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The existing examine is supposed approximately the performance traits of S-Shaped diffusers were explored using Computational Fluid Dynamics (CFD) for Glass fiber reinforced polymer (GFRP), carbon fiber reinforced polymer (CFRP), Perspex (PMMA), and Kevlar reinforced polymer (KFRP). The traits were finished for turning angle 62.5 0 /62.5 0 for consistent round centerline length 600 mm, area ratio (AR) 2, 4, and 6 accordingly, and aspect ratio 2.0 on the intake. Incompressible drift evaluation using renormalized group k-ε model, standard k-ε, and realizable k-ε model. It has been discovered that the total C P value will rise, flow separation will increase, and flow homogeneity on the exit will decrease by way of growing area ratio for Carbon Fiber Reinforced Polymer (CFRP). It is found that for an area ratio 2 and 6 the existing version offers the high-quality performance in terms of C L and C P respectively for Carbon Fiber Reinforced Polymer (CFRP). Overall, CFRP is ideal for high-performance applications (e.g., aerospace, motorsports) despite its cost, while Perspex is suitable for non-critical, cost-sensitive uses. GFRP and KFRP fill the middle ground, offering decent performance at moderate costs.

The present study investigates the fundamental mechanisms of interaction between the propeller wake vortices and an untipped non-lifting wing. The study consists of a comprehensive experimental survey of a reference propeller–wing configuration with a high thickness parameter and is based on time-resolved visualisations and detailed flow and wall-pressure measurements. The experiment was designed to investigate the dynamics of the propeller blade vortices during the approach, encounter and penetration phases of the interaction and downstream of the body. To this end, three different models of the wing were manufactured including a transparent Perspex model that was crucial to simultaneously visualise the evolution of the vortex branches on the pressure and suction side of the body during the penetration phase. The study gains insight into the fundamental underlying mechanisms of the complex interaction between the propeller tip and blade trailing vortices and the wing for different propeller loadings. It is found that, during the encounter and the early penetration phases, tip vortex behaviour is strongly influenced by its interaction with the boundary layer of the wing that is manifested by a non-symmetrical evolution and breakdown of the vortex portions travelling along the pressure and suction sides of the wing. Reconnection between the vortex lines originating within the vortex core and the wing boundary layer maintains the linkage between the pressure and suction side portions of the vortex during the penetration phase and drives their rejoining downstream of the wing.

The mass attenuation coefficient becomes an important parameter to determine the attenuation property of a material towards photons. The study focused on the measurement of mass attenuation coefficients of several phantom materials in comparison to water by using effective energies of kilovoltage X-rays. The mass attenuation coefficient of Perspex®, solid water phantom and paraffin wax regularly used in diagnostic radiology and radiotherapy is measured by using effective energies of 60, 81 and 125 kVp X-rays based on the common diagnostic imaging set ups and compared to water. The results indicated that the mass attenuation coefficients of Perspex®, solid water and paraffin wax are in agreement with water with percentage of discrepancies between 22 and 13%. The percentage differences to water also becoming smaller when higher x-ray energies are used. The results indicated the suitability of the X-ray effective energy method for the measurement of mass attenuation coefficients of materials.

Abstract Cyanobacteria are new sources of value-added compounds but also ubiquitous and harmful microfoulers on marine biofouling. In this work, the isolation and identification of two cyanobacterial strains isolated from Cape Verde and Morocco, as well as their biofilm-forming ability on glass and Perspex under controlled hydrodynamic conditions, were performed. Phylogenetic analysis revealed that cyanobacterial strains isolated belong to Leptothoe and Jaaginema genera (Leptothoe sp. LEGE 181153 and Jaaginema sp. LEGE 191154). From quantitative and qualitative data of wet weight, chlorophyll a content and biofilm thickness obtained by optical coherence tomography, no significant differences were found in biofilms developed by the same cyanobacterial strain on different surfaces (glass and Perspex). However, the biofilm-forming potential of Leptothoe sp. LEGE 181153 proved to be higher compared with Jaaginema sp. LEGE 191154, particularly at the maturation stage of biofilm development. Three-dimensional biofilm images obtained from confocal laser scanning microscopy showed different patterns between both cyanobacterial strains and also among the two surfaces. Because standard methodologies to evaluate cyanobacterial biofilm formation, as well as two different optical imaging techniques, were used, this work also highlights the possibility of integrating different techniques to evaluate a complex phenomenon like cyanobacterial biofilm development. This work assesses the isolation, identification and characterization of two cyanobacterial strains isolated from Morocco and Cape Verde, as well as their biofilm-forming ability at two different surfaces, in a long-term assay under controlled hydrodynamic conditions.

Octopuses have large brains and exhibit complex behaviors, but relatively little is known about their cognitive abilities. Here we present data from a five-level learning and problem-solving experiment. Seven octopuses (Octopus vulgaris) were first trained to open an L shaped container to retrieve food (level 0). After learning the initial task all animals followed the same experimental protocol, first they had to retrieve this L shaped container, presented at the same orientation, through a tight fitting hole in a clear Perspex partition (level 1). This required the octopuses to perform both pull and release or push actions. After reaching criterion the animals advanced to the next stage of the test, which would be a different consistent orientation of the object (level 2) at the start of the trial, an opaque barrier (level 3) or a random orientation of the object (level 4). All octopuses were successful in reaching criterion in all levels of the task. At the onset of each new level the performance of the animals dropped, shown as an increase in working times. However, they adapted quickly so that overall working times were not significantly different between levels. Our findings indicate that octopuses show behavioral flexibility by quickly adapting to a change in a task. This can be compared to tests in other species where subjects had to conduct actions comprised of a set of motor actions that cannot be understood by a simple learning rule alone.

Objective: This work aims to set up the correlation between height and absorbed dose using commercial acrylic dosimeters, through a mapping of the absorbed dose distribution in a panoramic cobalt-60 gamma irradiator. This study is essential for defining a safe limit for stacking boxes having materials subject to gamma irradiation, aiming to maintain service quality and optimize space in the irradiation chamber.   Theoretical Framework: Dosimetry is an important function in radiation processing, where large, absorbed doses and dose rates from photon must be measured with reasonable accuracy. Proper calibration and traceability of routine dosimetry systems to standard are crucial to the success of large-volume radiation processes. It is essential that users perform their own separate calibration for their own instrumentation and conditions of use.   Method: The samples to be irradiated is placing in specific positions, the dose value to be received by each sample is known. Four absorbed dose locations were chosen (1, 2, 3, and 5 kGy). Sixty Amber Perspex 3042 dosimeters from the same batch were used to analyze the correlation between height and absorbed dose. The procedure adopted involved calculating an absorbed dose point in the irradiator that delivers a dose of 2.5 kGy and covers a 24-hour irradiation period. After irradiation, the dosimeters were analyzed with a spectrophotometer at 603 nm to obtain absorbance values.   Results and Discussion: The results showed that the radiation field remains homogeneous up to a height of 1.60 m, up to 2 m from the Co-60 source. It was concluded that the boxes can be safely positioned up to this height without significant variation in the absorbed dose. To achieve the target dose of 2.5 kGy, it is recommended to adjust the distance between the boxes and the radiation source, allowing the absorbed dose to be optimized without compromising the homogeneity of the radiation field. Research Implications: It was concluded that the boxes can be safely positioned up to heights up to 1.60 m at a distance 2 m from the source, without significant variation in the absorbed dose. To achieve the target dose of 2.5 kGy, it is recommended to adjust the distance between the boxes and the radiation source, allowing the absorbed dose to be optimized without compromising the homogeneity of the radiation field.   Originality/Value: This experimental work is important for the quality and reliability of the irradiations performed in this laboratory. Experimental work validates theoretical predictions.

Six different composites of epoxy resin and Carbopol 974p polymer were prepared based on Carbopol 974p polymer concentrations of 0%, 5%, 10%, 15%, 20%, and 25%. The linear and mass attenuation coefficients, Half Value Layer (HVL), and mean free path (MFP) of these composites were determined using single-beam photon transmission in the energy range between 16.65 keV and 25.21 keV. This was carried out by determining the attenuation of ka1 X-ray fluorescent (XRF) photons from niobium, molybdenum, palladium, silver, and tin targets. The results were compared with theoretical values of three types of breast material (Breast 1, Breast 2, Breast 3) and Perspex, which was calculated using a XCOM computer program. The results show that there were no significant differences in the attenuation coefficient values after the consequent Carbopol additions. Moreover, it was found that the mass attenuation coefficients of all tested composites were close to those of Perspex and the values for Breast 3. The HVL and MFP results showed that the E25 sample is closer to the results of the Perspex material with differences of (0.53–1.15%) and (0.51–1.20%), respectively. In addition, the densities of the fabricated samples were in the range of 1.102–1.170 g/cm3, which is in the range of human breast density. A computed tomography (CT) scanner was used to investigate the CT number values for the fabricated samples. The CT numbers of all samples were in the range of human breast tissue (24.53–40.28 HU). Based on these findings, the fabricated epoxy–Carbopol polymer is a good candidate for use as a breast phantom material.

Understanding pore-scale flow and transport processes is important for understanding flow and transport within rocks on a larger scale. Flow experiments on small-scale micromodels can be used to experimentally investigate pore-scale flow. Current manufacturing methods of micromodels are costly and time consuming. 3D printing is an alternative method for the production of micromodels. We have been able to visualise small-scale, single-phase flow and transport processes within a 3D printed micromodel using a custom-built visualisation cell. Results have been compared with the same experiments run on a micromodel with the same geometry made from polymethyl methacrylate (PMMA, also known as Perspex). Numerical simulations of the experiments indicate that differences in experimental results between the 3D printed micromodel and the Perspex micromodel may be due to variability in print geometry and surface properties between the samples. 3D printing technology looks promising as a micromodel manufacturing method; however, further work is needed to improve the accuracy and quality of 3D printed models in terms of geometry and surface roughness.

Purpose The purpose of this study is to achieve lower and lower temperature as infrared sensors works faster and better used for space application. For getting good quality images from space, the infrared sensors are need to keep in cryogenic temperature. Cooling to cryogenic temperatures is necessary for space-borne sensors used for space applications. Infrared sensors work faster or better at lower temperatures. It is the need for time to achieve lower and lower temperatures. Design/methodology/approach This study presents the investigation of the critical Stirling cryocooler parameters that influence the cold end temperature. In the paper, the design approach, the dimensions gained through thermal analysis, experimental procedure and testing results are discussed. Findings The effect of parameters such as multilayer insulation, helium gas charging pressure, compressor input voltage and cooling load was investigated. The performance of gold-plated and aluminized multilayer insulation is checked. The tests were done with multilayer insulation covering inside and outside the Perspex cover. Practical implications By using aluminized multilayer insulation inside and outside the Perspex cover, the improvement of 16 K in cool-down temperature was achieved. The cryocooler is charged with helium gas. The pressure varies between 14 and 18 bar. The optimum cooling is obtained for 17 bar gas pressure. The piston stroke increased as the compressor voltage increased, resulting in total helium gas compression. The optimum cool-down temperature was attained at 85 V. Originality/value The cryocooler is designed to achieve the cool-down temperature of 2 W cooling load at 100 K. The lowest cool-down temperature recorded was 105 K at a 2 W cooling load. Multilayer insulation is the major item that keeps the thermal radiation from the sun from reaching the copper tip.

Conventional colorimetric enzyme-linked immunosorbent assay (ELISA) is a time-consuming laboratory assay that is not very sensitive and consumes a large amount of samples. Herein, the development of a reusable, cost-effective, and eco-friendly poly(methyl methacrylate) (PMMA)/paper hybrid plug-and-play (PnP) device for high-sensitivity immunoassay by analyte enrichment and efficient passing-through washing has been reported. The PMMA device has multiple slots where a pre-patterned paper substrate can be inserted. The sample flows back-and-forth through a low-cost, 3D paper substrate within the PMMA channels, thereby enhancing the amount of analyte adsorbed and dramatically increasing the sensitivity while decreasing the assay time. After the enrichment assay, the paper substrate can simply be pulled out of the device, and the results can be qualitatively viewed with the naked eye or scanned through a simple desktop scanner for quantitative analysis. The paper substrate can be replaced with a new substrate so that the device can be reused. The limits of detection (LODs) of 200 pg/mL for immunoglobulin G (IgG) and 270 pg/mL for hepatitis B surface antigen (HBsAg) were obtained. This IgG assay is at least 10 times more sensitive than commercial ELISA kits. In addition, the PnP ELISA exhibited a significant increase in the linear dynamic range from 3 orders of magnitude in a common paper-based device to a wide range of six orders of magnitude in the PnP hybrid device. This reusable PnP device has great potential for the low-cost yet high-sensitivity detection of infectious diseases, cancers, and other important biomolecules.Bioanalysis: Simple, eco-friendly, portable PnP device for ultrasensitive immunoassaysA reusable, cost-effective, and environment-friendly PnP device has been developed for high-sensitivity immunoassays (biochemical tests that measure proteins or other substances through their properties as antigens or antibodies). Immunoassays are widely used in the diagnosis, screening, and monitoring of diseases. However, such techniques as enzyme-linked immunosorbent assay (ELISA), which are extensively applied in developed countries, are not widely available in developing nations owing to limited funding and lack of skilled manpower. They are also time consuming and lacking in sensitivity. A team headed by XiuJun Li at the University of Texas at El Paso produced a low-cost device using poly(methyl methacrylate) (PMMA or Perspex) that is 10 times more sensitive than commercial ELISA kits. The authors believe that their PMMA device offers considerable potential for application in detecting infectious diseases and cancers in resource-poor settings.