Mkhitar HobosyanUniversity of Texas Rio Grande Valley · Department of Physics and Astronomy
Mkhitar Hobosyan
PhD
About
48
Publications
23,397
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
299
Citations
Citations since 2017
Introduction
Additional affiliations
January 2018 - July 2018
January 2011 - present
September 2007 - December 2010
Publications
Publications (48)
Twisted laminar superconducting composite structures based on multi-wall carbon nanotube (MWCNT) yarns were crafted by integrating magnesium and boron homogeneous mixture into the carbon nanotube (CNT) aerogel sheets. After the ignition of the Mg–B–MWCNT system, under the controlled argon environment, the high exothermic reaction between magnesium...
There is a growing interest on novel energetic materials called Nanoenergetic Gas-Generators (NGGs) which are potential alternatives to traditional energetic materials including pyrotechnics, propellants, primers and solid rocket fuels. NGGs are formulations that utilize metal powders as a fuel and oxides or hydroxides as oxidizers that can rapidly...
Carbon combustion synthesis of oxides was applied for quick and energy efficient production of multiferroic composite of cobalt ferrite and barium titanate to form Janus-like particles matrix structure. The exothermic oxidation of carbon nanoparticles with an average size of 5 nm and a specific surface area of 110 m²/g generates a self-propagating...
Nanoenergetic Materials have a broad area of development that is rapidly growing and has emerging applications in many areas, including high-power linear actuators, solid fuels micropropulsion systems, and biocidal agent defeat formulations. These nanomaterials are produced at the heterogeneous form, and typically, their reactions are highly exothe...
Hydroxide‐aluminum based nano‐energetic materials are new class of thermites which demonstrated high theoretical energy capacity of up to 50 kJ cm−3. Most of the hydroxide‐aluminum based systems exhibit a large gas generation (greater than two liters per gram) and high adiabatic combustion temperature (up to 3000 K), which ensures performance that...
There is a growing interest in novel energetic materials called nano-energetic gas generators (NGGs) which are potential alternatives to traditional energetic materials including pyrotechnics, propellants, primers, and solid rocket fuels. NGGs are formulations that utilize metal powders as a fuel and oxides or hydroxides as oxidizers that can rapid...
Bismuth oxide structures resembling flowers, bowties and brushwood-like assemblies were successfully produced utilizing microfluidic synthesis approach. The molecular length of surfactant polyethylene glycol (PEG) was critical in shaping the particle morphology, while the laminar flow in micro-channels assured the complete structures without breaka...
Twisted laminar composite structures for high power and large-stroke actuators based on coiled Multi Wall Carbon Nanotube(MWNT)composite yarns were crafted by integrating high-density Nanoenergetic Gas Generators (NGGs) into carbon nanotube sheets. The linear actuation force, resulting from the pneumatic force caused by expanding gases confined wit...
The iodine pentoxide is one of the most advanced oxidizers for nanostructured energetic formulations among the thermites due to the highest energy release per volume 25.7 kJ cm−3. The size and shape of iodine pentoxide particles have a strong impact on the pressurization rates during the reaction. Although micro-sized iodine pentoxide particles are...
In this article, we present experimental results of the combustion processes and thermal analysis of ammonium nitrate with carbonaceous materials. The thermal analysis was conducted by differential scanning calorimetry to investigate the decomposition of ammonium nitrate with carbonized rice husks and dextran. Differential scanning calorimetry data...
Carbon Combustion Synthesis of Oxides (CCSO) is a promising method to produce submicron- and nano- sized complex oxides. The CCSO was successfully utilized for producing several complex oxides, a complete theoretical model including the
sample porosity, flow parameters and reaction energetics is needed to predict the combustion parameters for CCSO....
Summary In this paper we applied the macro fluxes for simulation the hot gas flow in a channel with nanopores. The fluxes arise due to the flow peculiarities or the effects accompanying the flow such as: gas velocity slip, temperature and species concentration jumps at the pore surfaces as well as thermal radiation. The fluxes are obtained by the a...
We report the first study of gas generation and thermal wave behavior during the performance of a novel nano-energetic system based on aluminum and bismuth hydroxide Al-Bi(OH)3. Thermodynamic calculations demonstrate that this system is comparable to one of the most powerful known nano-thermite systems, Al-Bi2O3, in terms of energy capacity per ini...
There are technical barriers for penetration market requesting rechargeable lithium-ion battery packs for
portable devices that operate in extreme hot and cold environments. Many portable electronics are used in
very cold (-40 °C) environments, and many medical devices need batteries that operate at high temperatures.
Conventional Li-ion batteries...
DOI: 10.1615/NanomechanicsSciTechnolIntJ.v6.i3.40
Macroflows are considered for simulation of hot gas flow in a channel with nanopores. The flows
are caused by the effects of gas slip, jumps of temperature and concentrations of gas mixture
components on the surface of pores. The macroflows are obtained by averaging microflows in
nanopores. The int...
Rare earth ferrites exhibit remarkable magnetodielectric properties that are sensitive to the crystallite size. There is a major challenge to produce these materials in nanoscale due to particles conglomeration during the ferrite nucleation and synthesis. In this paper we report the fabrication of nanostructured particles of rare earth ferrites in...
Differential scanning calorimetry and a high-speed temperature scanner were used to characterize dynamic features of the reaction between polytetrafluoro-ethylene (PTFE) and Al 2 O 3 under heating rates ranging between 20 and 780 °C min -1 . Exothermic reaction behavior between PTFE and Al 2 O 3 was observed at heating rates of 150 °C min -1 and hi...
Differential scanning calorimetry and a high-speed temperature scanner were used to characterize dynamic features of the reaction between polytetrafluoro-ethylene (PTFE) and Al 2 O 3 under heating rates ranging between 20 and 780 °C min-1. Exothermic reaction behavior between PTFE and Al 2 O 3 was observed at heating rates of 150 °C min-1 and highe...
It is widely recognized that future exploration missions to the Moon will include construction of permanent lunar bases to support long-term lunar missions. The lunar in situ resource utilization concept to produce superior construction materials is a vital part of exploration missions. This paper presents a novel approach for consolidation of luna...
Solid propellants are used in various flight and underwater systems as well as in propulsion platforms. Micromachining, microelectromechanical systems (MEMS) and automatic dispensing of high-energy-density nano-energetic materials are examined for current and next generation of application-specific flight and underwater platforms. The integrated ME...
The specific energy of the existing lithium ion battery cells is limited because intercalation electrodes made of activated carbon (AC) materials have limited lithium ion storage capacities. Carbon nanotubes, graphene, and carbon nanofibers are the most sought alternatives to replace AC materials but their synthesis cost makes them highly prohibiti...
Lithium cobaltate (LiCoO2) was produced by carbon combustion synthesis of oxide (CCSO) using carbon nanoparticles as a fuel. In this method, the exothermic oxidation of carbon nanoparticles with an average size of 5 nm (specific surface 80 m2/g) gives rise to a self-propagating thermal wave with maximum temperatures of up to 900°C. The thermal fron...
We study microthrusters which can be used in various flight and underwater platforms. The MEMS-technology thrusters with Al/I2O5 and Al/Bi2O3 nanostructured energetic composites increase thrust-to-weight ratio and energy density, thereby ensuring enabling capabilities. The integrated micromachining ensures overall technology compatibility, scalabil...
The ternary oxide system Y-Fe-O presents fascinating magnetic properties that are sensitive to the crystalline size of particles. There is a major challenge to fabricate these materials in nano-crystalline forms due to particle conglomeration during nucleation and synthesis. In this paper we report the fabrication of nano sized crystalline yttrium...
The dynamic features of Al2O3 - polytetrafluoroethylene (PTFE) and Al - PTFE reactions in non-isothermal conditions are presented. The Differential Scanning Calorimetry (DSC) and High-Speed Temperature Scanner (HSTS) were used to characterize the Al2O3/Al – PTFE reactions at different heating rates. The study shows that the HSTS instrument can give...
The crystalline LiCoO2 nanoparticles were synthesized by carbon combustion synthesis of oxide (CCSO). The thermo-gravimetric analysis was used to identify interaction features in the system LiNO3 - Co 3O4 - Carbon to produce LiCoO2. The major parameters affecting the process are the carbon concentration in the reactant mixture and the ability of th...
Nanoenergetic Gas-Generators are formulations that rapidly release a
large amount of gaseous products and generate a fast moving thermal
wave. They are mainly based on thermite systems, which are pyrotechnic
mixtures of metal powders (fuel- Al, Mg, etc.) and metal oxides
(oxidizer, Bi2O3, Fe2O3,
WO3, MoO3 etc.) that can generate an exothermic
oxida...
This paper reports our findings in novel enabling high-energy-density nanostructured materials for micro-propulsion and other applications. In order to ensure the overall functionality, the system-level solution is achieved by integrating of synthesized nanoenergetic materials using microelectromechanical systems (MEMS). The MEMS solution provides...
In this work we first time investigate the reaction mechanism and possibility of synthesizing NiAl intermetallic compound under the activated combustion mode. A halogen containing organic polymer, namely, polytetrafluoroethylene – PTFE is used as promoter. It is shown that the single-phase target product is obtained when amount of the promoter is 0...
The concept of sintering of lunar regolith with activated thermites is
provided. The thermodynamic calculations and experimental procedures are
provided to demonstrate the effectiveness of new route of regolith
sintering under the lunar environment.
The risk of bioterrorism events involving the intentional airborne release of contagious agents has led to development of new approaches for bio agent defeat technologies both indoors and outdoors. The spore-forming bacteria, in particular Bacillus anthracis is one of the biologic agents most likely to be used as a bio-weapon. Novel approaches to d...
The risk for bioterrorist events involving the intentional airborne
release of contagious agents has led to development of new approaches
for bio agent defeat technologies both indoors and outdoors. Novel
approaches to defeat harmful biological agents have generated a strong
demand for new active materials. The preferred solutions are to
neutralize...
NASA's anticipated returns to the Moon by 2020, subsequent establishment
of lunar in situ resource utilization technologies are essential. The
surface of Moon is covered with small eroded particles of regolith
called lunar dust that adheres electro-statically to everything coming
in contact with it, and is of much concern for future lunar base beca...
A feasibility of combustion synthesis of lithium cobaltate powders using oxide sources was investigated. Cobalt oxide Co3O4 and lithium carbonate Li2CO3 were used as starting reactants. Two different oxidizers were explored: (i) ammonia nitrate NH4NO3 and (ii) lithium nitrate LiNO3. Some organic reducers (ORs)—such as CH-polymers, melamine, urotrop...
In this work the feasibility of synthesizing MoSi2/Al cermet foam under the combustion mode was studied. A halogen containing organic polymer, namely, polytetrafluoroethylene (PTFE) was used as foaming agent. It was shown that the target product reached the maximum porosity, up to 70%, when amount of the foaming agent was 0.04mol. SEM analyses have...
In the present study we report the preparation of TiC - ZrC powder blend in one-step process of synthesis. Powders have been produced by means of Self Propagating High Temperature syntheses (SHS) single mode using two approaches: (i) addition of ZrC powder into Ti+C green mixture, and (ii) addition TiC powder into Zr+C mixture. Special attention wa...
Aluminum diboride was chosen as an initial reagent to obtain BN/AlN composites with high homogeneity. By comparing the specific surface area of products, it was established that this parameter can be increased (up to 10-24 m 2 /g) by increasing the amount of boron nitride. The gasifying compounds have essential influence on the formation of submicr...
IntroductionThermodynamic ConsiderationsExperimentalResults and DiscussionConclusions
Acknowledgement
Questions
Questions (3)
I am looking for good papers about re-agglomeration of particles during long mechanical milling times. I know that there is an optimal milling time before which particle size reduces, and after some critical time the particles re-agglomerate and average particle size increases.
Does anyone know a good review or experimental paper (preferably with mathematical models) that describes this phenomena? P.S. The reason for re-agglomeration may be due to excessive surface energy that accumulates on small particles and after some (long) time the particles re-agglomerate to reduce the overall surface energy, as I understand.
I know you can reduce Fe2O3 to Fe3O4 with controlled reducing at 1000 C with methane.
Now, without reducers, I heat MgFexOy (which is not magnetic and nano-sized particles) at 1000 C for 6 hours in air, and they become magnetic (emu/g is increased by an order of magnitude). Is it possible that I have MgO-Fe3O4 but nanoparticles are not well crystallized and do not show high magnetism, and when I heat, they crystallize and show better magnetic properties? I think it is impossible that this was iron with +3 oxidation state and without reducers I could receive Fe(II, III) ion mixture.
Anyone has seen or can explain this? Thanks in advance.
The problem is that even during non-contact imaging nanoparticles are moving on mica surface causing "smearing" of the image. I tried isopropanol suspended particle deposition, drying and washing with isopropanol, but still particles are not well attached. There might be a method to suspend particles in some polymer solution and receive spin-coated surface on mica. Any suggestions?
Projects
Projects (3)
To develop activation methods for combustion of systems with low energetic reserves. In addition, pre-treatment or in situ activation allows to manipulate the combustion laws and govern obtained particle size and morphology.
