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Buffer solutions with dissolved

Sulfur Dioxide Vapor Pressure and pH of Sodium Citrate Buffer Solutions with Dissolved Sulfur Dioxide... [Pg.269]

Buffer solutions with pH values around 10 are prepared using sodium carbonate (Na2 CO3) and sodium hydrogen carbonate (NaHC03). What is the pH of a solution prepared by dissolving 10.0 g each of these two salts in enough water to make 0.250 L of solution ... [Pg.1280]

Dissolve polyvinyl pyrrolidone-iodine and Lutrol F 127 in the mixture of the buffer solutions with Lutrol E 400. [Pg.177]

In this study we performed initial rate experiments, reacting H2S with lepidocrocite (23). The consumption of H2S was measured continuously by using a pH2S electrode cell (25). To avoid interferences of pH buffer solutions with the iron oxide surface, the pH was stabilized by using a pH-stat that added appropriate amounts of HC1 to the solution. The added volume, which was also continuously monitored, provided information about the amount of protons consumed during the reaction. Dissolved iron was measured only in some runs. [Pg.373]

Figure 10.4 Introduction of CHCs derived from ant body surface into aquatic environment with CjapCSP. A. Gas chromatograms for the original CHC profiles of three different colonies. B. CHC profiles dissolved in plane buffer solution or in buffer solution with Cj apCSP or bovine serum albumin (BSA), or in plane buffer. Figure 10.4 Introduction of CHCs derived from ant body surface into aquatic environment with CjapCSP. A. Gas chromatograms for the original CHC profiles of three different colonies. B. CHC profiles dissolved in plane buffer solution or in buffer solution with Cj apCSP or bovine serum albumin (BSA), or in plane buffer.
Mobile phase MeOH btiffer 70 30 (Prepare buffer solution by dissolving 14.05 g sodium perchlorate in water, adjust pH to 2.0, make up to 1 L with water.)... [Pg.762]

The buflFer solution used above was prepared by dissolving 62.5 grams reagent grade ammonium acetate (NH4C2H3O2) in about 200 ml. deionized water. Add exactly 17.5 ml. glacial acetic acid and dilute to 250 ml. Remove possible meal contaminants by adding 20 ml. of a 5% sodium diethyldithiocarbamate solution and extract the buffer solution with two 50-ml. portions of methyl isobutyl ketone. [Pg.250]

In addition to ESI, a relative new laser desorption mass spectrometry method termed laser-induced liquid bead ion desorption mass spectrometry (LILBID-MS) has been established [12], Here, preferentially monodisperse macromolecules, especially biomolecules, dissolved in microdroplets are desorbed/ablated by a mid-IR laser into vacuum [12, 13]. Two modes of desorption are addressable an ultrasoft mode at lower laser intensity in which, for example, a macromolecule complex is desorbed into vacuum and a harsher mode at higher laser intensity by which it is dissociated into its covalent subunits. A broad range of molar masses of biohybrid stmctures and transmembrane protein complexes, etc. can be determined up to 1,000,000g/mol, as long as the to be analyzed macromolecular structures can be dissolved in water or in buffer solution with low ionic strength. With this LILBID-MS molar masses of water-soluble glycodendrimers and their complexes with inorganic Re clusters are determinable (Fig. 4.8) [14],... [Pg.132]

II, and III, obtained with two antigens (VI and X) and three antisera (C, E, and F), that the antigen-antibody precipitate is either dissolved slightly or carried away mechanically by the saline or borate buffer solutions with which it is washed. The loss in this way is, however, small, amounting to about 5 to 15% for eight or ten extra washings with 10-ml. portions of solution. [Pg.87]

Instrument. H-nmr spectra and C-nmr spectra were measured using a JEOL JNM-MH-100 NMR spectrometer and a JEOL FX-90Q spectrometer, respectively. The samples for C-FT-nmr measurement were dissolved in DMSO-d0 at 70with TMS as an external reference with 4000-45000 pulses. Circular dichroism was measured, using a JASC0-500C spectrometer, in pH 7.2 Tris-HCl buffering solution with a 0.1 or 0.01 dm cell respectively. [Pg.662]

Calculate the mass of sodium propanoate (M= 96.07gmoh ) that must be dissolved in I.OOdm of 1,00moldm-3 propanoic acid (p/Cg = 4.87) to give a buffer solution with a pH of 4.5. (Let x represent the concentration of propanoate ions and y represent the amount of sodium propanoate.)... [Pg.623]

Other studies have also analyzed the degradation of pSi layers in SBFs [68, 78]. Both, inductively coupled plasma (ICP) and mass spectroscopy (MS) measurements of solutions containing porosified wafers were used to determine the amount of dissolved pSi from 64%, 83% and 88% porosity layers over 24h at different pH levels. Triplicate experiments were performed on five different buffered solutions with pH values of 2, 4, 6, 7 and 8, after which ICP-MS was used to determine the amount of silicon in solution at different time points [68]. At pH 7, medium-porosity (62%) pSi showed almost no dissolution at 6h, and very little at 24 h. Both, high (83%) and very high (88%) -porosity films showed an exponential increase in silicon dissolution over time, with a maximum of 61.3 7.6% for high-porosity films and 45.5 3.3% for very high-porosity films [68] (Figure 11.12). Dissolution at 6 and 24h under different pH conditions showed a positive correla-... [Pg.378]

This paper reports the results so far on tests of the usefulness of the programme imder more realistic conditions. The first phase involved spiking aqueous buffer solutions with mixtures of different activities of Sr-85, Sr-89 and Sr-90+Y-90. Y(OH)3 was then precipitated from these solutions to remove Y-90. The Sr nuclides were then concentrated by precipitating SrCOs. The SrCOs was dissolved and transferred to a scintillation vial, mixed with the usual cocktail and tracers then measured by LSC. Here, Sr losses are expected, spurious cross-contaminations in the laboratory are possible, and Y-90 grows in during the analysis and measurement procedure. In a second test phase, the laboratory participated in an interlaboratory comparison with raw milk spiked with Sr-89 and Sr-90 as well as potentially interfering nuclides 1-131, Ba-133, Cs-134 and Cs-137. A known activity of Sr-85 tracer was added directly to aliquots of sub-samples of the raw milk prior to radiochemical separation and preparation for LSC by a rapid method ll... [Pg.42]

An automatic titrator is used, connected to a conductivity meter with millivolt output. A 5-mL buret glassware unit is suitable. Weigh a sample of about 4 g into a 100-mL volumetric flask and dissolve and dilute to volume with 1 1 THF/water. Depending on the expected S04 content, transfer an aliquot of 1 to 10 mL into the conductometric titration cell. Add 5 mL acetate buifer solution (pH 4.62) and 5 mL THF as well as 1 or 2 drops of an aqueous suspension of barium sulfate (freshly shaken). If the liquid level of the cell is too low, add 1 1 THF/water as necessary to properly immerse the electrodes. Thermostat the cell at 25°C (or other convenient temperature) and titrate with 0.1 M barium acetate solution (dissolved in 1 1 THF/water, in which 20% of the water is the pH 4.62 acetate buffer solution) with stirring. [Pg.16]

To prepare the standard pH buffer solutions recommended by the National Bureau of Standards (U.S.), the indicated weights of the pure materials in Table 8.15 should be dissolved in water of specific conductivity not greater than 5 micromhos. The tartrate, phthalate, and phosphates can be dried for 2 h at 100°C before use. Potassium tetroxalate and calcium hydroxide need not be dried. Fresh-looking crystals of borax should be used. Before use, excess solid potassium hydrogen tartrate and calcium hydroxide must be removed. Buffer solutions pH 6 or above should be stored in plastic containers and should be protected from carbon doxide with soda-lime traps. The solutions should be replaced within 2 to 3 weeks, or sooner if formation of mold is noticed. A crystal of thymol may be added as a preservative. [Pg.933]

Apply indole derivatives dissolved in sodium bo- [105] rate buffer solution (c = 0 2 mol/1, pH 9 0) — ethanol (1 -I-1) Dip TLC plate in fluorescamine solution to just above starting zone (15 s) Then dry at room temperature and develop In case of indole amines followed by spraying with 40% perchloric acid... [Pg.76]

Citrate buffer solution Dissolve 210 g citric acid in 400 ml caustic soda solution (c = 5 mol/1) and make up to 11 with water. Mix 530 ml of this solution with 470 ml caustic soda solution (c = 1 mol/1) and adjust to pH 6.6 with caustic soda solution or citric acid [1]. [Pg.267]

An amount of enzyme preparation equivalent to 900 mg of wet cells was made up to 25 ml with the above potassium phosphate buffer solution. 150 mg (1.15 mmol) of 5-fluorouracil and 1.0 gram of thymidine (4.12 mmol) were dissolved in 15 ml of the above potassium phosphate buffer solution. The mixture was incubated at 37°C for 18 hours. After this time, enzyme action was stopped by the addition of four volumes of acetone and one volume of peroxide-free diethyl ether. The precipitated solids were removed by filtration, and the filtrate was evaporated under nitrogen at reduced pressure until substantially all volatile organic solvent had been removed. About 20 ml of aqueous solution, essentially free of organic solvent, remained. This solution was diluted to 100 ml with distilled water. [Pg.651]

Procedure (b). Prepare the indicator by dissolving 0.05 g bromopyrogallol red in 100 mL of 50 per cent ethanol, and a buffer solution by mixing 100 mL of 1M ammonium chloride solution with 100 mL of 1M aqueous ammonia solution. [Pg.327]

Procedure. Prepare an EGTA solution (0.05M) by dissolving 19.01 g in 100 mL sodium hydroxide solution (1M) and diluting to 1 L in a graduated flask with de-ionised water. Prepare the indicator by dissolving 0.065 g zincon in 2 mL sodium hydroxide solution (0.1M) and diluting to 100 mL with de-ionised water, and a buffer solution (pH 10) by dissolving 25 g sodium tetraborate, 3.5 g ammonium chloride, and 5.7 g sodium hydroxide in 1 L of de-ionised water. [Pg.332]

Prepare a stock solution of nitrobenzene by dissolving about 0.25 g (accurately weighed in a weighing bottle) in 50 mL of 95 per cent ethanol, and adding this to 450 mL of the buffer solution contained in a 500 mL graduated flask. Rinse the weighing bottle with two successive 5mL portions of 95 per cent ethanol and add each rinsing to the 500 mL flask finally make the flask up to the mark with buffer solution. [Pg.620]

Prepare a buffer solution (pH 4.5) by dissolving 6 g acetic (ethanoic) acid and 13,6 g sodium acetate in 1 L of distilled water. Pipette 10 mL of a commercial sample of citrus fruit juice into a 1 L graduated flask and make up to the mark with oxygen-free water,... [Pg.621]


See other pages where Buffer solutions with dissolved is mentioned: [Pg.815]    [Pg.815]    [Pg.515]    [Pg.268]    [Pg.432]    [Pg.311]    [Pg.819]    [Pg.222]    [Pg.47]    [Pg.50]    [Pg.213]    [Pg.266]    [Pg.327]    [Pg.96]    [Pg.1125]    [Pg.134]    [Pg.208]    [Pg.340]    [Pg.620]   
See also in sourсe #XX -- [ Pg.2 ]




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Buffer solutions

Buffer solutions with dissolved sodium citrate

Buffered solution

Dissolved solutes

Solutions dissolved solute

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