Sensitivity in Nanomechanical Pedestal MEMS Cantilever

Nanomechanical resonator-based sensing devices are used in medical diagnostics based on their high-frequency dynamic behavior. Cantilevers fall into the category of Nanomechanical resonators. It also resembles a resonator whose shape is like that of a nanowire clamped at one end. As the surface-to-volume ratio of a nanowire resonator increases due to scaling down, surface stress plays a crucial role in the mechanical behavior of a resonator. Piezoresistive MEMS cantilevers are used for vapor phase analysis of volatile compounds and gas. Studies were done to address the mass sensitivity issues and fractures associated with bioceramic and nanocomposite coatings-based cantilever resonators. The studies show how the sensing performance can be determined or tuned. Nanomechanical studies of thin films of SiCN on silicon were performed. The sharpness of the tip was found to have an influence on the tip-sample conduction mechanism useful for MEMS applicationsComment: 16 pages, 6 Figure

Structural and Optical Properties of Ni and Zn co-doped Copper Oxide nanoparticles

Ni doping in CuO showed successful replacement of Cu+2 ions by Ni+2 ions. Evidence of strain being developed due to doping was seen. Change in crystallite size was observed depending upon the role of Ni as a nucleating center. Intensity variations in absorption and emission spectra were observed which were related to the amount of defects or formation of new phases in the materials. A wide absorption window was observed due to exciton. A change in band gap was observed corresponding to the change in particle size. Zn doping in CuO caused a variation in crystallite size and incorporated defects which had effect on the optical properties. A change in band gap due to defect generated energy levels as well as quantum size effect was seen

Role of Mn ions in altering the morphology and defects in NiO for photocatalytic and energy Storage Applications

Nickel Oxide having many technological applications was doped with Manganese. The ability of Mn to exist in many oxidation states when incorporated in lower concentration further enhanced the properties of NiO as observed through XRD, UV and PL studies. The generation of vacancies, excitons and lattice vibrations got altered effecting the band gap. Evidence of changes in particle shape was also found. The mechanism behind these phenomena which have technological importance in terms of photocatalysis and energy storage devices discussed

Analysis of Raman spectra with surface and nanocrystalline growth in carbon nitride thin films with nitrogen flow rate

Raman spectroscopy of amorphous hydrogenated carbon nitride (a-C: H: N) films deposited by PECVD respectively were studied. The three stage Ferrari Robertson model was used to explain the structural modifications taking place. A competition between the cluster size growth and clustering itself was identified. A graphene to graphane conversion leading to hydrogen storage possibility in the films has been discussed. Higher nitrogen concentration also led to smoothening of the films. The growth of nanocrystallites took place which was evident through XRD

Stress distribution variations during nanoindentation failure of hard coatings on silicon substrates

Regarding quality inspection of technologically important nanocomposite hard coatings based on Ti, B, Si, C, and N and bioceramics such as hydroxyapatite that are used in small-scale high-precision devices and bio-implants, it is essential to study the failure mechanisms associated with nanoindentation, such as fracture, delamination, and chipping. The stress imposed by the indenter can affect the fracture morphology and the interfacial fracture energy, depending on indenter shape, substrate type, crystallographic properties, pre-existing flaws, internal micro-cracks, and pre-strain. Reported here are finite-element-based fracture studies that provide insights into the different cracking mechanisms related to the aforementioned failure process, showing that the fracture morphology is affected by the interaction of different cracking events. The interfacial fracture energy, toughness, and residual stress are calculated using existing models with minor adjustments, and it is found that increasing the indenter sharpness improves the shear stress distribution, making the coating more prone to separation. Depending on the prevailing type of stress, the stress distribution beneath the depression results in either crack formation or a dislocation pile-up leading to strain hardening. Different forms of resistances resulting from the indentation process are found to affect the tip–sample conduction, and because of its stronger induced plasticity than that of a Berkovich indenter tip, a sharper cube-corner tip produces more resistance

Bioceramics for medical applications: a computational view

Bio ceramics have enormous applications in the medical field as being used as implants. The base material in bioceramics is mostly calcium phosphate which comes in the form of hydroxyapatite (HAp) or Beta-tricalcium phosphate (β-TCP). The other materials are silica and alumina. The different blends of these bioceramics as well as bioglass are in use for medical implants. The use of simulation and modeling in determining and analysing the structure and function of these bioceramics is used for developing implants, scaffolds, and prosthetics as well as for analysing complex molecular interactions. The use of different molecular dynamics modeling techniques, Density Functional Theory, Finite Element Modeling, Artificial Neural Networks, etc is done in this regard. The results of these modeling and simulations are used for bone grafting, making scaffolds, making dental implants, healing damaged bones, 3D modeling, stress analysis, As removal, nanoindentation, etc. Some software like GROMACS, MEGACELL, and ANOVA is used for this purpose. Hydroxyapatite (HAp) was prepared from egg shells by various routes using hexane and acetic acid followed by heat treatment. Hap has a wide application in water treatment by removal of metal ions. XRD of the samples showed use of acetic acid followed by high temperature sintering leads to formation crystalline phases of HAp. Strong evidence of CaCO3 in calcite phase was obtained in other samples

Abstracts of National Conference on Biological, Biochemical, Biomedical, Bioenergy, and Environmental Biotechnology

This book contains the abstracts of the papers presented at the National Conference on Biological, Biochemical, Biomedical, Bioenergy, and Environmental Biotechnology (NCB4EBT-2021) Organized by the Department of Biotechnology, National Institute of Technology Warangal, India held on 29–30 January 2021. This conference is the first of its kind organized by NIT-W which covered an array of interesting topics in biotechnology. This makes it a bit special as it brings together researchers from different disciplines of biotechnology, which in turn will also open new research and cooperation fields for them. Conference Title: National Conference on Biological, Biochemical, Biomedical, Bioenergy, and Environmental BiotechnologyConference Acronym: NCB4EBT-2021Conference Date: 29–30 January 2021Conference Location: Online (Virtual Mode)Conference Organizer: Department of Biotechnology, National Institute of Technology Warangal, Indi