Influence of Zn doping on microstructure,dielectric, and electric properties in Bi2/3Cu3Ti4O12 ceramic synthesized by the semi-wet method

Journal of Materials Science: Materials in Electronics - Zn-doped and undoped BCTO ceramics (Bi2/3Cu3?xZnxTi4O12, where x?=?0, 0.05, 0.1, and 0.2) were prepared by semi-wet...     

A comprehensive survey of image segmentation: clustering methods,performance parameters,and benchmark datasets

Multimedia Tools and Applications - Image segmentation is an essential phase of computer vision in which useful information is extracted from an image that can range from finding objects while...     

Modeling Fischer–Tropsch kinetics and product distribution over a cobalt catalyst

A detailed kinetic model describing the consumption of key components and product distribution in the Fischer–Tropsch synthesis (FTS) over a 20%Co/0.5Re γ-Al₂O₃ commercial catalyst is developed. The developed model incorporates the H₂O-assisted CO dissociation mechanism developed by Rytter and Holmen and a novel approach to product distribution modeling. The model parameters are optimized against an experimental dataset comprising a range of process conditions: total pressure 2.0–2.2 MPa, temperature 210–230°C, CO conversion range of 10%–75% and feed with and without added water. The quality of the model fit measured in terms of mean absolute relative residuals (MARR) value is 23.1%, which is comparable to literature reported values. The developed model can accurately describe both positive and negative effects of water on the rate kinetics, the positive effect of water on the growth factor, temperature and syngas composition on the kinetics and product distribution over a wide range of process conditions, which is critical for the design and optimization of the Fisher–Tropsch reactors.     

Identification of diluent degradation products in radiolyzed PUREX solvent

Diluent degradation products in gamma radiolyzed Plutonium URanium Extraction (PUREX) solvent were characterized, under the conditions similar to those prevailing in the hot cell for reprocessing. Alkali wash of the degraded solvent followed by vacuum distillation resulted in primary separation. Column separation of the distillation residue followed by spectroscopic analysis using GC-MS and NMR revealed the residue predominantly to be a mixture of dodecan-3-ol, dodecan-4-ol, and dodecan-5-ol in the ratio of 2:1:6, respectively and a mixture of 2-nitrododecane, 3-nitrododecane, 4-nitrododecane, and 5-nitrododecane in the ratio of 2:2:1:1, respectively. The identified compounds were confirmed by synthesizing them individually and comparing their spectral data.     

External temperature sensor assisted a new low power photoplethysmography readout system for accurate measurement of the bio-signs

Microsystem Technologies - This study presents an external temperature sensor assisted a new low power, time-interleave, wide dynamic range, and low DC drift photoplethysmography (PPG) signal...     

Impact of multi threshold transistor in positive feedback source coupled logic (PFSCL) fundamental cell

Analog Integrated Circuits and Signal Processing - In this paper, a new fundamental cell in positive feedback source coupled logic is presented, which is an improvement over the existing...     

Catalyst and its diameter dependent growth kinetics of CVD grown GaN nanowires

GaN nanowires were grown using chemical vapor deposition with controlled aspect ratio. The catalyst and catalyst-diameter dependent growth kinetics is investigated in detail. We first discuss gold catalyst diameter dependent growth kinetics and subsequently compare with nickel and palladium catalyst. For different diameters of gold catalyst there was hardly any variation in the length of the nanowires but for other catalysts with different diameter a strong length variation of the nanowires was observed. We calculated the critical diameter dependence on adatoms pressure inside the reactor and inside the catalytic particle. This gives an increasing trend in critical diameter as per the order gold, nickel and palladium for the current set of experimental conditions. Based on the critical diameter, with gold and nickel catalyst the nanowire growth was understood to be governed by limited surface diffusion of adatoms and by Gibbs–Thomson effect for the palladium catalyst.     

A fast digital chip implementing a real-time noise-resistant algorithm for estimating blood pressure using a non-invasive,cuffless PPG sensor

Microsystem Technologies - A fast digital chip is designed and fabricated successfully to implement the algorithm for estimating blood pressure (BP) in real time by a non-invasive cuffless...