Begell House Inc.
Nanoscience and Technology: An International Journal
NST
2572-4258
5
4
2014
STRUCTURAL MECHANICAL PROPERTIES OF HUMIC SUBSTANCES USED AS COMPONENTS OF MAGNETIC NANOCOMPOSITES
255-266
10.1615/NanomechanicsSciTechnolIntJ.v5.i4.10
S. P.
Li
Kyrgyz Zh. Balasagyn National University, 547 Frunze Str., Bishkek, 720033, Kyrgyzstan
V. A.
Prokhorenko
Institute of Chemistry and Chemical Technology, 267 Chuyski Ave., Bishkek, 720071, Kyrgyzstan
S. J.
Jorobekova
Institute of Chemistry and Chemical Technology, 267 Chuyski Ave., Bishkek, 720071, Kyrgyzstan
humic acids
polyvalent metal humates
structure formation
plasto-viscoelastic properties
This study is devoted to investigation of plasto-viscoelastic properties of soluble humate hydrogels with the aqueous medium pH 6−7, obtained by neutralizing relevant alkaline extracts by various acid solutions, and insoluble humates of polyvalent metals. The comparative study of the structure formation processes in gels of soluble sodium and potassium humates with pH 6−7, containing a mineral salt, shows that the dispersed medium composition affects plasto-viscoelastic properties of the coagulation medium. When potassium humates contain KNO3 salts, the CCS value compared to a gel without KNO3 reduces from 17% to 13.6% of the dispersed phase, thereby enhancing the structure. In potassium humates, the NaNO3 salt has an opposite action, i.e., it deteriorates the structure formation properties; compared to a gel without NaNO3 the CCS increases from 10% to 14% of the dispersed phase, reducing the strength of the coagulation structure. The produced samples of insoluble iron (III) humates are the products of incomplete substitution of the Na+ ion from the acid groups of the soluble form of humic acids. The structure formation capacity of the hydrogel with the H+ form of humic acids is expressed much weaker compared to hydogels of iron humates. This is demonstrated by the high CCS value (22% of the dispersed phase) and the low values of the strength parameters at CCS.
HEAT-RESISTANT NON-FIRED REPAIR COATINGS FOR PROTECTION OF CARBON-BASE MATERIALS
267-285
10.1615/NanomechanicsSciTechnolIntJ.v5.i4.20
A. N.
Astapov
Moscow Aviation Institute (National Research University), 4 Volokolamskoe
Highway, Moscow, 125080, Russia
carbon-base material
CCCMs
CCMCs
structural graphite
gas corrosion
heat resistance
nanodispersed silica sol
non-fired repair coating
high-enthalpy flow
gas-dynamic testing
The method for generating heat-resistant protective coatings of silicide type by non-fired technology is presented. The binder of the slip suspension was a nanodispersed silica sol, and the fillers were powders of the previously developed materials of the Si−TiSi2−MoSi2−B−Y and Si−TiSi2−MoSi2−B−Y−SiC systems. Such coatings are designed to protect heat-resistant carbon-base materials (carbon−carbon composite materials (CCCM) and carbon−ceramic matrix composites (CCMC), structural graphite) against high-temperature gas corrosion. This method allows one to minimize the problems encountered when it is necessary to protect the connecting units of the prefabricated structural elements, inter alia, elements of high dimensions (wing edges, protective screens, casings, etc.), as well as to solve problems related to repair of various damages of standard coatings that are inevitable during the assembly and/or operation of the space-rocket hardware.
SORPTION PROPERTIES OF PECTIC NANOCOMPOSITES IN RELATION TO LEAD IONS
287-301
10.1615/NanomechanicsSciTechnolIntJ.v5.i4.30
N. G.
Zakharova
Moscow Aviation Institute (National Research University),
4 Volokolamskoe Shosse, A80, Moscow, 125993, Russia
N. D.
Golubeva
Institute of Problems of Chemical Physics, Russian Academy of Sciences,
1 Academician Semenov Ave., Chernogolovka, Moscow Region, 142432,
Russian Federation
N. V.
Gorbunova
OJSC Institute of Applied Biochemistry and Machine Building (Biokhimmash)
Gulzhian I.
Dzhardimalieva
Moscow Aviation Institute (National Research University), 4 Volokolamskoe
Highway, Moscow, 125993, Russian Federation; Institute of Problems of Chemical Physics of the Russian Academy of Sciences,
1 Akad. Semenov Ave., Chernogolovka, Moscow Region, 142432, Russian Federation
A. D.
Pomogailo
Moscow Aviation Institute (National Research University),
4 Volokolamskoe Shosse, A80, Moscow, 125993, Russia; Institute of Physical Chemistry Problems, Russian Academy of Sciences
Kamila A.
Kydralieva
Moscow Aviation Institute (National Research University), 4 Volokolamskoe Highway, Moscow, 125993, Russia
magnetite nanoparticles
pectin
encapsulated composite
lead
sorption
The method of chemical co-deposition of iron (II, III) chloride solutions in the pectin medium was used to produce Fe3O4 nanoparticles with a size of about 10 nm. The introduction of Ca2+ ions leads to a decrease in the size of Fe3O4−PecCa nanoparticles in comparison with the Fe3O4−Pec samples due to additional cross-linking of pectic carboxyl groups by Ca2+ ions. The increase of the sorption capacity of the Fe3O4−PecCa and Fe3O4−Pec nanocomposites in relation to Pb2+ in comparison with the native pectin was demonstrated. The log K values of Pb2+ sorption for the Pec, Fe3O4−Pec10, and Fe3O4−PecCa0.15 sorbents were 4.2, 4.9, and 4.6 1/M, respectively.
BASIC PRINCIPLES OF ALUMINUM DEPOSITION ON A HARD ALLOY IN PRODUCING OXIDE COATING
303-312
10.1615/NanomechanicsSciTechnolIntJ.v5.i4.40
V. N.
Anikin
National University of Science and Technology "MISiS", 4 Leninskiy Ave., Moscow, 119049, Russian Federation
A. I.
Pyanov
National University of Science and Technology "MISiS", Moscow, Russia
composite coatings
aluminum oxide
resistance
aluminum
hard alloy
study of the composition
micro/nanostructure
High temperatures have an adverse effect on the physical and chemical characteristics of tools. This problem can be solved by using Al2O3-based composite coatings, produced by the micro-arc oxidation method; these coatings have the tool resistance factor two times higher than that of the hard alloy plates with a traditional coating. The opportunity for the industrial implementation of the technology of applying Al2O3-based coatings on the cutting tools is discussed. The composition of coatings and their deposition on the substrate under various technological conditions are analyzed at the micro- and nanoscale levels. The relationships between the micro-nanostructure parameters and the coating operation efficiency are evaluated.
RECRYSTALLIZATION PROCESSES IN AUSTENITIC ALLOY PRODUCED BY SELECTIVE LASER MELTING
313-322
10.1615/NanomechanicsSciTechnolIntJ.v5.i4.50
K. O.
Bazaleeva
N. E. Bauman Moscow State Technical University, Moscow, Russia
E. V.
Tsvetkova
JSC All-Russia Research Institute of Inorganic Materials, Moscow, Russia
E. V.
Balakirev
Federal State Unitary Enterprise "All-Russia Research Institute of Aviation
Materials", State Scientific Center, 17 Radio Str., Moscow, 105005, Russia
selective laser melting
thermal stability
austenitic alloy
The thermal stability of the austenitic Fe−17%Cr−12%Ni−2%Mo−1%Mn−0.7%Si−0.02%C alloy, produced by selective laser melting, was investigated. It is shown that the cellular structure is retained in the alloy up to 800°C. With further increase in the annealing temperature, the dislocation structure of the alloy changes (800−950°) and the solid solution supersaturated with atmosphere atoms decomposes (1050−1150°).
THE STRUCTURE OF NANOCOMPOSITES BASED ON MAGNETITE AND HUMIC ACIDS PRODUCED BY CHEMICAL COPRECIPITATION AND MECHANOCHEMICAL SYNTHESIS
323-336
10.1615/NanomechanicsSciTechnolIntJ.v5.i4.60
A. A.
Yurishcheva
Moscow Aviation Institute (National Research University),
4 Volokolamskoe Shosse, Moscow A80, 125993, Russian Federation
Gulzhian I.
Dzhardimalieva
Moscow Aviation Institute (National Research University), 4 Volokolamskoe
Highway, Moscow, 125993, Russian Federation; Institute of Problems of Chemical Physics of the Russian Academy of Sciences,
1 Akad. Semenov Ave., Chernogolovka, Moscow Region, 142432, Russian Federation
E. J.
Kasymova
Institute of Chemistry and Chemical Technology, National Academy of Sciences, Kyrgyzstan
S. I.
Pomogailo
Institute of Problems of Chemical Physics, Russian Academy of Sciences, 1 Akademik Semenov Ave., Chernogolovka, Moscow Region, 142432, Russia
Kamila A.
Kydralieva
Moscow Aviation Institute (National Research University), 4 Volokolamskoe Highway, Moscow, 125993, Russia
S. P.
Li
Kyrgyz Zh. Balasagyn National University, 547 Frunze Str., Bishkek, 720033, Kyrgyzstan
magnetite nanoparticles
humic acids
chemical coprecipitation
mechanochemical dispersion
structure
A comparative analysis of methods used for obtaining hybrid functional materials based on magnetite nanoparticles and humic acids by in situ chemical co-deposition or mechanochemical dispersion showed that the method of in situ chemical co-deposition is optimal for producing Fe3O4−HA nanocomposites with reproducible sizes and structure. The possibility of regulating the sizes and magnetic properties of magnetite nanoparticles by varying the Fe3O4 and HAs ratio in the composite is demonstrated. The mechanochemical synthesis method provided opposite results in terms of decrease and increase of particle sizes, which varied in a broad range from nanoscale to micrometer sizes depending on synthesis conditions, accompanied by their increased size distribution. X-ray phase and Mossbauer studies of the hybrid material samples produced by mechanochemical synthesis showed parameters not typical of the magnetite phase.
AUTHOR INDEX
337-338
10.1615/NanomechanicsSciTechnolIntJ.v5.i4.70
SUBJECT INDEX
339-340
10.1615/NanomechanicsSciTechnolIntJ.v5.i4.80
TABLE OF CONTENTS
341-344
10.1615/NanomechanicsSciTechnolIntJ.v5.i4.90