delicious' apples were wound-inoculated with Penicillium expansum treated with various combinations of sodium bicarbonate and two antagonists, and stored in air or controlled atmosphere (1.4% O2, 3% CO fruit were stored for 4 months at 1ºC. The antagonists survived and their populations inc...

  19. Evaluation of the sorin bicarbon bileaflet valve in 488 patients (519 prostheses)

    Microsoft Academic Search

    Ira Goldsmith; Gregory Y. H Lip; Ramesh L Patel

    1999-01-01

    The Sorin bicarbon bileaflet prosthesis was introduced in 1990. To evaluate the clinical performance of this prosthesis, we reviewed 519 prostheses that were implanted in 488 patients (275 men, 213 women; mean age 59 years; SD 10.8, range 19 to 88) from 1993 to 1997. Preoperatively, 82% of patients were in New York Heart Association (NYHA) functional class III or

  20. Oxidation of ammonium sulfite in aqueous solutions using ozone technology

    NASA Astrophysics Data System (ADS)

    Li, Yue; Shang, Kefeng; Lu, Na; Li, Jie; Wu, Yan

    2013-03-01

    How to deal with unstable ammonium sulfite, the byproduct of flue gas desulfuration by ammonia absorption methods, has been a difficult problem in recent years. Oxidation of ammonium sulfite in aqueous solutions using ozone produced by a surface discharge system was investigated in the paper. The oxidation efficiency of ammonium sulfite by ozone and traditional air aeration were compared, and the factors including ozone concentration, gas flow rate, initial concentration of ammonium sulfite solution and reaction temperature were discussed. The results show that the oxidation efficiency of ammonium sulfite by ozone technology reached nearly 100% under the optimum conditions, which had a significant increase compared with that by air aeration.

  1. Bedrock Nitrogen and Hydrothermal Ammonium in Yellowstone National Park, WY, USA

    NASA Astrophysics Data System (ADS)

    Holloway, J. M.; Bohlke, J. K.; Nordstrom, D. K.

    2003-12-01

    High ammonium concentrations in some of the hot springs of Yellowstone National Park (up to 880 mg L-1 as N at Washburn Hot Springs) have been attributed to leaching of sedimentary rock by hydrothermal solutions. However, relatively little is known about the direct relationship between rock geochemistry in volcanic centers and nitrogen in thermal waters. For this study, a suite of core samples from US Geological Survey drill holes in Yellowstone National Park were characterized for nitrogen and carbon in different lithologies. These data were related to the aqueous geochemistry and ? 15N-NH4+ of thermal waters in different hot spring basins in the park to better understand the water-rock interactions. Core samples selected for study included tuff, water-reworked volcanic sediments, glacial sediment, lacustrine sedimentary rock, and marine sedimentary rock. Substantial amounts of nitrogen were present in all bedrock types, with the highest nitrogen concentrations measured in marine sedimentary rocks (430-830 mg N kg-1) from Y10, which is located at Mammoth Hot Springs. Although the underlying bedrock has elevated nitrogen concentrations, hydrothermal ammonium concentrations at Mammoth Hot Springs are relatively low (~1 mg L-1 as N). These solutions are buffered by carbonate (pH >8) and may have lost some N by volatilization as ammonia gas. Thermal waters in Norris Geyser Basin are acid to circumneutral with ammonium concentrations ranging from <0.03 to 80 mg L-1 as N. Nitrogen in tuffs (400-620 mg N kg-1) from drill holes Y9 and Y12 at Norris Geyser Basin may be present as a result of ammonium partitioning from solution to zeolites or other secondary minerals. Thermal waters sampled at Mammoth, Norris, and other geyser basins in the park varied widely in ammonium concentrations and isotopic compositions (? 15N), from <0.3 to 450 mg L-1 as N and -5 to +25‰ , respectively. The isotope data are interpreted to reflect multiple processes, including leaching of nitrogen from sedimentary sources, partitioning of ammonium from solution to secondary minerals, with fractionations resulting from boiling and steam distillation of ammonia gas.

  2. Detonation Properties of Ammonium Dinitramide (ADN)

    NASA Astrophysics Data System (ADS)

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

    1999-06-01

    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.

  3. Buffer strips in composites at elevated temperature

    NASA Technical Reports Server (NTRS)

    Bigelow, C. A.

    1983-01-01

    The composite material 'buffer strip' concept is presently investigated at elevated temperatures for the case of graphite/polyimide buffer strip panels using a (45/0/45/90)2S layup, where the buffer strip material was 0-deg S-glass/polyimide. Each panel was loaded in tension until it failed, and radiographs and crack opening displacements were recorded during the tests to determine fracture onset, fracture arrest, and the extent of damage in the buffer strip after crack arrest. At 177 + or - 3 C, the buffer strips increased the panel strength by at least 40 percent in comparison with panels without buffer strips. Compared to similar panels tested at room temperature, those tested at elevated temperature had lower residual strengths, but higher failure strains.

  4. Optical constants of concentrated aqueous ammonium sulfate.

    NASA Technical Reports Server (NTRS)

    Remsberg, E. E.

    1973-01-01

    Using experimental data obtained from applying spectroscopy to a 39-wt-% aqueous ammonium sulfate solution, it is shown that, even though specific aerosol optical constants appear quite accurate, spectral variations may exist as functions of material composition or concentration or both. Prudent users of optical constant data must then include liberal data error estimates when performing calculations or in interpreting spectroscopic surveys of collected aerosol material.

  5. Equation of State of Ammonium Nitrate

    NASA Astrophysics Data System (ADS)

    Robbins, David L.; Sheffield, Stephen A.; Dattelbaum, Dana M.; Velisavljevic, Nenad; Stahl, David B.

    2009-12-01

    Ammonium nitrate (AN) is a widely used fertilizer and mining explosive. AN is commonly used in ammonium nitrate-fuel oil (ANFO), which is a mixture of explosive-grade AN prills and fuel oil in a 94:6 ratio by weight. ANFO is a non-ideal explosive with measured detonation velocities around 4 km/s. The equation of state properties and known initiation behavior of neat AN are limited. We present the results of a series of gas gun-driven plate impact experiments on pressed neat ammonium nitrate at 1.72 g/cm3. No evidence of initiation was observed under shock loading to 22 GPa. High pressure x-ray diffraction experiments in diamond anvil cells provided insight into the high pressure phase behavior over the same pressure range (to 25 GPa), as well as a static isotherm at ambient temperature. From the isotherm and thermodynamic properties at ambient conditions, a preliminary unreacted equation of state (EOS) has been developed based on the Murnaghan isotherm and Helmholtz formalism [1], which compares favorably with the available experimental Hugoniot data on several densities of AN.

  6. DETECTION OF THE AMMONIUM ION IN SPACE

    SciTech Connect

    Cernicharo, J.; Tercero, B. [Deparment of Astrophysics, CAB, INTA-CSIC, Crta Torrejon-Ajalvir Km 4, E-28850 Torrejon de Ardoz, Madrid (Spain); Fuente, A. [Observatorio Astronomico Nacional, Apdo. 112, E-28803 Alcala de Henares (Spain); Domenech, J. L.; Cueto, M.; Carrasco, E.; Herrero, V. J.; Tanarro, I. [Instituto de Estructura de la Materia, IEM-CSIC, Serrano 123, E-28006 Madrid (Spain); Marcelino, N. [NRAO, 520 Edgemont Road, Charlottesville, VA 22902 (United States); Roueff, E. [Luth, Observatoire de Paris, CNRS UMR8102, Place J. Janssen F-92190 Meudon (France); Gerin, M. [LERMA, Observatoire de Paris, CNRS UMR8112 and Ecole Normale Superieure, 61 Avenue de lObservatoire, F-75014 Paris (France); Pearson, J., E-mail: jcernicharo@cab.inta-csic.es [Jet Propulsion Laboratory, 4800 Oak Grove Drive, MC 168-314, Pasadena, CA 91109 (United States)

    2013-07-01

    We report on the detection of a narrow feature at 262816.73 MHz toward Orion and the cold prestellar core B1-bS which we attribute to the 1{sub 0}-0{sub 0} line of the deuterated ammonium ion, NH{sub 3}D{sup +}. The observations were performed with the IRAM 30 m radio telescope. The carrier has to be a light molecular species as it is the only feature detected over 3.6 GHz of bandwidth. The hyperfine structure is not resolved, indicating a very low value for the electric quadrupolar coupling constant of nitrogen which is expected for NH{sub 3}D{sup +} as the electric field over the N nucleus is practically zero. Moreover, the feature is right at the predicted frequency for the 1{sub 0}-0{sub 0} transition of the ammonium ion, 262817 {+-} 6 MHz (3{sigma}), using rotational constants derived from new infrared data obtained in our laboratory in Madrid. The estimated column density is (1.1 {+-} 0.2) Multiplication-Sign 10{sup 12} cm{sup -2}. Assuming a deuterium enhancement similar to that of NH{sub 2}D, we derive N(NH{sub 4}{sup +}) {approx_equal} 2.6 Multiplication-Sign 10{sup 13} cm{sup -2}, i.e., an abundance for ammonium of a few 10{sup -11}.

  7. Antimicrobial activity of borate-buffered solutions.

    PubMed Central

    Houlsby, R D; Ghajar, M; Chavez, G O

    1986-01-01

    A minimal salts medium adjusted to physiological pH and osmolality was buffered with either 0.3% phosphate or 1.2% borate and evaluated for antimicrobial activity. The borate-buffered medium, either with or without a carbon source, exhibited significant antimicrobial activity against 15 Pseudomonas strains, 12 strains of enteric bacteria, and 7 strains of staphylococci. The borate-buffered system appears suitable for use as a generic vehicle for ophthalmic pharmaceutical agents. PMID:3729341

  8. Buffers Strips, Common-Sense Conservation

    NSDL National Science Digital Library

    This recent publication from the Natural Resources Conservation Service (NRCS) and the National Conservation Buffer Team focuses on the practices, agricultural programs, and national programs that promote conservation buffers -- "strips or small areas of land in permanent vegetation" to help control potential pollutants and other environmental concerns. NRCS outlines specific programs and educational initiatives for many different types of "filter strips, field borders, grassed waterways, field windbreaks, shelterbelts, contour grass strips, and riparian (streamside) buffers."

  9. Riparian buffers and potentially unstable ground

    Microsoft Academic Search

    Swee May Tang; David R. Montgomery

    1995-01-01

    The spatial coincidence between riparian buffers of various widths and extents and potentially unstable ground was quantified\\u000a using a physically based model for shallow landslide initiation and GIS for two watersheds on the Olympic Peninsula, Washington,\\u000a USA. The proportion of the potentially unstable ground in each watershed within riparian buffers is a function of both buffer\\u000a width and the extent

  10. Unit 8: Buffers for Biochemical Reactions

    NSDL National Science Digital Library

    The last of an eight-unit teaching and training module from Promega, this "introductory buffers laboratory is for use in undergraduate or highschool courses that cover basic topics in molecular biology or biochemistry" and includes "laboratories to illustrate basic chemistry concepts related to buffers and their functions." This unit is math-intensive, aimed at helping students feel comfortable performing laboratory calculations. It includes a lecture presentation ("Buffers for Biological Systems") and a students' and instructors' laboratory protocol.

  11. Buffer system for the separation of neutral and charged small molecules using micellar electrokinetic chromatography with mass spectrometric detection.

    PubMed

    Goetzinger, Wolfgang K; Cai, Hong

    2005-06-24

    An organic buffer system will be discussed that is suitable for the separation of neutral as well as charged molecules be means of micellar electrokinetic chromatography (MEKC). The buffers are based on the combination of a long chain alkyl acid, such as lauric acid with ammonium hydroxide or an organic base such as tris-hydroxymethylaminomethane (Tris). The resulting buffer system is able to separate neutral compounds based on its micellar properties. These buffers exhibit much reduced conductivity compared to traditional MEKC buffers, such as sodium dodecylsulfate (SDS), which contain inorganic salts. They also have inherent buffer capacity at high pH resulting from the basic buffer component, which in our studies had pK values from about 8-11. The separations that were observed showed high efficiency with plate counts in many cases above 500,000 plates per meter. The reduced conductivity allowed for the application of much higher electric fields, resulting in very fast analysis times. Alternatively, an increase in detection sensitivity could be achieved, as the reduced conductivity allowed for the use of capillaries with lager internal diameters. Combinations of different alkyl acids and organic bases provided for significant flexibility in selectivity tuning. Finally, the fact that the organic micellar buffer systems discussed here do not contain inorganic ions, allows for coupling with mass spectrometric (MS) detection. The possibility of MS detection combined with the high speed in analysis that can be obtained using these organic buffer systems, could make this approach an interesting option for high throughput analysis of combinatorial libraries. PMID:16038325

  12. All-optical buffering for DPSK packets

    NASA Astrophysics Data System (ADS)

    Liu, Guodong; Wu, Chongqing; Liu, Lanlan; Wang, Fu; Mao, Yaya; Sun, Zhenchao

    2013-12-01

    Advanced modulation formats, such as DPSK, DQPSK, QAM, have become the mainstream technologies in the optical network over 40Gb/s, the DPSK format is the fundamental of all advanced modulation formats. Optical buffers, as a key element for temporarily storing packets in order to synchronization or contention resolution in optical nodes, must be adapted to this new requirement. Different from other current buffers to store the NRZ or RZ format, an all-optical buffer of storing DPSK packets based on nonlinear polarization rotation in SOA is proposed and demonstrated. In this buffer, a section of PMF is used as fiber delay line to maintain the polarization states unchanged, the driver current of SOA is optimized, and no amplifier is required in the fiber loop. A packet delay resolution of 400ns is obtained and storage for tens rounds is demonstrated without significant signal degradation. Using proposed the new tunable DPSK demodulator, bit error rate has been measured after buffering for tens rounds for 10Gb/s data payload. Configurations for First-in First-out (FIFO) buffer or First-in Last-out (FILO) buffer are proposed based on this buffer. The buffer is easy control and suitable for integration. The terminal contention caused by different clients can be mitigated by managing packets delays in future all-optical network, such as optical packet switching network and WDM switching network.

  13. SODR Memory Control Buffer Control ASIC

    NASA Technical Reports Server (NTRS)

    Hodson, Robert F.

    1994-01-01

    The Spacecraft Optical Disk Recorder (SODR) is a state of the art mass storage system for future NASA missions requiring high transmission rates and a large capacity storage system. This report covers the design and development of an SODR memory buffer control applications specific integrated circuit (ASIC). The memory buffer control ASIC has two primary functions: (1) buffering data to prevent loss of data during disk access times, (2) converting data formats from a high performance parallel interface format to a small computer systems interface format. Ten 144 p in, 50 MHz CMOS ASIC's were designed, fabricated and tested to implement the memory buffer control function.

  14. Bidirectional diffusion of ammonium and sodium cations in forward osmosis: role of membrane active layer surface chemistry and charge.

    PubMed

    Lu, Xinglin; Boo, Chanhee; Ma, Jun; Elimelech, Menachem

    2014-12-16

    Systematic fundamental understanding of mass transport in osmosis-driven membrane processes is important for further development of this emerging technology. In this work, we investigate the role of membrane surface chemistry and charge on bidirectional solute diffusion in forward osmosis (FO). In particular, bidirectional diffusion of ammonium (NH4(+)) and sodium (Na(+)) is examined using FO membranes with different materials and surface charge characteristics. Using an ammonium bicarbonate (NH4HCO3) draw solution, we observe dramatically enhanced cation fluxes with sodium chloride feed solution compared to that with deionized water feed solution for thin-film composite (TFC) FO membrane. However, the bidirectional diffusion of cations does not change, regardless of the type of feed solution, for cellulose triacetate (CTA) FO membrane. We relate this phenomenon to the membrane fixed surface charge by employing different feed solution pH to foster different protonation conditions for the carboxyl groups on the TFC membrane surface. Membrane surface modification is also carried out with the TFC membrane using ethylenediamine to alter carboxyl groups into amine groups. The modified TFC membrane, with less negatively charged groups, exhibits a significant decrease in the bidirectional diffusion of cations under the same conditions employed with the pristine TFC membrane. Based on our experimental observations, we propose Donnan dialysis as a mechanism responsible for enhanced bidirectional diffusion of cations in TFC membranes. PMID:25418020

  15. Preparation of Y2O3:Eu3+, Tb3+ nanopowders with tunable luminescence by ammonium bicarbonate co-precipitation method

    NASA Astrophysics Data System (ADS)

    Shi, Hui; Zhang, Xi-Yan; Wang, Neng-Li; Dong, Wei-Li; Mi, Xiao-Yun

    2015-09-01

    Y2O3:Eu3+, Tb3+ nanopowders were prepared by co-precipitation method with NH4HCO3 as precipitant. The nanopowders with different calcined temperatures and Eu3+/Tb3+ doped ratio were characterized by X-ray Diffraction (XRD), scanning electron microscopy (SEM) and fluorescence spectrophotometer. The results showed that the nanopowders calcined at 1100°C for 2 h had a uniform distribution, high purity and good dispersibility. The particle size was in the range of 60-80 nm. The excitation spectra of Eu3+/Tb3+ co-doped phosphors were wide. The phosphors could emit the green light at the peak of 543 nm and the red light at the peak of 611 nm simultaneously under 276 nm or 300 nm excited. Because of the energy transfer between Tb3+ and Eu3+, the 543 nm emission of Tb3+ ion was weakened while the 611 nm emission of Eu3+ enhanced. The emissive colors of Y2O3:Eu3+, Tb3+ nanopowders could be adjusted from yellow-green to orange-red by changing the Eu3+/Tb3+ doping ratio.

  16. Bicarbonate stimulates the electron donation from Mn²? to P???? in isolated D1/D2/cytochrome b559 complex.

    PubMed

    Zharmukhamedov, S K; Allakhverdiev, S I; Smolova, T N; Klimov, V V

    2013-12-01

    Influence of bicarbonate on the efficiency of the electron donation from Mn(2+) to P???(+) in isolated D1/D2/cytochrome b559 complex was investigated. All the experiments were carried out in a medium depleted of HCO?(-)/CO?. Kinetics of photoinduced absorbance changes (?A) at different wavelengths and decrease of chlorophyll fluorescence yield (-?F) related to photoaccumulation of reduced pheophytin, the intermediary electron acceptor of photosystem II (PSII), in the presence of Mn(2+) under anaerobic conditions were measured. Addition of bicarbonate (1 mM) increased the amplitude of these ?A and -?F at least by a factor of 3. Measurements of the photoinduced ?A, related to photooxidation of the primary electron donor of PSII, chlorophyll P???, were done in the presence of silicomolybdate as electron acceptor. These results show that the addition of 0.05 mM Mn(2+) alone or jointly with 1 mM bicarbonate induces a 20% and 70%-decrease of the magnitude of the ?A at 680 nm. The effect of Mn(2+) (in the presence and absence of bicarbonate) was completely eliminated by the addition of 12 mM EDTA. All these bicarbonate effects were not observed if MgCl? or formate were used instead of MnCl? and bicarbonate, respectively. In the absence of Mn(2+), bicarbonate induced none of the mentioned above effects (increase of photoaccumulation of reduced pheophytin and decrease of photooxidation of P680). The presented data suggest that bicarbonate stimulates the electron donation from Mn(2+) to D1/D2/cyt b559 reaction center evidently due to formation of easily oxidizable Mn-bicarbonate complexes. PMID:24201105

  17. Serum Bicarbonate Levels and the Progression of Kidney Disease: A Cohort Study

    PubMed Central

    Shah, Samir N.; Abramowitz, Matthew; Hostetter, Thomas H.; Melamed, Michal L.

    2015-01-01

    Background Animal models of kidney disease have linked metabolic acidosis with renal damage. The role of low serum bicarbonate levels in kidney disease progression in humans has not been studied. Study Design Retrospective cohort study. Setting & Participants: Adults visiting a medical clinic in the Bronx, NY from 01/01/01 to 12/31/03 were included in the study (n=5,422) and followed until 6/30/07 Predictor Serum bicarbonate levels Outcomes Kidney disease progression was defined as either a decline in the estimated glomerular filtration rate (eGFR) by 50% or reaching an eGFR of <15 ml/min/1.73m2 (n=337). Measurements Patients’ baseline demographics, comorbidities, laboratory data and socioeconomic status were recorded. Serial outpatient serum creatinines were collected (median, 5 measurements/ person). Results The mean age was 52 years, 69% were women, 45% were African-American, 31% were Hispanic, 21% had diabetes mellitus, 41% had hypertension, and 9% had a baseline eGFR <60 ml/min/1.73m2. Kidney disease progressed by the definition above in 337 patients (6.2%). Compared to the reference group (bicarbonate level 25-26 mEq/L), the hazard ratio for progression after adjustment for potential confounders was 1.54 (95% CI 1.13-2.09) for bicarbonate levels ?22 mEq/L, 0.97 (95% CI 0.70-1.35) for levels 23-24 mEq/L and 1.14 (95% CI 0.84-1.55) for levels ?27 mEq/L. (Global p-value for inclusion of serum bicarbonate in the model, 0.01). These results remained similar when using different definitions of the outcome (an eGFR decline by 30%, 1288 outcomes (24%)) or doubling of serum creatinine (268 outcomes (4.9%)). Limitations Data used in study was collected for clinical, not research, purposes. Conclusions Low serum bicarbonate is associated with the progression of kidney disease, independent of baseline eGFR and other clinical, demographic and socioeconomic factors. Prospective studies are needed to confirm this relationship and to evaluate the efficacy of alkali supplements for slowing progression. PMID:19394734

  18. Sodium Bicarbonate Treatment during Transient or Sustained Lactic Acidemia in Normoxic and Normotensive Rats

    PubMed Central

    Valenza, Franco; Pizzocri, Marta; Salice, Valentina; Chevallard, Giorgio; Fossali, Tommaso; Coppola, Silvia; Froio, Sara; Polli, Federico; Gatti, Stefano; Fortunato, Francesco; Comi, Giacomo P.; Gattinoni, Luciano

    2012-01-01

    Introduction Lactic acidosis is a frequent cause of poor outcome in the intensive care settings. We set up an experimental model of lactic acid infusion in normoxic and normotensive rats to investigate the systemic effects of lactic acidemia per se without the confounding factor of an underlying organic cause of acidosis. Methodology Sprague Dawley rats underwent a primed endovenous infusion of L(+) lactic acid during general anesthesia. Normoxic and normotensive animals were then randomized to the following study groups (n?=?8 per group): S) sustained infusion of lactic acid, S+B) sustained infusion+sodium bicarbonate, T) transient infusion, T+B transient infusion+sodium bicarbonate. Hemodynamic, respiratory and acid-base parameters were measured over time. Lactate pharmacokinetics and muscle phosphofructokinase enzyme's activity were also measured. Principal Findings Following lactic acid infusion blood lactate rose (P<0.05), pH (P<0.05) and strong ion difference (P<0.05) drop. Some rats developed hemodynamic instability during the primed infusion of lactic acid. In the normoxic and normotensive animals bicarbonate treatment normalized pH during sustained infusion of lactic acid (from 7.22±0.02 to 7.36±0.04, P<0.05) while overshoot to alkalemic values when the infusion was transient (from 7.24±0.01 to 7.53±0.03, P<0.05). When acid load was interrupted bicarbonate infusion affected lactate wash-out kinetics (P<0.05) so that blood lactate was higher (2.9±1 mmol/l vs. 1.0±0.2, P<0.05, group T vs. T+B respectively). The activity of phosphofructokinase enzyme was correlated with blood pH (R2?=?0.475, P<0.05). Conclusions pH decreased with acid infusion and rose with bicarbonate administration but the effects of bicarbonate infusion on pH differed under a persistent or transient acid load. Alkalization affected the rate of lactate disposal during the transient acid load. PMID:23029373

  19. Supramolecular buffering by ring-chain competition.

    PubMed

    Paffen, Tim F E; Ercolani, Gianfranco; de Greef, Tom F A; Meijer, E W

    2015-02-01

    Recently, we reported an organocatalytic system in which buffering of the molecular catalyst by supramolecular interactions results in a robust system displaying concentration-independent catalytic activity. Here, we demonstrate the design principles of the supramolecular buffering by ring-chain competition using a combined experimental and theoretical approach. Our analysis shows that supramolecular buffering of a molecule is caused by its participation as a chain stopper in supramolecular ring-chain equilibria, and we reveal here the influence of various thermodynamic parameters. Model predictions based on independently measured equilibrium constants corroborate experimental data of several molecular systems in which buffering occurs via competition between cyclization, growth of linear chains, and end-capping by the chain-stopper. Our analysis reveals that the effective molarity is the critical parameter in optimizing the broadness of the concentration regime in which supramolecular ring-chain buffering occurs as well as the maximum concentration of the buffered molecule. To conclude, a side-by-side comparison of supramolecular ring-chain buffering, pH buffering, and molecular titration is presented. PMID:25581227

  20. Color image quantization for frame buffer display

    Microsoft Academic Search

    Paul Heckbert

    1982-01-01

    Algorithms for adaptive, tapered quantization of color images are described. The research is motivated by the desire to display high-quality reproductions of color images with small frame buffers. It is demonstrated that many color images which would normally require a frame buffer having 15 bits per pixel can be quantized to 8 or fewer bits per pixel with little subjective

  1. Buffered Steiner trees for difficult instances

    Microsoft Academic Search

    Charles J. Alpert; Miloš Hrki?; Jiang Hu; Andrew B. Kahng; John Lillis; Bao Liu; Stephen T. Quay; Sachin S. Sapatnekar; A. J. Sullivan; Paul Villarrubia

    2001-01-01

    Buffer insertion has become an increasingly critical optimization in high performance design. The problem of finding a delay-optimal buffered Steiner tree has been an active area of research, and excellent solutions exist for most instances. However, current approaches fail to adequately solve a particular class of real-world “difficult” instances which are characterized by a large number of sinks, variations in

  2. UNDERSTANDING, DERIVING, AND COMPUTING BUFFER CAPACITY

    EPA Science Inventory

    Derivation and systematic calculation of buffer capacity is a topic that seems often to be neglected in chemistry courses and given minimal treatment in most texts. However, buffer capacity is very important in the chemistry of natural waters and potable water. It affects corro...

  3. FIFO Buffer for Asynchronous Data Streams

    NASA Technical Reports Server (NTRS)

    Bascle, K. P.

    1985-01-01

    Variable-rate, asynchronous data signals from up to four measuring instruments or other sources combined in first-in/first-out (FIFO) buffer for transmission on single channel. Constructed in complementary metal-oxide-semiconductor (CMOS) logic, buffer consumes low power (only 125 mW at 5V) and conforms to aerospace standards of reliability and maintainability.

  4. Understanding the Science Behind Riparian Forest Buffers

    E-print Network

    Liskiewicz, Maciej

    a Understanding the Science Behind Riparian Forest Buffers: Effects on Plant and Animal Communities, Virginia Tech, 324 Cheatham Hall, Blacksburg, VA 24061 Understanding the Science Behind Riparian Forest Buffers: Effects on Plant and Animal Communities by Julia C. Klapproth and James E. Johnson* The riparian

  5. Understanding the Science Behind Riparian Forest Buffers

    E-print Network

    Liskiewicz, Maciej

    Understanding the Science Behind Riparian Forest Buffers: Benefits to Communities and Landowners, Virginia Tech, 324 Cheatham Hall, Blacksburg, VA 24061 Understanding the Science Behind Riparian Forest Buffers: Benefits to Communities and Landowners by Julia C. Klapproth and James E. Johnson* The riparian

  6. Understanding the Science Behind Riparian Forest Buffers

    E-print Network

    Liskiewicz, Maciej

    Understanding the Science Behind Riparian Forest Buffers: Planning, Establishment, and Maintenance Riparian Forest Buffers: Planning, Establishment, and Maintenance by Julia C. Klapproth and James E. Johnson* The riparian area is that area of land located immediately adjacent to streams, lakes, or other

  7. The buffer capacity of airway epithelial secretions

    PubMed Central

    Kim, Dusik; Liao, Jie; Hanrahan, John W.

    2014-01-01

    The pH of airway epithelial secretions influences bacterial killing and mucus properties and is reduced by acidic pollutants, gastric reflux, and respiratory diseases such as cystic fibrosis (CF). The effect of acute acid loads depends on buffer capacity, however the buffering of airway secretions has not been well characterized. In this work we develop a method for titrating micro-scale (30 ?l) volumes and use it to study fluid secreted by the human airway epithelial cell line Calu-3, a widely used model for submucosal gland serous cells. Microtitration curves revealed that HCO?3 is the major buffer. Peak buffer capacity (?) increased from 17 to 28 mM/pH during forskolin stimulation, and was reduced by >50% in fluid secreted by cystic fibrosis transmembrane conductance regulator (CFTR)-deficient Calu-3 monolayers, confirming an important role of CFTR in HCO?3 secretion. Back-titration with NaOH revealed non-volatile buffer capacity due to proteins synthesized and released by the epithelial cells. Lysozyme and mucin concentrations were too low to buffer Calu-3 fluid significantly, however model titrations of porcine gastric mucins at concentrations near the sol-gel transition suggest that mucins may contribute to the buffer capacity of ASL in vivo. We conclude that CFTR-dependent HCO?3 secretion and epithelially-derived proteins are the predominant buffers in Calu-3 secretions. PMID:24917822

  8. Buffer Management Simulation in ATM Networks

    NASA Technical Reports Server (NTRS)

    Yaprak, E.; Xiao, Y.; Chronopoulos, A.; Chow, E.; Anneberg, L.

    1998-01-01

    This paper presents a simulation of a new dynamic buffer allocation management scheme in ATM networks. To achieve this objective, an algorithm that detects congestion and updates the dynamic buffer allocation scheme was developed for the OPNET simulation package via the creation of a new ATM module.

  9. African American College Women's Suicide Buffers.

    ERIC Educational Resources Information Center

    Marion, Michelle S.; Range, Lillian M.

    2003-01-01

    To examine the relationships buffers may have with suicide ideation, 300 African American female college students completed measures of suicide ideation and buffers. Three variables accounted for a significant and unique portion of the variance in suicide ideation: family support, a view that suicide is unacceptable, and a collaborative religious…

  10. 46 CFR 58.25-45 - Buffers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Shipping 2 2010-10-01 2010-10-01 false Buffers. 58.25-45 Section 58.25-45 Shipping COAST...MACHINERY AND RELATED SYSTEMS Steering Gear § 58.25-45 Buffers. For each vessel on an ocean, coastwise, or Great...

  11. METAMORPHIC VIRUSES WITH BUILT BUFFER OVERFLOW

    E-print Network

    Stamp, Mark

    METAMORPHIC VIRUSES WITH BUILT BUFFER OVERFLOW The Faculty of the Department of Computer Science of the Requirements for the Degree Master of Computer Science by Ronak Shah Spring 2010 METAMORPHIC VIRUSES WITH BUILT WITH BUILT-IN BUFFER OVERFLOW Metamorphic computer viruses change their structure--and thereby

  12. Ammonium release from a blanket peatland into headwater stream systems.

    PubMed

    Daniels, S M; Evans, M G; Agnew, C T; Allott, T E H

    2012-04-01

    Hydrochemical sampling of South Pennine (UK) headwater streams draining eroded upland peatlands demonstrates these systems are nitrogen saturated, with significant leaching of dissolved inorganic nitrogen (DIN), particularly ammonium, during both stormflow and baseflow conditions. DIN leaching at sub-catchment scale is controlled by geomorphological context; in catchments with low gully densities ammonium leaching dominates whereas highly gullied catchments leach ammonium and nitrate since lower water tables and increased aeration encourages nitrification. Stormflow flux calculations indicate that: approximately equivalent amounts of nitrate are deposited and exported; ammonium export significantly exceeds atmospheric inputs. This suggests two ammonium sources: high atmospheric loadings; and mineralisation of organic nitrogen stored in peat. Downstream trends indicate rapid transformation of leached ammonium into nitrate. It is important that low-order headwater streams are adequately considered when assessing impacts of atmospheric loads on the hydrochemistry of stream networks, especially with respect to erosion, climate change and reduced precipitation. PMID:22285801

  13. High stability buffered phase comparator

    NASA Technical Reports Server (NTRS)

    Adams, W. A.; Reinhardt, V. S. (inventors)

    1984-01-01

    A low noise RF signal phase comparator comprised of two high stability driver buffer amplifiers driving a double balanced mixer which operate to generate a beat frequency between the two RF input signals coupled to the amplifiers from the RF sources is described. The beat frequency output from the mixer is applied to a low noise zero crossing detector which is the phase difference between the two RF inputs. Temperature stability is provided by mounting the amplifiers and mixer on a common circuit board with the active circuit elements located on one side of a circuit board and the passive circuit elements located on the opposite side. A common heat sink is located adjacent the circuit board. The active circuit elements are embedded into the bores of the heat sink which slows the effect of ambient temperature changes and reduces the temperature gradients between the active circuit elements, thus improving the cancellation of temperature effects. The two amplifiers include individual voltage regulators, which increases RF isolation.

  14. Methane production from bicarbonate and acetate in an anoxic marine sediment

    NASA Technical Reports Server (NTRS)

    Crill, P. M.; Martens, C. S.

    1986-01-01

    Methane production from C-14 labeled bicarbonate and acetate was measured over the top 28 cm of anoxic Cape Lookout Bight sediments during the summer of 1983. The depth distribution and magnitude of summed radioisotopically determined rates compare well with previous measurements of total methane production and the sediment-water methane flux. Methane production from CO2 reduction and acetate fermentation accounts for greater than 80 percent of the total production rate and sediment-water flux. Methane production from bicarbonate was found to occur in all depth intervals sampled except those in the top 2 cm, whereas significant methane production from acetate only occurred at depths below 10 cm where sulfate was exhausted. Acetate provided 20 to 29 percent of the measured methane production integrated over the top 30 cm of the sediments.

  15. Transformation of sodium bicarbonate and CO2 into sodium formate over NiPd nanoparticle catalyst

    PubMed Central

    Wang, Mengnan; Zhang, Jiaguang; Yan, Ning

    2013-01-01

    The present research systematically investigated, for the first time, the transformation of sodium bicarbonate and CO2 into sodium formate over a series of Ni based metal nanoparticles (NPs). Ni NPs and eight NiM (M stands for a second metal) NPs were prepared by a facile wet chemical process and then their catalytic performance were evaluated in sodium bicarbonate hydrogenation. Bimetallic NiPd NPs with a composition of 7:3 were found to be superior for this reaction, which are more active than both pure Ni and Pd NPs. Hot filtration experiment suggested the NPs to be the truly catalytic active species and kinetic analysis indicated the reaction mechanism to be different than most homogeneous catalysts. The enhanced activity of the bimetallic nanoparticles may be attributed to their smaller size and improved stability. PMID:24790945

  16. Ammonium Chloride and Ammonium Sulfate for Prevention of Parturient Paresis in Dairy Cows1

    Microsoft Academic Search

    G. R. Oetzel; J. D. Olson; C. R. Curtis; M. J. Fettman

    1988-01-01

    Forty-eight Holstein cows with two or more previous lactations and no history of parturient paresis were randomly assigned to one of four prepartum diets in a 2 x 2 factorial design to determine the effect of dietary supplementation with ammonium salts and Ca intake on serum Ca concentrations at calving. Four diets provided either 53 g total dietary Ca\\/d or

  17. Ammonium dichromate poisoning: A rare cause of acute kidney injury

    PubMed Central

    Radhakrishnan, H.; Gopi, M.; Arumugam, A.

    2014-01-01

    Ammonium dichromate is an inorganic compound frequently used in screen and color printing. Being a strong oxidizing agent, it causes oxygen free radical injury resulting in organ failure. We report a 25-year-old female who presented with acute kidney injury after consumption of ammonium dichromate. She was managed successfully with hemodialysis and supportive measures. This case is reported to highlight the toxicity of ammonium dichromate. PMID:25484533

  18. Physicochemical characterization of corrosion layers formed on iron in a sodium carbonate-bicarbonate containing environment

    Microsoft Academic Search

    J. M. Blengino; M. Keddam; J. P. Labbe; L. Robbiola

    1995-01-01

    Corrosion layers developed on iron in a carbonate-bicarbonate environment in the active-passive potential range have been studied, in relation with Stress Corrosion Cracking (SCC) phenomena, by various physico-chemical techniques: Electrochemical Impedance Spectroscopy (EIS), Infrared Spcctrometry (IRS), Scanning Electron Microscopy (SEM) and Energy Dispersive Spectrometry (EDS). The chemical and electrical natures of the corrosion deposits, as well as surface morphologies, have

  19. Epinephrine and sodium bicarbonate during CPR following asphyxial cardiac arrest in rats

    Microsoft Academic Search

    Robert W. Neumar; Nicholas G. Bircher; Ka Ming Sim; Fung Xiao; Kathy Swales Zadach; Ann Radovsky; Laurence Katz; Ewe Ebmeyer; Peter Safar

    1995-01-01

    Although high-dose epinephrine during CPR improves coronary perfusion pressure (CoPP) and rate of return of spontaneous circulation (ROSC) in some models, its impact on long term outcome (? 72 h) has not been evaluated. Previous studies of sodium bicarbonate (NaHCO3) therapy during CPR indicate that beneficial effects may be dependent on epinephrine (EPI) dose. We hypothesized that EPI and NaHCO3

  20. Effect of cimetidine and sodium bicarbonate on pancreatic replacement therapy in cystic fibrosis

    Microsoft Academic Search

    P R Durie; L Bell; W Linton; M L Corey; G G Forstner

    1980-01-01

    Fifteen patients with cystic fibrosis and pancreatic insufficiency were studied during four randomised seven day treatment periods in which they received only pancreatic supplement (Pancrelipase, 27 capsules per day) or supplement plus cimetidine (20 mg\\/kg body weight\\/24 h) or sodium bicarbonate (15 g\\/m2\\/24 h) alone or in combination. Dietary intake was not fixed but was restricted to foods of known

  1. Evidence for a Detrimental Effect of Bicarbonate Therapy in Hypoxic Lactic Acidosis

    Microsoft Academic Search

    Helmut Graf; William Leach; Allen I. Arieff

    1985-01-01

    Lactic acidosis, a clinical syndrome caused by the accumulation of lactic acid, is characterized by lactate concentration in blood greater than 5 mM. Therapy usually consists of intravenous sodium bicarbonate (NaHCO3), but resultant mortality is greater than 60 percent. The metabolic and systemic effects of NaHCO3 therapy of hypoxic lactic acidosis in dogs were studied and compared to the effects

  2. A sodium bicarbonate-acid powered blow-gun syringe for remote injection of wildlife.

    PubMed

    Lochmiller, R L; Grant, W E

    1983-01-01

    An automatic blow-gun syringe which uses carbon dioxide gas as the injecting force is described. Upon striking the animal, carbon dioxide gas is released by the chemical combination of sodium bicarbonate (baking soda) and acid (vinegar), within the blow-gun syringe. The syringe has been used successfully with captive collared peccaries (Dicotyles tajacu). It has the advantages of longer stability, dependable gas expansion, reduction of drug loss, and consistent drug injection. PMID:6302330

  3. Towards a sustainable synthesis of formate salts: combined catalytic methanol dehydrogenation and bicarbonate hydrogenation.

    PubMed

    Liu, Qiang; Wu, Lipeng; Gülak, Samet; Rockstroh, Nils; Jackstell, Ralf; Beller, Matthias

    2014-07-01

    Formate salts are important chemicals widely used in everyday products. The current industrial-scale manufacture of formates requires CO at high pressure and harsh reaction conditions. Herein, we describe a new process for these products without the utilization of hazardous gases and chemicals. By application of ruthenium pincer complexes, a simultaneous methanol dehydrogenation and bicarbonate hydrogenation reaction proceeds, which provides a green synthesis of formate salts with excellent TON (>18,000), TOF (>1300?h(-1)), and yield (>90%). PMID:24888820

  4. Bicarbonate ingestion has no ergogenic effect on consecutive all out sprint tests in BMX elite cyclists

    Microsoft Academic Search

    Mikel Zabala; Ana B. Peinado; Francisco J. Calderón; Javier Sampedro; Manuel J. Castillo; Pedro J. Benito

    The aim of the present study was to examine the effect of sodium bicarbonate ingestion on consecutive “all out” sprint tests,\\u000a analyzing the acid–base status and its influence on performance and perceived effort. Ten elite bicycle motocross (BMX) riders\\u000a (20.7 ± 1.4 years, training experience 8–12 years) participated in this study which consisted of two trials. Each trial consisted\\u000a of three consecutive Wingate tests

  5. Comparative effects of potassium chloride and bicarbonate on thiazide-induced reduction in urinary calcium excretion

    Microsoft Academic Search

    Lynda A Frassetto; Eileen Nash; R Curtis Morris; Anthony Sebastian

    2000-01-01

    Comparative effects of potassium chloride and bicarbonate on thiazide-induced reduction in urinary calcium excretion.BackgroundThe chronic low-grade metabolic acidosis that occurs in various renal disorders and in normal people, and that is related both to dietary net acid load and age-related renal functional decline, may contribute to osteoporosis by increasing urine calcium excretion. Administration of potassium (K) alkali salts neutralizes acid

  6. Analyzing the revolution of anaerobic ammonium oxidation (anammox) performance and sludge characteristics under zinc inhibition.

    PubMed

    Zhang, Qian-Qian; Zhang, Zheng-Zhe; Guo, Qiong; Wang, Jiao-Jiao; Wang, Hui-Zhong; Jin, Ren-Cun

    2015-04-01

    In the present study, the short- and long-term effects of Zn(II) on the anaerobic ammonium oxidation (anammox) performance and sludge characteristics were evaluated. The anammox activity decreased with increasing Zn(II) concentration and pre-exposure time in short-term tests. The half maximal inhibitory concentration (IC50) of Zn(II) was found to be 25.0 mg L(-1). The 24 and 48-h pre-exposure time was a restricted factor impacting the anammox activity, and washing the inhibited sludge with buffer solution only worked under 0 and 24-h pre-exposure time. The anammox sludge could tolerate 5 mg L(-1) Zn(II) but was suppressed at 8 mg L(-1). The inhibited performance could be remitted, as the combination strategies were applied, and after the short term of recovery period, the inhibited sludge characteristics were remitted to the normal. PMID:25398286

  7. Oxidative modification of native protein residues using cerium(IV) ammonium nitrate.

    PubMed

    Seim, Kristen L; Obermeyer, Allie C; Francis, Matthew B

    2011-10-26

    A new protein modification strategy has been developed that is based on an oxidative coupling reaction that targets electron-rich amino acids. This strategy relies on cerium(IV) ammonium nitrate (CAN) as an oxidation reagent and results in the coupling of tyrosine and tryptophan residues to phenylene diamine and anisidine derivatives. The methodology was first identified and characterized on peptides and small molecules, and was subsequently adapted for protein modification by determining appropriate buffer conditions. Using the optimized procedure, native and introduced solvent-accessible residues on proteins were selectively modified with polyethylene glycol (PEG) and small peptides. This unprecedented bioconjugation strategy targets these under-utilized amino acids with excellent chemoselectivity and affords good-to-high yields using low concentrations of the oxidant and coupling partners, short reaction times, and mild conditions. PMID:21967510

  8. Evidence for ammonium-bearing minerals in Ceres

    NASA Technical Reports Server (NTRS)

    King, T. V. V.; Clark, R. N.; Calvin, W. M.; Sherman, D. M.; Swayze, G. A.; Brown, R. H.

    1991-01-01

    Evidence for ammonium-bearing minerals was found on the surface of the largest asteroid Ceres. The presence of ammonium-bearing clays suggests that Ceres has experienced a period of alteration by substantial amounts of an ammonium-bearing fluid. The presence of the ammonium-bearing clays does not preclude Ceres maintaining a volatile inventory in the core or in a volatile-rich zone at some distance below the surface. Telescopic observations of Ceres, using the 3.0 meter NASA Infrared telescope facility prompted this reevaluation of its surface mineralogy.

  9. 2 Photosystem II and the unique role of bicarbonate: A historical perspective 3 DmitriyQ1 Shevela a,

    E-print Network

    Govindjee

    fix carbon dioxide (CO2) into carbohydrates; this is necessary to 28support life on Earth. Over 50, discovered that there was a definite bicarbonate effect on the electron acceptor 36(the plastoquinone) side

  10. pH adjustment of local anesthetic solutions with sodium bicarbonate: laboratory evaluation of alkalinization and precipitation.

    PubMed

    Peterfreund, R A; Datta, S; Ostheimer, G W

    1989-01-01

    pH adjustment of several commonly administered local anesthetic solutions was evaluated in the laboratory. The pH achieved after the addition of sodium bicarbonate and the onset of precipitation for alkalinized solutions were recorded. Solutions of 2-chloroprocaine and lidocaine readily alkalinized to near physiological pH without precipitation. Mepivacaine solutions exhibited a tendency for delayed precipitation (18-20-minute latency for 1.5% mepivacaine) above neutral pH. Bupivacaine and etidocaine solutions precipitated after the addition of small amounts of sodium bicarbonate and could not be alkalinized to physiologic pH. Two commercially available sodium bicarbonate preparations, 4% (wt/vol) and 8.4% (wt/vol), were compared and produced similar pH changes and precipitation behavior. The data obtained for pH and time to precipitation for local anesthetic solutions alkalinized with sodium bicarbonate may be useful for practical application in the clinical setting. PMID:2562097

  11. Reassimilation of ammonium in Lotus japonicus.

    PubMed

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

    2014-10-01

    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. PMID:24948681

  12. Ammonium nitrate: a promising rocket propellant oxidizer

    PubMed

    Oommen; Jain

    1999-06-30

    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. PMID:10370180

  13. Bicarbonate-based Integrated Carbon Capture and Algae Production System with alkalihalophilic cyanobacterium.

    PubMed

    Chi, Zhanyou; Xie, Yuxiao; Elloy, Farah; Zheng, Yubin; Hu, Yucai; Chen, Shulin

    2013-04-01

    An extremely alkalihalophilic cyanobacteria Euhalothece ZM001 was tested in the Bicarbonate-based Integrated Carbon Capture and Algae Production System (BICCAPS), which utilize bicarbonate as carbon source for algae culture and use the regenerated carbonate to absorb CO2. Culture conditions including temperature, inoculation rate, medium composition, pH, and light intensity were investigated. A final biomass concentration of 4.79 g/L was reached in tissue flask culture with 1.0 M NaHCO3/Na2CO3. The biomass productivity of 1.21 g/L/day was achieved under optimal conditions. When pH increased from 9.55 to 10.51, 0.256 M of inorganic carbon was consumed during the culture process. This indicated sufficient carbon can be supplied as bicarbonate to the culture. This study proved that a high biomass production rate can be achieved in a BICCAPS. This strategy can also lead to new design of photobioreactors that provides an alternative supply of CO2 to sparging. PMID:23455223

  14. Effect of calcium, bicarbonate, and albumin on capacitation-related events in equine sperm.

    PubMed

    Macías-García, B; González-Fernández, L; Loux, S C; Rocha, A M; Guimarães, T; Peña, F J; Varner, D D; Hinrichs, K

    2015-01-01

    Repeatable methods for IVF have not been established in the horse, reflecting the failure of standard capacitating media to induce changes required for fertilization capacity in equine sperm. One important step in capacitation is membrane cholesterol efflux, which in other species is triggered by cholesterol oxidation and is typically enhanced using albumin as a sterol acceptor. We incubated equine sperm in the presence of calcium, BSA, and bicarbonate, alone or in combination. Bicarbonate induced an increase in reactive oxygen species (ROS) that was abolished by the addition of calcium or BSA. Bicarbonate induced protein tyrosine phosphorylation (PY), even in the presence of calcium or BSA. Incubation at high pH enhanced PY but did not increase ROS production. Notably, no combination of these factors was associated with significant cholesterol efflux, as assessed by fluorescent quantitative cholesterol assay and confirmed by filipin staining. By contrast, sperm treated with methyl-?-cyclodextrin showed a significant reduction in cholesterol levels, but no significant increase in PY or ROS. Presence of BSA increased sperm binding to bovine zonae pellucidae in all three stallions. These results show that presence of serum albumin is not associated with a reduction in membrane cholesterol levels in equine sperm, highlighting the failure of equine sperm to exhibit core capacitation-related changes in a standard capacitating medium. These data indicate an atypical relationship among cholesterol efflux, ROS production, and PY in equine sperm. Our findings may help to elucidate factors affecting failure of equine IVF under standard conditions. PMID:25349439

  15. Pilot scale-SO{sub 2} control by dry sodium bicarbonate injection and an electrostatic precipitator

    SciTech Connect

    Pliat, M.J.; Wilder, J.M. [University of Washington, Seattle, WA (United States). Dept. of Civil & Environmental Engineering

    2007-10-15

    A 500 actual cubic feet gas per minute (acfm) pilot-scale SO{sub 2} control study was undertaken to investigate flue gas desulfurization (FGD) by dry sodium sorbents in 400{sup o}F (204.5{sup o}C) flue gases emitted from a coal fired boiler with flue gas concentrations between 350 and 2500 ppm SO{sub 2}. Powdered sodium alkaline reagents were injected into the hot flue gas downstream of the air preheater and the spent reagents were collected using an electrostatic precipitator. Three different sorbents were used: processed sodium bicarbonate of two particle sizes; solution mined sodium bicarbonate, and processed sodium sesquicarbonate. SO{sub 2} concentrations were measured upstream of the reagent injection, 25-ft (7.62 m) downstream of the injection point, and downstream of the electrostatic precipitator. SO{sub 2} collection efficiencies ranged from 40 to 80% using sodium bicarbonate stoichiometric ratios from 0.5 to 3.0. Much of the in-duct SO{sub 2} removal occurred during the first second of reagent reaction time, indicating that the sulfur dioxide-sodium reaction rates may be faster than have been measured for fixed bed measurements reported in the literature.

  16. Repeated High Intensity Bouts with Long Recovery: Are Bicarbonate or Carbohydrate Supplements an Option?

    PubMed Central

    Stöggl, Thomas; Torres-Peralta, Rafael; Cetin, Ebru

    2014-01-01

    The effects of varying recovery modes and the influence of preexercise sodium bicarbonate and carbohydrate ingestion on repeated high intensity performance, acid-base response, and recovery were analyzed in 12 well-trained males. They completed three repeated high intensity running bouts to exhaustion with intervening recovery periods of 25?min under the following conditions: sodium bicarbonate, active recovery (BIC); carbohydrate ingestion, active recovery (CHO); placebo ingestion, active recovery (ACTIVE); placebo ingestion, passive recovery (PASSIVE). Blood lactate (BLa), blood gases, heart rate, and time to exhaustion were collected. The three high intensity bouts had a duration of 138 ± 9, 124 ± 6, and 121 ± 6?s demonstrating a decrease from bout 1 to bout 3. Supplementation strategy had no effect on performance in the first bout, even with differences in pH and bicarbonate (HCO3?). Repeated sprint performance was not affected by supplementation strategy when compared to ACTIVE, while PASSIVE resulted in a more pronounced decrease in performance compared with all other interventions. BIC led to greater BLa, pH, and HCO3? values compared with all other interventions, while for PASSIVE the opposite was found. BLa recovery was lowest in PASSIVE; recovery in pH, and HCO3? was lower in PASSIVE and higher in BIC. PMID:25431775

  17. Evidence for a Detrimental Effect of Bicarbonate Therapy in Hypoxic Lactic Acidosis

    NASA Astrophysics Data System (ADS)

    Graf, Helmut; Leach, William; Arieff, Allen I.

    1985-02-01

    Lactic acidosis, a clinical syndrome caused by the accumulation of lactic acid, is characterized by lactate concentration in blood greater than 5 mM. Therapy usually consists of intravenous sodium bicarbonate (NaHCO3), but resultant mortality is greater than 60 percent. The metabolic and systemic effects of NaHCO3 therapy of hypoxic lactic acidosis in dogs were studied and compared to the effects of sodium chloride or no therapy. Sodium bicarbonate elevated blood lactate concentrations to a greater extent than did either sodium chloride or no treatment. Despite the infusion of NaHCO3, both arterial pH and bicarbonate concentration decreased by a similar amount in all three groups of dogs. Additional detrimental effects of NaHCO3 were observed on the cardiovascular system, including decreases in cardiac output and blood pressure that were not observed with either sodium chloride or no treatment. Thus there is evidence for a harmful effect of NaHCO3 in the treatment of hypoxic lactic acidosis.

  18. Loop diuretics reduce lithium reabsorption without affecting bicarbonate and phosphate reabsorption.

    PubMed

    Stokke, E S; Ostensen, J; Hartmann, A; Kiil, F

    1990-09-01

    The effects of the loop diuretics ethacrynic acid and bumetanide on lithium, bicarbonate and phosphate reabsorption were compared in 16 anaesthetized, normovolaemic dogs. In six dogs, ethacrynic acid (3 mg kg-1 body wt) significantly reduced absolute lithium reabsorption from 29.3 +/- 4.1 to 19.0 +/- 3.4 mumol min-1, fractional lithium reabsorption from 0.65 +/- 0.04 to 0.37 +/- 0.04 and fractional chloride reabsorption from 1.00 +/- 0.00 to 0.65 +/- 0.02. Bicarbonate and phosphate reabsorption did not decrease significantly. In six other dogs, bumetanide (30 micrograms kg-1 body wt) gave similar results. Absolute lithium reabsorption significantly decreased from 34.0 +/- 2.2 to 18.1 +/- 2.6 mumol min-1 and fractional lithium reabsorption decreased from 0.50 +/- 0.03 to 0.25 +/- 0.03. Fractional chloride reabsorption decreased from 0.98 +/- 0.00 to 0.61 +/- 0.05, whereas bicarbonate and phosphate reabsorption were not significantly altered. Thus, both loop diuretics greatly reduced lithium reabsorption. We propose that loop diuretics inhibit passive lithium reabsorption in the thick ascending limb of Henle's loop by reducing the lumen-positive electrical potential that drives passive cation transport. PMID:2125801

  19. Social buffering: relief from stress and anxiety

    PubMed Central

    Kikusui, Takefumi; Winslow, James T; Mori, Yuji

    2006-01-01

    Communication is essential to members of a society not only for the expression of personal information, but also for the protection from environmental threats. Highly social mammals have a distinct characteristic: when conspecific animals are together, they show a better recovery from experiences of distress. This phenomenon, termed ‘social buffering’, has been found in rodents, birds, non-human primates and also in humans. This paper reviews classical findings on social buffering and focuses, in particular, on social buffering effects in relation to neuroendocrine stress responses. The social cues that transmit social buffering signals, the neural mechanisms of social buffering and a partner's efficacy with respect to social buffering are also detailed. Social contact appears to have a very positive influence on the psychological and the physiological aspects of social animals, including human beings. Research leading towards further understanding of the mechanisms of social buffering could provide alternative medical treatments based on the natural, individual characteristics of social animals, which could improve the quality of life. PMID:17118934

  20. Effect of Feeding Sodium and Potassium Bicarbonate on Milk Fat, Rumen pH, and Volatile Fatty Acid Production1

    Microsoft Academic Search

    R. S. Emery; L. D. Brown

    1961-01-01

    SUM~M:ARY Sodium or potassium bicarbonates (1 lb\\/day) were added to the rations of cows fed grain to appetite and 2 lb. of long or pelleted hay. These bicarbonates prevented the decline in milk fat percentage frequently associated with such rations. The pH of the rumen contents was increased, but the molar proportion of the acids was not appreciably altered. The

  1. Influence of Dietary Sodium and Potassium Bicarbonate and Total Potassium on Heat-Stressed Lactating Dairy Cows1

    Microsoft Academic Search

    P. L. Schneider; D. K. Beede; C. J. Wilcox; R. J. Collier

    1984-01-01

    Objectives were to study effects of heat stress, 0 or .85% sodium bicarbonate, 0 or 1.0% potassium bicarbonate, and 1.0 or 1.5% total dietary potassium on production and physiological responses of dairy cows. Eighteen lactating Holsteins were assigned to shade (control) or no shade (heat stress) lots continuously for three consecutive 35-day periods and to different dietary treatments each period.

  2. Oral Sodium Bicarbonate for the Treatment of Metabolic Acidosis in Peritoneal Dialysis Patients: A Randomized Placebo-Control Trial

    Microsoft Academic Search

    CHEUK-CHUN SZETO; TERESA YUK-HWA WONG; KAI-MING CHOW; CHI-BON LEUNG; PHILIP KAM-TAO LI

    Acidosis causes malnutrition in peritoneal dialysis (PD) patients. The effect of oral bicarbonate in PD patients with Kt\\/V 2.1 has not been studied. We randomly assigned 60 PD patients with acidosis and Kt\\/V 2.1 to oral sodium bicarbonate (0.9 g thrice daily) or placebo. Patients were fol- lowed for 12 mo. We compared their nutritional status, includ- ing subjective global

  3. Ammonium removal from concentrated waste streams with the anaerobic ammonium oxidation (Anammox) process in different reactor configurations

    Microsoft Academic Search

    Marc Strous; Eric Van Gerven; Ping Zheng; J. Gijs Kuenen; Mike S. M. Jetten

    1997-01-01

    Many concentrated wastewater streams produced in food and agro-industry are treated using sludge digestion. The effluent from sludge digestors frequently contains ammonium in high concentrations (up to 2 kg m?3). This ammonium-rich effluent is usually treated by a normal wastewater treatment plant (WWTP). When ammonium removal from this concentrated stream is considered, steam stripping or a combination of two biological

  4. Augmented bicarbonate reabsorption by both the proximal and distal nephron maintains chloride-deplete metabolic alkalosis in rats.

    PubMed Central

    Wesson, D E

    1989-01-01

    Whether augmented bicarbonate reabsorption by renal tubular epithelium contributes to the maintenance of chloride-deplete metabolic alkalosis is not clear. This study used free-flow micropuncture to investigate bicarbonate reabsorption by surface nephron segments in a rat model of diuretic-induced alkalosis compared to control. The proximal and distal nephron of the alkalotic animals had higher values for both delivered load to and absolute reabsorption from these segments. The proximal tubules of alkalotic and control animals had similar values for the slopes of the linear regression of delivered load vs. reabsorption and for the bicarbonate tubular fluid to plasma (TF/P) ratio at the late proximal tubule. By contrast, the corresponding analysis for the distal segment of alkalotic animals revealed a greater slope (0.98 vs. 0.81, P less than 0.003) and a smaller bicarbonate TF/P ratio at the late distal tubule (0.10 vs. 0.16, P less than 0.006). The data indicate that augmented bicarbonate reabsorption by both the proximal and distal nephron contributes to maintaining the alkalosis of this model. The data suggest primary stimulation of bicarbonate reabsorption in the distal nephron and load-dependent reabsorption in the proximal tubule. PMID:2808701

  5. The stoichiometry of the electrogenic sodium bicarbonate cotransporter NBC1 is cell-type dependent

    PubMed Central

    Gross, E; Hawkins, K; Abuladze, N; Pushkin, A; Cotton, C U; Hopfer, U; Kurtz, I

    2001-01-01

    The pancreatic variant of the sodium bicarbonate cotransporter, pNBC1, mediates basolateral bicarbonate influx in the exocrine pancreas by coupling the transport of bicarbonate to that of sodium, with a 2 HCO3?:1 Na+ stoichiometry. The kidney variant, kNBC1, mediates basolateral bicarbonate efflux in the proximal tubule by coupling the transport of 3 HCO3? to 1 Na+. The molecular basis underlying the different stoichiometries is not known. pNBC1 and kNBC1 are 93 % identical to each other with 41 N-terminal amino acids of kNBC1 replaced by 85 distinct amino acids in pNBC1. In this study we tested the hypothesis that the differences in stoichiometry are related to the difference between the N-termini of the two proteins. Mouse renal proximal tubule and collecting duct cells, deficient in both pNBC1- and kNBC1-mediated electrogenic sodium bicarbonate cotransport function were transfected with either pNBC1 or kNBC1. Cells were grown on a permeable support to confluence, mounted in an Ussing chamber and permeabilized apically with amphotericin B. Current through the cotransporter was isolated as the difference current due to the reversible inhibitor dinitrostilbene disulfonate. The stoichiometry was calculated from the reversal potential by measuring the current-voltage relationships of the cotransporter at different Na+ concentration gradients. Our data indicate that both kNBC1 and pNBC1 can exhibit either a 2:1 or 3:1 stoichiometry depending on the cell type in which each is expressed. In proximal tubule cells, both pNBC1 and kNBC1 exhibit a 3 HCO3?:1 Na+ stoichiometry, whereas in collecting duct cells, they have a 2:1 stoichiometry. These data argue against the hypothesis that the stoichiometric differences are related to the difference between the N-termini of the two proteins. Moreover, the results suggest that as yet unidentified cellular factor(s) may modify the stoichiometry of these cotransporters. PMID:11251043

  6. The effect of drugs acting on cholinoceptors and mucosal chloride on luminal bicarbonate transport by rat caecum under in vitro conditions.

    PubMed Central

    Canfield, P.; Abdul-Ghaffar, T.

    1991-01-01

    1. The transport of HCO3- (Jsm) from a HCO3(-)-buffered serosal to an unbuffered mucosal saline solution has been studied in rat caecum in vitro. 2. Carbachol, bethanechol and acetylcholine (ACh) caused a concentration-dependent fall in Jsm with similar maximum effects. 1,1-Dimethyl-4-phenyl-piperazinium iodide (DMPP) also inhibited Jsm but the effect was less than with the other drugs. Maximum cholinoceptor inhibition was less than that obtained with anoxia. 3. Responses were blocked by atropine (10(-5) M) but hexamethonium (2 x 10(-4) M) significantly altered the response only to DMPP. 4. Physostigmine (10(-5) M) shifted the ACh response curve to the left but physostigmine itself caused inhibition of Jsm which was blocked by atropine. 5. Substitution of mucosal Cl- by NO3- reduced Jsm to a similar extent to maximum cholinoceptor effect and abolished responses to bethanecol. Anoxia further reduced Jsm in the presence of NO3-. 6. Mucosal SITS and DIDS (1 mM) reduced Jsm but this was less than the maximum inhibition seen with drugs acting on cholinoceptors or mucosal Cl- removal. Serosal DIDS caused a similar inhibition. 7. We conclude that cholinoceptor agonists inhibit but do not abolish luminal bicarbonate transport by an action on muscarinic receptors. PMID:1884114

  7. The Influence of Buffer Species and Strength on Diltiazem HC1 Release from Beads Coated with the Aqueous Cationic Polymer Dispersions, Eudragit RS, RL 30D

    Microsoft Academic Search

    Roland Bodmeier; Xiaodi Guo; Rafael E. Sarabia; Paul F. Skultety

    1996-01-01

    Purpose. Eudragit RL and RS 30D are pseudolatexes frequently used in the coating of solid dosage forms. They are based on cationic copolymers stabilized with quaternary ammonium groups (poly(ethylacrylate-methylmethacrylate-trimethylammonioethyl methacrylate chloride). A pH-independent drug release is expected because of the quaternary nature of the cationic groups. The objective was to explain a distinct “pH-dependent” drug release in various buffer media

  8. A MICROPROCESSOR ASCII CHARACTER BUFFERING SYSTEM

    EPA Science Inventory

    A microprocessor buffering system (MBS) was developed at the Environmental Monitoring and Support Laboratory -Cincinnati (EMSL-CI) to provide an efficient transfer for serial ASCII information between intelligent instrument systema and a Data General NOVA laboratory automation co...

  9. Buffer assignment algorithms for data driven architectures

    E-print Network

    Chatterjee, Mitrajit

    1994-01-01

    Data driven architectures designed to achieve high performance and throughput require the corresponding data flow graph to have no accumulation of data at its nodes and simultaneous arrival of all input data to a multi-input node. Buffers...

  10. Comparison of the Kinetic Rate Law Parameters for the Dissolution of Natural and Synthetic Autunite in the Presence of Aqueous Bicarbonate Ions

    SciTech Connect

    Gudavalli, Ravi; Katsenovich, Yelena; Wellman, Dawn M.; Idarraga, Melina; Lagos, Leonel; Tansel, Berrin

    2013-08-02

    Bicarbonate is one of the most significant components within the uranium geochemical cycle. In aqueous solutions, bicarbonate forms strong complexes with uranium. As such, aqueous bicarbonate may significantly increase the rate of uranium release from uranium minerals. Quantifying the relationship of aqueous bicarbonate concentration to the rate of uranium release during dissolution is critical to understanding the long-term fate of uranium within the environment. Single-pass flow-through (SPTF) experiments were conducted to estimate the rate of uranium release from Na meta-autunite as a function of bicarbonate (0.0005-0.003 M) under the pH range of 6-11 and a temperature range of 5-60oC. Consistent with the results of previous investigation, the rate of uranium release exhibited minimal dependency on temperature; but were strongly dependent on pH. Increasing aqueous bicarbonate concentrations afforded comparable increases in the rate of release of uranium. Most notably under low pH conditions the aqueous bicarbonate resulted in up to 370 fold increases in the rate of uranium release in relative to the rate of uranium release in the absence of bicarbonate. However, the effect of aqueous bicarbonate on the release of uranium was significantly less under higher pH conditions. It is postulated that at high pH values, surface sites are saturated with carbonate, thus the addition of more bicarbonate would have less effect on uranium release.

  11. ABS: Adaptive Buffer Sizing for Heterogeneous Networks

    Microsoft Academic Search

    Yueping Zhang; Dmitri Loguinov

    2008-01-01

    Abstract—Most existing criteria [3], [5], [9] for sizing router buffers rely on explicit formulation,of the relationship between buffer size and characteristics of Internet traffic. However, this is a non-trivial, if not impossible, task given that the number of flows, their individual RTTs, and congestion control methods, as well as flow responsiveness, are unknown. In this paper, we undertake,a completely,different approach,that

  12. Buffer layer for thin film structures

    DOEpatents

    Foltyn, Stephen R.; Jia, Quanxi; Arendt, Paul N.; Wang, Haiyan

    2006-10-31

    A composite structure including a base substrate and a layer of a mixture of strontium titanate and strontium ruthenate is provided. A superconducting article can include a composite structure including an outermost layer of magnesium oxide, a buffer layer of strontium titanate or a mixture of strontium titanate and strontium ruthenate and a top-layer of a superconducting material such as YBCO upon the buffer layer.

  13. Buffer layer for thin film structures

    DOEpatents

    Foltyn, Stephen R.; Jia, Quanxi; Arendt, Paul N.; Wang, Haiyan

    2010-06-15

    A composite structure including a base substrate and a layer of a mixture of strontium titanate and strontium ruthenate is provided. A superconducting article can include a composite structure including an outermost layer of magnesium oxide, a buffer layer of strontium titanate or a mixture of strontium titanate and strontium ruthenate and a top-layer of a superconducting material such as YBCO upon the buffer layer.

  14. Microbial ammonium cycling in the Mississippi River plume during

    E-print Network

    Jochem, Frank J.

    Microbial ammonium cycling in the Mississippi River plume during the drought spring of 2000 FRANK J of ammonium (NH4 + ) were studied along a salinity gradient (salinities 0.2­34.4) in the Mississippi River of Mexico are influenced by riverine freshwater inputs from the Mississippi River, which introduces

  15. Racer (Ammonium Nonanoate) weed control evaluation for onions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Racer has been labeled as a herbicide for food use and is currently under consideration as an organic herbicide for organically grown food crops. The main component (40%) of Racer is ammonium nonanoate (ammonium pelargonate), which occurs in nature and primarily formed from biodegradation of higher...

  16. Chitosan nanoparticles as a novel delivery system for ammonium glycyrrhizinate

    Microsoft Academic Search

    Yan Wu; Wuli Yang; Changchun Wang; Jianhua Hu; Shoukuan Fu

    2005-01-01

    The ammonium glycyrrhizinate-loaded chitosan nanoparticles were prepared by ionic gelation of chitosan with tripolyphos- phate anions (TPP). The particle size and zeta potential of nanoparticles were determined, respectively, by dynamic light scattering (DLS) and a zeta potential analyzer. The effects, including chitosan molecular weight, chitosan concentration, ammonium gly- cyrrhizinate concentration and polyethylene glycol (PEG) on the physicochemical properties of the

  17. AMMONIUM SULFATE AND BISULFATE FORMATION IN AIR PREHEATERS

    EPA Science Inventory

    The overall goal of this study was to investigate the problems which result from deposition of ammonium sulfates in an air preheater. More specifically, the study had three major objectives. The first was to determine the conditions under which ammonium sulfates are expected to f...

  18. Ammonium removal from wastewaters using natural New Zealand zeolites

    Microsoft Academic Search

    M. L. Nguyen; C. C. Tanner

    1998-01-01

    Ammoniacal nitrogen (ammonia and ammonium) in agricultural wastewaters can promote eutrophication of receiving waters and be potentially toxic to fish and other aquatic life. Zeolites, which are hydrated aluminum?silicate minerals, have an affinity for ammonium ions (NH4 ) and are, therefore, potentially useful in removing this contaminant from wastewaters. The major objectives of this study were to evaluate the capacity

  19. Buffer regulation of calcium puff sequences

    NASA Astrophysics Data System (ADS)

    Fraiman, Daniel; Ponce Dawson, Silvina

    2014-02-01

    Puffs are localized Ca2 + signals that arise in oocytes in response to inositol 1,4,5-trisphosphate (IP3). They are the result of the liberation of Ca2 + from the endoplasmic reticulum through the coordinated opening of IP3 receptor/channels clustered at a functional release site. The presence of buffers that trap Ca2 + provides a mechanism that enriches the spatio-temporal dynamics of cytosolic calcium. The expression of different types of buffers along the cell's life provides a tool with which Ca2 + signals and their responses can be modulated. In this paper we extend the stochastic model of a cluster of IP3R-Ca2 + channels introduced previously to elucidate the effect of buffers on sequences of puffs at the same release site. We obtain analytically the probability laws of the interpuff time and of the number of channels that participate of the puffs. Furthermore, we show that under typical experimental conditions the effect of buffers can be accounted for in terms of a simple inhibiting function. Hence, by exploring different inhibiting functions we are able to study the effect of a variety of buffers on the puff size and interpuff time distributions. We find the somewhat counter-intuitive result that the addition of a fast Ca2 + buffer can increase the average number of channels that participate of a puff.

  20. /GaAs (001) Metamorphic Buffer Layers

    NASA Astrophysics Data System (ADS)

    Kujofsa, T.; Ayers, J. E.

    2014-08-01

    The design of metamorphic buffer layers for semiconductor devices with reduced defect densities requires control of lattice relaxation and dislocation dynamics. Graded layers are beneficial for the design of these buffers because they reduce the threading dislocation density by (1) allowing the distribution of the misfit dislocations throughout the buffer layer therefore reducing pinning interactions, and (2) enhancing mobility from the high built-in surface strain which helps to sweep out threading arms. In this work, we considered heterostructures involving a linearly-graded (type A) or step-graded (type B) buffer grown on a GaAs (001) substrate. For each structure type, we studied the equilibrium configuration and the kinetically-limited lattice relaxation and non-equilibrium threading dislocations by utilizing a dislocation dynamics model. In this work, we have also considered heterostructures involving a constant composition ZnS y Se1- y device layer grown on top of a GaAs (001) substrate with an intermediate buffer layer of linearly-graded (type C) or step-graded (type D) ZnS y Se1- y . For each structure type, we studied the requirements on the thickness and compositional profile in the buffer layer for the elimination of all mobile threading dislocations from the device layer by the dislocation compensation mechanism.

  1. Buffer regulation of calcium puff sequences.

    PubMed

    Fraiman, Daniel; Dawson, Silvina Ponce

    2014-02-01

    Puffs are localized Ca(2 +) signals that arise in oocytes in response to inositol 1,4,5-trisphosphate (IP3). They are the result of the liberation of Ca(2 +) from the endoplasmic reticulum through the coordinated opening of IP3 receptor/channels clustered at a functional release site. The presence of buffers that trap Ca(2 +) provides a mechanism that enriches the spatio-temporal dynamics of cytosolic calcium. The expression of different types of buffers along the cell's life provides a tool with which Ca(2 +) signals and their responses can be modulated. In this paper we extend the stochastic model of a cluster of IP3R-Ca(2 +) channels introduced previously to elucidate the effect of buffers on sequences of puffs at the same release site. We obtain analytically the probability laws of the interpuff time and of the number of channels that participate of the puffs. Furthermore, we show that under typical experimental conditions the effect of buffers can be accounted for in terms of a simple inhibiting function. Hence, by exploring different inhibiting functions we are able to study the effect of a variety of buffers on the puff size and interpuff time distributions. We find the somewhat counter-intuitive result that the addition of a fast Ca(2 +) buffer can increase the average number of channels that participate of a puff. PMID:24476691

  2. Role of the buffer solution in the chemical deposition of CdS films for CIGS solar cell applications

    NASA Astrophysics Data System (ADS)

    Lee, Sooho; Kim, Donguk; Baek, Dohyun; Hong, Byoungyou; Yi, Junsin; Lee, Jaehyeong; Park, Yong Seob; Choi, Wonseok

    2014-05-01

    In this work, the effects of NH4Ac on the structural and the electro-optical properties of CdS films were investigated. CdS thin films were deposited on soda-lime glass and indium-tin-oxide (ITO) coated glass from a chemical bath containing 0.025 M cadmium acetate, 0 M ~ 0.2 M ammonium acetate, 0.5 M thiourea, and ammonia. Cadmium acetate was the cadmium source, ammonium acetate served as a buffer, ammonia was the complexing agent, and thiourea was the source of sulfur. A commonl- available chemical bath deposition system was successfully modified to obtain precise control over the pH of the solution at 75 °C during the deposition. Chemically deposited CdS films were studied by using field-emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), optical transmittance, and electrical resistivity measurements.

  3. Low noise buffer amplifiers and buffered phase comparators for precise time and frequency measurement and distribution

    NASA Technical Reports Server (NTRS)

    Eichinger, R. A.; Dachel, P.; Miller, W. H.; Ingold, J. S.

    1982-01-01

    Extremely low noise, high performance, wideband buffer amplifiers and buffered phase comparators were developed. These buffer amplifiers are designed to distribute reference frequencies from 30 KHz to 45 MHz from a hydrogen maser without degrading the hydrogen maser's performance. The buffered phase comparators are designed to intercompare the phase of state of the art hydrogen masers without adding any significant measurement system noise. These devices have a 27 femtosecond phase stability floor and are stable to better than one picosecond for long periods of time. Their temperature coefficient is less than one picosecond per degree C, and they have shown virtually no voltage coefficients.

  4. Ammonium Metabolism Enzymes Aid Helicobacter pylori Acid Resistance

    PubMed Central

    Miller, Erica F.

    2014-01-01

    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) the exit of protonated ammonium outward via the UreI permease, which was shown to facilitate diffusion of both urea and ammonium, and/or (ii) the assimilation of this ammonium, which is supported by evidence that H. pylori assimilates urea nitrogen into its amino acid pools. We investigated the second hypothesis by constructing strains with altered expression of the ammonium-assimilating enzymes glutamine synthetase (GS) and glutamate dehydrogenase (GDH) and the ammonium-evolving periplasmic enzymes glutaminase (Ggt) and asparaginase (AsnB). H. pylori strains expressing elevated levels of either GS or GDH are more acid tolerant than the wild type, exhibit enhanced ammonium production, and are able to alkalize the medium faster than the wild type. Strains lacking the genes for either Ggt or AsnB are acid sensitive, have 8-fold-lower urea-dependent ammonium production, and are more acid sensitive than the parent. Additionally, we found that purified H. pylori GS produces glutamine in the presence of Mg2+ at a rate similar to that of unadenylated Escherichia coli GS. These data reveal that all four enzymes contribute to whole-cell acid resistance in H. pylori and are likely important for assimilation and/or efflux of urea-derived ammonium. PMID:24936052

  5. Hybrid organic-inorganic crystals based on ammonium dihydrogen phosphate and ammonium salicylate

    NASA Astrophysics Data System (ADS)

    Voronov, A. P.; Salo, V. I.; Puzikov, V. M.; Babenko, G. N.; Roshal, A. D.; Tkachenko, V. F.

    2011-11-01

    ADP-NH 4Sal hybrid crystals are grown from aqueous solutions. The influence of the acidity of the mixed solution on the conditions of co-crystallization of the components is studied. The spectral and scintillation characteristics are determined. Co-crystallization of ammonium salicylate (NH 4Sal) and ammonium dihydrogen phosphate (ADP, NH 4H 2PO 4) is shown to be feasible, the structure of the doping addition being defined by the solution ??. In basic and weak acidic media the hybrid crystals ADP:NH 4Sal are formed in which salicylate anions are located in the interplanar space between the {110}-type planes in the lattice of ADP. The luminescence spectra contain an emission band maximum with ? max=360 nm. In acidic solutions there are ADP:HSal crystals in which salicylic acid molecules captured by the growth macrosteps are located in the interplanar space of the prismatic {100} and pyramidal {101} growth sectors. The luminescence band undergoes bathochromic shift to ?max=400 nm. The sensitivity of ADP:NH 4Sal scintillation crystals to fast neutrons depends on the concentration of ammonium salicylate in ADP matrix. The highest neutron sensitivity is characteristic of the co-doped ADP:NH 4Sal/Tl scintillation crystals.

  6. 78 FR 35258 - Solid Agricultural Grade Ammonium Nitrate from Ukraine: Continuation of Antidumping Duty Order

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-12

    ...Trade Administration [A-823-810] Solid Agricultural Grade Ammonium Nitrate from...of the antidumping duty order \\1\\ on solid agricultural grade ammonium nitrate from...1\\ See Antidumping Duty Order: Solid Agricultural Grade Ammonium Nitrate...

  7. 77 FR 65532 - Solid Fertilizer Grade Ammonium Nitrate From the Russian Federation: Notice of Rescission of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-29

    ...Fertilizer Grade Ammonium Nitrate From the Russian Federation: Notice of Rescission of Antidumping...nitrate (ammonium nitrate) from the Russian Federation (Russia) for the period of...Nitrate (Ammonium Nitrate) from the Russian Federation (Russia): Data Query...

  8. 76 FR 49449 - Continuation of Antidumping Duty Order on Solid Fertilizer Grade Ammonium Nitrate From the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-10

    ...Fertilizer Grade Ammonium Nitrate From the Russian Federation AGENCY: Import Administration...ammonium nitrate'') from the Russian Federation (``Russia'') would likely...Fertilizer Grade Ammonium Nitrate From the Russian Federation and Notice of Antidumping...

  9. 76 FR 39847 - Solid Fertilizer Grade Ammonium Nitrate From the Russian Federation; Final Results of the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-07

    ...Fertilizer Grade Ammonium Nitrate From the Russian Federation; Final Results of the Expedited...ammonium nitrate'') from the Russian Federation (``Russia'').\\1...Fertilizer Grade Ammonium Nitrate From the Russian Federation, 64 FR 45236 (August...

  10. 40 CFR 415.240 - Applicability; description of the ammonium chloride production subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...CATEGORY Ammonium Chloride Production Subcategory § 415.240...description of the ammonium chloride production subcategory. The provisions...discharges resulting from the production of ammonium chloride by the...of anhydrous ammonia with hydrogen chloride gas and by the...

  11. 40 CFR 721.10170 - Polyoxyethylene polyalkylarylphenylether sulfate ammonium salt (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...polyalkylarylphenylether sulfate ammonium salt (generic). 721.10170 Section 721...polyalkylarylphenylether sulfate ammonium salt (generic). (a) Chemical substance...polyalkylarylphenylether sulfate ammonium salt (PMN P-03-197) is subject to...

  12. 40 CFR 721.10170 - Polyoxyethylene polyalkylarylphenylether sulfate ammonium salt (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...polyalkylarylphenylether sulfate ammonium salt (generic). 721.10170 Section 721...polyalkylarylphenylether sulfate ammonium salt (generic). (a) Chemical substance...polyalkylarylphenylether sulfate ammonium salt (PMN P-03-197) is subject to...

  13. 40 CFR 721.9075 - Quaternary ammonium salt of fluorinated alkylaryl amide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 false Quaternary ammonium salt of fluorinated alkylaryl amide. 721...Substances § 721.9075 Quaternary ammonium salt of fluorinated alkylaryl amide. ...identified generically as quaternary ammonium salt of fluorinated alkylaryl amide...

  14. 40 CFR 721.10170 - Polyoxyethylene polyalkylarylphenylether sulfate ammonium salt (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...polyalkylarylphenylether sulfate ammonium salt (generic). 721.10170 Section 721...polyalkylarylphenylether sulfate ammonium salt (generic). (a) Chemical substance...polyalkylarylphenylether sulfate ammonium salt (PMN P-03-197) is subject to...

  15. 40 CFR 721.10443 - Ethoxylated alkylphenol sulfate, ammonium salt (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Ethoxylated alkylphenol sulfate, ammonium salt (generic). 721.10443 Section 721...Ethoxylated alkylphenol sulfate, ammonium salt (generic). (a) Chemical substance...ethoxylated alkylphenol sulfate, ammonium salt (PMN P-01-470) is subject to...

  16. 40 CFR 721.9075 - Quaternary ammonium salt of fluorinated alkylaryl amide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 false Quaternary ammonium salt of fluorinated alkylaryl amide. 721...Substances § 721.9075 Quaternary ammonium salt of fluorinated alkylaryl amide. ...identified generically as quaternary ammonium salt of fluorinated alkylaryl amide...

  17. 40 CFR 418.40 - Applicability; description of the ammonium nitrate subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...description of the ammonium nitrate subcategory. The provisions...the manufacture of ammonium nitrate. Discharges attributable...battery limits of the ammonium nitrate manufacturing operations...306(b), Federal Water Pollution Control Act, as...

  18. Biological treatment of ammonium-rich wastewater by partial nitritation and subsequent anaerobic ammonium oxidation (anammox) in a pilot plant

    Microsoft Academic Search

    Christian Fux; Marc Boehler; Philipp Huber; Irene Brunner; Hansruedi Siegrist

    2002-01-01

    In wastewater treatment plants with anaerobic sludge digestion, 15–20% of the nitrogen load is recirculated to the main stream with the return liquors from dewatering. Separate treatment of this ammonium-rich digester supernatant would significantly reduce the nitrogen load of the activated sludge system. Some years ago, a novel biological process was discovered in which ammonium is converted to nitrogen gas

  19. PULMONARY FUNCTION IN ELASTASE-TREATED GUINEA PIGS AND RATS EXPOSED TO AMMONIUM SULFATE OR AMMONIUM NITRATE AEROSOLS

    EPA Science Inventory

    Three weeks following intratracheal instillations of elastase dissolved in saline, or saline alone, guinea pigs and rats were exposed for 5 or 20 days, 6 hr/day, 5 days/week to filtered room air, 1 mg/cu.m. ammonium sulfate ((NH4)2SO4) or 1 mg/cu.m. ammonium nitrate (NH4NO3) aero...

  20. Quantification of Kinetic Rate Law Parameters of Uranium Release from Sodium Autunite as a Function of Aqueous Bicarbonate Concentrations

    SciTech Connect

    Gudavalli, Ravi; Katsenovich, Yelena; Wellman, Dawn M.; Lagos, Leonel; Tansel, Berrin

    2013-09-05

    ABSTRACT: Hydrogen carbonate is one of the most significant components within the uranium geochemical cycle. In aqueous solutions, hydrogen carbonate forms strong complexes with uranium. As such, aqueous bicarbonate may significantly increase the rate of uranium release from uranium minerals. Quantifying the relationship of aqueous hydrogen carbonate solutions to the rate of uranium release during dissolution is critical to understanding the long-term fate of uranium within the environment. Single-pass flow-through (SPTF) experiments were conducted to estimate the rate of uranium release from Na meta-autunite as a function of bicarbonate solutions (0.0005-0.003 M) under the pH range of 6-11 and temperatures of 5-60oC. Consistent with the results of previous investigation, the rate of uranium release from sodium autunite exhibited minimal dependency on temperature; but were strongly dependent on pH and increasing concentrations of bicarbonate solutions. Most notably at pH 7, the rate of uranium release exhibited 370 fold increases relative to the rate of uranium release in the absence of bicarbonate. However, the effect of increasing concentrations of bicarbonate solutions on the release of uranium was significantly less under higher pH conditions. It is postulated that at high pH values, surface sites are saturated with carbonate, thus the addition of more bicarbonate would have less effect on uranium release. Results indicate the activation energies were unaffected by temperature and bicarbonate concentration variations, but were strongly dependent on pH conditions. As pH increased from 6 to 11, activation energy values were observed to decrease from 29.94 kJ mol-1 to 13.07 kJ mol-1. The calculated activation energies suggest a surface controlled dissolution mechanism.

  1. Infusion of sodium bicarbonate in experimentally induced metabolic acidosis does not provoke cerebrospinal fluid (CSF) acidosis in calves.

    PubMed

    Abeysekara, Saman; Zello, Gordon A; Lohmann, Katharina L; Alcorn, Jane; Hamilton, Don L; Naylor, Jonathan M

    2012-01-01

    In a crossover study, 5 calves were made acidotic by intermittent intravenous infusion of isotonic hydrochloric acid (HCl) over approximately 24 h. This was followed by rapid (4 h) or slow (24 h) correction of blood pH with isotonic sodium bicarbonate (NaHCO(3)) to determine if rapid correction of acidemia produced paradoxical cerebrospinal fluid (CSF) acidosis. Infusion of HCl produced a marked metabolic acidosis with respiratory compensation. Venous blood pH (mean ± S(x)) was 7.362 ± 0.021 and 7.116 ± 0.032, partial pressure of carbon dioxide (Pco(2), torr) 48.8 ± 1.3 and 34.8 ± 1.4, and bicarbonate (mmol/L), 27.2 ± 1.27 and 11 ± 0.96; CSF pH was 7.344 ± 0.031 and 7.240 ± 0.039, Pco(2) 42.8 ± 2.9 and 34.5 ± 1.4, and bicarbonate 23.5 ± 0.91 and 14.2 ± 1.09 for the period before the infusion of hydrochloric acid and immediately before the start of sodium bicarbonate correction, respectively. In calves treated with rapid infusion of sodium bicarbonate, correction of venous acidemia was significantly more rapid and increases in Pco(2) and bicarbonate in CSF were also more rapid. However, there was no significant difference in CSF pH. After 4 h of correction, CSF pH was 7.238 ± 0.040 and 7.256 ± 0.050, Pco(2) 44.4 ± 2.2 and 34.2 ± 2.1, and bicarbonate 17.8 ± 1.02 and 14.6 ± 1.4 for rapid and slow correction, respectively. Under the conditions of this experiment, rapid correction of acidemia did not provoke paradoxical CSF acidosis. PMID:22754090

  2. Bicarbonate Test

    MedlinePLUS

    ... identify or monitor an electrolyte imbalance or acid-base (pH) imbalance When to Get Tested? During a ... the body to help maintain the body's acid-base balance (pH) and secondarily to work with sodium , ...

  3. Effect of carbohydrate or sodium bicarbonate ingestion on performance during a validated basketball simulation test.

    PubMed

    Afman, Gregg; Garside, Richard M; Dinan, Neal; Gant, Nicholas; Betts, James A; Williams, Clyde

    2014-12-01

    Current recommendations for nutritional interventions in basketball are largely extrapolated from laboratory-based studies that are not sport-specific. We therefore adapted and validated a basketball simulation test relative to competitive basketball games using well-trained basketball players (n = 10), then employed this test to evaluate the effects of two common preexercise nutritional interventions on basketball-specific physical and skilled performance. Specifically, in a randomized and counterbalanced order, participants ingested solutions providing either 75 g carbohydrate (sucrose) 45 min before exercise (Study A; n = 10) or 2 × 0.2 g · kg(-1) sodium bicarbonate (NaHCO3) 90 and 20 min before exercise (Study B; n = 7), each relative to appropriate placebos (H2O and 2 × 0.14 g · kg(-1) NaCl, respectively). Heart rate, sweat rate, pedometer count, and perceived exertion did not systematically differ between the 60-min basketball simulation test and competitive basketball, with a strong positive correlation in heart rate response (r = .9, p < .001). Preexercise carbohydrate ingestion resulted in marked hypoglycemia (< 3.5 mmol · l(-1)) throughout the first quarter, coincident with impaired sprinting (+0.08 ± 0.05 second; p = .01) and layup shooting performance (8.5/11 versus 10.3/11 baskets; p < .01). However, ingestion of either carbohydrate or sodium bicarbonate before exercise offset fatigue such that sprinting performance was maintained into the final quarter relative to placebo (Study A: -0.07 ± 0.04 second; p < .01 and Study B: -0.08 ± 0.05 second; p = .02), although neither translated into improved skilled (layup shooting) performance. This basketball simulation test provides a valid reflection of physiological demands in competitive basketball and is sufficiently sensitive to detect meaningful changes in physical and skilled performance. While there are benefits of preexercise carbohydrate or sodium bicarbonate ingestion, these should be balanced against potential negative side effects. PMID:24901305

  4. Effect of bicarbonate supplementation on renal function and nutritional indices in predialysis advanced chronic kidney disease.

    PubMed

    Jeong, Jiwon; Kwon, Soon Kil; Kim, Hye-Young

    2014-12-01

    Current practice guidelines recommend alkali therapy in patients with chronic kidney disease (CKD) and metabolic acidosis to prevent complications. This study aims to investigate the effect of oral sodium bicarbonate supplementation on the progression of renal function and nutritional indices in patients with predialysis advanced CKD. Forty patients with predialysis stage 5 CKD(estimated glomerular filtration rate, eGFR <15mL/min per 1.73m(2)) and 40 patients with stage 4 CKD (eGFR 15 to 30mL/min per 1.73m(2)) who had a total CO2 less than 22mEq/L were assigned into the bicarbonate treatment group or control group for 12 months. In stage 4 CKD, there were significant differences in the changes of eGFR during the study between the treatment group and the control group (-2.30±4.49 versus -6.58±6.32mL/min/1.73m(2), p<0.05). However, in stage 5 CKD, there were no significant differences in the change of eGFR during the study between the two groups (-2.10±2.06 versus -3.23±1.95mL/min/1.73 m(2)).There were no significant differences in the changes of nutritional indices such as albumin, prealbumin, transferrin, total lymphocyte count (TLC), and Ondodera's prognostic nutritional index (OPNI) during the study between the two groups. In stage 5 CKD, there were significant differences in the changes of TLC and OPNI between the two groups. In conclusion, our results demonstrate that bicarbonate supplementation slows the rate of decline of renal function in stage 4 CKD and improves nutritional indices in stage 5 CKD. Alkali therapy in advanced CKD may have beneficial effect on renal function and malnutrition. PMID:25606047

  5. IL-17A Induces Pendrin Expression and Chloride-Bicarbonate Exchange in Human Bronchial Epithelial Cells

    PubMed Central

    Adams, Kelly M.; Abraham, Valsamma; Spielman, Daniel; Kolls, Jay K.; Rubenstein, Ronald C.; Conner, Gregory E.; Cohen, Noam A.; Kreindler, James L.

    2014-01-01

    The epithelium plays an active role in the response to inhaled pathogens in part by responding to signals from the immune system. Epithelial responses may include changes in chemokine expression, increased mucin production and antimicrobial peptide secretion, and changes in ion transport. We previously demonstrated that interleukin-17A (IL-17A), which is critical for lung host defense against extracellular bacteria, significantly raised airway surface pH in vitro, a finding that is common to a number of inflammatory diseases. Using microarray analysis of normal human bronchial epithelial (HBE) cells treated with IL-17A, we identified the electroneutral chloride-bicarbonate exchanger Pendrin (SLC26A4) as a potential mediator of this effect. These data were verified by real-time, quantitative PCR that demonstrated a time-dependent increase in Pendrin mRNA expression in HBE cells treated with IL-17A up to 48 h. Using immunoblotting and immunofluorescence, we confirmed that Pendrin protein expression is increased in IL-17 treated HBE cells and that it is primarily localized to the mucosal surface of the cells. Functional studies using live-cell fluorescence to measure intracellular pH demonstrated that IL-17A induced chloride-bicarbonate exchange in HBE cells that was not present in the absence of IL-17A. Furthermore, HBE cells treated with short interfering RNA against Pendrin showed substantially reduced chloride-bicarbonate exchange. These data suggest that Pendrin is part of IL-17A-dependent epithelial changes and that Pendrin may therefore be a therapeutic target in IL-17A-dependent lung disease. PMID:25141009

  6. Effect of Bicarbonate Supplementation on Renal Function and Nutritional Indices in Predialysis Advanced Chronic Kidney Disease

    PubMed Central

    Jeong, Jiwon; Kwon, Soon Kil

    2014-01-01

    Current practice guidelines recommend alkali therapy in patients with chronic kidney disease (CKD) and metabolic acidosis to prevent complications. This study aims to investigate the effect of oral sodium bicarbonate supplementation on the progression of renal function and nutritional indices in patients with predialysis advanced CKD. Forty patients with predialysis stage 5 CKD(estimated glomerular filtration rate, eGFR <15mL/min per 1.73m2) and 40 patients with stage 4 CKD (eGFR 15 to 30mL/min per 1.73m2) who had a total CO2 less than 22mEq/L were assigned into the bicarbonate treatment group or control group for 12 months. In stage 4 CKD, there were significant differences in the changes of eGFR during the study between the treatment group and the control group (-2.30±4.49 versus -6.58±6.32mL/min/1.73m2, p<0.05). However, in stage 5 CKD, there were no significant differences in the change of eGFR during the study between the two groups (-2.10±2.06 versus -3.23±1.95mL/min/1.73 m2).There were no significant differences in the changes of nutritional indices such as albumin, prealbumin, transferrin, total lymphocyte count (TLC), and Ondodera's prognostic nutritional index (OPNI) during the study between the two groups. In stage 5 CKD, there were significant differences in the changes of TLC and OPNI between the two groups. In conclusion, our results demonstrate that bicarbonate supplementation slows the rate of decline of renal function in stage 4 CKD and improves nutritional indices in stage 5 CKD. Alkali therapy in advanced CKD may have beneficial effect on renal function and malnutrition. PMID:25606047

  7. Intraoral evaluation of mineralization of cosmetic defects by a toothpaste containing calcium, fluoride, and sodium bicarbonate.

    PubMed

    Litkowski, Leonard J; Quinlan, Kathleen B; Ross, David R; Ghassemi, Annahita; Winston, Anthony; Charig, Andrew; Flickinger, Mark; Vorwerk, Linda

    2004-09-01

    New dual-phase fluoride toothpastes that contain soluble calcium, phosphate, and baking soda have recently been introduced into the market. These toothpastes are designed to fill in small surface defects in tooth enamel and thereby enhance tooth esthetics such as gloss. This two-part study was designed to assess these superficial mineralizing effects from using one of these products compared with an experimental calcium-containing, bicarbonate-free formulation and a conventional fluoride toothpaste using an intraoral model. Enamel specimens with 4 types of defects were mounted into an intraoral appliance and placed in the mouths of volunteers for 1 month. The four types of defects were whitening toothpaste abrasion, coarse abrasion, natural dimpling, and acid etching. Before and after intraoral exposure, scanning electron microscope photographs of the specimens were made. The surface microhardness of the acid-etched specimens also was determined. The volunteers brushed their specimens twice daily with one of three randomly assigned toothpastes. The toothpastes were a two-phase, calcium-containing, bicarbonate-based toothpaste; an experimental, two-phase, calcium-containing, bicarbonate-free toothpaste; and a conventional toothpaste. Only the calcium-containing toothpastes showed unequivocal signs of mineral deposition into surface defects, leading to smoothing of the enamel. All three products significantly increased the hardness of the etched enamel, presumably because of fluoride. However, only the two calcium-containing toothpastes gave significantly greater hardness increases than the conventional toothpaste; the specimens treated with a conventional toothpaste were indistinguishable from those treated with saliva. PMID:15645904

  8. Serum bicarbonate may independently predict acute kidney injury in critically ill patients: An observational study

    PubMed Central

    Gujadhur, Anuksha; Tiruvoipati, Ravindranath; Cole, Elizabeth; Malouf, Saada; Ansari, Erum Sahid; Wong, Kim

    2015-01-01

    AIM: To explore whether serum bicarbonate at admission to intensive care unit (ICU) predicted development of acute kidney injury (AKI). METHODS: We studied all patients admitted to our ICU over a 2 year period (February 2010 to 2012). The ICU has a case mix of medical and surgical patients excluding cardiac surgical, trauma and neurosurgical patients. We analysed 2035 consecutive patients admitted to ICU during the study period. Data were collected by two investigators independently and in duplicate using a standardised spread sheet to ensure accuracy. Ambiguous data were checked for accuracy where indicated. AKI was defined using the Kidney Disease Improving Global Outcomes criteria. Patients were divided into two groups; patients who developed AKI or those who did not, in order to compare the baseline characteristics, and laboratory and physiologic data of the two cohorts. Regression analysis was used to identify if serum bicarbonate on admission predicted the development of AKI. RESULTS: Of 2036 patients 152 (7.5%) were excluded due to missing data. AKI developed in 43.1% of the patients. The AKI group, compared to the non-AKI group, was sicker based on their lower systolic, diastolic and mean arterial pressures and a higher acute physiology and chronic health evaluation (APACHE) III and SAPS II scores. Moreover, patients who developed AKI had more co-morbidities and a higher proportion of patients who developed AKI required mechanical ventilation. The multi-regression analysis of independent variables showed that serum bicarbonate on admission (OR = 0.821; 95%CI: 0.796-0.846; P < 0.0001), APACHE III (OR = 1.011; 95%CI: 1.007-1.015; P < 0.0001), age (OR = 1.016; 95%CI: 1.008-1.024; P < 0.0001) and presence of sepsis at ICU admission (OR = 2.819; 95%CI: 2.122-23.744; P = 0.004) were each significant independent predictors of AKI. The area under the ROC curve was 0.8 (95%CI: 0.78-0.83), thereby demonstrating that the predictive model has relatively good discriminating power for predicting AKI. CONCLUSION: Serum bicarbonate on admission may independently be used to make a diagnosis of AKI. PMID:25685725

  9. Buffer Allocation Approaches for Virtual Channel Flow Control

    Microsoft Academic Search

    Neeraj Parik; Ozen Deniz; Paul Kim; Zheng Li

    Buffers are one of the major resources used by the routers in virtual channel flow control. It is reported that they consume 60% of routers' power and silicon (5). Architects of interconnection networks must use the buffers efficiently while assigning buffers to VCs from the fixed budget. This paper analyzes various buffer allocation approaches. All these approaches have constraint on

  10. Population of Nitrifying Bacteria and Nitrification in Ammonium Saturated Clinoptilolite

    NASA Technical Reports Server (NTRS)

    McGilloway, R. L.; Weaver, R. W.; Ming, Douglas W.; Gruener, J.

    1999-01-01

    As humans begin to spend longer periods of time in space, plants will be incorporated into life support systems. Ammonium saturated clinoptilolite is one plant growth substrate but a balance between ammonium and nitrate is needed. A laboratory study was conducted to determine effects of nitrifying bacteria on ammonium concentrations and kinetics of nitrification. Columns containing clinoptilolite substrate amended with nitrifying bacteria obtained from soil enrichment were analyzed weekly for a 90 day period. The enrichment culture initially contained 1 x 10(exp 5) ammonium oxidizing bacteria and 1 x 10(exp 2) nitrite oxidizing bacteria per gram of substrate. Populations of ammonium oxidizing bacteria increased to 1 x 10(exp 6) and nitrite oxidizing bacteria increased to 1 x 10(exp 3) per gram of substrate. The nitrification rate was approximately 0.25mg NO3(-)-N/kg.hr. Experiments were also conducted to enumerate nitrifying bacteria in a clinoptilolite substrate used to grow wheat (Triticum aestivum L.). Seventy days following the initial inoculation with an unknown number of commercial nitrifying bacteria, 1 x 10(exp 5) ammonium oxidizing bacteria per gram of substrate were present. The number of nitrite oxidizing bacteria was between 1 x 10(exp 3) to 10(exp 4) per gram of substrate as measured by the most probable number method. Nitrification rates were approximately 0.20mg NO3(-)-N/kg.hr. Clinoptilolite readily exchanged sufficient concentrations of ammonium to support nitrifying bacteria and they survived well in this medium.

  11. Undergraduate Chemistry Students' Perceptions of and Misconceptions about Buffers and Buffer Problems

    ERIC Educational Resources Information Center

    Orgill, MaryKay; Sutherland, Aynsley

    2008-01-01

    Both upper- and lower-level chemistry students struggle with understanding the concept of buffers and with solving corresponding buffer problems. While it might be reasonable to expect general chemistry students to struggle with this abstract concept, it is surprising that upper-level students in analytical chemistry and biochemistry continue to…

  12. Sample Questions (1) Phosphate buffered saline (PBS) is a buffer solution commonly used in biological research.

    E-print Network

    California at San Diego, University of

    Sample Questions (1) Phosphate buffered saline (PBS) is a buffer solution commonly used in biological research. It is a water-based salt solution containing sodium phosphate, sodium chloride and, in some formulations, potassium chloride and potassium phosphate. The osmolarity and ion concentrations

  13. 14C Fixation by Leaves and Leaf Cell Protoplasts of the Submerged Aquatic Angiosperm Potamogeton lucens: Carbon Dioxide or Bicarbonate? 1

    PubMed Central

    Staal, Marten; Elzenga, J. Theo M.; Prins, Hidde B. A.

    1989-01-01

    Protoplasts were isolated from leaves of the aquatic angiosperm Potamogeton lucens L. The leaves utilize bicarbonate as a carbon source for photosynthesis, and show polarity; that is, acidification of the periplasmic space of the lower, and alkalinization of the space near the upper leaf side. At present there are two models under consideration for this photosynthetic bicarbonate utilization process: conversion of bicarbonate into free carbon dioxide as a result of acidification and, second, a bicarbonate-proton symport across the plasma membrane. Carbon fixation of protoplasts was studied at different pH values and compared with that in leaf strips. Using the isotopic disequilibrium technique, it was established that carbon dioxide and not bicarbonate was the form in which DIC actually crossed the plasma membrane. It is concluded that there is probably no true bicarbonate transport system at the plasma membrane of these cells and that bicarbonate utilization in this species apparently rests on the conversion of bicarbonate into carbon dioxide. Experiments with acetazolamide, an inhibitor of periplasmic carbonic anhydrase, and direct measurements of carbonic anhydrase activity in intact leaves indicate that in this species the role of this enzyme for periplasmic conversion of bicarbonate into carbon dioxide is insignificant. PMID:16666848

  14. [Reasons of high concentration ammonium in Yellow River, China].

    PubMed

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

    2007-07-01

    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. PMID:17891948

  15. The effect of buffer species on hydration and mechanical properties of polymeric films prepared from aqueous colloidal cationic polymer dispersions

    SciTech Connect

    Guo, X.D.; Bodmeier, R. [Univ. of Texas, Austin, TX (United States); Sarabia, R.; Skultety, P. [Marion Merrell Dow Inc., Kansas City, MO (United States)

    1993-12-31

    Aqueous colloidal acrylic polymer dispersions have been used to formulate oral controlled drug delivery systems in the form of coated solid dosage forms. The hydration and mechanical properties of polymeric films prepared from Eudragit RS 30D (poly(ethylacrylate-methylmethacrylate-trimethylammonia ethyl methacrylate chloride) copolymers with ratios of 1:2:0.1) were studied in different buffer systems as a function of time. The buffer species which act as counterions to the quaternary ammonium groups in the polymer strongly affected the hydration and mechanical properties of the polymeric films. The mechanical properties of hydrated polymeric films were related to the water uptake of the films. The rate and extent of hydration determined the drug release pattern from coated dosage forms.

  16. Antimicrobial Polymeric Materials with Quaternary Ammonium and Phosphonium Salts

    PubMed Central

    Xue, Yan; Xiao, Huining; Zhang, Yi

    2015-01-01

    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. PMID:25667977

  17. boxcar, width, [buffer, /decimate] Boxcar smoothing clip, datamin, datamax, [buffer, /blank] Truncate spectrum to a min and max data value

    E-print Network

    Groppi, Christopher

    Other boxcar, width, [buffer, /decimate] Boxcar smoothing clip, datamin, datamax, [buffer, /blank] Truncate spectrum to a min and max data value decimate, [nchan, startat, buffer, ok] Decimate the spectrum, /full, /quiet, ret] Find moments of the data in the PDC gsmooth, newres, [buffer, /decimate] Gaussian

  18. A Better Reduction Theorem for Store Buffers

    E-print Network

    Cohen, Ernie

    2009-01-01

    When verifying a concurrent program, it is usual to assume that memory is sequentially consistent. However, most modern multiprocessors depend on store buffering for efficiency, and provide native sequential consistency only at a substantial performance penalty. To regain sequential consistency, a programmer has to follow an appropriate programming discipline. However, na\\"ive disciplines, such as protecting all shared accesses with locks, are not flexible enough for building high-performance multiprocessor software. We present a new discipline for concurrent programming under TSO (total store order, with store buffer forwarding). It does not depend on concurrency primitives, such as locks. Instead, threads use ghost operations to acquire and release ownership of memory addresses. A thread can write to an address only if no other thread owns it, and can read from an address only if it owns it or it is shared and the thread has flushed its store buffer since it last wrote to an address it did not own. This dis...

  19. Quaternary ammonium biocides: efficacy in application.

    PubMed

    Gerba, Charles P

    2015-01-01

    Quaternary ammonium compounds (QACs) are among the most commonly used disinfectants. There has been concern that their widespread use will lead to the development of resistant organisms, and it has been suggested that limits should be place on their use. While increases in tolerance to QACs have been observed, there is no clear evidence to support the development of resistance to QACs. Since efflux pumps are believe to account for at least some of the increased tolerance found in bacteria, there has been concern that this will enhance the resistance of bacteria to certain antibiotics. QACs are membrane-active agents interacting with the cytoplasmic membrane of bacteria and lipids of viruses. The wide variety of chemical structures possible has seen an evolution in their effectiveness and expansion of applications over the last century, including non-lipid-containing viruses (i.e., noroviruses). Selection of formulations and methods of application have been shown to affect the efficacy of QACs. While numerous laboratory studies on the efficacy of QACs are available, relatively few studies have been conducted to assess their efficacy in practice. Better standardized tests for assessing and defining the differences between increases in tolerance versus resistance are needed. The ecological dynamics of microbial communities where QACs are a main line of defense against exposure to pathogens need to be better understood in terms of sublethal doses and antibiotic resistance. PMID:25362069

  20. The phase diagram of ammonium nitrate.

    PubMed

    Chellappa, Raja S; Dattelbaum, Dana M; Velisavljevic, Nenad; Sheffield, Stephen

    2012-08-14

    The pressure-temperature (P-T) phase diagram of ammonium nitrate (AN) [NH(4)NO(3)] has been determined using synchrotron x-ray diffraction (XRD) and Raman spectroscopy measurements. Phase boundaries were established by characterizing phase transitions to the high temperature polymorphs during multiple P-T measurements using both XRD and Raman spectroscopy measurements. At room temperature, the ambient pressure orthorhombic (Pmmn) AN-IV phase was stable up to 45 GPa and no phase transitions were observed. AN-IV phase was also observed to be stable in a large P-T phase space. The phase boundaries are steep with a small phase stability regime for high temperature phases. A P-V-T equation of state based on a high temperature Birch-Murnaghan formalism was obtained by simultaneously fitting the P-V isotherms at 298, 325, 446, and 467 K, thermal expansion data at 1 bar, and volumes from P-T ramping experiments. Anomalous thermal expansion behavior of AN was observed at high pressure with a modest negative thermal expansion in the 3-11 GPa range for temperatures up to 467 K. The role of vibrational anharmonicity in this anomalous thermal expansion behavior has been established using high P-T Raman spectroscopy. PMID:22897290