Anion standard

Fig. 4. Analysis of an anion standard solution by IC (a) and CE (b) [48]. IC conditions aVydac 302IC4.6 column, a flow-rate of 2.5 ml/min, an injection volume of 25 xl, an isophthalic acid mobile phase, UV detection at 280 nm. CE conditions an electrolyte of potassium dichromate, sodium tetraborate, boric acid and the DETA (diethylenetriamine) EOF modifier, pH 7.8 65 cmX75 xm I.D. capillary 20 kV indirect UV detection at 280 nm. Anions 1, chloride 2, nitrite 3, chlorate 4, nitrate 5, sulfate 6, thiocyanate 7, perchlorate 8, bromide.

Fig. 2.23 shows the separation achieved on a 12 anion standard by this procedure. Sulphide, cyanide, bromide, and sulphite are detected at the silver electrode while nitrite, nitrate, phosphate and sulphate produce no response. Due to the low dissociation of hydrogen sulphide and hydrogen cyanide following protonation by the suppressor column, they are not detected by the conductivity detector. 

Fig. 5 Electropherogram of a mixed anion standard. Hydro-dynamic injection (15 cm, 120 sec, 39.1 nL) with sodium borate buffer at pH 8. Peak 1 3.2 ppm selenate peak 2 3.6 ppm selenite peak 3 1.9 ppm arenate peak 4 4.4 ppm DMA peak 5 4.7 ppm arsenite. (Reproduced from Ref. [19] with permission of Elsevier Science, copyright 1998.)...

Fig. 3-2. Variation of the retention of bromide and nitrate with temperature. — Separator IonPac AS3 eluent 0.0028 mol/L NaHC03 + 0.0022 mol/L Na2C03 flow rate 2.3 mL/min detection suppressed conductivity injection volume 50 pL anion standard.

Fig. 3-57. Separation of inorganic anions using NaOH as the eluent. — Separator column Ion-Pac AS3 eluent 0.001 mol/L NaOH flow rate 2.3 mL/min detection suppressed conductivity injection 50 pL anion standard solution.

Fig. 3-58. Dependence of the retention of various inorganic anions as a function of eluent pH after adjustment via different carbonate/bicarbonate concentrations. - Separator column IonPac AS4 flow rate 2 mL/min detection suppressed conductivity injection 50 pL anion standard.

Fig. 3-61. Separation of inorganic anions using a borate/gluconate buffer as the eluent. - Separator column TSK Gel IC-PW eluent 0.0013 mol/L Na2B407 + 0.0058 mol/L H3B03 + 0.0014 mol/L potassium gluconate/acetonitrile (88 12 v/ v), pH 8.5 flow rate 1.2 mL/min detection direct conductivity injection 100 pL anion standard (5 to 40 ppm) (taken from [66]).

Ionisation constants of vitisin A and the various ethyl-linked malvidin-3-glucose / catechin / epicatechin dimers were determined by high voltage paper electrophoresis (HVPE) using chromatography paper (Chr. 1,. Whatman, England) as previously reported (28). All relative mobilities (Rm) were compared to anionic standards orange G and xylene cyanol. Fructose was used as... 

Figure E33-2. Anion standards for engine coolant analysis.

Figure 12.5 Separation of a seven-anion standard with single-column ion chromatography. Column [Chromatographic conditions IC-Pak Anion HR, 4.6 mmx7S mm. Waters Corp. Eluent borate/gluconate. Sample seven-anion standard (1) fluoride (2) bicarbonate (3) chloride (4) nitrite (S) bromide (6) nitrate (7) phosplmt (8) suUite. Detection conductivity. (Qiromatogram courtesy of Waters Corp.)...

The determination of the unreacted metal ion used as the precipitation reagent, in the supernatant solution, is more often employed than the determination of the precipitated metal after dissolution of the precipitate, as less manipulation is required. Calibration solutions are generally prepared from the anion standard solutions treated in the same way as the sample solutions. 

Pipette 10 ml of mixed anion standard solution I into a 100-ml measuring flask and make up to the mark with water. 

Figure 2 The effect of carbonate on the separation of common anions. (A) anion standards with 60nmi COi (B) without...

PMTh-, PANI-, aud PPy-modified electrodes includiug different anions Standard solutions Discrimination between soluticms containing chemical species representative of different tastes sweet, bitter, acid, salty, and astringcmt PCA [130]... 

Figure 3.136 Dependence of the retention of 2.8 mmol/L NaHCOa + 2.2 mmol/L Na2C03, pH various inorganic anions on the pH value of adjusted with HaBOa/NaOH flow rate 2 mL/min the buffer mixture at constant ionic strength, detection suppressed conductivity injection Separator column lonPac AS4-SC eluent volume 50 pL sample anion standard.

Figure 3.137 Effect of ionic strength on the retention behavior of various inorganic anions at constant pH value. Separator column lonPac AS4-SC flow rate 2ml7min detection suppressed conductivity injection volume 50 pL sample anion standard.

Figure 10.203 Isocratic analysis of monofluor-ophosphate in toothpaste. Separator column lonPac ASH eluent 2.5mmol/L NaHC03 + 2 mmol/L Na2C03 flow rate 1 mL/min detection suppressed conductivity injection volume lOpL peaks in the anion standard ...

Fig. 3-38. Fast gradient separation of minerai acids on lonPac ASH. - Eluant (A) water, (B) 0.1 moi/L NaOH gradient 5% B isocratically for 3 min, then iineariy to 45% B in 8 min flow rate 2 mL/min detection suppressed conductivity injection 25 pL anion standard with 2.5 mg/L fluoride (1). 5 mg/L each of chloride (2) and nitrite (3), 10 mg/L orthophosphate (4), 10 mg/L bromide (5), 10 mg/L nitrate (6), and 5 mg/L sulfate (7).

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