The crystallization and growth of AlB2 single crystal flakes in aluminum

1998 ◽  
Vol 13 (12) ◽  
pp. 3485-3498 ◽  
Author(s):  
C. Deppisch ◽  
G. Liu ◽  
A. Hall ◽  
Y. Xu ◽  
A. Zangvil ◽  
...  

An in situ high temperature heat treatment was used to investigate the crystallization and growth behavior of AlB2 flakes in aluminum. Aluminum samples containing 1.8% boron were heated above the liquidus and then rapidly cooled through the Al(L) + AlB12 region to avoid the formation of AlB12 crystals. Subsequently, a homogeneous distribution of high aspect ratio AlB2 flakes crystallized upon holding below the peritectic transition temperature. Growth rate in the (a) and (c) dimensions increased during elevated hold temperatures below the peritectic transition temperature. Surprisingly, faster cooling rates from above the liquidus to room temperature resulted in thinner, wider flakes. Similar to graphite this phenomenon is believed to result from a need to accommodate a changing misfit strain energy between the solidifying aluminum and the growing AlB2 flakes.

2021 ◽  
Vol 9 (16) ◽  
pp. 98-108
Author(s):  
Yuliia Kozonova ◽  
◽  
Liubov Teleghenko ◽  
Vita Atanasova ◽  

Deficiency of most micronutrients, imbalance in nutrition, together with a dangerous environmental situation in Ukraine, has led to a decrease in the immunity of the population and the spread of alimentary-dependent diseases. Due to the damaged immunological picture of the population in recent years, the relevance of the creation of immunomodulating products is significantly increasing. About 70% of dishes served in restaurant are released with sauces, which allows not only to improve the aroma, appearance and taste of the finished dish, but also to increase the content of the essential substances of the dish. In the assortment of sauce products on the Ukrainian market, most of the sauces contain preservatives, artificial stabilizers and emulsifiers that negatively affect the human body and are not recommended for daily consumption. The subject of research is sauce products for preventive nutrition with increased nutritional value, without the presence of artificial food additives in the composition. The purpose of the study is to develop formulations of immunomodulating sauces using natural raw materials. Methods. The object of the study - developed immunomodulating sauces. In the finished product, the following parameters were determined: titratable acidity (DSTU 4957:2008), microbiological indicators (GOST 10444.15-94, GOST 54728-92, GOST 10444.2-94, GOST 30519-97). The results of the study. As a result of a literature search, the substances were determined, their bigger content in dies being important for improvement in the state of the immune system. These substances include, first of all, antioxidant vitamins (C, A and E), polyunsaturated fatty acids (especially omega-3), mineral elements and other minor substances. During developing the formulations of immunomodulating sauces, twelve requirements were formulated.. As a result of the raw materials selection, three formulations of immunomodulating sauces have been proposed. In their technology, there is a high-temperature heat treatment, which allows maximizing the preservation of useful thermolabile components. Scope of research results. Ready-made sauces are sold in restaurant establishments and consumed locally. Due to their simplicity of preparation, they can also be recommended for making at home. The developed immunomodulating sauces have a pleasant appearance and harmonious taste, which is confirming the data of sugar-acid indices.


Author(s):  
K.I. Nedashkovskiy ◽  
A.V. Gulshin ◽  
Yu.M. Averina ◽  
V.A. Naumkina ◽  
V.V. Menshikov ◽  
...  

The paper presents investigation results and a technology for manufacturing fastener workpieces out of the 07Kh16N6-Sh (07Х16Н6-Ш) steel using high-temperature heat treatment. The steel undergoing our testing was additionally doped with molybdenum, as reflected in the 07Kh16N6M-Sh (07Х16Н6М-Ш) designation, which facilitated grain refinement. We implemented accelerated climate testing of bolts in order to assess the corrosion cracking resistance of 07Kh16N6-Sh (07Х16Н6-Ш), 07Kh16N6M-Sh (07Х16Н6М-Ш) and 13Kh15N4AM3-Sh (13Х15Н4АМ3-Ш) steel fasteners in maritime climates.


Author(s):  
S. Yang ◽  
X. Chen ◽  
S. Motojima

The carbon microcoils and carbon nanocoils were prepared by the catalytic pyrolysis of acetylene under the Ni and/or Fe-containing catalysts, and the growth pattern, morphology and growth mechanism of the carbon coils were examined in detail. The inner coil diameter of carbon microcoils are of several µm and coil gap from zero to several µm. The inner coil diameter of carbon nanocoils are from zero to several ten nm and coil gap from zero to several nm. The carbon microcoils are generally of double helix coils such as DNA while carbon nanocoils were single helix coils such as α-helix proteins, with spring-like or twisted forms. A catalyst grain was usually observed on the tip of carbon coil. The carbon nanocoils are almost amorphous and can be graphitized by the high temperature heat-treatment.


Carbon ◽  
2009 ◽  
Vol 47 (1) ◽  
pp. 215-225 ◽  
Author(s):  
G.G. Kuvshinov ◽  
I.S. Chukanov ◽  
Y.L. Krutsky ◽  
V.V. Ochkov ◽  
V.I. Zaikovskii ◽  
...  

1984 ◽  
Vol 36 ◽  
Author(s):  
T. Kook ◽  
R. J. Jaccodine

ABSTRACTThe diffusion of various dopants( B, P, As, and Sb) in (111) silicon during high temperature( 1100°C ) heat treatment in nitrogen depends on the capping layers, i.e., SiO2, Si3 N4, and SiO2 + Si3 N4, layers. The junction motion of all dopants were retar ed in the bare silicon compared with that in the SiO2 + Si3 N4 capped silicon. The apparently retarded junction motion of As and sb diffused specimens in the bare silicon is due to the severe out-diffusion loss of dopant atoms and As and Sb diffusion are in fact enhanced during thermal nitridation of silicon in N2.


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