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Steel samples

Fig. 2. Typical rf signal from a 28 mm deep fatigue crack in 56 mm thick carbon steel sample... Fig. 2. Typical rf signal from a 28 mm deep fatigue crack in 56 mm thick carbon steel sample...
The concentration of Mn in steel can be determined by a neutron activation analysis using the method of external standards. A 1.000-g sample of an unknown steel sample and a 0.950-g sample of a standard steel known to contain 0.463% w/w Mn, are irradiated with neutrons in a nuclear reactor for 10 h. After a 40-min cooling period, the activities for gamma-ray emission were found to be 2542 cpm (counts per minute) for the unknown and 1984 cpm for the standard. What is the %w/w Mn in the unknown steel sample ... [Pg.646]

A class of analytical students is asked to analyze a steel sample to determine the %w/w Mn. (a) Given that the steel sample is 0.26% w/w Mn, estimate the expected relative standard deviation for the class results, (b) The actual results obtained by the students are... [Pg.703]

The experiment testing was realized on the steel samples having zinc coating. The samples were made of steel tape used for cables protection having surface density 100 and 200 g/nf, which corresponds to the thickness of zinc costing about 14 and 28 micrometers. The measurements on the base of the presented above procedure has given the thicknesses of 20 and 25 micrometers. [Pg.122]

Three factors influence the rate of corrosion of metals—moisture, type of pollutant, and temperature. A study by Hudson (1) confirms these three factors. Steel samples were exposed for 1 year at 20 locations throughout the world. Samples at dry or cold locations had the lowest rate of corrosion, samples in the tropics and marine environments were intermediate, and samples in polluted industrial locations had the highest rate of corrosion. Corrosion values at an industrial site in England were 100 times higher than those found in an arid African location. [Pg.126]

Griskin et reported that there is no apparent effect of steam pressure on the rate of oxidation of Cr-Ni steels at temperatures between 600°C and 650°C at 10.1-20.2 MPa. Similar observations for Cr-Mo and Cr-Mo-V steels between 500°C and 600°C have been made by Wiles" . She compared low-alloy steel samples exposed to 101 kPa steam with power plant components that had operated for up to 150000b in steam at 17.25 MPa and found no significant difference in the oxidation rates (Fig. 7.11). [Pg.987]

Steam condensate samples should be cooled in a stainless steel sample cooler. Samples should be run for 5 to 10 minutes before being collected in a 100-ml amber glass jar with a Teflon lid. The jar should be filled completely with no air space, but without over flowing. The cap should be tight, taped if necessary, and the sample kept cool prior to laboratory analysis. [Pg.534]

NIST s first four certified reference materials were steel samples, and these were followed by many others. The program supplied analytically well characterized homogeneous materials. This program included, from the beginning, homogeneity... [Pg.2]

This technique was subsequently modified for the determination of Co, Cu and Mn in pure iron and steel samples (Sommer and Ohls 1979). [Pg.142]

Baudoin etal. [168,169] first presented qualitative depth profiles of lacquer and polymer coatings by means of r.f. GD-OES. Quantitative depth profiles were successively obtained by Payling et al. [170] on prepainted metal coated steel. Samples comprised a (rutile) pigmented silicone-modified polyester topcoat over a polymer primer, on top of an aluminium-zinc-silicon alloy coated steel substrate. With GD-OES in r.f. mode, it was possible to determine the depth profile through the polymer topcoat, polymer primer coat, metal alloy coating, and alloy layer binding to the steel substrate with a total depth of 50 im, all in about 60 min on the one sample. GD-OES depth profiles of unexposed and weathered silicone-modified polyesters were also reported [171]. Radiofrequency GD-OES has further been used to... [Pg.619]

C. In a series of 29 steel samples, 12 were attacked while 17 were not... [Pg.33]

XPS was also used for the determination of chlorine in the passive film grown in chlorine containing electrolytes. While chlorine was found in the passive film on pure iron, it was absent for chromium rich stainless steel samples. Chloride content of the passive film is substantially time dependent, increasing with time until film breakdown occurs, and decreasing subsequently [109]. [Pg.119]

Occasional explosions experienced during use of hot perchloric acid to dissolve steel samples for analysis [1] were attributed to formation of hydrogen-perchloric... [Pg.1359]

Several authors observed CL emission based on reduction reactions. Lu et al. [59] developed a method by applying a Jones reductor for producing unstable reductants. A column (100 X 3 mm i.d.) filled with Zn-Hg particles was inserted into the flow stream of a flow injection system. CL was measured using a homemade CL analyzer. Although the Jones reductor was more effective for the species studied in 0.5-5 mol/L H2S04 solution, the authors found that a lower acid concentration improved the CL emission. Hie optimal pH was 6.5 for V(II), 2.5 for Mo(III), 3.5 for U(III), 3.0 for W(III), 3.0 for Cr(II), 2.5 for Ti(III), and 2.5 for Fe(II). The methods allowed determination of the above-mentioned species at pg/mL to ng/mL levels. It was assumed that the CL reactions were related to the production of superoxide radicals by dissolved oxygen in the solutions. The proposed methods could be successfully applied to the determination of V [60], Mo [61], and U [62] in water or steel samples. [Pg.128]

Two steel samples, dissolved in 50 cm3, each 1.000 g, gave the following absorbances ... [Pg.673]

It is veiy well known that in tropical climate there are two main seasons, rainy season and dry season. Under this conditions, the acceleration caused by chlorides should be higher in the dry season (winter period) and lower in the rainy season. As an example, on Table VII presents statistical parameters calculated for corrosion rate of steel at Viriato coastal stations for periods of six months corresponding to the wet season (may to October) and dry season (november to april). All steel samples were exposed for a six months period corresponding, starting on may or on november. Data correspond to the period may/1987 to November/1991. [Pg.85]

If a 1% solution of steel gave an absorbance of 0.36, what would be the concentration of nickel in the solution, and hence the steel sample as a w/w percentage ... [Pg.162]

In order to dissolve adequately all selenium species including selenium metal and selenium in steel samples, an aqua regia digestion procedure was used in lieu of the existing NIOSH extraction method. [Pg.108]

Bos et al. [94] compared the performance of ANNs for modelling the Cr-Ni-Fe system in quantitative XRF spectroscopy with the classical Rasberry-Heinrich model and a previously published method applying the linear learning machine in combination with singular value decomposition. They studied whether ANNs were able to model nonlinear relationships, and also their ability to handle non-ideal and noisy data. They used more than 100 steel samples with large variations in composition to calibrate the model. ANNs were found to be robust and to perform better than the other methods. [Pg.275]

Sampling is usually done by two persons, each equipped with a full-face mask and heavy rubber gloves. Connect to the unloading valve in the dome of the tank a stainless-steel sampling line with a 1-inch union and a 4-inch valve, and attach to the sampling line by a... [Pg.303]

The compound (8-10 g) was sealed in a stainless steel sample container with a Teflon gasket. The unit extended down from the manifold and, for temperatures up to 100°C, was immersed in a water bath regulated to 0.1 °C. Wnen higher temperatures were required, the sample container was inserted into a tube furnace regulated to 0.25°C. [Pg.321]

Simplified operating procedure For five minutes and under the same conditions in the reactor, a) a sample of the steel to be quantified in Cl, and b) a disc of filter paper onto which 100 pi of a solution of 0.1 g/1 of chloride ion had been previously adsorbed, (previously it had been verified that the filter paper contained no Cl), is irradiated. Then the steel sample is dissolved into solution by boiling with 40 ml of 2M HNO3 to which is added 2.00 g of dry KC1. This resulting solution is then introduced to 50 ml of an aqueous solution of 15% (w/v) AgN03. The AgCl precipitate is recovered, washed and then dried. The result of the count is displayed in the following table. [Pg.346]

We have observed such a transition in intact membranes of M. laidlawii which occurs at the same temperature as in the membrane lipids dispersed in water (77). Figure 11 shows representative endothermic transitions of membranes and lipids in water. Membranes were prepared for calorimetry by sedimenting at high speed, then 90-100 mg. of packed pellet were sealed in a stainless steel sample pan. The material was neither dried nor frozen before examination. Total membrane lipids were extracted with chloroform-methanol 2 1 v/v then dried and suspended in water. Lipids from the membranes of cells grown in the usual tryptose medium without added fatty acids are shown in a, while b and c are scans of intact membranes from the same cells. In b the membrane preparation had not been previously exposed to temperatures above 27 °C. The smaller transition at higher temperature probably arises from... [Pg.291]


See other pages where Steel samples is mentioned: [Pg.214]    [Pg.546]    [Pg.723]    [Pg.1856]    [Pg.149]    [Pg.390]    [Pg.237]    [Pg.423]    [Pg.1245]    [Pg.240]    [Pg.80]    [Pg.37]    [Pg.185]    [Pg.130]    [Pg.349]    [Pg.294]    [Pg.64]    [Pg.59]    [Pg.419]    [Pg.102]    [Pg.140]    [Pg.837]    [Pg.837]    [Pg.263]    [Pg.234]    [Pg.346]    [Pg.317]   


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