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A Cross Sectional Study on the 24 – Hour Variation of Fungal Pollution in the Atmosphere of Erbil City, Iraq
Get PDFAirborne fungi are an important part of aerobiological particles; this group includes several etiologic fungi for humans, animals, and plants. Meteorological parameters as well as plantations are actively influencing the density of outdoor airborne fungi. The current study followed the plate exposure method to collect bihourly air samples for 3 days between April 22 and July 7, 2023. The site of sample collection is 15 meters high in the centre of Erbil city. Sabouraud’s dextrose agar was used. Plates were exposed for 15 minutes from 7 a.m. to 5 a.m. the following day. Plates were kept at lab temperature for 3 weeks and examined daily for visible fungal growth. Fungi were morphologically identified at the genus level. A total of 322 colonies belonging to 10 identified genera, as well as sterile mycelia SM, sclerotia bodies, chlamydospore colonies, and creamy yeast colonies, were Hyphomycetes, which represented 6 genera, Ascomycetes 2, Zygomycetes, and Basidiomycetes, one for each.SM group showed the highest frequency (F% =48.2%) and occurrence (O% =100%). Aspergillus spp. has the second incidence level (F=12.7% and O%=91.6%) followed by Alternaria sp. (F=9.3% and O= 25%).  
Evaluation Of Bioactive Compounds in Desmidorchis Indica Stem Extract Using Spectroscopic and Chromatographic Techniques
No full textDesmidorchis indica is a small fleshy herbs and umbels terminal belonging to the Apocynaceae family. Extraction is the first step of any medicinal plant study, plays a significant and crucial role on the final result and outcome. In the present study to investigate the qualitative analysis of different extracts (aqueous, ethanol, hexane, hydro-ethanolic and petroleum ether) of Desmidorchis indica stem. Among the various extracts, the hydro-ethanolic extract of Desmidorchis indica stem contains a higher concentration of phytochemicals than other extracts and is used for subsequent studies. The UV-VIS spectroscopy revealed that the characteristic peak indicates the presence of various phytochemicals in the extract. The results of FTIR analysis showed the presence of alcohol, phenol, alkynes, alkenes, aromatic, carboxylic acid, aromatic and aliphatic amines groups in Desmidorchis indica stem extract. HPLC analysis of the hydro-ethanolic extract of Desmidorchis indica stem revealed that the presence of kaempferol, quercetin, epigallocatechin and hypersoide. Thirty compounds were identified in extract of Desmidorchis indica stem by GC-MS analysis. The prevailing compounds are n-hexadecanoic acid, 1-octadecanol, cis-11-eicosenoic acid, heptadecanoic acid, oleic acid, octadecanoic acid, 12,15-octadecadiynoic acid, methyl, 9-octadecenoic acid, eicosanoic acid, 2-methyl-z,z-3,13-octadecadienol, di-(9-octadecenoyl)-glycerol, hexadecanoic acid, 2,3-dihydroxypropyl ester and docosanoic acidwere found in this Desmidorchis indica stem. Overall, it can be concluded that Desmidorchis indica stem is a rich source of phytochemicals confirmed through qualitative, quantitative, spectroscopic and chromatographic techniques
The Design of the Speed Control System of Supercharger Using Microcontroller
Get PDFThe cruise control system regulates the car's speed, focusing on simulating and assessing the air compressor's speed control within the engine speed control system. Comprising a microcontroller PIC30 main board, H-Bridge DC motor drive board, encoder, 12V DC motor, supercharger, and PC interface with MATLAB and Simulink, the system aims for efficient speed control. Simulation results showcase the impact on DC electric motor speed control, emphasizing clarity and stability. The study outlines distinct outcomes: 1) Deactivation of the control system. 2) Activation at 1100 rpm. 3) Operation at 1200 rpm. 4) Functioning at 1400 rpm. Observations reveal that without the air compressor, the system struggles to control rotational speed. Conversely, with the control system engaged, consistent average errors of 0.63% occur across the three specified speeds. The setting time remains under 2 seconds. Subsequently, the control system autonomously readjusts the speed to the predefined specifications. The research highlights the system's effectiveness in achieving stable speed control, offering insights into its practical application within automotive engineering
Application of PID Control System in Mecanum Wheelchair
Get PDFThis research centers on the design and implementation of a control system for an electric wheelchair equipped with Mecanum wheels. The study details a comprehensive research methodology starting with the creation of a block diagram to guide system design, hardware selection, and overall implementation. The electric wheelchair system incorporates power resources, input devices, and energy output mechanisms, utilizing a 24 VDC battery and a joystick with a 10K ohm potentiometer connected to an Arduino Due microcontroller. The operational workflow of the system is defined, enabling the wheelchair to respond to joystick commands for forward, left turn, right turn, and other movements. A PID control system is employed to regulate motor movement, enhancing control precision. The Cohen-Coon tuning method is used to determine the PID controller's gain, ensuring efficient closed-loop control. Results from PID controller experiments under P control and PD control are presented, demonstrating the system's responses for different gain values. Optimal performance is observed with a Kp value of 80 and Kd value of 1.2, showcasing improved response speed, reduced rise time, enhanced setting time, and lower percent overshoot. In conclusion, the combined proportional and derivative control system, specifically with Kp = 80 and Kd = 1.2, proves to be effective in enhancing the Mecanum wheelchair's performance. This study provides valuable insights into precise parameter adjustments for optimal control in Mecanum wheelchair applications
A Model Study on the Effects of n-Mesons on Thermodynamics of Strongly Interacting Systems
No full textProperties of strongly interacting matter are quite well-described by the Polyakov loop enhanced Nambu-Jona—Lasinio (PNJL) model as it incorporates two important symmetries. However, discrepancies in low temperature domain remain unless hadronic effects are entwined. Here we have tried to observe the effect of lowest lying hadrons i.e. ?-mesons (pions) considering their medium-dependent masses for zero chemical potential. The thermodynamic quantities now show satisfactory matches with existing lattice QCD and HRG results over the finite temperature window of interest
Performance of PES Membrane Contactor on the Separation of Dilute Acetic Acid from Aqueous Forms
No full textAbstract: The azeotropic characteristics of acetic acid between water make its separation from its aqueous phase essential. Many methods are studied for separating such a mixture. Solvent extraction using membrane contactors can increase the contact surface area. The dilute aqueous acetic acid extraction with the solvents petroleum ether and diisopropyl ether in a Poly Ether Sulfone (PES) hollow fiber membrane contactor was studied. The solvents and membrane extraction abilities are evaluated by exchanging the fluids on the shell and tube sides based on the distribution coefficients and total mass transfer coefficient at various flow rates. The findings show that when the solvent flow is increased, whether on the shell side or the tube side, the concentration of acetic acid increases in its solvent phase. As the shell side Reynolds number increased, it was noticed that the distribution coefficient value also increased. Both solvents' extraction ability was minimal, but diisopropyl ether gave better results when compared with the petroleum ether in terms of distribution coefficient. Three film resistance parameters in the series model have determined the overall mass transfer coefficient. The Reynolds number values showed that the mass transfer occurs in a laminar zone. Changes in the petroleum ether's Reynolds number on the tube side resulted in a maximum mass transfer coefficient of 11.41x10-6 m/s. Data on such hydrodynamics studies on membrane solvent extraction can help recover value-added material studies.
Keywords: Membrane solvent extraction, PES membrane, Acetic acid, DIPE, Petroleum ether
Optimization and Characterization of Friction Welded Joint between A6061 Tube Plate and ASTM A106 Grade B Steel Tube Using Taguchi Method
Get PDFFriction welding of tube to tube plate has gained momentum due to its ability to join dissimilar metals, particularly those that are difficult to weld using traditional welding techniques. This paper aims to explore the influence of major parameters like rotational speed of the tool, shoulder diameter, and feed rate on mechanical properties such as pull strength and microstructural features of A6061 aluminum alloy and ASTM A106 Grade B steel in which welds joined them. An optimal selection of parameters was obtained through Taguchi L9 orthogonal array to achieve maximum pull strength. Results indicated that 1400 rpm for the tool rotational speed with a shoulder diameter of 40mm and a feed rate of 1.2 mm/min gave rise to solid connections. At the interface between welds, SEM studies demonstrated refined grain structure without any intermetallic compounds indicating good bonding between two materials. The XRD analysis showed no formation of intermetallic phases as evidenced by uniform distribution of elements across the interface region confirmed by EDS results. These findings imply that the chosen process variables effectively increase joint strength and ensure a strong weld is formed in FWTPET processes, which could lead to improved industrial applications where high-performance joints for dissimilar metals are needed
E-Learning As A Study Methodology in Primary Education Students: A Bibliometric Study in Scopus Between 2018-2022
No full textThe objective of this study was the analysis and quantification of the scientific literature from the Scopus database about the state of the literature regarding e-learning as a study methodology in primary education students during the period 2018-2022. Thus, the search was carried out through the combination of words "e-learning", "primary student". Likewise, the search filters were applied: Open access and the temporal criteria of 2019-2022, giving a total result of 39 studies that were exported in the Bibtex format for later reading with Cran-R; After applying the inclusion and exclusion criteria, 30 articles were selected as part of the review. Among the results, it was identified that 2021 and 2022 were the years with the highest scientific production. Regarding the productivity of authors, it was found that 3 authors have presented a continuity with the topic studied. On the other hand, the relationship between the keywords of the author, the authors and the affiliations included was interpreted. The frequency of words showed that the keywords with the highest index are "constructivist web-based learning" and "critical thinking". The countries with the highest production were Indonesia and China. The citations were then analyzed, and the studies with the highest citation index present (n=31) and (n=10)
A Review of Microfiltration Membrane in Separating Folic Acid from Fermented Dark Green Leafy Vegetables (DGLVs), Legumes, Beans, and Cereal for Nutraceutical Application
No full textDGLVs (spinach, broccoli), legumes (soybean, mung bean, kidney bean), and cereal (corn) are well recognized for human health benefits due to the presence of natural folate (vitamin B9) with essential micronutrients. Folate is among the most unstable vitamins for the normal functions of the human body. The recent development of membrane-based methods for the separation of folic acid (FA) is reviewed from the selected literature and covers the result of significant research that has been performed in the last five years on the use of the microfiltration (MF) method. This is coupled with the fermentation process to support and achieve separation or recovery of FA from their selected plant-based food source. The nixtamalization, fermentation, separation, and purification of DGLVs, legumes, and beans, as well as corn, were conducted using the MF (pore size 0.15 µm) membrane separation method. The results showed that the MF membrane was able to separate FA components in permeate from fermented spinach and broccoli, soybean, mung bean, kidney bean, and corn, namely 7.14 and 3.79, 197.00, 325.37 and 242.93, and 121.10 µg/mL, respectively. Meanwhile, FA content in retentate from fermented spinach and broccoli, soybean, mung bean, kidney bean, and corn was 58.90 and 28.10, 362.07, 254.07 and 506.07, and 212.84 µg/mL, respectively. The applications of membrane techniques were used as an alternative to some unit operations in the solving of separation issues as well as the development of selected new fermented plant-based food sources. The contemporary pressure-driven membranes, such as MF, and the main applications were related to pre-treatment, selected fermented plant-based food sources, and alternative technology for extending the shelf life of natural folate. The utilization of MF membranes in the nutraceutical field holds significant promise, particularly in the creation of value-added products from minor compounds
Evaluation in Genetic Variation of Krachai by Sequence Related Amplified Polymorphism (SRAP) and Random Amplified Polymorphic DNA (RAPD) Techniques
No full textKrachais are local name of Thai herb which are identified within 2 genera, namely Bosenbergia (white or red krachai) and Kaempferia (black krachai). The rhizome of Bosenbergia rotunda (L.) Mansf. contains major aromatic compounds against COVID19 but its many morphological characteristics such as leaves, stems and rhizome are like other species in same genus or family. In this study, a total of 13 accessions containing 5 samples of B. rotunda, 2 samples of Boesenbergia spp. and 3 samples of Kaempferia parviflora including 3 samples of other species in same family as outgroups were analyzed and clustered using sequence-related amplified polymorphism (SRAP) and random amplified polymorphism DNA (RAPD) markers. The results showed that 8 SRAP primers (M1E1, M1E2, M1E7, M2E10, M3E9, M5E1, M5E2 and M6E10) could generate 79 polymorphism bands with an average of 92.15% whereas a total of 5 RAPD primers (OPY04, OPY02, OPY04, JAT11 and JAT12) could give 64 polymorphisms with 100% as a percentage of the polymorphism band. The PIC of the SRAP marker (0.470) has a higher value than the RAPD marker (0.264). The highest similarity coefficients within genus Boesenbergia of 1.000 and 0.952 were obtained from SRAP and RAPD markers, respectively. The UPGMA dendrogram of SRAP and RAPD information among krachai presented 2 and 4 groups, respectively. The cluster of Boesenbergia was separated from K. parviflora and other species in same family. Furthermore, the results also pointed that Boesenbergia sp. from Phayao is in correct genus and is B. pandurata (Roxb.) Schltr. because of having red leaf while Boesenbergia sp. from Chiang Rai showed confusion between SRAP and RAPD data. It was concluded that SRAP and RAPD have great potential for the study of genetic diversity of Boesenbergia and other species in family Zingiberaceae