INVESTIGATION OF THE ECOLOGICAL PROBLEMS OF AMMUNITION UTILIZATION AND THE DEVELOPMENT OF THE CATALYTIC METHOD TO PURIFY THE EMISSIONS FROM ITS THERMAL TREATMENT

Modern methods of chemical-thermal treatment (CTT) such as cyanidation, nitrogen casehardening and others are widelyused in different branches of industry and they are processes promising enough. The solution of ecological problems of diffusion strengthening and improvement of performance attributes of a surface layer are interrelated with the use of special powder mixtures – lutes, pastes, called saturating environment (carburizer). As a saturating environment in the work there is used a nitrogen-carbon paste on the basis of fine gas black (amorphous carbon ~ 60%) and iron sinergisty potassium ~ 40% with the addition of carbamide (urea) as a nitrogen-containing component. A saturating pasty environment on the basis of soot with nitrogen-containing admixtures (urea and iron sinergisty potassium) is efficient for the surface strengthening treatment of steel products in a wide range of temperatures. Solid carbonitrides arising on the surface of products processed in this environment promote the increase of their wear-resistance and other performance attributes. A carbonitride edge on the surface of steel (20…30) ChGT arising at nitrogen case-hardening in a paste-type carburizer does not decrease wear-resistance, but, at the same time increases working capacity of parts and units and material fatigue resistance.

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Pollutant Identification by Selected Area Electron Diffraction

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052675 ◽

1974 ◽

Vol 32 ◽

pp. 532-533

Author(s):

R. E. Ferrell ◽

G. G. Paulson ◽

C. W. Walker

Keyword(s):

Thermal Treatment ◽

Electron Diffraction ◽

Sample Preparation ◽

Crystal Structures ◽

Water Samples ◽

Environmental Samples ◽

Short Review ◽

Selected Area Electron Diffraction ◽

Multiple Component

Selected area electron diffraction (SAD) has been used successfully to determine crystal structures, identify traces of minerals in rocks, and characterize the phases formed during thermal treatment of micron-sized particles. There is an increased interest in the method because it has the potential capability of identifying micron-sized pollutants in air and water samples. This paper is a short review of the theory behind SAD and a discussion of the sample preparation employed for the analysis of multiple component environmental samples.

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Development of Crystallinity in Turbostratic Boron Nitride Derived from Polymeric Precursors

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100089081 ◽

1991 ◽

Vol 49 ◽

pp. 954-955

Author(s):

X. Qiu ◽

A. K. Datye ◽

T. T. Borek ◽

R. T. Paine

Keyword(s):

Thermal Treatment ◽

Boron Nitride ◽

Diffraction Pattern ◽

Polymeric Precursors ◽

Polymer Precursors ◽

Diffuse Ring

Boron nitride derived from polymer precursors is of great interest for applications such as fibers, coatings and novel forms such as aerogels. The BN is prepared by the polymerization of functionalized borazine and thermal treatment in nitrogen at 1200°C. The BN powders obtained by this route are invariably trubostratic wherein the sheets of hexagonal BN are randomly oriented to yield the so-called turbostratic modification. Fib 1a and 1b show images of BN powder with the corresponding diffraction pattern in fig. 1c. The (0002) reflection from BN is seen as a diffuse ring with occational spots that come from crystals of BN such as those shown in fig. 1b. The (0002) lattice fringes of BN seen in these powders are the most characteristic indication of the crystallinity of the BN.

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