Research of Dysprosium, Terbium and Neodymium Oxides Fluoration

2016 ◽  
Vol 683 ◽  
pp. 345-352 ◽  
Author(s):  
Vladimir Sofronov ◽  
Zakhar Ivanov ◽  
Yuriy Makaseyev ◽  
Tamara Kostareva

Production of high energy permanent magnets (HEPM) on the basis of rare-earth metals is one of leading knowledge intensive branches of world industry. Raw materials for production of magnets are magnetic alloys. In order to increase magnetic features scientists implement the additives of certain metals and their compounds, such as dysprosium and terbium additives in substantial amounts – up to 7-8 %.Within the framework of a ladle fluoride technology of HEPM manufacturing on the basis of a system Nd-Fe-B, developed by authors, scientists implement the additives of dysprosium and terbium fluoride, by virtue where of there was conducted a research on fluoration kinetics of corresponding oxides by elemental fluorine. The present article quotes results of such research and defines main kinetic parameters of examined processes – diffusion coefficient, kinetic constant and activation energy. Aiming to cost reduction of fluoride manufacture ammonium fluoride was used as a fluorinating agent by the example of fluoration of neodymium oxide.

Author(s):  
N. I. Chernova ◽  
S. V. Kiseleva ◽  
O. M. Larina ◽  
G. A. Sytchev

Algae biomass is considered as an alternative raw material for the production of biofuels. The search for new types of raw materials, including high-energy types of microalgae, remains relevant, since the share of motor fuels in the structure of the global fuel and energy balance remains consistently high (about 35%), and the price of oil is characterized by high volatility. The authors have considered the advantages of microalgae as sources of raw materials for fuel production. Biochemical and thermochemical conversion are proposed as technologies for their processing. This paper presents the results of the study of the pyrolysis of the biomass of clonal culture of blue-green microalgae / cyanobacteriumArthrospira platensis rsemsu 1/02-Pfrom the collection of the Research Laboratory of Renewable Energy Sources of the Lomonosov Moscow State University. An experiment to study the process of pyrolysis of microalgae biomass was carried out at the experimental facility of the Institute of High Temperatures RAS in pure nitrogen grade 6.0 to create an oxygen-free environment with a linear heating rate of 10 ºС / min from room temperature to 1000 ºС. The whole process of pyrolysis proceeded in the field of endothermy. The specific amounts of solid residue, pyrolysis liquid and gaseous products were experimentally determined. As a result of the pyrolysis of microalgae biomass weighing 15 g, the following products were obtained: 1) coal has the mass of the solid residue is 2.68 g, or 17.7% of the initial mass of the microalgae (while 9.3% of the initial mass of the microalgae remained in the reactor); 2) pyrolysis liquid – weight 3.3 g, or 21.9% of the initial weight; 3) non-condensable pyrolysis gases – weight 1.15 l. The specific volumetric gas yield (the amount of gas released from 1 kg of the starting material) was 0.076 Nm3/ kg. The analysis of the composition and specific volume yield of non-condensable pyrolysis gases formed in the process of pyrolysis, depending on temperature. It is shown that with increasing temperature, the proportion of highcalorie components of the gas mixture (hydrogen, methane and carbon monoxide) increases. The calorific value of the mixture of these gases has been estimated.


Author(s):  
Lina Yurievna Lagutkina

The author of the article discloses the prospects of development of the world feed production for aquaculture based on the analysis of key innovative technological and market trends. The author specifies that shortage, high cost, low ecological compatibility of traditional raw materials - fish flour - are among major limiting factors in the development of production of feeds for aquaculture. This fact, in turn, limits sustainable development of aquaculture both in Russia, and in the world in general. The article presents the overview of a current status of the world industry of feed production in aquaculture, where the regional situation is studied, as well. For the first time, there is given the outlook of innovative technologies in feed production based on the alternative sources of protein (on the example of projects of leading aquabiotechnological companies) which will determine industry’s objectives for the mid-term perspective.


1995 ◽  
Vol 400 ◽  
Author(s):  
S. Bellini ◽  
G. Mazzone ◽  
A. Montone ◽  
M. Vittori-antisari Enea ◽  
C.R. Casaccia

AbstractThe diffusion properties of a Ni-Zr metallic glass formed at the interface of a bulk diffusion couple have been studied in conditions far from a fully relaxed state. The growth kinetics of the interface film have been enhanced by both plastic deformation and high energy electron irradiation. Different results have been obtained in the two cases, since in the first case the film grows exponentially with time, while in the second case the usual square root dependence on time is observed. This behaviour has been interpreted as a consequence of the annihilation kinetics of the excess free volume introduced in the glass by the above methods. Two different mechanisms of free volume annihilation , namely exchange with a crystal vacancy at the glass-crystal interface and structural relaxation in the bulk glassy phase have been considered to be operative so that the nature of the growth kinetics has been found to depend on the mechanism predominant in each experimental condition.


2009 ◽  
Vol 147-149 ◽  
pp. 290-295 ◽  
Author(s):  
Bogdan Broel-Plater ◽  
Stefan Domek ◽  
Arkadiusz Parus

The paper deals with semi-active chatter absorber based on an electrodynamic transducer built around high-energy permanent magnets. Also, a fuzzy logic control system for the absorber control system has been designed. The principal advantage of fuzzy control is the possibility to implement practical experience gained by machine operators in the control algorithm. Hence, the possibility of factoring such quantities, as vibrations experienced by selected points of the machine-tool, and sound emitted by working machine into the analyzed chatter absorber fuzzy control system has been studied in the paper. The control system has been tested by way of simulation with the use of the process and cutting force models.


2014 ◽  
Vol 51 (1) ◽  
pp. 21-31 ◽  
Author(s):  
A. Serebryakov ◽  
N. Levin ◽  
A. Sokolov ◽  
E. Kamolins

Abstract Application of wind generators opens wide possibilities for raising the efficiency of low- and medium-power wind generators (WGs). The mass of generators in the proposed version is smaller, their reliability higher, while maintenance costs are lower. At the same time, the use of high-energy permanent magnets in generators of enhanced power comes up against some obstacles, which can be overcome through proper orientation of magnetization at creation of a magnetic field in the airgap of electrical machine. In this regard, it might be preferable to use magnets with indirect action on the airgap instead of those with direct action. A convincing example of the former variant is a generator with tangentially oriented magnetization of permanent magnets. In the work, an attempt is done to prove the advantages of such installation in modern low- and medium-power WGs


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