Investigation of Concretions from the Baltic Sea

The composition and specific features of the dissolution of iron manganese concretions from the Baltic Sea are investigated using an echelle spectrometer and atomic absorption spectrometry. The concretion samples used in the analysis are treated in diluted solutions of hydrochloric and nitric acids with additives of hydrogen peroxide. The as-analyzed ratio Mn : Fe in the samples studied is equal to 1.7, which is an important characteristic of the ratio of d elements involved in concretions from the Baltic Sea. The results of the investigations performed can be used to develop more efficient methods for selective extraction of manganese from similar concretions and to determine the isotope content in noble gases of ancient artifact origin that survive in concretions of the World Ocean.     

Check of the reliability of concrete dams during their construction and operation

Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 7, pp. 43–46, July, 1990.     

The role of proto-oncogenes in normal hemopoiesis and the genesis of leukosis

Results of investigations on the role of protooncogenes in the regulation of proliferation and differentiation of normal hemopoietic cells and in the pathogenesis of tumoral hemopoietic diseases are reviewed. The ways of the protooncogene activation in leukemias are discussed.     

Improved Accuracy in Measuring Two-Terminal Network Parameters

A method is given for raising the accuracy in determining the parameters of a two-terminal network by the substitution method, which employs a personal computer and measurements with digital voltmeter and phasemeter. Results are given for three-component one-port networks.     

Structure and Properties of Low-Alloy High-Nitrogen Martensitic Steels

Special features of structure formation and mechanical properties of low-alloy martensitic steels with superequilibrium content of nitrogen and low content of carbon are considered. Experimental data on the effect of the temperature of heating for hardening and tempering on the structure, strength, and ductility of these steels are presented. The advantages and disadvantages of the introduction of nitrogen into low-alloy martensitic steels instead of carbon are discussed. It is shown that steel 10Kh3A combines high strength with high ductility. This steel is considered as a material for heavily loaded parts and nonwelded structures instead of high-strength steels alloyed with Ni, Mo, V and other expensive and scarce elements.     

The use of an integrating coincidence γ-spectrometer for analyzing a mixture of radioactive isotopes

The integrated -coincidence method is used for the selective detection of radioactive isotopes emitting cascade -quanta. This method enables the quantitative content of the isotopes to be determined, whose -radiation comprises 3–4% of the -radiatlon from the mixture, and also to be determined the quantitative content of the radioactive isotopes whose decay is accompanied by the emission of a positron, with subsequent emission of a -quantum.Translated from Atomnaya Énergiya, Vol. 19, No. 4, pp. 342–346, October, 1965     

On the structure and properties of high-nitrogen low-carbon non-austenitic steels

Phase transformations, when cooling and heating non-austenitic high-nitrogen low-carbon steels containing chromium and other alloying elements, as well as structure and mechanical properties of these steels were analyzed. It was confirmed that these steels have high temperature chromium diffusion controlled pearlitic type transformation and martensitic type transformation. Experimental high nitrogen steels after quenching and tempering provide mechanical properties of about the same level as high strength commercial alloyed steels. Features of nitrogen as an alloying element in steels discussed allow the supposition of a possible reduction of the consumption of nickel, manganese, molybdenum or tungsten in high strength alloyed steels.