INSTRUMENTATION
Harleco
®
INDUSTRIAL REAGENTS 2106 BUFFER REFER-32 oz. 2.5 gal. ENCE SOLU TION—pH 4.01 ± .01 @ 25°C 4.95 17.60 Potassium hydrogen phthalate solution. Includes N.B.S. temperature coefficient 0° t o 6 0 ° C 21131 BUFFER REFER- 32 oz. 2.5 sal. ENCE SOLU TION—pH 7.00 ± .01 @ 25°C 4.95 17.60 Potassium and sodium phosphate solution. 2119 BUFFER REFER- 32 oz. 2.5 sal. ENCE SOLU TION—PH 10.00 ± .01 @ 25°C 4.95 17.60 Boric acid-potassium hydroxide solution. 1306c S O D I U M ΗΎ- 32 oz. 2.5 gal. DROXIDE— N / 1 0 Solution.. 2.45 13.20 1306d S O D I U M HY32 oz. 2.5 sal. DROXIDE— Normal Solution. 2.45 13.20 *3786 KARL FISCHER 16 oz. 32 oz. REAGENT— Stabilized Single
5 gal.
22.00
5 gal.
1248a
1248d
*2038 *1258
*1256
2830
2832 2005
20052
*1895
*64094
*U.S. Postal Ruling.
5 sal.
22.00 5 gal. 19.25 5 gal. 19.25 gallon
Not permitted in mails.
For a complete listing of Harleco Industrial Reagents, please write for publication number 6 2 3 .
/fet/le»® 60TH & WOODLAND AVENUE PHILADELPHIA, PENNSYLVANIA 19143 Circle No. 115 on Readers' Service Card 86 A
·
ANALYTICAL CHEMISTRY
10
22.00
29.10 Case-4 X 1 gal. bottles 98.00 107.80 KARL FISCHER 32 oz. 2.5 gal. 5 sal. REAGENT WATER STAN DARD—Meth anol 3.65 15.95 28.35 1 ml. => 1 mg. H2O ± 0.01 π s. HYDRO32 oz. 2.5 gal. 5 sal. CHLORIC ACID—N/10 Solution 2.45 13.20 19.25 HYDRO32 oz. 2.5 gal. 5 gal. CHLORIC ACID—Normal Solution 2.45 13.20 19.25 DICHROMATE gallon 2.5 gal. 5 gal. CLEANING SOLUTION 6.40 10.75 21.75 IODINE16 oz. 32 oz. gallon MONOCHLORIDE—Wijs 26.65 IODINE16 oz. 32 oz. gallon BROMINE— Hanus SolutionA.O.A.C 5.05 8.65 31.30 SILVER NI32 oz. 2.5 sal. 5 gal. TRATE—1 ml. = 1 mg. NaCI 2.65 14.30 21.45 SILVER Nl32 oz. 2.5 sal. 5 gal. TRATE—1 ml. = 1 mg. CI 2.65 15.15 27.50 EDTA—Dl. 32 oz. 2.5 gal. 5 sal. SODIUM SOLUTION— 1 ml. = 1 mg. CaCOî 2 40 9.35 16.50 Contains magnesium. Diehl, Goetz and Hach. EDTA—Dl32 oz. 2.5 sal. 5 sal. SODIUM SOLUTION— 1 ml. = 1 mg. CaCOs 2.90 12.65 21.75 Without masnesium. Betz and Noll. NESSLER RE32 oz. 2.5 sal. 5 gal. AGENT— A . P . H . A . Speci97.35 NESSLER unit COMPOUND— (Dry) A . P . H . A 5.80 Sufficient for 1000 ml. solution Compound contains required alkali.
*1849
%A
Figure 2. Correction necessitated by matrix influences is shown above. Upper curve is that of a single channel for Cu; lower curve represents improvement in curve by use of Ag nonabsorbing line for correction
multaneously in each channel. Perturbations in the flame cause exactly similar variations of absorption signals both in time and magnitude for both resonance lines of the same element. Accordingly, a ratio of the measurements provides correction for flame noise. In Figure 3, for the purpose of demonstration, flame noise was purposely magnified by reducing the sample aspiration rate from 6 ml per minute to 0.3 ml/min thus reducing sensitivity 20-fold but simultaneously increasing the sensitivity by a 20-fold scale expansion. The signal at the left is for single channel recording. On the right, the recording is the ratio of absorbance by the two Ou lines. There are six ways to use the JarrellAsh fully compensated atomic absorption unit. 1. As two independent channels for atomic absorption with each set for the analysis of a different element. The operator may choose to read the two channels sequentially on a recorder or print-out system by punching a single button, or may elect to read both channels separately on command. When a twin-channel recorder is available, the signals may be displayed simultaneously. 2. As a unit with one channel operated in atomic absorption and the other channel, simultaneously, in flame emission. 3. As an analytical system compensating for interferences caused by the matrix. One channel is tuned to the absorbing wavelength for the element and the other channel to a nearby wavelength which is not capable of being selectively absorbed by atoms of the
Cu
3247-
Cu 3 2 7 4
( 3ppml
0.3 ml/ min (20 X S E ) Single Chonnel Cu
3247
Rotlo Cu 3 2 4 7 / Cu 3274
J»
Figure 3. Flame noise suppression is achieved by the Curry two-line method. A ratio of measurements provides correction as shown above
element being analyzed. The normal mode of readout is the ratio of the two signals and actuation of a button displays the value. The operator may also elect as an alternative to observe the independent signal in each channel. 4. As an analytical system correcting for noise produced in the flame, by the Curry two-line method. Each of the two channels is tuned to a differing absorbing line of the same element. The same flame noise occurs in each channel and the noise values cancel each other when the ratio of the signals is displayed. This operation permits a determination to be made with as little as 20 microliters of sample soultion. 5. The instrument may be used to give the ratio signal for two separate elements when one is present in a known concentration and is employed as an internal standard for the other.
