Rapid Determination of Chromium by Differential Spectrophotometry

The differential spectrophotometric method was applied to the determination of chromium in ferrochromium and high chromium alloys. Chromium was analysed by reading the absorbance of chromium (VI) in 1N perchloric acid at 350 mμ against the reference solution containing 16.0 mg chromium per 100 ml. The common alloying elements, iron, nickel and manganese, did not interfere up to about 50 per cent concentration. However, when samples contained over 50 per cent iron, iron was removed by solvent extraction from hydrochloric acid solution. Similarly, titanium and cobalt did not interfere up to 20 per cent concentration

A New Method of Spectrophotometric Determination of Tin with Alizarin Blue : Application of this Method for the Estimation of Tin in Steel and Nonferrous Alloys

A new spectrophotometric determination of tin was investigated. Stannic ion formed a colored complex compound with alizarin blue in 1 N-hydrochloric acid solution and was extracted by the mixed solution of cyclohexanone and ethyl acetate. The absorption spectrum of this complex had a maximum absorption at the wave length of 580 mμ, and its molecular absorption coefficient was 9.5×10^3. This reaction was also applied to the determination of tin in steel after separating it with hydrogen sulfide. Similarly, 0001～0.1 per cent of tin in nonferrous alloys was analyzed after being separated by co-precipitation with manganese dioxide

Spectral Analysis by Low-Voltage Impulse Discharge. An Indirect Excitation Procedure

An indirect procedure for the spectrometric excitation by a low voltage impulse discharge was studied. In this procedure the collision of excited atmosphere gas with the target materials caused the emission of the spectra of the target element. Nitrogen atmosphere and carbon auxiliary electrodes were found to be suitable and comparatively high intensity spectra could be obtained for magnesium, tin, lead and titanium. It has also been found that an application of this excitation procedure to non-conductive materials was effective

Analysis of Alloys by Fluorescent X-Ray Spectroscopy Non-Destructive-Addition Method

In order to determine metal samples rapidly and with a few standard samples, a new method, non-destructive-addition method was proposed. As theoretical equations for this method, the following equations were introduced : x=a(I_M/I_a-1)/I_M/I_x・(1-a)+I_M/I_aa-1 where x is the weight fraction of the element to be analyzed in the unknown smaple and I_x is X-ray intensity of it, a is the weight fraction of the element to be analyzed in the standard sample and I_a is the X-ray intensity of it. I_M is the X-ray intensity of the pure metals of the element to be analyzed ; and I_M/I_M\u27・W_m\u27/W_m-1/W_m\u27-W_m=I_M/I_M\u27・W_m\u27\u27/W_m-1/W\u27\u27_m-W_m where W_m and W_m\u27 are weight fraction of the element to be analyzed in the standards and I_M, I_M\u27 are the X-ray intensity of them, W_M" is the weight fraction of the element to be analyzed in the unknown sample and I_m" is the X-ray intensity of it. After preliminary experiments on some powdered samples, these equations were applied to the determination of some metals, for example nickel, chromium or manganese in steels. Satisfactory results were obtained

Enrichment Procedures for Small Quantities of Metals by Organometallic and Other Coprecipitation Techniques for X-Ray Fluorescence Analysis

Enrichment procedures for small quantities of metals by organometallic and other coprecipitation techniques for X-ray fluorescence analysis were studied. In order to obtain a higher X-ray intensity and good reproducibility in the measurements, five requirements were considered for the precipitants and for the precipitate. Favourable organic precipitants are mainly alizarine blue, phenyl fluorone, and cupferron. Good inorganic precipitates were fluorides and reduced metals. Other precipitation procedures can be applied to some metal elements, if the precipitation reaction is selective and a higher X-ray intensity is obtained

On the Unusual Fluorescence X-Ray Intensity Variation in Some Aluminium and Magnesium Alloys

The unusual fluorescence X-ray intensity variation in some aluminiun and magnesium alloys was investigated. It was confirmed that the phenomenon occurred when the primary crystals having differences in mass absorption coefficients for the fluorescence X-ray of the elements to be analyzed precipitate on both sides of the eutectic point. A simple model of an eutectic alloy was employed for the calculation. The phenomenon should be considered in the fluorescence X-ray analysis of alloys such as silicon in silmine, aluminium in alnico and others

Determination of Alloyed Elements in Special Steels by X-Ray Fluorescent Spectroscopy. I : Nickel and Chromium in Nickel-Chromium Steel and Tungsten in Tungsten Steel

In order to analyze alloyed elements in some special steels, a calibration curve method was examined, in which the metal of the window of sample holder was used as the compensative reference. This method was recognized to be simpler and more suitable than other method for rapid analysis. Further, the influence of diverse elements on the result was considered in a binary system

Determination of Alloyed Elements in Special Steels by X-Ray Fluorescent Spectroscopy. II : Influence of Diverse Elements

A semiquantitative method of estimating the influences of various elements in the samples was examined. This method was based on the application of the equation. I_=K_W_a/Σ_bW_b (μ_b/ρ_b), which was used by E.N. Davis and which could also be derived from Beattie-Brissey\u27s or from other\u27s approximate equation

A New Method of Spectrophotometric Determination of Zinc with Alizarin Blue : Application to Estimation of Zinc in Tin and Lead

Alizarin blue combining with zinc formed a colored complex at pH 5.6, and was extracted from aqueous phase by using a mixture of cyclohexanone and ethyl acetate. This complex had a maximum absorption at 635 mμ, the molecular absorption coefficient being 2.69×10^4. After the interference of several cations and anions were examined, microquantities of zinc in tin and lead were successfully determined by this method

A New Spectrophotometric Determination of Small Amounts of Titanium in Steel and Ferroalloys. I : Determination of Titanium in Steel and Cast Iron

A new spectrophotometric method of using sodium alizarin-sulfonate^ was applied to the determination of a small amount of titanium in steel and cast iron. Such a separation of iron as in the case of hydrogen peroxide method was unnecessary, and 0.2～0.002 per cent of titanium in some steels and cast iron was determined without any separation of iron. When sample contained much chromium as in high chromium steel, it was separated briefly with mercury cathode electrolysis