Due to their attractive properties, silver nanowires (Ag-NWs) are newly used as nanoelectrodes in continuous wave (CW) THz photomixer. However, since these nanowires have small contact area, the nanowires fill factor in the photomixer active region is low, which leads to reduce the nanowires conductivity. In this work, we proposed to add graphene nanoantenna array as nanoelectrodes to the silver nanowires-based photomixer to improve the conductivity. In addition, the graphene nanoantenna array and the silver nanowires form new hybrid nanoelectrodes for the CW-THz photomixer leading to improve the device conversion efficiency by the plasmonic effect. Two types of graphene nanoantenna array are proposed in two separate photomixer configurations. These are the graphene nanodisk (GND) array and the graphene bow-tie nanoantenna (GNA) array. The photomixer active region is simulated using the computer simulation technology (CST) Studio Suite<sup>®</sup> for three optical wavelengths: 780 nm, 810 nm, and 850 nm. From the results, we found that the electric field in the active region is enhanced by 4.2 and 4.8 times for the aforementioned configurations, respectively. We also showed that the THz output power can be enhanced by 310 and 530 times, respectively.
The specifications of lubricating oil are fundamentally the final product of materials that have been added for producing the desired properties. In this research, spherical nanoparticles copper oxide (CuO) and titanium oxides (TiO2) are added to SAE 15W40 engine oil to study the thermal conductivity, stability, viscosity of nano-lubricants, which are prepared at different concentrations of 0.1%, 0.2%, 0.5%, and 1% by weight, and also their pour point, and flash point as five quality parameters. The obtained results show that CuO nanoparticles in all cases, give the best functionality and effect on engine oil with respect to TiO2. With 0.1 wt. % concentration, the thermal conductivity of CuO/oil and TiO2/
... Show MoreThis study was conducted at the Research Experimental Station of the College of Agricultural Engineering/University of Baghdad in the Al-Jadiriyah area during the autumn season of 2022. The study aimed to investigate the effect of phosphorus addition and zinc spraying on the nutrient content and root growth of the cabbage. The experiment included two factors: the first factor was phosphorus with four concentrations (P25%, P50%, P75%, and P100%) of the recommended complete fertilizer dose (135 kg P2O5 per hectare), and the second factor was zinc spraying with three concentrations (0, 30, and 60 mg.L-1) of zinc sulfate (ZnSO4). The results showe
Background: Accurate measurement of a patient’s height and weight is an essential part of diagnosis and therapy, but there is some controversy as to how to calculate the height and weight of patients with disabilities. Objective: This study aims to use anthropometric measurements (arm span, length of leg, chest circumference, and waist circumference) to find a model (alternatives) that can allow the calculation of the height and the body weight of patients with disabilities. Additionally, a model for the prediction of weight and height measurements of patients with disabilities was established. Method: Four hander patients aged 20-80 years were enrolled in this study and divided into two groups, 210 (52.5%) male and 190 (47.5%) fe
... Show MoreThis work investigates the properties of polyvinyl alcohol (PVA) nanocomposite films with varying multi-walled carbon nanotube (MWCNT) content, ranging from 2 to 8 wt.%. The films were prepared using a solution casting method and characterized using UV-visible spectroscopy, optical microscopy, X-ray diffraction, and tensile tests. The prepared PVA/MWCNT nanocomposite films exhibited optical band gap values ranging from 3.5 eV to 5.3 eV. XRD analysis confirmed the semi-crystalline nature of these nanocomposites. Mechanical properties, including hardness, yield strength, ultimate tensile strength, and Young's modulus, were enhanced by increasing MWCNT content by up to 8%. Contact angle measurements showed an increase in hydrophobicity with in
... Show MoreA new series of schiff base and aminothiadiazole derivatives of N- substituted phthalimide (I-VI) were synthesized. In this work, the intermediate 4-(1,3-dioxoisoindolin-2-yl)benzaldehyde compound (I), was formed by reaction of 4-amino benzaldehyde with phthalic anhydride in glacial acetic acid(GAA). A series of Schiff bases (IV-VI) was prepared by the reaction of benzidine with compound (I) in ethanol and presence of GAA as a catalyst to form compound (IV) which react with compound (I) and p-nitro benzyldehyde to give compound (V) and (VI) respectively. A new phthalimide thiosemi-carbazone derivative (ll) was prepared by reaction of compound (l) with thiosemi-carbazide HCl in the presence of equimolar amount of sodium acetate. Fina
... Show MoreBackground: Staphylococcus spp. are widely distributed in nature and can cause nosocomial, skin infections, and foodborne illness, and it may lead to severe financial losses in birds by causing systemic infection in numerous organs. Aim: This study was conducted to determine the prevalence of Staphylococcus spp. in humans and birds in Baghdad city. Methods: Seventy-six oral cavity swabs were collected, including 41 from birds and 35 from breeders. All samples were examined by bacteriological methods and identified by using the VITEK technique, the samples were then further studied to test the ability of biofilm formation, and MDR factors and MAR index were tested with the use of seven antibiotics. Results: Among the 76 oral swa
... Show MoreThis study was conducted to detect the relationship between organic content in the sediment of Rivers Tigris and Diyala, at two locations south of Baghdad, with some environmental factors and the benthic invertebrates and values of diversity indices. Monthly samples collected from the area for the period November 2007 to October 2008. Results showed differences in the physical and chemical characteristics of the two sites, Where the annual average in Tigris and Diyala were respectively for: water temperature (19, 20) C°, pH (8, 8), dissolved oxygen (4, 8) mg / l , Biochemical oxygen Demand BOD5 (3,44 ) mg/l, TDS (632,1585) mg / l, TSS (42, 44) mg / l, turbidity (28,74) NTU, and total hardness as CaCO3 (485,823) mg / l ,Sulfat
... Show MoreThis study aims to study some morphological and reproductional characteristics in eleven species of two genera belonging to the family of Asparagaceae, which are Bellevalia Lapeyrouse, 1808 and Ornithogalum Linnaeus, 1753 and the species are: Bellevalia chrisii Yildirim and Sahin, 2014; Bellevalia flexuosa Boissier, 1854; Bellevalia kurdistanica Feinbrun, 1940; Bellevalia longipes Post, 1895; Bellevalia macrobotrys Boissier, 1853; Bellevalia paradoxa Boissier, 1882; Bellevalia parva Wendelbo, 1973; Bellevalia saviczii Woronow, 1927; Ornithogalum brachystachys C. Koch, 1849; Ornithogalum neurostegium Boissier, 1882 and Ornithogalum pyrenaicum Linnaeus, 1753. These species were identified and compared with each other; the results showed th
... Show MoreThe social networking sites have brought about fundamental changes and a qualitative shift in the marketing industry and its strategies. The Iraqi ministries have used this site i.e. Facebook to spread and disseminate values in order to consolidate it in Iraqi society which has witnessed many changes in all aspects of life.
The researcher studies the pages of both ministries to know the values contained in the publications of the pages of these two ministries, the quality of grooming as well as the forms in which these values are marketed.
The researcher uses a survey method and content analysis for the publications of these two pages during the study period starting from January 1, 2
... Show MoreAnatomical changes in internal tissue of stem and leaf when seed and plant treated with acids to enhance growth and development in maize was studied during the spring seasons of 2019 and 2020. Randomized complete block design was used with three replications. Main plots received foliar nutrition treatments, including ascorbic acid (AA), citric acid (CA), and humic acid (HA) at concentrations of 100 mg L−1, alongside HA at 1 ml L−1, with distilled water as the control. Sub-plots underwent corresponding treatments for seed soaking. Results indicated variations in vascular bundle size among treatments, with foliar CA treatment showing superior results in both years, as well as seed soaking in CA and HA. Interaction effects were observed, n
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