Design of Novel Sensitive Terahertz Biosensors Based on Graphene-Plasmonic Nanostructures

In this paper, four different configurations of sensitive biosensors based on graphene-plasmonic combinations are designed and proposed. The nanostructures are made of graphene, SiO2, aluminum and gold layers on a silicon substrate. Graphene-ring shaped structures with diagonal strips in vertical and horizontal directions are considered in the structures which greatly affect the absorption characteristics (absorption peak value and wavelength). Aluminum layer is used in the structure to prevent the transmission of light throughout some layers and improving the absorption factor. To promote the functionality of the structures, effects of the structural parameters (R1 and R2) and chemical potentials (Ef1, Ef2, Ef3 and Ef4) on the absorption peak-wavelength and its value, are also studied. The four individual configurations with different layers and strip directions demonstrate distinct and different wavelength ranges; structure-1: 45-60 µm, structure-2: 50-70 µm, structure-3: 70-85 µm, and structure-4: 80-100 µm. Thus, they can be utilized for wide categories of applications. Sensitivities of 1500nm/RIU, 2250/RIU, 3750nm/RIU and 4850nm/RIU are obtained for four types, respectively. The proposed structures indicate more sensitivities and they can be used in acceptable sensing characteristics for different applications like hemoglobin and glucose concentrations in blood samples and can be utilized as refractive index bio-sensing sensors.

The Influence of Pillar Displacements on Geodetic Measurements

This paper deals with the effects that displacements of the measuring pillar have on precise geodetic measurements. The changes in the position of the control points on the object or its surroundings can only be determined with well stabilized and stable reference points. These points are usually stabilized with measuring pillars which are not always constructed in an optimal manner. If they are placed in a dark tube with a high absorption factor, solar heating on one side of the pillar can cause the pillar to deflect considerably due to the temperature difference on the two sides of the pillar. This paper presents the influence of such a displacement, if the pillar is a survey point, orientation point, or control point. We show that even small displacement of the survey point can have important influence on all measurements and that the error in some cases significantly increases, e.g., if the standard deviations of the coordinates of the survey point are 1 mm and their covariance is assumed to be zero, the standard deviation of the distance between measured and exact position of the control point exceeds the value of 2.2 mm.

Enhancing algal biomass production and nutrients removal from municipal wastewater via a novel mini photocavity bioreactor

This study presents the use of a novel photocavity reactor in order to intensify the growth rate, biomass and lipid productivity in microalgae. The reactor offers an aseptic approach for better control on growth rate in microalgae.The Absorption Factor (AF), Attenuation Factor (AtF), Modified Fluence Rate (MFR) and water factor of the photo reactor were recorded to be 1.581, 0.267, 0.347 mW/cm2 and 2.072 respectively. The maximum growth rate recorded was 310 mg L−1 inphotocavity reactor. The results clearly indicate that using the stainless steel visible photoreactor can lead to a significant increase in the growth rate (43.3%), productivity of biomass (27-33%) and lipid content (6-8%) in comparison to microalgae cultivated in glass conical flasks (control). COD, total nitrogen, phosphate and bacterial load (colony-forming unit- CFU) were determined in this study. A decrease in COD (180 to 19 mg/l) and CFU (57×109 to 5×101) of wastewater was also recorded in this study.

The development of analytical methods to determine metoclopramide-hydrochloric acid in the standard raw and it compared with pharmaceuticals

The three novel easy, to the prepare and sensitive spectral methods, were used to estimate metoclopramide in both standard and pharmaceuticals. The effective double–electron, was present in the metoclopramide compound helps to interact in an acidic medium with a reagent such as diazetide resorcinol and 8-hydroxyquinoline reagents. The present article was extended to find out three analytical methods with UV-V is the detector. In both A and B methods, two azo-dyes are formed, they are orange-red and red stable and have high water solubility, giving highest absorption values at 415 nm and 485 nm but the C method will depend on a complex colour configuration with the p-benzoquinone reagent, which has a maximum absorption at a wavelength of 285 nm. Beer's law was applied in a range of concentrations between 1 and 10 μg / ml, 2-20 μg / ml and 1-30 μg / ml. The values ​​of the molar absorption factors were (4.1224 × 104, 3.0229 × 104 and 1.7373 × 104) L mol-1cm-1 with a sensitivity of Sandell’s equal to 0.2606 × 10-4, 0.9834 × 10-4 and 0.2568 × 10 - 4 μg cm-2 to methods A, B respectively and LLOD values ​​were 0.255, 0.553 and 0.158 μg / ml to methods A, B and C. LLOQ 0.512, 0.898 and 0.455 μg / ml to methods A, B, C respectively. The constant fixed Kf configuration was also calculated for the colored outputs of the reaction where it was found to be equal to 43.6435 × 108, 54.6261 × 10-8 and 17.29099 × 106 L2 mol-2 to all methods A, B, C respectively. The values ​​of G were calculated based on -43.9293 KJ / mol, -44.3735 and -51.2019. G values, molar absorption factor, Sandell sensitivity, detection limit.

Stagnation Point Flow through a Porous Medium towards Stretching Surface in the Presence of Heat Generation

In this work, the permeable system of a viscous fluid which impacts a porous stretching surface by heat generation, an investigation has been conducted on a steady laminar flow. Governing equations are converted into nonlinear ordinary differential equations by using the similarities and the solutions are obtained by using the shooting technique. The influences of the dimensionless parameters on the momentum and energy equations. Impacts on together flow and heat transfer from porosity, stretching of the medium of the velocity of the surface and heat generation /absorption factor are exhibited through graphs and deliberated.

Study the Optical Properties of Polyaniline-PEDOT Nano Composite

The study includes the recording the absorption and permeability spectra of a combination of polyaniline compound solution with poly(3,4-ethylenedioxythiophene) PEDOT and calculating the absorption factor and other optical constants. These samples were attended to different concentrations (0.01%,0.02%,0.03%) of PEDOT added to polyaniline. The values of absorbance, the refractive index values of pure polymer and its additives are increasing with the increase of the concentrations of these polymer,noting that the increment of absorption coefficient values under the influence of addition caused by increasing density of the solutions as a result of the increased concentrations, that led to the increase of light absorbed because the interaction of the electromagnetic wave and the large molecules of the polymer increases with concentration,the results show that decreasing in the values of transmittance with all concentrations, the values of reflectance are increases with increasing concentration before and after the doping, the results showed decrease energy gap with increasing ratio of doping.