Graphitic Carbon Nitride Decorated with Iron Oxide Nanoparticles as a Novel High-Performance Biomimetic Electrochemical Sensing Platform for Paracetamol Detection

Design and development of new generation smart sensors for medical applications have gained considerable interest of research community in the recent past. In this work, we propose the fabrication of highly sensitive paracetamol sensors-based iron oxide nanoparticles intercalated with graphitic carbon nitride (g-C₃N₄) (GCN) via insitu chemical synthesis. Structural features of the composites were analyzed through SEM, EDX, XRD, FTIR, and UV-Visible spectroscopic techniques. Presence of iron oxide nanoparticles in GCN, significantly improved the conductivity bare GCN from 16 to 125 S cm^?1 due to extended π–π conjugation and large surface area in the composite system. The GCN-Iron oxide (GCN-FO) nanocomposite has been employed as an electrochemical sensing platform for non-enzymatic detection of paracetamol. The electrochemical studies and cyclic voltammetry (CV) results shows that the GCN-FO composite exhibit superior electrochemical properties due to their lower values of the oxidation and reduction potentials. Electrochemical impedance spectroscopy (EIS) studies indicate decreased charge-transfer resistance for iron oxide doped GCN composite in compare to base GCN. The improved electrochemical sensing performance of modified GCN-FO composite electrode is attributed to the formation heterojunctions between iron oxide nanoparticles and GCN. The modified GCN-FO electrodes were employed for non-enzymatic electrochemical detection of PR. The GCN-FO composite electrode shows excellent sensitivity towards PR with a LOD 0.3 μM. Furthermore, the modified GCN-FO electrodes show excellent reproducibility, selectivity, stability and anti-interference performance. Due to its low-cost fabrication, superior electrochemical sensing performance, these modified GCN-FO electrodes could be a promising material for the detection of paracetamol at low concentrations.

     

Mirror effects on dynamic response of surface-emitting lasers

The effects of longitudinal wave distribution and mirror structures on the small-signal response of surface-emitting lasers are analyzed for the first time. The analysis is based on an improved dynamic model implemented in the transfer-matrix representation. It is shown that for two structures with the same threshold gain and the same internal structure, high contrast mirrors give rise to a higher relaxation oscillation and modulation bandwidth for the same injection level     

Critical link identification and prioritization using Bayesian theorem for dynamic channel assignment in wireless mesh networks

Wireless Networks - Wireless Mesh Networks (WMN) is a key backhaul technology used in 802.11 networks to provide ubiquitous coverage to isolated areas that require high-speed connectivity. The...     

Planning a time-minimal motion among moving obstacles

Motion planning for a point robot is studied in a time-varying environment. Each obstacle is a convex polygon that moves in a fixed direction at a constant speed. The point to be reached (referred to as the destination point) also moves along a known trajectory. The concept of accessibility from a point to a moving object is introduced, and is used to define a graph on a set of moving obstacles. If the point robot is able to move faster than any of the obstacles, then the graph exhibits an important property: a time-minimal motion is given as a sequence of edges in the graph. An algorithm is described for generating a time-minimal motion and its execution time is analyzed.The support of the National Science Foundation under Grants IRI-88-02457 and IRI-90-17393 is gratefully acknowledged. This work is supported in part by the Office of Engineering Research Program, Basic Energy Sciences, of the U.S. Department of Energy, under Contract No. DE-AC05-84OR21400 with Martin Marietta Energy Systems, Inc. and in part by an appointment to the U.S. Department of Energy Postgraduate Research Program administered by Oak Ridge Associated Universities.     

The CN method applied to the stationary problem of particle reflection by a purely scattering or weakly absorbing half-space; extension to the asymptotic time-dependent case

The application of the classical C_N method fails for a pure scattering or weakly absorbing medium. The asymptotic C_N method, in stationary mode, is the way to solve the transport equation in this limiting case, when c is equal or very close to 1. The asymptotic method allows us to obtain the asymptotic time-dependent emergent angular distribution for a given impinging angular intensity at t = 0 whatever c may be. The numerical results for the classical and asymptotic methods are consistent in the overlapping range.     

Bidirectional coroutines

The bidirectional coroutine is introduced as a mechanism for overcoming a shortcoming in the method of specification of the transfer of control between coroutines. An analogy is drawn between subroutines and coroutines by observing that coroutines, like subroutines, should not have to know with whom they are interacting. At present, most coroutine implementations require specific mention of the coroutine being resumed, or use a suspend mechanism in which case one coroutine acts as a slave (the suspending one) and the other as a master. In the second case, the slave need not know the identity of its master while the master must know the identity of its slave. For bidirectional coroutines, a coroutine need not know the identity of its master nor its slave. This is achieved by replacing the suspend primitive with two new primitives — resume master and resume slave.     

Shape approximation using quadtrees

The quadtree representation encodes a 2″ by 2″ binary image as a set of maximal blocks of 1's or 0's whose sizes and positions are powers of 2. With the aid of the quadtree, a hierarchy of approximations to the image can be defined. Several ways of doing this are described. The accuracy of these approximations is empirically evaluated by studying how fast estimates of the first few moments of the image, computed from the approximations, converge to the true values, using a database of 112 airplane silhouettes. Approaches to the problem of fast shape matching using these approximations are also discussed.