In order to ensure the health and welfare of livestock, there has been an emphasis on precision f... more In order to ensure the health and welfare of livestock, there has been an emphasis on precision farming of ruminant animals. Monitoring the life index of ruminant animals is of importance for intelligent farming. Here, a wearable sensor for monitoring ultraviolet (UV) radiation is demonstrated to understand the effect of primary and secondary photosensitization on dairy animals. Thin films of wide bandgap semiconductor zinc oxide (ZnO) comprising multilevel of nanostructures from microparticles (MP) to nanoparticles (NP), and tetrapod (T–ZnO), were prepared as the UV sensing active materials. The sensitivity was evaluated by exposing the films to various radiation sources, i.e., 365 nm (UV A), 302 nm (UV B), and 254 nm (UV C), and measuring the electrical resistance change. T–ZnO is found to exhibit higher sensitivity and stable response (on/off) upon exposure to UV A and UV B radiation, which is attributed to their higher surface area, aspect ratio, porosity, and interconnective ne...
Nanocrystal-assembled cubic boron nitride (cBN) islands are formed by using low-energy (∼20eV) io... more Nanocrystal-assembled cubic boron nitride (cBN) islands are formed by using low-energy (∼20eV) ion irradiation in an inductively coupled fluorine-containing plasma. The temporal evolution of surface morphology and roughness reveals three-dimensional island growth for initial sp2-bonded BN and subsequent cBN, accompanied by a high frequency of renucleation. The formation of cBN islands enhances the field emission and reduces the turn-on field down to around 9V∕μm due to an increase in the island-related field. The results demonstrate the high potential of cBN for field emitters, comparable to other wide band gap semiconductors.
Electroactivity of graphene-family nanomaterials and three-dimensional porous architectures is ke... more Electroactivity of graphene-family nanomaterials and three-dimensional porous architectures is key for various applications at the grand challenges of “energy-water-sensing nexus.” It requires well-controlled morphology, manipulation of surface chemistry, interconnected topologic network, as well as electronic properties. Here, we demonstrate by taking advantage of hierarchical mesoporosity, optimized defects number density, nD (edges-plane and pore sites, oxygenated and nitrogenated functionalities), further invoked by synergistic coupling between one-dimensional single-walled carbon nanotube (SWCNT) as “nano” spacers and polymer linker with two-dimensional reduced graphene oxide derived three-dimensional scaffolds (known as aerogels) under hydrothermal conditions, and improved electrochemical (re)activity by enhancing the heterogeneous electron transfer rate (kET). We determined the correlation among nD, in-plane sp2C cluster, La and interdefect distance, LD (all via Raman spectro...
We report the development of hybrids consisting of supercapacitive graphene oxide (GO), reduced G... more We report the development of hybrids consisting of supercapacitive graphene oxide (GO), reduced GO (rGO), electrochemically reduced GO (ErGO), multilayer graphene (MLG) decorated with pseudocapacitive nanostructured cobalt oxides (CoO, Co 3 O 4 ) and nanoparticles (CoNP) via electrodeposition and hydrothermal synthesis facilitating chemically bridged (covalently and electrostatically anchored) interfaces with tunable properties. These hybrid samples showed heterogeneous transport behavior determining diffusion coefficient (4 × 10 −8 –6 × 10 −6 m 2 /s) following CoO/MLG 3 O 4 /MLG 3 O 4 /rGO HT 550 F/g for Co 3 O 4 /ErGO and Co 3 O 4 /MLG. We found an ultrahigh sensitivity of 4.57 mA/(mM cm 2 ) and excellent limit of glucose detection 3 O 4 /rGO HT 3 O 4 /MLG. These findings are due to open pore network and topologically multiplexed conductive pathways provided by graphene nanoscaffolds to ensure rapid charge transfer and ion conduction. Density functional theory determined density of states in the vicinity of Fermi level in-turn providing contribution toward electroactivity due to orbital re-hybridization.
In this paper, we explain the concept, characteristics and need of big data and different offerin... more In this paper, we explain the concept, characteristics and need of big data and different offerings available in the market to explore unstructured large data. This paper covers big data adoption trends, entry and exit criteria for the vendor and product selection, best practices, customer success story, benefits of big data analytics, summary and conclusion. Our analysis illustrates that the big data analytics is a fast-growing, influential practice and a key enabler for the social business. The insights gained from the user generated online contents and collaboration with customers is critical for success in the age of social media.
ABSTRACTCarbon nanotubes (CNTs) are of great interest because of several unsurpassable physical (... more ABSTRACTCarbon nanotubes (CNTs) are of great interest because of several unsurpassable physical (mechanical, electrical, thermal, and chemical) properties. Especially their large elastic modulus and breaking strength make them highly attractive for their use as reinforced agents in forming a new class of multifunctional advanced materials - onanocomposites, in addition to high conductivity (either in semiconducting or metallic regimes) achieved through lower percolation thresholds for several electronic applications. Among the known conducting polymers, polyaniline (PANI) has a high potential due to its ease of synthesis, excellent environmental, and thermal stability and reversible control of its electrical/electronic properties. In this work, PANI-single-/multiwalled NTs composites films containing different nanotube content of both kinds were synthesized by spin-cast preceded by ultrasonic mixing of the constituents. They were characterized using complementary techniques includin...
ABSTRACTRelaxors (PZN, in particular) is an important class of self-assembled nanostructure compo... more ABSTRACTRelaxors (PZN, in particular) is an important class of self-assembled nanostructure composite ferroelectric oxides (or perovskite) materials. The interesting features associated with the nanoregions/nanodomains required to describe these relaxors give rise to the most relevant device related characteristics and peculiar physical properties in these materials. In addition, they possess astronomical property coefficients by themselves or when modified with lead titanate (PT) forming solid solution. In the past, we conducted temperature dependent Raman scattering studies on solid solution (1−x)PZN−xPT relaxors single crystals with varying composition; x = 0.02, 0.085, and 0.11. These studies were performed to obtain relevant information about lattice/phonon dynamics for matching the application criteria such as electromechanical actuators. We showed that the sharp structural phase transition occurs at or near 460 K which is a first-order transition by fitting two spectroscopic ...
ABSTRACTMaterials science is playing a dramatic role in discovering new materials with tailored p... more ABSTRACTMaterials science is playing a dramatic role in discovering new materials with tailored physical properties. Cold cathodes/field emitters are one of the examples. Electron field emitting materials are of vital importance for a variety of vacuum microelectronic devices including field emission displays for flat panel displays, electron microscopes, X-ray generators, and vacuum lamps. This is the driving force to investigate the advanced nanostructured carbons as cold cathodes as one of the potential candidates. Recently, they are also being proposed for thermionic power generators. The rationale is that reducing one or more dimensions of a system below some critical length changes the systems' physical properties, where carbon nanotubes (CNTs) in the class of carbon nanostructures serve as a model example. In this paper, synthesis and characterization of vertically aligned multiwall and single-/double-wall carbon nanotube films using a microwave plasma-assisted chemical v...
2007 International Semiconductor Device Research Symposium, 2007
... Engineered Surfaces of Multifunctional and Molecular Diamond for Biosensing Sanju Gupta ... W... more ... Engineered Surfaces of Multifunctional and Molecular Diamond for Biosensing Sanju Gupta ... With the recent development in nanoscience and nanotechnology, carbon-based nanomaterials (eg fullerenes, nanotubes, nanodiamond) are receiving much attention due to their ...
ABSTRACTSevere environmental tolerability is the prime factor in the development of novel space m... more ABSTRACTSevere environmental tolerability is the prime factor in the development of novel space materials exhibiting excellent physical properties accompanied by lightweight, reusability, and multifunctional capabilities. Diamond is known for its reputation being radiation hard besides a range of outstanding properties (electronic, optical, mechanical, and chemical) and hence it is preferable in harsh environments. Carbon nanotubes are also of great interest because of several unsurpassable physical properties and it needs to be shown that they are physically stable and structurally unaltered when subjected to irradiation. Therefore, a family of novel nanocarbons (nanodiamond and nanotubes) films deposited by microwave plasma-assisted chemical vapor deposition (MWCVD) technique was subjected to gamma radiation (1, 5, and 20 Mrads) and to medium energy electron-beam irradiation to study their effects on the microscopic structure and corresponding physical properties to establish prop...
ABSTRACT-Image Enhancement is one of the basic requirements for making an image useful for variou... more ABSTRACT-Image Enhancement is one of the basic requirements for making an image useful for various statistical analysis and particle identification that form the basis of various tests and measurements in Digital Photography, Biomedical Tests and Measurements, ...
In order to ensure the health and welfare of livestock, there has been an emphasis on precision f... more In order to ensure the health and welfare of livestock, there has been an emphasis on precision farming of ruminant animals. Monitoring the life index of ruminant animals is of importance for intelligent farming. Here, a wearable sensor for monitoring ultraviolet (UV) radiation is demonstrated to understand the effect of primary and secondary photosensitization on dairy animals. Thin films of wide bandgap semiconductor zinc oxide (ZnO) comprising multilevel of nanostructures from microparticles (MP) to nanoparticles (NP), and tetrapod (T–ZnO), were prepared as the UV sensing active materials. The sensitivity was evaluated by exposing the films to various radiation sources, i.e., 365 nm (UV A), 302 nm (UV B), and 254 nm (UV C), and measuring the electrical resistance change. T–ZnO is found to exhibit higher sensitivity and stable response (on/off) upon exposure to UV A and UV B radiation, which is attributed to their higher surface area, aspect ratio, porosity, and interconnective ne...
Nanocrystal-assembled cubic boron nitride (cBN) islands are formed by using low-energy (∼20eV) io... more Nanocrystal-assembled cubic boron nitride (cBN) islands are formed by using low-energy (∼20eV) ion irradiation in an inductively coupled fluorine-containing plasma. The temporal evolution of surface morphology and roughness reveals three-dimensional island growth for initial sp2-bonded BN and subsequent cBN, accompanied by a high frequency of renucleation. The formation of cBN islands enhances the field emission and reduces the turn-on field down to around 9V∕μm due to an increase in the island-related field. The results demonstrate the high potential of cBN for field emitters, comparable to other wide band gap semiconductors.
Electroactivity of graphene-family nanomaterials and three-dimensional porous architectures is ke... more Electroactivity of graphene-family nanomaterials and three-dimensional porous architectures is key for various applications at the grand challenges of “energy-water-sensing nexus.” It requires well-controlled morphology, manipulation of surface chemistry, interconnected topologic network, as well as electronic properties. Here, we demonstrate by taking advantage of hierarchical mesoporosity, optimized defects number density, nD (edges-plane and pore sites, oxygenated and nitrogenated functionalities), further invoked by synergistic coupling between one-dimensional single-walled carbon nanotube (SWCNT) as “nano” spacers and polymer linker with two-dimensional reduced graphene oxide derived three-dimensional scaffolds (known as aerogels) under hydrothermal conditions, and improved electrochemical (re)activity by enhancing the heterogeneous electron transfer rate (kET). We determined the correlation among nD, in-plane sp2C cluster, La and interdefect distance, LD (all via Raman spectro...
We report the development of hybrids consisting of supercapacitive graphene oxide (GO), reduced G... more We report the development of hybrids consisting of supercapacitive graphene oxide (GO), reduced GO (rGO), electrochemically reduced GO (ErGO), multilayer graphene (MLG) decorated with pseudocapacitive nanostructured cobalt oxides (CoO, Co 3 O 4 ) and nanoparticles (CoNP) via electrodeposition and hydrothermal synthesis facilitating chemically bridged (covalently and electrostatically anchored) interfaces with tunable properties. These hybrid samples showed heterogeneous transport behavior determining diffusion coefficient (4 × 10 −8 –6 × 10 −6 m 2 /s) following CoO/MLG 3 O 4 /MLG 3 O 4 /rGO HT 550 F/g for Co 3 O 4 /ErGO and Co 3 O 4 /MLG. We found an ultrahigh sensitivity of 4.57 mA/(mM cm 2 ) and excellent limit of glucose detection 3 O 4 /rGO HT 3 O 4 /MLG. These findings are due to open pore network and topologically multiplexed conductive pathways provided by graphene nanoscaffolds to ensure rapid charge transfer and ion conduction. Density functional theory determined density of states in the vicinity of Fermi level in-turn providing contribution toward electroactivity due to orbital re-hybridization.
In this paper, we explain the concept, characteristics and need of big data and different offerin... more In this paper, we explain the concept, characteristics and need of big data and different offerings available in the market to explore unstructured large data. This paper covers big data adoption trends, entry and exit criteria for the vendor and product selection, best practices, customer success story, benefits of big data analytics, summary and conclusion. Our analysis illustrates that the big data analytics is a fast-growing, influential practice and a key enabler for the social business. The insights gained from the user generated online contents and collaboration with customers is critical for success in the age of social media.
ABSTRACTCarbon nanotubes (CNTs) are of great interest because of several unsurpassable physical (... more ABSTRACTCarbon nanotubes (CNTs) are of great interest because of several unsurpassable physical (mechanical, electrical, thermal, and chemical) properties. Especially their large elastic modulus and breaking strength make them highly attractive for their use as reinforced agents in forming a new class of multifunctional advanced materials - onanocomposites, in addition to high conductivity (either in semiconducting or metallic regimes) achieved through lower percolation thresholds for several electronic applications. Among the known conducting polymers, polyaniline (PANI) has a high potential due to its ease of synthesis, excellent environmental, and thermal stability and reversible control of its electrical/electronic properties. In this work, PANI-single-/multiwalled NTs composites films containing different nanotube content of both kinds were synthesized by spin-cast preceded by ultrasonic mixing of the constituents. They were characterized using complementary techniques includin...
ABSTRACTRelaxors (PZN, in particular) is an important class of self-assembled nanostructure compo... more ABSTRACTRelaxors (PZN, in particular) is an important class of self-assembled nanostructure composite ferroelectric oxides (or perovskite) materials. The interesting features associated with the nanoregions/nanodomains required to describe these relaxors give rise to the most relevant device related characteristics and peculiar physical properties in these materials. In addition, they possess astronomical property coefficients by themselves or when modified with lead titanate (PT) forming solid solution. In the past, we conducted temperature dependent Raman scattering studies on solid solution (1−x)PZN−xPT relaxors single crystals with varying composition; x = 0.02, 0.085, and 0.11. These studies were performed to obtain relevant information about lattice/phonon dynamics for matching the application criteria such as electromechanical actuators. We showed that the sharp structural phase transition occurs at or near 460 K which is a first-order transition by fitting two spectroscopic ...
ABSTRACTMaterials science is playing a dramatic role in discovering new materials with tailored p... more ABSTRACTMaterials science is playing a dramatic role in discovering new materials with tailored physical properties. Cold cathodes/field emitters are one of the examples. Electron field emitting materials are of vital importance for a variety of vacuum microelectronic devices including field emission displays for flat panel displays, electron microscopes, X-ray generators, and vacuum lamps. This is the driving force to investigate the advanced nanostructured carbons as cold cathodes as one of the potential candidates. Recently, they are also being proposed for thermionic power generators. The rationale is that reducing one or more dimensions of a system below some critical length changes the systems' physical properties, where carbon nanotubes (CNTs) in the class of carbon nanostructures serve as a model example. In this paper, synthesis and characterization of vertically aligned multiwall and single-/double-wall carbon nanotube films using a microwave plasma-assisted chemical v...
2007 International Semiconductor Device Research Symposium, 2007
... Engineered Surfaces of Multifunctional and Molecular Diamond for Biosensing Sanju Gupta ... W... more ... Engineered Surfaces of Multifunctional and Molecular Diamond for Biosensing Sanju Gupta ... With the recent development in nanoscience and nanotechnology, carbon-based nanomaterials (eg fullerenes, nanotubes, nanodiamond) are receiving much attention due to their ...
ABSTRACTSevere environmental tolerability is the prime factor in the development of novel space m... more ABSTRACTSevere environmental tolerability is the prime factor in the development of novel space materials exhibiting excellent physical properties accompanied by lightweight, reusability, and multifunctional capabilities. Diamond is known for its reputation being radiation hard besides a range of outstanding properties (electronic, optical, mechanical, and chemical) and hence it is preferable in harsh environments. Carbon nanotubes are also of great interest because of several unsurpassable physical properties and it needs to be shown that they are physically stable and structurally unaltered when subjected to irradiation. Therefore, a family of novel nanocarbons (nanodiamond and nanotubes) films deposited by microwave plasma-assisted chemical vapor deposition (MWCVD) technique was subjected to gamma radiation (1, 5, and 20 Mrads) and to medium energy electron-beam irradiation to study their effects on the microscopic structure and corresponding physical properties to establish prop...
ABSTRACT-Image Enhancement is one of the basic requirements for making an image useful for variou... more ABSTRACT-Image Enhancement is one of the basic requirements for making an image useful for various statistical analysis and particle identification that form the basis of various tests and measurements in Digital Photography, Biomedical Tests and Measurements, ...
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