Articles

In the heaviest fractions such as resins and asphaltenes (see article 1.2), metal atoms such as nickel and vanadium are found. They belong in part to molecules in the porphyrine family where the basic pattern is represented by four pyrrolic rings, the metal being at the center of this complex in the form Wi - or V0+ (< 3)... 

This technique is used to quantify one or more components in a mixture, i.e., extracting them from mixtures to facilitate their final analysis. An example is that for the asphaltenes, already described in the definition of these components in article 1,2.1. 

Absorption is related to concentration by the Beer-Lambert relation which we will examine further in article 3.2.2.1. 

Analysis of such cuts by spectrometry requires a preliminary separation by chemical constituents. The separation is generally done by liquid phase chromatography described in article 3.3.5. 

Interest in this method has decreased since advances made in gas chromatography using high-resolution capillary columns (see article 3.3.3.) now enable complete identification by individual chemical component with equipment less expensive than mass spectrometry. 

Correlations have been found between certain absorption patterns in the infrared and the concentrations of aromatic and paraffinic carbons given by the ndA/method (see article 3.1.3.). The absorptions at 1600 cm due to vibrations of valence electrons in carbon-carbon bonds in aromatic rings and at 720 cm (see the spectrum in Figure 3.8) due to paraffinic chain deformations are directly related to the aromatic and paraffinic carbon concentrations, respectively. )... 

On leaving the column, the components enter a plasma functioning in identical manner to that described in article 2.2.6.3. All the atoms present emit their own specific emission spectra and can be detected and quantified. The sensitivity is excellent for carbon, hydrogen, and sulfur and average for nitrogen and oxygen. 

When the boiling point is measured at a pressure other than normal atmospheric, the normal boiling point can be calculated by a method described in article 4.1.3.4. 

Cutting petroleum into fractions is done by the method illustrated in Figure 4.2. The petroleum fractions should correspond to the characteristics described in article 4.1.2. If certain characteristics are estimated, it is mandatory to compare the calculational results with the properties of the cuts and to readjust the estimated characteristics. 

If the vapor pressure is of interest, the acentric factor is calculated by the Lee and Kesler formula or by the Soave method, which are given in article 4.5.2. 

To calculate the heat of vaporization, the Lee and Kesler method in article 4.3.1.3 is used. 

The coefficients B and Tq are obtained either by smoothing the experimental viscosity data, or by Van Velzen s method of contributing groups (see article 4.1.1.2). 

The Lee and Kesler method for calculating densities is given in article 4.3.1.1 its average accuracy is about 1%, when the pressure is less than 100 bar. 

The conductivity of a real gas can be calculated by the Stiel and Thodos method, already used for liquids and given in article 4.3.2.2.a ... 

The curve obtained can be transformed into a curve at a different pressure by the equations of Maxwell and Bonnel (see article 4.5.3.2.c). 

The introduction of monomers containing polar groups such as tertiary amines, imidazoles, pyrrolidones, pyridines, etc., gives the polymer dispersant properties that will be discussed in the article on dispersant additives for lubricants. 

ASME Code, Article II, Subsection A, Section V, Boiler and Pressure Vessel Code, 1983. 

A study is at present being carried out to check and validate the feasability of acoustic emission monitoring of the pneumatic testing of tanks. This study is being carried out in the context of the CIAPES program. This article gives only a brief summary of the results obtained on various materials, and different types of vessels, under different operating conditions. 

Tensor Field Tomography for Residual Stress Measurement in Class Articles. 

Many authors have shown that residual stresses in glass articles can be formally considered as the thermal stresses due to a certain fictitious temperature field. In the general case... 

In this article, we are contented to quote only the theoretical principle, the development and the implantation will make the object of future works. 

Article is denoted to the investigation and the creation of the new ultrasonic and information technologies (IT) and the technical methods of non-destructive evaluation (NDE) of material state in the product, which are based on principles of ultrasonic computing tomography (USCT). These results concern two important questions ... 

This article presents methods of synthesis and objective control of special flat optical elements (computer-synthesized holograms) as elements of protection. Due to the limited number of pages, we cannot go into great detail to explain the technology of how computer-synthesized holograms are created. The goal of this publication is to discuss following subjects ... 

The 16-bit and 32-bit software for eddy current testing using PC measurement cards manufactured by SOFRATEST, France, is presented in this article. Microsoft Visual C/C++ Development System and Tools have been used. 

During many years in Scientific Research Institutes of Nuclear Physics and Introscopy at Tomsk Polytechnical University (TPU) researches into induction electron accelerators and their uses for non-destructive radiation quality control of materials and articles have been conducted. Control sensitivity and efficiency detection experimental researches have been conducted with the high-current stereo-betatron modifications [1], and KBC-25 M and BC-50 high-current betatrons [2,3] in range of 11 MeV and 25-50 MeV radiation energy. 

Induction electron accelerators - betatrons- are widely used as radiation sources in industrial flaw detection of materials and articles of high thickness. However, relatively low radiation intensity has become the barrier for the most wider betatron use in this area. For the efficiencyincrease of radiation control method of articles, as well as for the possibility to control materials and articles of the most thickness the significant increase of betatron radiation intensity has been required. 

High-current betatrons experiments confirm the wide practical possibilities of use of these installations for radiative control of the articles and materials with big thickness. 

In world practice RCT application is considered to the decision of control of the high density objects. The particular feature of RCT is the possibility of the reception of the quantitative information. Besides, the absence of characteristic to X-ray CT result distortions, which are caused by variation of an average value of polychromatic radiation energy, when it passes through an article, promotes the increase of accuracy characteristics of radionuclide CT... 

The AC-3 common industrial radionuclide tomograph have following technical characteristics diameter of tested articles from 5 to 250 mm, time of information registering -5-25 min, spatial resolution - 1%/... 

We are sure that with this system we have developed a powerful tool to eliminate the shortcomings of manual inspection as discussed in the beginning of the article. We are also sure that this automatised test is not suitable in all applications. However, where there are many details to be tested and where these can be handled automatically, we think AMPl may be a competetive alternative which improves both the quality of inspection and the working environment. 

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