Effect of Transient and Steady-State Current on the Photothermal Performance of a UVC-LED

Author(s):  
Hengpeng Wang ◽  
Jun Zou ◽  
Bobo Yang ◽  
Mingming Shi ◽  
Yuefeng Li ◽  
...  
Sensors ◽  
2020 ◽  
Vol 20 (10) ◽  
pp. 2910
Author(s):  
Seyed Mohsen Hashem Zadeh ◽  
Mohammadhosein Heidarshenas ◽  
Mohammad Ghalambaz ◽  
Aminreza Noghrehabadi ◽  
Mohsen Saffari Pour

The present paper aims to investigate the influence of perforated membrane geometry on the performance of biosensors. For this purpose, a 2-D axisymmetric model of an amperometric biosensor is analyzed. The governing equations describing the reaction-diffusion equations containing a nonlinear term related to the Michaelis–Menten kinetics of the enzymatic reaction are introduced. The partial differential governing equations, along with the boundary conditions, are first non-dimensionalized by using appropriate dimensionless variables and then solved in a non-uniform unstructured grid by employing the Galerkin Finite Element Method. To examine the impact of the hole-geometry of the perforated membrane, seven different geometries—including cylindrical, upward circular cone, downward circular cone, upward paraboloid, downward paraboloid, upward concave paraboloid, and downward concave paraboloid—are studied. Moreover, the effects of the perforation level of the perforated membrane, the filling level of the enzyme on the transient and steady-state current of the biosensor, and the half-time response are presented. The results of the simulations show that the transient and steady-state current of the biosensor are affected by the geometry dramatically. Thus, the sensitivity of the biosensor can be influenced by different hole-geometries. The minimum and maximum output current can be obtained from the cylindrical and upward concave paraboloid holes. On the other hand, the least half-time response of the biosensor can be obtained in the cylindrical geometry.


2021 ◽  
Author(s):  
Serafin Tierrafria-Baez ◽  
Priscila M. Calderon-Lopez ◽  
Victor Cano-Valdez ◽  
Brayan K. Aviles-Diaz ◽  
Carlos Rodriguez-Donate ◽  
...  

2021 ◽  
Vol 11 (15) ◽  
pp. 6920
Author(s):  
Oldřich Coufal

Two infinitely long parallel conductors of arbitrary cross section connected to a voltage source form a loop. If the source voltage depends on time, then due to induction there is no constant current density in the loop conductors. It is only recently that a method has been published for accurately calculating current density in a group of long parallel conductors. The method has thus far been applied to the calculation of steady-state current density in a loop connected to a sinusoidal voltage source. In the present article, the method is used for an accurate calculation of transient current using transient current density. The transient current is analysed when connecting and short-circuiting the sources of sinusoidal, constant and sawtooth voltages. For circular cross section conductors, the dependences of maximum current density, maximum current and the time of achieving steady state on the source frequency, the distance of the conductors and their resistivity when connecting the source of sinusoidal voltage are examined.


Sign in / Sign up

Export Citation Format

Share Document