Vladimir Vasil'evich Lapin (on the occasion of his 80th birthday)
Post on 11-Jul-2016
sintering rate are increased. The maximum compaction of the specimens is observed at 1500~
With an increase in the isothermal dwell, the amount of liquid phase and the degree of compaction of the specimens are increased. Moreover, the degree of compaction is also affected by the form of the added g lass- forming mater ia l . Additives containing a liquid phase of the composit ion CaO--B203--SiO 2 have a more intense effect on the activity of the sintering process. Thus, 5% of this additive has exactly the same effect on the sintering of the specimens as 10% of an additive of the composit ion CaO--A1203--SiO 2. Thus, the amount of added mater ia l has a significant effect on the propert ies of the final mater ial .
These studies showed that the most significant effect on the sintering is obtained from the addition of composit ion Bs.
The values of the kinetic constant K and of the power n character iz ing the rate of isothermal shrinkage (Table 2) were found from the exper imental kinetic curves. F igure 3 shows the graph of log K = f(1/T). The relat ive values of the activation energies found from this dependence indicate that the main sintering mechanism of these part icular specimens is bulk diffusion and the greatest effectiveness of the additives from the CaO--B203--SiO 2 system in the sintering of alumina ceramics is confirmed.
L ITERATURE C ITED
T. Miter, D. Georgiev, and G. Iordanov, Structural Materials and the Silicate Industry [in Russian], No. 3 (1978).
VLADIMIR VAS IL 'EV ICH LAP IN (ON THE OCCASION
OF H IS 80TH B IRTHDAY)
On Apr. 3, 1979, P ro fessor Vladimir Vasil ' er ich Lapin, Doctor of Geological and Mineralogical Sciences, the famous Soviet scientist and one of the founders of industrial stone petrography, celebrated his 80th birthday.
P ro fessor Lapin began his scientific career at the end of the 1920s in the Department of Mineralogy at the Leningrad Polytechnic Institute which was then headed by the outstanding Soviet scientist D. S. Belyankin.
P ro fessor Lapin took part in the very important and useful scientific work of Academician Belyankin in his study of the phase relat ionships in industrial mater ia ls during manufacture, and in their service as f inished products. P ro fessor Lapin became the second in command to Academician Belyankin and later was in charge of the entire scientific school.
P ro fessor Lapin has worked in the Academy of Sciences of the USSR for approximately 50 years . His scientif ic career has been marked by its unusual diversity and conf i rms the bright and multifacetted talent of P ro fessor Lapin, a scientist of world renown. The fundamental monography of P ro fessor Lapin, "Pet ro - graphy of Metal lurgical and Fuel Slags" which was awarded a pr ize by the Pres id ium of the Academy of Sciences of the USSR has been widely acclaimed in the USSR and abroad. Altogether, he has published more than 200 scientific papers. He was involved in the multivolume work, "Phase Diagrams of Silicate Systems"
Translated from Ogneupory, No. 6, pp. 55-56, June, 1979.
0034-3102/79/0506-0385 $07~ 9 1980 Pleaum Publishing Corporation 385
[in Russian] and in the excellent monograph, ~Petrography of Industrial Stones ~ [inRussian], which was written in cooperation with Academician D. S. Belyankin and Doctor B. u Ivanov.
P ro fessor Lapin was the f i rst to study and descr ibe in detail the numerous synthetic minerals: spinels of a distinctive composition: olivines~ pyroxenes; si l icophosphates, cuspidines; etc.
The subjects of P ro fessor Lapin' s work included dinas, chamotte, and zirconia ref ractor ies ; various slags; cement cl inker and products of the solidification of cements; ceramic; glass; and other mater ia ls . His work in connection with re f ractor ies has been extremely interesting and of pract ica l importance.
The study of fused alumina and alumina ref ractor ies has made it possible for Prof. Lapin to issue some recommendations for improving the production process for making insulators for spark plugs in internal combustion engines. His work on zirconia re f ractor ies and the behavior of zirconia and baddeleyite in ref ractory mater ia ls has become very Lmportant. Much attention has been attracted to his studies of non- metal l ic inclusions in steel and inclusions in glass. P ro fessor Lapin has described a pract ical and convenient method of discovering the nature of various inclusions.
In recent years he has been the init iator of the use of, and the inventor of, methods of using various slags in the production of some effective constructional mater ia ls .
His unusual enthusiasm for work, his modesty and simplicity, all combined with his sense of responsibi l i ty as a cit izen and has patr iot ism, these are the character is t ics of our scientist Vladimir Vasil ' er ich Lapin, a scientific worker whose labor and knowledge has served our people from day to day and year to year.
P ro fessor Lapin combined his scientific career with community work. His humanity has won universal esteem for him. He was elected and served for 11 years as a deputy to the Soviet of Worker Deputies from the Moskvoretsk Region of Moscow. Since 1960 he has been a member of the Editorial Board of the journal Ogneupory. His strength and knowledge have been devoted to the review and editing of Soviet art ic les.
Our country has appreciated the achievements of P ro fessor Lapin. He was awarded two Orders of the Red Labor Banner, the Order of the Red Star, and a number of medals.
P ro fessor Lapin whose birthday we celebrate continues to work in the field of industrial petrography, a science to which he has devoted his life. We cordial ly congratulate P ro fessor Lapin on his 80th Birthday and wish him the best of health, happiness, and new achievements in science for the benefit of our beloved country.