9 research outputs found

    Plasmonic hybrid terahertz photomixer of graphene nanoantenna and nanowires

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    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® 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

    Lightweight ANU-II block cipher on field programmable gate array

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    Nowadays the number of embedded devices communicating over a network is increasing. Thus, the need for security appeared. Considering various constraints for the limited resources devices is very important. These constraints include power, memory, area and latency. A perfect environment for satisfying requirements of security in limited resources devices is lightweight cryptography. A recent lightweight algorithm that has a low area and high throughput which is the ANU-II block cipher. Many technologies like the internet of things (IoT) needed lightweight hardware architectures to provide security for it. In IoT issues like the size of memory, power consumption and smaller gate counts need to take care of by using lightweight cryptography. This paper presents hardware lightweight data path implementation for the ANU-II algorithm using field programmable gate array (FPGA). This paper presents a hardware implementation of a 64-bit ANU-II block cipher. Also, this research presents comparisons based on various design metrics among our data path for the ANU-II cipher and other existing data path designs. The result of the proposed design shows a high throughput of 1502.31, 1951.86, and 2696.47 Mbps. Also, it shows the high efficiency of 7.0201, 31.9977, and 10.6579 Mbps/slice as compared to other ciphers in this paper

    Synthesis, characterization, and antimicrobial evaluation of new Schiff bases derived from vanillic acid conjugated to heterocyclic 4H-1,2,4-triazole-3-thiol

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    A multistep synthesis was established for the preparation of a new vanillic acid-1, 2, 4-1triazole-3-thiol conjugate (4). Finally, several aromatized aldehydes reacted with compound (4) to produce Schiff bases derivatives (5–11). The purpose of this research is to prepare new vanillic acid derivatives with 1, 2, 4-triazole-3-thiol heterocyclic ring structures and to evaluate their antimicrobial activity in a preliminary assessment. Fourier-transform infrared (FT-IR) and proton nuclear magnetic resonance spectroscopy (1H-NMR) were used to verify the structures of the newly synthesized compounds. all the final synthesized compounds (5–11) were tested for antimicrobial activity. The findings of this study demonstrate the viability of synthesizing vanillic acid combined with a 1, 2, 4-triazole-3-thiol ring derivative, which then reacted with various aldehydes to yield several new Schiff bases derivatives. Finally, the presence of an electron-withdrawing group at the fourth position (p- chloro group) of the aromatic ring improves the antibacterial activity of the derivative of the vanillic acid-triazole conjugate. Compound 8 with para chloro substituted Schiff base derivative showed potent activity when compared to other final derivatives but of no activity toward K. pneumonia

    Assessment of the trophic status at Al-Sabil River using the trophic indices in Al-Shinafiya district, Southern Iraq

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    The current study was conducted to determine the quality of the water of Al- Sabil River in Al-Shinafiya district, Province of Al- Diwaniyah, for the period from September 2018 to August 2019. Three sites were selected along the river, a quantitative and qualitative study of the diatoms as well as its indices to assess the quality of water in the river, such as trophic diatom Index (TDI), Trophic State Index (TSI), Diatomic Index (DI), and General Diatoms Index (GDI). The current study was diagnosed about 136 species of diatoms at three sites, where the central diatoms was 12 species while the pannals diatoms reached 124 species, and recorded total numbers of diatoms (35453.8, 29447.2 and 36504.76) cell*310/L, and rates (2954.48, 2453.93 and 3042.06) cells*310/L for the three locations respectively, as shown by the results of the trophic diatom Index(TDI) values ranged from (23.33 to 55.54) and the values of Trophic State Index (TSI) ranged from (0.07 to 0.81) and the Diatomic Index (DI) values ranged from (9.08 to 16.20) and the values of the General Diatoms Index (GDI) ranged from (2.23 to 3.17). It was noted that the water quality was Oligotrophic to Mesotrophic based on TDI and TSI, while its moderate to Good based on DI and GDI, and concluded that the higher the evidence values indicated that the water quality tended to be good, free or low pollution, suitable for living well, and that water was few nutrients, while its low values indicated the deterioration of the water quality in the river.Validerad;2020;Nivå 1;2020-11-18 (johcin)</p

    Hydrogeochemical processes and evaluation of groundwater in Al-Salman area – Iraqi Southern Desert

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    A field survey has been conducted for the study area using the Global Positioning System (GPS) and geological and geomorphological maps of the area. The study area is one of the important areas in Iraq characterized by scarce water resources. The purpose of the study is to determine the hydro-chemical processes and their relationship to groundwater quality carried out in the southwestern desert region of Iraq, where the region lacks extensive studies of water resources. Twenty-eight groundwater samples were collected from wells distributed between the eastern borders of Saudi Arabia and the West Bank of the Euphrates River. For the purpose of hydrogeochemical analyses, the Fetter method was used to collect and examine samples. A large part of the recharge area is located in Saudi Arabia, where the groundwater bearing aquifer represented by the Dammam formation extends to Iraq and Saudi Arabian International borders. The analysis determined the order of cations (Na+ > Ca2+ > Mg2+ > K+) and anions (Cl– > SO42– > HCO3–). High values of the variation coefficient (CV) correspond to the concentration of potassium, sodium and chloride ions (CV: 68.7, 64.7 and 64 respectively). To identify the hydrochemical water facies, the Piper diagram was used. It was found that 53% of the water samples belong to the Na-Cl type and 40% are of the Ca-Mg-Cl type, while the rest of the samples are the Ca-Cl type. To identify geochemical processes, it was found that ion exchange processes via chloroalkaline indices 1 and 2 are prevalent between Ca2+, Mg2+ in the groundwater and Na+, K+ in water bearing rocks. To learn more about the processes that led to the concentration of certain ions, such as sodium, it was found that they tend to be of silicate minerals related to surface runoff of water in recharge areas and carbonic rocks. It was also found that rock / soil-groundwater interaction and evaporation processes were the formal processes in the saturated zone and evaporation in the unsaturated zone are prevalent processes of groundwater ion concentration

    Estimation of Serum Calcium on the Severity and Mortality in COVID-19 Infections in Sulaymaniyah City, Kurdistan Region of Iraq: A Cross-Sectional Study

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    Background: Coronaviruses (COV) are a large family of viruses that cause infections ranging from the common cold to more serious diseases. Mild to severe respiratory illnesses have been linked to coronavirus disease 2019 (COVID-19), which has been classified as a pandemic disease by the World Health Organization. It has been demonstrated that the severity of COVID-19 is highly positively linked with hypocalcemia. Furthermore, calcium imbalances among other electrolytes are linked to the prognosis of COVID-19. Objectives: This study demonstrates a connection between serum calcium levels and COVID-19 as biomedical indicators of COVID-19 infections in Sulaymaniyah city, Iraq. Methods: A cross-sectional study was conducted at Baxshin Hospital for about two months from February 2022 to April 2022. The work was conducted with a total of 40 patients including 22 males and 18 females. The patients&rsquo; ages ranged from 22 to 80 years old. By analyzing a sample from a nasopharyngeal swab and performing real-time reverse transcription-polymerase chain reaction (RT-PCR), all of the patients tested positive as having COVID-19 infection. Serum calcium was determined from the blood samples of the patients in order to evaluate their serum calcium levels. The statistical package for social science (SPSS) was utilized to examine the obtained data. Results: The study revealed a level of calcium between 6.10 and 9.86 mg/dL in male and female patients. The majority of the female patients (61%) displayed low levels of serum calcium, and 33% of the males had a low level of calcium. It can be seen that the highest rate of male patients (66.6%) exhibited a normal level of serum calcium, while 33.3% showed decreased serum calcium. Based on gender and age groups, a statistically significant difference in calcium levels was observed. Conclusions: This study discovered that infection with COVID-19 has some significant laboratory abnormalities, including hypocalcemia, showing that serum calcium might be employed as a prognostic marker in the clinic
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