Journal articles: 'Hydrogen-ion concentration'

1

TAKAHASHI, Kyoh-Ichi. "Methods measuring intracellular hydrogen ion concentration." Hikaku seiri seikagaku(Comparative Physiology and Biochemistry) 13, no. 2 (1996): 136–43. http://dx.doi.org/10.3330/hikakuseiriseika.13.136.

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Norn, M. S. "HYDROGEN ION CONCENTRATION OF TEAR FLUID." Acta Ophthalmologica 46, no. 2 (May 27, 2009): 189–200. http://dx.doi.org/10.1111/j.1755-3768.1968.tb05176.x.

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3

Gustavsson, Cart-in A.-S., Chritofer T. Lindgren, and Mikael E. Lindström. "Residual phase lignin in haft cooking related to the conditions in the cook." Nordic Pulp & Paper Research Journal 12, no. 4 (December 1, 1997): 225–29. http://dx.doi.org/10.3183/npprj-1997-12-04-p225-23.

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Abstract The amount of lignin reacting according to the slow residual phase, i.e. the residual phase lignin, is in many perspectives an interesting issue. The purpose of the present investigation was to develop a mathematical model to show how the amount of residual phase lignin in the kraft cooking of spruce chips (Picm ahies) depends on the conditions in the earlier phases of the cook. The variables studied were hydroxide ion concentration, hydrogen sulfide ion concentration and ionic strength. The liquor-to-wood ratio during pulping was very high to maintain approximately constant chemical concentrations throughout each experiment (so called "constant composition" cooks). An increase in hydroxide ion concentration andtor hydrogen sulfide ion concentration leads to a decrease in the amount of residual phase lignin, while an increase in ionic strength, i.e. sodium ion concentration, leads to an increase. A signiticant result is that the hydrogen sulfide ion concentration has a pronounced influence on the amount of residual phase lignin during a cook at a low hydroxide ion concentration. The amount of residual phase lignin expressed as % lignin on wood, L,, can be described by the following equation developed for "constant composition" cooks (when cooking with a constant sodium ion concentration of 2 mol/L): LT=0,55-0.32*[HO-](-1,3)*ln[HS-] This equation is valid for a concentration of HO- in the range from 0.17 to 1.4, and a hydrogen sulfide ion concentration from 0.07 to 0.6 mol/L.

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Shi, Laishun, Jian Gao, and Jingjing Chen. "Modeling study for oscillatory reaction of chlorite – iodide – ethyl acetoacetate." Canadian Journal of Chemistry 92, no. 5 (May 2014): 417–25. http://dx.doi.org/10.1139/cjc-2014-0072.

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Chlorine dioxide based chemical oscillating behavior was modeled by a simple scheme consisting of three component reactions. Furthermore, little is known about the influence of the pH value. In this study, four component reactions were used to model the chlorite – iodide – ethyl acetoacetate oscillating reaction by dynamic analysis software. The oscillatory phenomenon is observed for concentration changes of triiodide ion, chlorite ion, and hydrogen ion. The initial concentration of ethyl acetoacetate, chlorite ion, iodide ion, and hydrogen ion has great influence on oscillations. The amplitude and number of oscillations are associated with the initial reactant concentrations. The equation of the reaction rate of triiodide ion, chlorite ion, or hydrogen ion changing with reaction time and initial concentrations in the oscillation stage was obtained. The bifurcation surface between oscillatory and nonoscillatory behavior with different pH values was obtained. The spatial zone for the occurrence of oscillation is reduced with an increase in the pH value. The range of oscillation as concentrations of chlorine dioxide, iodine, and ethyl acetoacetate is well described by an equation. There is a lower limit on ethyl acetoacetate initial concentration for oscillation. However, there is a higher limit on chlorine dioxide and iodine concentration for oscillation. The concentrations of chlorine dioxide and iodine for oscillation decrease with an increase in the pH value. The results provide new theoretical evidence of the importance of pH value, which can affect the bifurcation surface between oscillatory and nonoscillatory behavior.

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Zhang, Lu Si, Jie Ding, Wan Qian Guo, Lei Gao, Nan Qi Ren, and Guo Xiang Zheng. "The Effect of Na-Ion on the Growth and Hydrogen Generation of Hydrogen-Producing Bacteria Yuan-3." Advanced Materials Research 455-456 (January 2012): 954–59. http://dx.doi.org/10.4028/www.scientific.net/amr.455-456.954.

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Hydrogen-producing zymogenous bacteria YUAN-3 (Ethanoligenens harbinense) is used as the study object, on which the intermittent hydrogen production test is applied to examine the influence of Na-ion concentration on the growth and gas generation of YUAN-3. Research results show that when Na ion concentration is 1.5g/L, cell concentration reaches the maximum level 0.892g/L; when Na-ion concentration is maintained at 2.0~3.0g/L, culture medium is applicable for hydrogen generation of YUAN-3.

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Beck, Mihaly T., and Gyula Rabai. "Oscillations and oligoscillations in hydrogen ion concentration." Journal of Physical Chemistry 89, no. 18 (August 1985): 3907–10. http://dx.doi.org/10.1021/j100264a029.

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Dimitrijevic, Mile, Milan Antonijevic, and Valentina Dimitrijevic. "Kinetics of pyrite oxidation by hydrogen peroxide in phosphoric acid solutions." Journal of the Serbian Chemical Society 64, no. 12 (1999): 753–64. http://dx.doi.org/10.2298/jsc9912753d.

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The kinetics of pyrite oxidation by hydrogen peroxide in phosphoric acid solutions were investigated. The effects of stirring, temperature, and particle size, as well as of the hydrogen peroxide and phosphoric acid concentrations were studied. The effect of phosphate ion addition was also examined. The oxidation kinetics was found to follow a shrinking core model, with the surface chemical reaciton as the rate-controlling step. This is in accord with an activation energy of 57 kJ/mol and a linear relationship between the rate constant and the reciprocal of the particle radius. The reaction order with respect to the hydrogen peroxide concentration was found to be equal to unity. Variation of the phosphoric acid concentration had practically no effect on the rate of pyrite oxidation. Addition of the phosphate ion in the relatively low concentration range (0.005.0.1 mol/dm 3) had a highly negative influence on the rate of pyrite oxidation, indicating that this ion has an inhibiting effect on the oxidation of pyrite by hydrogen peroxide.

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TOMODA, Susumu, and Akira SUGAWARA. "Study on hydrogen ion concentration of lapping liquid." Journal of the Japan Society for Precision Engineering 54, no. 2 (1988): 372–77. http://dx.doi.org/10.2493/jjspe.54.372.

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9

Radke, K. J., E. G. Schneider, R. E. Taylor, and R. E. Kramer. "Effect of hydrogen ion concentration on corticosteroid secretion." American Journal of Physiology-Endocrinology and Metabolism 250, no. 3 (March 1, 1986): E259—E264. http://dx.doi.org/10.1152/ajpendo.1986.250.3.e259.

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The direct effects of changes in extracellular hydrogen ion (H+) concentration on corticosteroid secretion under basal and ACTH-stimulated conditions were studied in isolated, perfused canine adrenal glands. Changes in extracellular H+ concentration were produced by altering either PCO2 or [HCO-3] of the Krebs-bicarbonate perfusate. Alkalosis markedly inhibited ACTH-stimulated aldosterone secretion. Moreover, within the range of pH from 7.19 to 7.85, there was a positive correlation between H+ concentration and the fractional secretion of aldosterone but a negative correlation between H+ concentration and the fractional secretion of corticosterone and 18-hydroxycorticosterone in response to ACTH. In contrast, neither acidosis nor alkalosis had a significant, direct effect on basal or ACTH-stimulated cortisol secretion. We conclude that 1) H+ concentration modulates the stimulatory effect of ACTH on aldosterone secretion by a direct action on the adrenal cortex, 2) acid-base disturbances are specific to the zona glomerulosa of the canine adrenal gland, and 3) H+ concentration may influence events occurring late in the pathway for aldosterone biosynthesis.

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10

Buchner, E. H. "The Hofmeister series and the hydrogen ion concentration." Recueil des Travaux Chimiques des Pays-Bas 49, no. 12 (September 3, 2010): 1150–60. http://dx.doi.org/10.1002/recl.19300491210.

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11

Koohestani, Hassan, and Amirabbas Kheilnejad. "Hydrogen Generation and Pollution Degradation from Wastewater Using TiO2–CuO Nanocomposite." Journal of Nanoscience and Nanotechnology 20, no. 9 (September 1, 2020): 5970–75. http://dx.doi.org/10.1166/jnn.2020.18544.

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Simultaneous production of hydrogen and degradation of cyanide ion and methyl red dye were successfully accomplished by employing nano-particles of TiO2–CuO under the radiation of UV light. Exploiting composites improves the electron–hole separation and consequently optimizes photocatalytic processes. Furthermore, the simultaneity of several photocatalytic processes decreases the rate of electron–hole recombination. According to the results, more hydrogen was produced in lower pHs. Up to the initial concentration of 0.3 and 0.8 mol/L for methyl red and cyanide ion respectively, the presence of pollutants increased hydrogen production remarkably, while in more concentrations, hydrogen production was independent of concentrations. The rate of hydrogen production decreased with the pass of time which is due to the consumption of holes by pollutants’ molecules, and the effective participation of the electrons in hydrogen production. Accordingly, after 210 min, the amounts of cyanide ion and methyl red declined and the hydrogen production rate decreased from from 17–22 μmol H2/min to 2–3 μmol H2/min.

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12

Kitchen, Diane L., A. M. Merritt, and J. A. Burrow. "Histamine-induced gastric acid secretion in horses." American Journal of Veterinary Research 59, no. 10 (October 1, 1998): 1303. http://dx.doi.org/10.2460/ajvr.1998.59.10.1303.

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Abstract Objective To determine gastric secretory responses in horses treated with histamine and to determine the dose of histamine needed to elicit maximal gastric secretion. Animals 6 adult horses with an indwelling gastric cannula. Procedure Gastric contents were collected in 15-minute periods, and volume, pH, hydrogen ion concentration, hydrogen ion output, sodium concentration, and sodium output were determined. Values were determined without any treatment (baseline), after administration of pyrilamine maleate (1 mg/kg of body weight, IV, given during a 15-minute period), and during 1-hour infusions of histamine at 3 rates (7.5, 15, and 30 μg/kg/h, IV). Results Volume and hydrogen ion concentration of gastric contents and hydrogen ion output were significantly increased, compared with baseline values, during histamine infusion. Mean hydrogen ion concentration and hydrogen ion output were significantly greater during infusion of histamine at a rate of 15 or 30 μg/kg/h than at a rate of 7.5 μg/kg/h. Sodium concentration was significantly decreased, compared with baseline value, during histamine infusion, but sodium output was unchanged. Conclusions Histamine at doses of 15 and 30 μg/kg/h, IV stimulated maximal gastric secretion in horses. Histamine appeared to induce only parietal secretion. Clinical Relevance This study provides additional information related to equine gastric physiology, which may benefit further understanding of the pathogenesis of peptic ulcer disease. (Am J Vet Res 1998;59:1303–1306)

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Luan, Guo Yan, Wei Ping Gao, and Ping Jing Yao. "Study on Experiments of Ion Exchange Resin Column for Purification of Hydrogen Peroxide." Advanced Materials Research 396-398 (November 2011): 596–99. http://dx.doi.org/10.4028/www.scientific.net/amr.396-398.596.

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The technologies of ion exchange resin for ultra pure hydrogen peroxide production are more and more focused. The aim of this research was to determine suitable parameters for effective removal of Na+ impurities from aqueous hydrogen peroxide solution to produce ultra pure hydrogen peroxide. Dynamic experiments for the different operation conditions, i.e., initial concentration, flow rate, ratio of height to diameter were carried out. The concentrations of Na+ of the effluents from the ion exchange resin column were determined by ICPS-7510.The breakthrough curves of Na+ were measured and analyzed. The results shown that Na+ could be reduced effectively from the experimental aqueous hydrogen peroxide solution with the fitting conditions of ion exchange resin column, which provided the basis for determining of the suitable operating conditions of ion exchange column of a pilot plant.

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14

Lan, Rui-Jia, Ji-Tai Li, Han-Wen Sun, and Wen-Bin Su. "Degradation of naproxen by combination of Fenton reagent and ultrasound irradiation: optimization using response surface methodology." Water Science and Technology 66, no. 12 (December 1, 2012): 2695–701. http://dx.doi.org/10.2166/wst.2012.508.

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A central composite factorial design methodology was employed to optimize the degradation of naproxen (NPX) by the combination of Fenton reagent and ultrasound (US) irradiation. In this study, the variables considered for the process optimization were the hydrogen peroxide, ferrous ion and NPX initial concentrations, while ultrasonic power amplitude was adjusted at 90% and initial pH was 3. An appropriate quadratic model was developed in order to plot the response surface and contour curves. Optimum dosage of Fenton reagent for NPX removal was found to be hydrogen peroxide concentration = 9.98 mmol L−1, ferrous ion concentration = 4.83 mg L−1 while NPX concentration was equal to 20 mg L−1. A degradation efficiency of 100% was achieved within 10 min under US.

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15

Alston, R. Peter, Laura Cormack, and Catherine Collinson. "Metabolic acidosis developing during cardiopulmonary bypass is related to a decrease in strong ion difference." Perfusion 19, no. 3 (May 2004): 145–52. http://dx.doi.org/10.1191/0267659104pf751oa.

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Metabolic acidosis is a frequent complication of cardio-pulmonary bypass (CPB). Commonly, its cause is ascribed to hypoperfusion; however, iatrogenic causes, related to the composition and volume of intravascular fluids that are administered, are increasingly being recognized. The aim of this study was to determine if metabolic acidosis during CPB was associated with hypoperfusion, change in strong ion difference (SID) or haemodilution. Forty-nine patients undergoing cardiac surgery using CPB in the Royal Infirmary of Edinburgh (RIE) or the HCI, Clydebank were included in the study. Arterial blood samples were aspirated before induction of anaesthesia and the end of CPB. Samples were subjected to blood gas analysis and measurement of electrolytes and lactate. Changes in concentrations were then calculated. Change variables that were found to be significant (p B-0.1) univariate correlates of the change in hydrogen ion concentration were identified and entered into a multivariate regression model with hydrogen ion concentra tion at the end of CPB as the outcome variable (r2=0.65, p<0.001). Change variance in hydrogen ion concentration was created by first entering the baseline hydrogen ion concentration into the model. Next, any variance resulting from the respiratory component of acidosis was removed by entering the change in arterial carbon dioxide tension (regression coefficient (β)=0.67, p<0.01). Change in SID (β=-0.34, p<0.01) and surgical institution (β=-0.40, p<0.01) were then found to be predictors of the remaining variance whilst change in concentration of lactate (β in=0.16, p=0.07) and volume of intravascular fluid that was administered (β=-0.07, p=0.52) were rejected from the model. These findings suggest that the metabolic acidosis developing during CPB is partially the result of iatrogenic decrease in SID rather than hypoperfusion, as estimated by lactate concentration, or haemodilution.

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Kurko, Sandra, Ljiljana Matovic, Nikola Novakovic, Snezana Nenadovic, Zoran Jovanovic, Nenad Ivanovic, and Jasmina Grbovic-Novakovic. "Changes of structural and hydrogen desorption properties of MgH2 indused by ion irradiation." Chemical Industry 64, no. 3 (2010): 227–32. http://dx.doi.org/10.2298/hemind091221034k.

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Changes in structural and hydrogen desorption properties of MgH2 induced by ion irradiation have been investigated. MgH2 powder samples have been irradiated with 45 keV B3+ and 120 keV Ar8+ions, with ion fluence of 1015 ions/cm2. The effects of ion irradiation are estimated by numerical calculations using SRIM package. The induced material modifications and their consequences on hydrogen dynamics in the system are investigated by XRD, particle size distribution and TPD techniques. Changes of TPD spectra with irradiation conditions suggest that there are several mechanisms involved in desorption process which depend on defect concentration and their interaction and ordering. The results confirmed that the near-surface area of MgH2 and formation of a substoichiometric MgHx (x<2) play a crucial role in hydrogen kinetics and that various concentrations of induced defects substantially influence H diffusion and desorption kinetics in MgH2. The results also confirm that there is possibility to control the thermodynamic parameters by controlling vacancies concentration in the system.

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Baksht, F. G., V. G. Ivanov, S. I. Kon’kov, and S. M. Shkol’nik. "Determination of the negative hydrogen ion concentration in a cesium-hydrogen discharge." Technical Physics 46, no. 8 (August 2001): 946–51. http://dx.doi.org/10.1134/1.1395113.

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18

Popov, Artemiy A., A. G. Illarionov, and S. V. Grib. "Applying the Electron Concentration Calculation Method to Assess the Influence of Hydrogen on the Position of the Variable Solubility Lines in Ti-Cr System." Solid State Phenomena 265 (September 2017): 563–68. http://dx.doi.org/10.4028/www.scientific.net/ssp.265.563.

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A possibility of using the electron concentration calculation method to evaluate Acm and Ac3 temperatures in the Ti-Cr system alloys with different hydrogen content (0.15-0.93 wt %) is considered. It is found that the proposed method gives results similar to the experimental data only in the case of low hydrogen concentrations since it does not take into account the degree of hydrogen ion screening by electrons.

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Saitou, Hiroshi, Taiichi Tanabe, Makoto Watanabe, and Akio Kanuma. "Study of Hydrogen Ion Concentration in the Periodontal Pocket." Proceeding of Japanese Society of Stomatognathic Function 5 (1987): 83–89. http://dx.doi.org/10.7144/sgf1982.5.83.

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TANAKA, Takashi. "Automatic Measuring System for Hydrogen Ion Concentration in Rainfall." Journal of Chemical Software 4, no. 3 (1998): 113–18. http://dx.doi.org/10.2477/jchemsoft.4.113.

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HUANG, Qian-Zi, Mei-Hua TANG, Zhi-Yi ZHANG, Min BIAN, Hong-Zhong BU, Er-Kang SUN, and Guo-Song CHEN. "Simplification of the Hydrogen Ion Concentration Calculation Using MATLAB." University Chemistry 31, no. 3 (2016): 78–81. http://dx.doi.org/10.3866/pku.dxhx20160378.

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Oliveira, Andrea, Mario Henrique Gonzalez, Helena Müller Queiroz, and Solange Cadore. "Fractionation of inorganic arsenic by adjusting hydrogen ion concentration." Food Chemistry 213 (December 2016): 76–82. http://dx.doi.org/10.1016/j.foodchem.2016.06.055.

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23

Dahl, Helena, and Claus Dahl. "Hydrogen ion concentration of tear fluid in newborn infants." Acta Ophthalmologica 63, no. 6 (May 27, 2009): 692–94. http://dx.doi.org/10.1111/j.1755-3768.1985.tb01582.x.

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Trotman, E. R. "Hydrogen Ion Concentration and its Application to Textile Industries." Journal of the Society of Dyers and Colourists 42, no. 7 (October 22, 2008): 208–10. http://dx.doi.org/10.1111/j.1478-4408.1926.tb01387.x.

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Jones, G. V., B. M. Wall, H. H. Williams, D. N. Presley, D. G. Sapir, and C. R. Cooke. "Modulation of plasma aldosterone by physiological changes in hydrogen ion concentration." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 262, no. 2 (February 1, 1992): R269—R275. http://dx.doi.org/10.1152/ajpregu.1992.262.2.r269.

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To assess the effect of extracellular hydrogen ion concentration (PH+) on aldosterone secretion, studies in which other known modulators could be controlled were performed on 13 patients undergoing hemodialysis. High (35 mM) or low (14-17 mM) dialysate bicarbonate concentrations were utilized on separate days to either decrease or increase PH+, while plasma potassium concentrations (PK) were held at constant levels and changes in plasma renin activity (PRA) were minimized by avoiding changes in body weight. Changes in PH+ were associated with concordant changes in plasma aldosterone concentration (Pa) in both high- and low-bicarbonate studies. When these changes in Pa in high- and low-bicarbonate studies were analyzed together as a function of corresponding changes in PH+, a significant correlation could be demonstrated (r = 0.659, P less than 0.001). There was no correlation between changes in Pa and changes in PK, plasma sodium, plasma adrenocorticotropic hormone (ACTH), or PRA. Using the same methods to control PH+ and other variables during hemodialysis, the effects of altered PH+ on ACTH-stimulated aldosterone and cortisol secretion were evaluated in studies on six patients who received incremental infusions of ACTH after pretreatment with dexamethasone. In these studies, there was no demonstrable effect of PH+ on Pa or plasma cortisol concentration. We conclude that physiological changes in PH+ have a weak modulating effect on basal aldosterone secretion that may not be evident in the presence of other acutely applied stimuli.

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Kambarov, Asadjon, Israiljon Shamshidinov, Rixsitilla Najmiddinov, Gulnoza Kodirova, Ilkham Usmanov, Diyorbek Absattorov, Bakhram Ruzibayev, and Murodjon Samadiy. "Study of the Effect of Magnesium Sulfate and Ammonium Nitrate on the Chemical Activity of Solutions of Phosphoric Acid." IOP Conference Series: Earth and Environmental Science 1275, no. 1 (November 1, 2023): 012002. http://dx.doi.org/10.1088/1755-1315/1275/1/012002.

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Abstract The present study aimed to study the effect of magnesium sulfate and ammonium nitrate on the chemical activity of phosphoric acid solutions. The results of studies on increasing the chemical activity of extractive phosphoric acid from Central Kyzylkum and Karatau phosphorites due to the concentration of the first hydrogen ions and the pH of the medium are presented. It has been shown that introducing magnesium sulfate heptahydrate into the acid reduces the concentration of the first hydrogen ions. Adding an amount of ammonium nitrate increases the concentration of the first hydrogen ions even higher than in the acid without magnesium. It has been established that the solubility of magnesium hydrophosphate increases with an increase in the content of P2O5 phosphoric acid, dihydrogen phosphate decreases as a result of dissociation with the formation of a hydrophosphate ion, and phosphoric acid dissociates with the formation of a dihydrophosphate ion, which binds with hydrogen ions, forming a dihydrophosphate ion.

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Sunaba, Toshiyuki, Susumu Hirano, and Tadao Ishihara. "Influence of Chloride for SCC Susceptibility on 15Cr Stainless Steel at High Temperatures under CO₂ Environment." Key Engineering Materials 741 (June 2017): 42–49. http://dx.doi.org/10.4028/www.scientific.net/kem.741.42.

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The effects of chloride ion concentration on SCC susceptibility of 15Cr and 13Cr martensitic stainless steels were investigated at 180°C by SSRT. Transgranular SCC occurred in the environment containing CO2 and chloride ion. The increasing chloride ion concentration was significantly affected SCC susceptibility of 15Cr SS. In addition, the contribution of hydrogen to SCC was examined at high temperature by SSRT with electrochemically polarization. The cathodically charged specimens showed hydrogen embrittlement. The fracture surface was similar to that of high temperature SCC. On the other hand, the SCC was accelerated by anodic polarization and not by cathodic polarization. The SCC behavior of martensitic stainless steel at high temperature is affect by evolved hydrogen atom. It is concluded that hydrogen plays a key role in the crack propagation.

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Oparin, R. D., and M. G. Kiselev. "Near Infrared Spectroscopy As an Effective Way of Studying Hydrogen Bonding in a LiCl–H2O–CO2 Ternary Mixture." Russian Journal of Physical Chemistry A 96, no. 4 (April 2022): 724–31. http://dx.doi.org/10.1134/s0036024422040239.

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Abstract The possibility of using near IR spectroscopy to analyze the effect isobaric heating has on hydrogen bonding in an aqueous solution of LiCl in equilibrium with supercritical carbon dioxide (a LiCl–H2O–scCO2 ternary mixture) is demonstrated in a wide range of electrolyte concentrations. It is shown that this approach is highly efficient when studying ion and molecular systems with different types of interparticle interactions. The use of near IR spectroscopy allows distinguishing spectral contributions from hydrogen bonded n-mers of bulk water and water molecules in the solvation shells of ions or in ion–water chains like those formed in solutions with extremely high electrolyte concentrations that do not contain bulk water. It is shown for the studied ternary mixture that raising the concentration of electrolyte completely neutralizes the destructive effect of carbon dioxide on the formation of a hydrogen bonded structure of water. The latter is stabilized under the influence of an ion field, which also substantially weakens the temperature effect.

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Beilke, MA, C. Collins-Lech, and PG Sohnle. "Candidacidal activity of the neutrophil myeloperoxidase system can be protected from excess hydrogen peroxide by the presence of ammonium ion." Blood 73, no. 4 (March 1, 1989): 1045–49. http://dx.doi.org/10.1182/blood.v73.4.1045.1045.

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Abstract Excessive concentrations of hydrogen peroxide inhibit the neutrophil myeloperoxidase system, presumably by inactivating the hypochlorous acid produced by this system. Ammonium ion generated by neutrophils and other cells can react with hypochlorous acid to produce monochloramine, an oxidant with good microbicidal activity, but relative resistance to inactivation by other compounds. In an assay based on the oxidation of 5-thio-2-nitrobenzoic acid, hydrogen peroxide reacted more readily with sodium hypochlorite (used as a source of hypochlorous acid) than with monochloramine. Also, in this assay Candida albicans yeast inactivated the oxidant activity of hypochlorous acid more completely than they did that of monochloramine. The killing of Candida by sodium hypochlorite, as determined in a standard colony count microbicidal assay, was inhibited by equimolar and greater concentrations of hydrogen peroxide; killing of this organism by monochloramine was not affected by a tenfold excess concentration of hydrogen peroxide. In microbicidal assays using 4 mU of myeloperoxidase and optimal or excessive concentrations of hydrogen peroxide or glucose and glucose oxidase to generate hydrogen peroxide, the excessive concentrations inhibited killing of Candida, but not Staphylococcus aureus. The inhibition of Candida killing could be reversed by addition of ammonium ion to convert hypochlorous acid to monochloramine. These results indicate that for certain organisms such as C albicans, conversion of hypochlorous acid to monochloramine by reactions with ammonium ion may extend the range of hydrogen peroxide concentrations under which killing by the myeloperoxidase system can occur by protecting the necessary microbicidal oxidants from inactivation by excess hydrogen peroxide.

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Beilke, MA, C. Collins-Lech, and PG Sohnle. "Candidacidal activity of the neutrophil myeloperoxidase system can be protected from excess hydrogen peroxide by the presence of ammonium ion." Blood 73, no. 4 (March 1, 1989): 1045–49. http://dx.doi.org/10.1182/blood.v73.4.1045.bloodjournal7341045.

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Excessive concentrations of hydrogen peroxide inhibit the neutrophil myeloperoxidase system, presumably by inactivating the hypochlorous acid produced by this system. Ammonium ion generated by neutrophils and other cells can react with hypochlorous acid to produce monochloramine, an oxidant with good microbicidal activity, but relative resistance to inactivation by other compounds. In an assay based on the oxidation of 5-thio-2-nitrobenzoic acid, hydrogen peroxide reacted more readily with sodium hypochlorite (used as a source of hypochlorous acid) than with monochloramine. Also, in this assay Candida albicans yeast inactivated the oxidant activity of hypochlorous acid more completely than they did that of monochloramine. The killing of Candida by sodium hypochlorite, as determined in a standard colony count microbicidal assay, was inhibited by equimolar and greater concentrations of hydrogen peroxide; killing of this organism by monochloramine was not affected by a tenfold excess concentration of hydrogen peroxide. In microbicidal assays using 4 mU of myeloperoxidase and optimal or excessive concentrations of hydrogen peroxide or glucose and glucose oxidase to generate hydrogen peroxide, the excessive concentrations inhibited killing of Candida, but not Staphylococcus aureus. The inhibition of Candida killing could be reversed by addition of ammonium ion to convert hypochlorous acid to monochloramine. These results indicate that for certain organisms such as C albicans, conversion of hypochlorous acid to monochloramine by reactions with ammonium ion may extend the range of hydrogen peroxide concentrations under which killing by the myeloperoxidase system can occur by protecting the necessary microbicidal oxidants from inactivation by excess hydrogen peroxide.

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Malla, Komal Prasad, Bishnu Prasad Neupane, Bindu Malla, Anil Gautam, and Dinesh Chaudhary. "Sulfide ion Selective Method of Analysis of Sulfurated Hydrogen in Alkaline Smoked Cigarette Solution." Journal of Health and Allied Sciences 5, no. 1 (November 21, 2019): 67–71. http://dx.doi.org/10.37107/jhas.39.

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Sulfurated hydrogen commonly called hydrogen sulfide (H2 S) is a clear, colorless, extremely toxic gas that has a rotten egg smell at low concentration. The human nose can detect H2 S at concentrations below 100 parts per billion (ppb). It is found least amount in cigarette smoke that has been the subject of analysis for many analytical chemists. This gases is soluble in alkaline medium and gives free sulfide (S-2 ) ions. Sulfide ion concentration in cigarette smoke solution is found in the range of detection limit of lab made Silver- silver sulfide (Ag/Ag2 S) ion selective electrode (ISE).This project has designed to investigate the amount hydrogen sulfide as a free sulfide (S--)ion in cigarette smoke solution. Silver-silver sulfide ion selective electrode (Ag/ Ag2 S ISE) and Silver–silver chloride (Ag/AgCl) reference electrode are prepared in the lab for determination. Detail protocol of standard addition method with modified Grant’s plot is applied for estimation. Different brand of cigarette samples were collected from different area of Pokhara valley and analyzed. The average amount of H2 S per stick of cigarette smoke is found to vary from 0.0453 mg to 0.0573 mg in different brands. Among them sample no SA-5 shows 0.0453mg per stick of cigarette. This result is minimum in compare to other brands. Similarly, sample no SA- 7 have found 0.0573mg per stick which is higher in compare to other brands. Key words: Cigarette smoke, hydrogen sulfide, ion selective electrode, standard addition method, Grant’s plot method,

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TOMODA, Susumu, and Akira SUGAWARA. "Study on Hydrogen Ion Concentration of Lapping Liquid (2nd Report)." Journal of the Japan Society for Precision Engineering 56, no. 1 (1990): 158–63. http://dx.doi.org/10.2493/jjspe.56.158.

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Kowalchuk, J. M., G. J. Heigenhauser, M. I. Lindinger, J. R. Sutton, and N. L. Jones. "Factors influencing hydrogen ion concentration in muscle after intense exercise." Journal of Applied Physiology 65, no. 5 (November 1, 1988): 2080–89. http://dx.doi.org/10.1152/jappl.1988.65.5.2080.

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To assess the importance of factors influencing the resolution of exercise-associated acidosis, measurements of acid-base variables were made in nine healthy subjects after 30 s of maximal exercise on an isokinetic cycle ergometer. Quadriceps muscle biopsies (n = 6) were taken at rest, immediately after exercise, and at 3.5 and 9.5 min of recovery; arterial and femoral venous blood were sampled (n = 3) over the same time. Intracellular and plasma inorganic strong ions were measured by neutron activation and ion-selective electrodes, respectively; lactate concentration ([La-]) was measured enzymatically, and plasma PCO2 and pH were measured by electrodes. Immediately after exercise, intracellular [La-] increased to 47 meq/l, almost fully accounting for a reduction in intracellular strong ion difference ([SID]) from 154 to 106 meq/l. At the same time, femoral venous PCO2 increased to 100 Torr and plasma [La-] to 9.7 meq/l; however, plasma [SID] did not change because of a concomitant increase in inorganic [SID] secondary to increases in [K+], [Na+], and [Ca2+]. During recovery, muscle [La-] fell to 26 meq/l by 9.5 min; [SID] remained low (101 and 114 meq/l at 3.5 and 9.5 min, respectively) due almost equally to the elevated [La-] (30 and 26 meq/l) and reductions in [K+] (from 142 meq/l at rest to 123 and 128 meq/l). Femoral venous PCO2 rose to 106 Torr at 0.5 min postexercise and fell to resting values at 9.5 min.(ABSTRACT TRUNCATED AT 250 WORDS)

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KRONFELD, D. S., P. L. FERRANTE, LYN E. TAYLOR, and W. TIEGS. "Partition of plasma hydrogen ion concentration changes during repeated sprints." Equine Veterinary Journal 31, S30 (June 10, 2010): 380–83. http://dx.doi.org/10.1111/j.2042-3306.1999.tb05252.x.

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Wanqing, Luo. "The characterization of hydrogen ion concentration in sequential cumulative rainwater." Atmospheric Environment 35, no. 35 (December 2001): 6219–25. http://dx.doi.org/10.1016/s1352-2310(01)00235-7.

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36

Bunge, A. L., and C. J. Radke. "The Origin of Reversible Hydroxide Uptake on Reservoir Rock." Society of Petroleum Engineers Journal 25, no. 05 (October 1, 1985): 711–18. http://dx.doi.org/10.2118/11798-pa.

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Abstract When reservoir solids reversibly consume hydroxide, the impact on alkaline-waterflood performance can be significant. Only recently has this reaction been recognized as a principal factor influencing oil recovery rates and chemical-pulse depletion. This paper considers the origin of the reversible hydroxide uptake to be ion exchange of sodium for hydrogen ions. Using a simple, mass-action equilibrium model, we describe the alkali exchange isotherm. Because hydronium and hydroxide concentrations in water are never zero, hydroxide uptake must be reported relative to a reference pH and salinity. With the recognition of a reference state pH and salinity. With the recognition of a reference state and with the mass-action model, we predict qualitatively the effects of pH, salt concentration, and temperature on the measured hydroxide uptake isotherms for the Wilmington, Ranger-zone sand. Mineral sites that exchange ions of sodium for hydrogen may also exchange calcium for hydrogen or for sodium. Using simple mass-action equilibria again, we demonstrate that reversible hydroxide uptake depends on hardness concentration and that calcium/sodium exchange is pH dependent. Introduction Alkaline flooding is a technique in which chemical interactions with reservoir minerals are of paramount importance to success or failure. Hydroxide consumption falls into three broad categories:reversible rock adsorption or ion exchange,congruent and incongruent mineral dissolution, andprecipitation of insoluble hydroxides. All three loss mechanisms have been considered in various levels of detail. Reversible hydroxide ion uptake, which was overlooked in earlier work on alkali/rock interactions, is, perhaps, the least transparent consumption reaction. Its perhaps, the least transparent consumption reaction. Its existence and importance have come to light only recently. In modeling the alkaline oil recovery process, de Zabala et al. point out that equilibrium hydroxide ion uptake causes a chromographic lag in caustic and in the accompanying in-situ generated surfactants, which in turn slows oil-production rates. Likewise, Bunge and Radke demonstrate that hydroxide ion uptake alone can diminish an alkaline chemical pulse to ineffective concentration levels. Thus, even if caustic consumption by dissolution and precipitation could be eliminated, ion-exchange delay can precipitation could be eliminated, ion-exchange delay can limit the success of alkaline EOR. Therefore, when a reservoir is considered for possible alkaline flooding, understanding and quantifying any alkali/rock ion exchange is necessary. This paper presents a simple, mass-action treatment of reversible hydroxide ion uptake by sodium/hydrogen ion exchange followed by a reaction to form or dissociate water. We refer to this overall reaction scheme as hydroxide uptake, or reversible hydroxide consumption. By using the mass-action model and by paying careful attention to the measurement of alkali exchange isotherms, we show how the effects of pH, salt content, and temperature on the hydroxide uptake isotherms may be explained. The relationship between sodium/hydrogen exchange and calcium/sodium exchange is also explored. We demonstrate that calcium/sodium exchange is a combination of sodium/hydrogen and calcium/hydrogen exchange. Therefore, calcium/sodium exchange isotherms generally must be a function of pH, and hydroxide exchange isotherms must depend on calcium concentration. Finally, the connection between the hydrogen exchange capacity (HEC) and the calcium exchange capacity (CEC) is elucidated. Sodium/Hydrogen Exchange Fig. 1 gives the reversible hydroxide uptake on Wilmington, Ranger-zone sand as a function of hydroxide concentration at three temperatures with and without NaCl. Although there is considerable scatter in the data and few points at the lower pH values, the uptake isotherms appear Langmuir in shape. Also, alkali exchange increases with increasing temperature but decreases when salt is added. Reversible alkali exchange occurs not only with the unconsolidated reservoir materials shown here but also on consolidated Berea sandstone. To quantify the behavior of reversible surface uptake of hydroxide ions on reservoir minerals, we adopt our previous. ture of weak-acid sodium/hydrogen cation previous. ture of weak-acid sodium/hydrogen cation exchange: MOH+Na+ + MONa+H+................... (1) where M represents a mineral exchange site. For oxides (such as silica) MOH denotes a hydrolyzable acid site, while for clay minerals (such as kaolinite or montmorillonite MOH denotes a negative lattice exchange site occupied by a hydronium ion. SPEJ P. 711

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Liu, Chao Zhuo. "Analysis of Hydrogen Content in Hydride Film by Elastic Recoil Method." Advanced Materials Research 457-458 (January 2012): 170–73. http://dx.doi.org/10.4028/www.scientific.net/amr.457-458.170.

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The essential principle of elastic recoil detection analysis (ERDA) of hydrogen content in the film and the experimental method were described briefly. The energy spectrum of the recoiled hydrogen atom can be obtained by the elastic collision of incident ion beam with hydrogen atoms in film, and the spectrum can be transferred easily into hydrogen concentration and depth profile. For illustrating the application of ERDA in hydrogen storage research, a beam of helium ion was used to recoil hydrogen in titanium hydride and deuteride film to obtain hydrogen contents and depth profiles. This technique was believed to be powerful in determining hydrogen content in hydride films.

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Noor, Ehteram A., and Fatma M. Al-Solmi. "Analysis of Adsorption, Ion Exchange, Thermodynamic Behaviour of Some Organic Cations on Dowex 50WX4-50/H+Cation Exchanger in Aqueous Solutions." E-Journal of Chemistry 8, s1 (2011): S171—S188. http://dx.doi.org/10.1155/2011/963603.

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The equilibrium adsorption, ion exchange characteristics of various concentrations of some organic cations from aqueous solutions onto dowex 50WEX/H+cation exchanger were studied at different temperatures in the range of 30-50 °C. The studied cations showed good adsorptive properties onto dowex 50WX4-5/H+at different concentrations and temperatures. Main adsorption behaviour was ion exchange between hydrogen ions and the organic cations as indicated from the linear relation between the initial concentration of the organic cations and the released hydrogen ions. It was found that the adsorption affinity of dowex 50WX4-50/H+towards the studied organic cations depends on the substituent type of the organic cations giving the following increasing order: 1-H < 2-OH < 3-OCH3. Thermodynamic parameters for the adsorption of the studied organic cations were evaluated and discussed. It was found that the adsorption 1-H organic cation was spontaneous, ordered, exothermic and favored with decreasing temperature. On the other hand the adsorption of both 2-OH and 3-OCH3organic cations was found to be spontaneous and disordered with enthalpy change varies significantly with increasing organic cation concentration, suggesting dipole-dipole adsorption forces as new active sites for adsorption under conditions of relatively high concentrations. Freundlich and Dubinin-Radushkevich adsorption isotherm models reasonably describe the adsorption of the studied organic cations onto dowex 50WX4-50/H+by segmented straight lines depending on the studied range of concentration, indicating the existence of two different sets of adsorption sites with substantial difference in energy of adsorption. According to Dubinin-Radushkevich adsorption isotherm model, physical-ion exchange mechanism was suggested for the adsorption of 1-H organic cation and both physical and chemical-ion exchange mechanisms were suggested for the adsorption of 2-OH and 3-OCH3organic cations depending on the studied range of concentration.

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Kraig, R. P., and A. J. L. Cooper. "Bicarbonate and ammonia changes in brain during spreading depression." Canadian Journal of Physiology and Pharmacology 65, no. 5 (May 1, 1987): 1099–104. http://dx.doi.org/10.1139/y87-172.

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An alkaline, followed by an acid-going transient, characterizes acid-base changes in the interstitial space during spreading depression in a variety of brain structures. In rat, such changes are associated with a significant rise in brain lactate content. How brain proton buffers behave during spreading depression is unknown. Techniques to significantly improve the response time of gas permeable membrane semimicroelectrodes for carbon dioxide and ammonia are reported. Measurements with such electrodes, when coupled to measurements of hydrogen ion concentration (from microelectrodes), permit rapid changes to be determined in bicarbonate concentration or ammonia and ammonium ion concentration, respectively. Bicarbonate concentration fell from 30 ± 1 (n = 16) to 14 ± 1 mM (n = 16) during spreading depression. On the other hand, ammonia concentration rose from 2.3 ± 0.1 to 4.4 ± 0.3 μM (n = 17) while ammonium ion concentration rose from 116 ± 11 (n = 17) to 382 ± 30 μM (n = 17) during spreading depression. Bicarbonate changes probably reflect titration of brain bicarbonate stores by accumulated lactic acid. Similar physicochemical changes do not explain the rise in ammonia and ammonium ion concentrations. Instead, elevation of the latter can only result from an increase in ammonia content of the interstitial space.

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Pokorný, Petr, Vítězslav Vacek, Nikola Prodanovic, Adam Zabloudil, Jaroslav Fojt, and Viktor Johánek. "The Influence of Graded Amount of Potassium Permanganate on Corrosion of Hot-Dip Galvanized Steel in Simulated Concrete Pore Solutions." Materials 15, no. 21 (November 7, 2022): 7864. http://dx.doi.org/10.3390/ma15217864.

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This paper evaluates the amount of KMnO4 in simulated concrete pore solution (pH 12.8) on the corrosion behaviour of hot-dip galvanized steel (HDG). In the range of used MnO4− (10−4, 10−3, 10−2 mol·L−1), corrosion behaviour is examined with regard to hydrogen evolution and composition (protective barrier properties) of forming corrosion products. The corrosion behaviour of HDG samples is evaluated using Rp/Ecorr and EIS. The composition of corrosion products is evaluated using SEM, XRD, XPS and AAS. The effective MnO4− ion concentration to prevent the corrosion of coating with hydrogen evolution is 10−3 mol·L−1; lower concentrations only prolong the time to passivation (corrosion with hydrogen evolution). The highest used MnO4− concentration ensures corrosion behaviour without hydrogen evolution but also leads to the formation of less-protective amorphous corrosion products rich in MnII/MnIII phases.

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Zou, Zhiqiang, Lijinhong Huang, Xindong Li, Jie Xu, Xiangrong Zeng, Ronghua Shu, Bin Xiao, Jiacai Ou, and Wanfu Huang. "Adsorption of Hydrated Pr3+ and NH4+/Mg2+ Ions onto the (001) Surface of Montmorillonite: A DFT Analysis with Experimental Verification." Minerals 12, no. 11 (November 18, 2022): 1454. http://dx.doi.org/10.3390/min12111454.

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Montmorillonite is a major mineral present in ion-adsorption rare earth ores, and the microscopic adsorption states of rare earth ions on its surface are of a great significance for the efficient exploitation of ion-adsorption rare earth ores. In this article, density functional theory calculations were used to investigate the adsorption mechanisms and bonding characteristics of hydrated Pr, Mg and NH4 ions on the (001) surface of montmorillonite. Pr3+ exhibited a directed tendency geometry with Pr(H2O)103+, which was adsorbed onto montmorillonite by hydrogen bonding with an adsorption energy of −1182 kJ/mol, and one coordinated H2O ligand was separated from the first hydration layer of Pr. Both hydrated Mg and NH4 ions were adsorbed onto the montmorillonite surface through hydrogen bonds, and the adsorption energies were −206 and −188 kJ/mol, respectively, indicating that the adsorption stability of the hydrated Mg ion was slightly higher than that of the hydrated NH4 ion, but both were lower than that of hydrated Pr (−1182 kJ/mol). Hence, higher concentrations of Mg and NH4 ions than rare earth ions would be necessary in the leaching process of ion-adsorption rare earth ores. Additionally, desorption experiments revealed that the recovery of Pr3+ by Mg2+ with a concentration of 38 mmol/L is 80%, while it is only 65% with the same concentration of NH4+, and the concentrations of Mg2+ and NH4+ were much higher than that of Pr3+ in lixivium, which is consistent with the DFT calculations.

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Restrepo, Gloria M., Alejandro Rincón, and Óscar J. Sánchez. "Kinetic Analysis of Gluconacetobacter diazotrophicus Cultivated on a Bench Scale: Modeling the Effect of pH and Design of a Sucrose-Based Medium." Fermentation 9, no. 8 (July 26, 2023): 705. http://dx.doi.org/10.3390/fermentation9080705.

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Gluconacetobacter diazotrophicus is an endophytic bacterium that has shown important plant growth-promoting properties. During the growth of G. diazotrophicus with high carbon source concentrations, organic acids are produced, and pH decreases, thus inhibiting biomass growth. The objective of this work was to design a sucrose-based medium and perform a kinetic analysis of the batch submerged cultivation of this bacterium in a 3 L stirred-tank bioreactor without pH control. A mathematical model was proposed for representing G. diazotrophicus concentration, considering the inhibitory effect of hydrogen ion concentration. It comprises a biomass growth model, a specific growth rate expression that accounts for the inhibitory effect of hydrogen concentration, and a hydrogen model that represents the relationship between hydrogen and biomass concentrations. The sucrose-based medium proved its suitability for G. diazotrophicus growth. A higher biomass concentration (1.10 g/L) was obtained in a modified LGI-P medium containing 30 g/L sucrose with a three-fold increase in biomass production relative to the initial inoculation. The model allowed a satisfactory description of the experimental data obtained, and it could be used to design a cultivation strategy to maximize biomass production leading to the production of an alternative microbial inoculant for plant growth promotion of economically important crops.

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Pradhananga, Raja Ram, A. Nyachhyon, A. P. Yadav, Lok Kumar Shrestha, and S. Tandukar. "Fabrication and Applications of Silver Sulphide Based Ion Sensors." Advanced Materials Research 117 (June 2010): 7–14. http://dx.doi.org/10.4028/www.scientific.net/amr.117.7.

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An electrochemical sensor based on the silver sulphide precipitate was fabricated in the laboratory and characterized by x-ray diffraction, SEM equipped with EDAX, and electrochemical techniques. Ion selective electrode (ISE) was found to be sensitive enough to sense the sulphide ion concentration from 10-1 to 10-5 M in alkaline medium. The change in electrode potential per decade change in sulphide ion concentration was found to be 31.5 mV at laboratory temperature indicating adherence of the ion selective electrode to Nernst’s equation. The sensor have been successfully used for the quantitative determination of thiamine in pharmaceutical preparations, hydrogen sulphide in cigarette smoke and determination of solubility products of sparingly soluble silver salts. A trace amount of hydrogen sulphide, a toxic gas, is present in the cigarette smoke. The quantitative estimation of hydrogen sulphide in cigarette smoke is a challenging task to analytical chemist. Hydrogen sulphide in cigarette smoke had been determined by absorbing the cigarette smoke in 0.1 M sodium hydroxide and the resulting solution was analyzed using silver sulphide based ion sensor by standard addition technique using modified Gran plot. The average amounts of hydrogen sulphide produced by a stick of cigarette in 8 different brands of Nepalese cigarette ware found to range from 0.0332 mg to 0.0766 mg. The sensitivity and reliability of these home made ion sensors were excellent and in par with commercial electrodes. For developing countries like Nepal, who can not afford to procure high cost commercial ion selective electrodes, these home made ion sensors are especially appealing since the sensor can be fabricated with ease from the materials that are readily available in the chemistry laboratory and the sensor is quite sensitive and gives reproducible results which are sufficiently accurate for the analysis with ion selective electrodes.

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Chang, F. Y., and C. Y. Lin. "Calcium effect on fermentative hydrogen production in an anaerobic up-flow sludge blanket system." Water Science and Technology 54, no. 9 (November 1, 2006): 105–12. http://dx.doi.org/10.2166/wst.2006.867.

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The effects of calcium ions on a granular fermentative hydrogen production system were investigated in four lab-scale UASB reactors that fed on sucrose (20 g COD/L). The reactors were seeded with anaerobic sewage sludge microflora and operated at a temperature of 35±1°, pH of 6.7 with hydraulic retention times (HRTs) of 24–6 h. The experimental results indicated that calcium ion addition (75∼150 mg/L) could enhance the granulation and elevate hydrogen production efficiency. However, an overly-high calcium concentration (300 mg-Ca+2/L) deteriorated the hydrogen productivity. A calcium concentration of 150 mg-Ca+2/L resulted in a peak HP of 3.6 mol H2/mol-sucrose and HPR of 807 mmol-H2/L-d at HRTs of 8 and 6 h, respectively. The EPS concentration of biohydrogenic biomass was higher than that of the aerobic or methanogenic biomass. The protein/carbon-ratio ranged from 0.17 to 0.26%. The multinomial regression analysis shows that the 75∼150 mg-Ca+2/L calcium concentrations and HRT of 6 h were the optimal operating conditions to efficiently produce hydrogen.

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Krakhella, Kjersti, Robert Bock, Odne Burheim, Frode Seland, and Kristian Einarsrud. "Heat to H2: Using Waste Heat for Hydrogen Production through Reverse Electrodialysis." Energies 12, no. 18 (September 5, 2019): 3428. http://dx.doi.org/10.3390/en12183428.

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This work presents an integrated hydrogen production system using reverse electrodialysis (RED) and waste heat, termed Heat to H 2 . The driving potential in RED is a concentration difference over alternating anion and cation exchange membranes, where the electrode potential can be used directly for water splitting at the RED electrodes. Low-grade waste heat is used to restore the concentration difference in RED. In this study we investigate two approaches: one water removal process by evaporation and one salt removal process. Salt is precipitated in the thermally driven salt removal, thus introducing the need for a substantial change in solubility with temperature, which KNO 3 fulfils. Experimental data of ion conductivity of K + and NO 3 − in ion-exchange membranes is obtained. The ion conductivity of KNO 3 in the membranes was compared to NaCl and found to be equal in cation exchange membranes, but significantly lower in anion exchange membranes. The membrane resistance constitutes 98% of the total ohmic resistance using concentrations relevant for the precipitation process, while for the evaporation process, the membrane resistance constitutes over 70% of the total ohmic resistance at 40 ∘ C. The modelled hydrogen production per cross-section area from RED using concentrations relevant for the precipitation process is 0.014 ± 0.009 m 3 h − 1 (1.1 ± 0.7 g h − 1 ) at 40 ∘ C, while with concentrations relevant for evaporation, the hydrogen production per cross-section area was 0.034 ± 0.016 m 3 h − 1 (2.6 ± 1.3 g h − 1 ). The modelled energy needed per cubic meter of hydrogen produced is 55 ± 22 kWh (700 ± 300 kWh kg − 1 ) for the evaporation process and 8.22 ± 0.05 kWh (104.8 ± 0.6 kWh kg − 1 ) for the precipitation process. Using RED together with the precipitation process has similar energy consumption per volume hydrogen produced compared to proton exchange membrane water electrolysis and alkaline water electrolysis, where the energy input to the Heat to H 2 -process comes from low-grade waste heat.

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Lin, Po-Yen, Po-Chen Lin, and Chien-Jung Huang. "High Hydrogen Ion Concentration Causes a Blue Shift in Gold Nanoparticles." Crystals 11, no. 2 (January 28, 2021): 132. http://dx.doi.org/10.3390/cryst11020132.

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In this research, our team used a rare electrochemical method to obtain gold nanoparticles (GNPs). The growth solution has been added with nitric acid in order to observe the effect of GNPs. The solution also included cetyltrimethylammonium bromide (CTAB) and acetone. All reactions involved the oxidation of acetone and chain polymerization. Therefore, the GNPs changed to a su pramolecular structure. In addition, our team measured absorption wavelength via ultraviolet/ visible spectrophotometer and found an obviously blue shift. This short absorption wavelength is obviously different from other GNPs.

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Bronstein, E. H., and R. J. Porcelli. "Effect of Hydrogen Ion Concentration on in vitro Pulmonary Vascular Reactivity." Experimental Lung Research 14, no. 6 (January 1988): 837–51. http://dx.doi.org/10.3109/01902148809087848.

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KAMEI, Takeshi, and Hiroaki SANO. "Influence of Hydrogen-Ion Concentration Exponent on Engineering Properties of Bentonites." Landslides 30, no. 2 (1993): 30–40. http://dx.doi.org/10.3313/jls1964.30.2_30.

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KAMEI, Takeshi, and Hiroaki SANO. "Influence of Hydrogen-ion Concentration Exponent on Shear Characteristics of Bentonites." Landslides 31, no. 3 (1994): 37–42. http://dx.doi.org/10.3313/jls1964.31.3_37.

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FINK, MITCHELL P., STEPHEN M. COHN, PATRICK C. LEE, HEIDIE R. ROTHSCHILD, YAMO F. DENIZ, HAILONG WANG, and RICHARD G. FIDDIAN-GREEN. "Effect of lipopolysaccharide on intestinal intramucosal hydrogen ion concentration in pigs." Critical Care Medicine 17, no. 7 (July 1989): 641–46. http://dx.doi.org/10.1097/00003246-198907000-00009.

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Journal articles on the topic 'Hydrogen-ion concentration'

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