Abstract: Despite the distinct features of the continuous wave (CW) Terahertz (THz) emitter using photomixing technique, it suffers from the relatively low radiation output power. Therefore, one of effective ways to improve the photomixer emitter performance was using nanodimensions electrodes inside the optical active region of the device. Due to the nanodimension sizes and good electrical conductivity of silver nanowires (Ag-NWs), they have been exploited as THz emitter electrodes. The excited surface plasmon polariton waves (SPPs) on the surface of nanowire enhances the incident excitation signal. Therefore, the photomixer based Ag-NW compared to conventional one significantly exhibits higher THz output signal. In this work, the effect of Ag-NWs dimensions and number on the incident optical field is investigated by utilizing the Computer Simulation Technology (CST) Studio Suite. The simulation results show that increasing Ag-NWs length to SPP propagation length ratio plays a significant role on the incident field increment due to its effect on reducing the SPP propagation losses. The increment of Ag-NWs number and length in the nanoelectrodes based photomixer can contribute to increase the electric field in the active region by 1.5 times at the longer excitation wavelength (850 nm). As a result of this increment, the THz output power and the conversion efficiency are expected to be enhanced by a factor of five
<span lang="EN-GB">Transmitting the highest capacity throughput over the longest possible distance without any regeneration stage is an important goal of any long-haul optical network system. Accordingly, Polarization-Multiplexed Quadrature Phase-Shift-Keying (PM-QPSK) was introduced lately to achieve high bit-rate with relatively high spectral efficiency. Unfortunately, the required broad bandwidth of PM-QPSK increases the linear and nonlinear impairments in the physical layer of the optical fiber network. Increased attention has been spent to compensate for these impairments in the last years. In this paper, Single Mode Fiber (SMF), single channel, PM-QPSK transceiver was simulated, with a mix of optical and electrical (Digi
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The main objective of this research is to find out the effect of deviation in the aggregate gradients of asphalt mixtures from the Job Mix Formula (JMF) on the general mixture performance. Three road layers were worked on (wearing layer, binder layer, and base layer) and statistical analysis was performed for the data of completed projects in Baghdad city, and the sieve that carried the largest number of deviations for each layer was identified. No.8 sieve (2.36mm), No.50 sieve (0.3mm), and 3/8'' sieve (9.5mm) had the largest number of deviations in the wearing layer, the binder layer, and the base layer respectively. After that, a mixture called Mix 1, was made. This mixture was selected from a number of completed mixtures, and it
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In this research, salbutamol sulphate (SAS) has been determined by a simple, rapid and sensitive spectrophotometric method. Salbutamol sulphate in this method is based on the coupling of SAS with diazotized ρ- bromoaniline reagent in alkaline medium of Triton X-100 (Tx) to form an orange azo dye which is stable and water-soluble. The azo dye is exhibiting maximum absorption at 441 nm. A 10 - 800 µg of SAS is obeyed of Beer's law in a final volume of 20 ml, i.e., 0.5- 40 ppm with ε, the molar absorptivity of 48558 L.mol-1.cm-1 and Sandell's sensitivity index of 0.01188 µg.cm-2. This new method does not need solvent extraction or temperature control which is well applied to determine SAS in d
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Bathyplectes curcurlionis (Thomson) is the sole parasitoid encountered in west Baghdad parasitising larvae of alfalfa weevil Hypera postica (GylIenhal). Percent of parasitisation did not exceed 8% in 1989 and 1990 and overall rate of parasitisation was 5%. Additional reduction in percent of parasitisation caused by presence of the fungal pathogen Erynia phytonomi. High survival percent of weevil's larvae under the study conditions explains why this insect is a key pest of alfalfa. Suggestions were made to inhance the role of B. curcurtionis in controlling the weevil.
This study aims to evaluate drinking water quality at the Al Wahda plant (WTP) in Baghdad city. A conventional water treatment plant with an average flow rate of 72.82 MLD. Water samples were taken from the influent and effluent of the treatment plant and analyzed for some physicochemical and biological parameters during the period from June to November 2020. The results of the evaluation indicate that treated water has almost the same characteristics as raw water; in other terms, the plant units do not remove pollutants as efficiently as intended. Based on this, the station appears to be nothing more than a series of water passage units. However, apart from Total dissolved solids, the mean values of all parameters in the study were
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Background: 37% phosphoric acid (PA) is the traditional enamel etching technique prior to bracket adhesion, yet it has been implicated in numerous enamel injuries. The purpose of the current study was to create a calcium phosphate (CaP) etching paste in a simplified capsule formula that can underpin clinically adequate bracket bond strength without jeopardizing the integrity of enamel upon the debracketing procedure. Materials and Methods: micro-sized hydroxyapatite (HA) powder was mixed with 40% PA solution to prepare experimental acidic CaP paste. Sixty human premolars were assigned into two groups of 30 each. Enamel conditioning was accomplished using 37% PA-gel for control group and CaP paste for e
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