The effect of holding time on the size distribution of β-Si3 N4 particles and nucleation undercooling in multicrystalline silicon

2016 ◽  
Vol 13 (10-12) ◽  
pp. 822-826 ◽  
Author(s):  
Espen Undheim ◽  
Kai Erik Ekstrøm ◽  
Lars Arnberg ◽  
Randi Holmestad ◽  
Marisa Di Sabatino
2019 ◽  
Vol 118 ◽  
pp. 01051
Author(s):  
Hewei Jiang ◽  
Yangtian Ye ◽  
Ping Lu

The torrefaction experiments of four biomass including agricultural biomass (corn straw (CS) and wheat straw (WS)) and forestry biomass (polar wood (PW) and cedar wood (CW)) were carried out in a fixed bed reactor at torrefaction temperature of 200-300°C and holding time of 10-60min, the effects of torrefaction temperature and holding time on biochar grindability based on the component analysis and the particle size distribution of ground biomass and biochars. The obtained results indicated that the mass fraction of ground biochar with particle size less than 150 μm increases with increasing torrefaction temperature, and the mass fraction of ground biochar with particle size less than 150 μm achieves 100%. The larger the λC, the better the grindability of biochar. The correlation between the grindability of the woody biochar and the λC is not as good as that of the straw biochar. The grindability of corn straw biochar and cedar wood biochar is improved with the increase of holding time at the same torrefaction temperature, however, the grindability of wheat straw biochar and polar wood biochar gets a little change, which can keep good grindability at higher torrefaction temperature large than 275°C.


2007 ◽  
Vol 336-338 ◽  
pp. 2361-2362
Author(s):  
Shu Ai Li ◽  
Da Nian Liu ◽  
Jiang Hong Gong

A series of MnO-doped ZnO with different grain sizes and grain morphologies were prepared by sintering the samples at different temperatures for different holding times. The grain size distribution for each sample was determined. It was found that, although the grain size increases and the grain morphology varies with the sintering temperature and/or the holding time, the normalized grain size distribution keeps invariable.


Author(s):  
Jonas Schon ◽  
Antti Haarahiltunen ◽  
David P. Fenning ◽  
Tonio Buonassisi ◽  
Hele Savin ◽  
...  

1986 ◽  
Vol 23 (04) ◽  
pp. 851-858 ◽  
Author(s):  
P. J. Brockwell

The Laplace transform of the extinction time is determined for a general birth and death process with arbitrary catastrophe rate and catastrophe size distribution. It is assumed only that the birth rates satisfyλ0= 0,λj> 0 for eachj> 0, and. Necessary and sufficient conditions for certain extinction of the population are derived. The results are applied to the linear birth and death process (λj=jλ, µj=jμ) with catastrophes of several different types.


1984 ◽  
Vol 75 ◽  
pp. 607-613 ◽  
Author(s):  
Kevin D. Pang ◽  
Charles C. Voge ◽  
Jack W. Rhoads

Abstract.All observed optical and infrared properties of Saturn's E-ring can be explained in terms of Mie scattering by a narrow size distribution of ice spheres of 2 - 2.5 micron diameter. The spherical shape of the ring particles and their narrow size distribution imply a molten (possibly volcanic) origin on Enceladus. The E-ring consists of many layers, possibly stratified by electrostatic levitation.


Author(s):  
B. B. Rath ◽  
J. E. O'Neal ◽  
R. J. Lederich

Addition of small amounts of erbium has a profound effect on recrystallization and grain growth in titanium. Erbium, because of its negligible solubility in titanium, precipitates in the titanium matrix as a finely dispersed second phase. The presence of this phase, depending on its average size, distribution, and volume fraction in titanium, strongly inhibits the migration of grain boundaries during recrystallization and grain growth, and thus produces ultimate grains of sub-micrometer dimensions. A systematic investigation has been conducted to study the isothermal grain growth in electrolytically pure titanium and titanium-erbium alloys (Er concentration ranging from 0-0.3 at.%) over the temperature range of 450 to 850°C by electron microscopy.


Author(s):  
Robert J. Carroll ◽  
Marvin P. Thompson ◽  
Harold M. Farrell

Milk is an unusually stable colloidal system; the stability of this system is due primarily to the formation of micelles by the major milk proteins, the caseins. Numerous models for the structure of casein micelles have been proposed; these models have been formulated on the basis of in vitro studies. Synthetic casein micelles (i.e., those formed by mixing the purified αsl- and k-caseins with Ca2+ in appropriate ratios) are dissimilar to those from freshly-drawn milks in (i) size distribution, (ii) ratio of Ca/P, and (iii) solvation (g. water/g. protein). Evidently, in vivo organization of the caseins into the micellar form occurs in-a manner which is not identical to the in vitro mode of formation.


Author(s):  
Chung-kook Lee ◽  
Yolande Berta ◽  
Robert F. Speyer

Barium hexaferrite (BaFe12O19) is a promising candidate for high density magnetic recording media due to its superior magnetic properties. For particulate recording media, nano-sized single crystalline powders with a narrow size distribution are a primary application requirement. The glass-crystallization method is preferred because of the controllability of crystallization kinetics, hence, particle size and size distribution. A disadvantage of this method is the need to melt raw materials at high temperatures with non-reactive crucibles, e.g. platinum. However, in this work, we have shown that crystal growth of barium hexaferrite occurred during low temperature heat treatment of raw batches.


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