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The purpose of this study is to demonstrate the potential of ceramic tile dust (CTD)-derived ZSM-5 zeolite (CZ) and its monodispersed composite with metal oxides (MgO and Fe2O3) in the catalytic pyrolysis of hyphaene thebaica shell (HTS). The HTS was pyrolysed in a Fixed-bed reactor at 400–600 °C, and 100–300 mL/min N2 flowrate. The maximum bio-oil production of 32 % was obtained at 500 °C and 150 mL/min N2 flowrate, with bio-oils containing 50 % acid and octadecenoic acids, as well as esters, phenols, aldehydes, ketones, ethers, aromatics, and hydrocarbons. A carboxymethyl cellulose templating agent was employed for the mesoporous zeolite synthesis from CTD. This resulted in the mesoporous zeolite with a predominant ZSM-5 crystal phase, exhibiting pore diameters ranging from 1.8-6 nm, 229 m2/g surface area and 1145 μmol/g total acidity. The catalytic pyrolysis of HTS was conducted using the ZSM-5 zeolite (CZ) and metal-oxide (MgO, Fe2O3, and Fe2O3/FeO) modified CZ, as monodispersed composite catalysts. Under best thermal pyrolysis conditions, CZ-Fe2O3, CZ-MgO, and CZ-Fe2O3/MgO demonstrated 22–23 % bio-oil yields. Notably, the CZ-Fe2O3/MgO catalyst exhibited the highest hydrocarbon yield at 16 %, while the CZ-MgO favoured the production of phenolics, esters, and alcohols. CZ-MgO also displayed the highest coking level at 7.5 %, indicating faster deactivation than the other catalysts. The synthesised catalysts exhibited remarkable catalytic activity, resulting in a notable improvement in the quality of bio-oils obtained from the intermediate pyrolysis of hyphaene thebaica shells in a fixed-bed reactor.

The design and analysis of a planar ultra-wideband elliptical slotted patch antenna for application in breast microwave radar system is presented in this paper. It is modelled in front of a breast phantom of cylindrical shape. No matching liquid is used in this model. A novel partial ground plane with protrusions on two sides is used for achieving good matching without any coupling medium. For effective signal penetration, a low frequency band of operation is selected. The antenna has a wide impedance bandwidth operating from around 1.8 GHz to 6.9 GHz or higher. A parametric study is conducted to understand the effects of important parameters on the antenna performance and to develop some design guidelines. The fabricated prototype was tested in the presence of a breast phantom. The transmission response of the antenna was also measured, which shows reduced transmission loss compared to a previous study since the antenna is in the air. The measured results are in good agreement with simulated data. This antenna can be used in a microwave imaging system for radar based breast cancer detection, where wide impedance bandwidth is required.

This article presents the design of a planar MIMO (Multiple Inputs Multiple Outputs) antenna comprised of two sets orthogonally placed 1 × 12 linear antenna arrays for 5G millimeter wave (mmWave) applications. The arrays are made of probe-fed microstrip patch antenna elements on a 90 × 160 mm2 Rogers RT/Duroid 5880 grounded dielectric substrate. The antenna demonstrates S11 = −10 dB impedance bandwidth in the following 5G frequency band: 24.25–27.50 GHz. The scattering parameters of the antenna were computed by electromagnetic simulation tools, Ansys HFSS and CST Microwave Studio, and were further verified by the measured results of a fabricated prototype. To achieve a gain of 12 dBi or better over a scanning range of +/−45° from broadside, the Dolph-Tschebyscheff excitation weighting and optimum spacing are used. Different antenna parameters, such as correlation coefficient, port isolation, and 2D and 3D radiation patterns, are investigated to determine the effectiveness of this antenna for MIMO operation, which will be very useful for mmWave cellphone applications in 5G bands.

Energy is a necessity for development but its sustainable production is questionable in most metropolitan settlements in developing countries, particularly Nigeria. The combination of fossil fuel with Municipal Solid Waste (MSW) for electricity generation is justified due to the acute inadequacy of electricity in Nigeria coupled with the abundance of coal. Therefore, this research investigates strategies for electricity generation from coal-MSW mix for Bauchi metropolis, North-Eastern Nigeria. Population and MSW generation for the study area were determined from year 2010 to 2070. In 2020, the population of the metropolis will be over 668,000 people generating more than 195,000 t of MSW. The characterization studies showed high proportion of plastics and other combustibles which makes the MSW a good stock for combustion in turbines. The calorific values were determined for various coal-MSW mix and the results range from 8,762 kJ/kg (0 % coal and 100 % MSW) to 11,044.65 kJ/kg (100 % coal with 0 % waste). The energy production strategies for the metropolis was based on five scenarios (A – E) depending on coal-MSW mixture and time frame. Results showed that Scenario A can produce 16.7 MW (146,719 MWh) of electricity in the year 2020 for the metropolis which gradually increases to 32 MW in the first year of Scenario E. In addition, the economic and environmental evaluations of the scenarios revealed that Scenario A is the most attractive in terms of revenue from electricity but least in revenue from carbon credit. Although, Scenario E generates the least per capita revenue, it was found to be the best in terms of environmental considerations. This research therefore provides flexible mechanisms for the production of energy in urban areas to contain MSW problems and reduce CO2 emission from the use of whole coal.

The detailed design equations and antenna parameters for a directional antenna for breast imaging are presented in this paper. The antenna was designed so that it could be immersed in canola oil to achieve efficient coupling of the electromagnetic energy to the breast tissue. Ridges were used in the horn antenna to increase the operating bandwidth. The antenna has an exponentially tapered section for impedance matching. The double-ridged horn antenna has a wideband performance from 1.5 GHz to 5 GHz (3.75 GHz or 110% of impedance bandwidth), which is suitable for breast microwave radar imaging. The fabricated antenna was tested and compared with simulated results, and similar bandwidths were obtained. Experiments were conducted on breast phantoms using these antennas, to detect a simulated breast lesion. The reconstructed image from the experiments shows distinguishable tumor responses indicating promising results for successful breast cancer detection.

The impact of age-related resistance on the regulation of population dynamics of adult Trichuris suis was investigated in an experimental pig model. Helminth-naive pigs varying in age from five weeks to four years were infected with T. suis to determine susceptibility to infection. Sows had a significantly lower establishment of adult T. suis worms compared with weaner pigs. Adult worm populations were highly overdispersed in both sows and grower pigs contrasted by a more even distribution among weaner pigs. Sows had significantly lower worm fecundities compared to weaner and grower pigs; T. suis from grower pigs, in turn, had reduced fecundity compared to worms in weaner pigs. In conclusion, we provide the first controlled experimental evidence that age-related resistance to T. suis occurs in pigs.

The objective of the study was to follow the course of Trichuris suisinfection in pigs given infective eggs at low (400 eggs), medium (4,000 eggs) and high inoculation dose (40,000 eggs), respectively. Interestingly, despite a 100-fold difference in dose level no significant difference was found in either blood parameters, total faecal egg excretion, fecundity or worm burdens at necropsy 12 weeks post inoculation. The highest and lowest median faecal egg output was found in the medium and high dose group, respectively. With increasing dose level, worm size, establishment and prevalence of T. suis positive pigs decreased while worms were dislocated aborally. In addition there was a highly significant correlation between female worm burden and faecal egg excretion.

Tuberculosis is a multiorgan disease with varied clinical presentations and is reemerging due to increasing immigration and globalization. We present the case of an immigrant female patient who developed acute renal failure with clinical and biochemical features suggestive of lupus nephritis but with a timely renal biopsy showing caseating granulomata in the renal parenchyma consistent with renal tuberculosis. Despite treatment with antituberculosis treatment and resolution of TB on repeat renal biopsy, she remained haemodialysis dependent. We discuss the diagnostic challenges faced in this presentation and also explore possible differential diagnoses. This rare presentation highlights the importance of renal biopsy in the diagnosis and treatment of acute renal failure and the atypical presentation of tuberculosis.

This paper aims to analyze the wave propagation in functionally graded carbon nanotube-reinforced composite (FG-CNTRC) beams placed on a viscoelastic foundation utilizing an improved first-order shear deformation theory (FSDT). The material properties are derived from the mixture rule. Four carbon nanotube distribution patterns are considered in the analysis. The extended Hamilton's Principle is utilized to derive the governing wave equations for the CNTRC beam. A comparison between the present theory results and those in the literature is conducted for validation. The wave dispersion investigation is mainly based on the phase and group velocities. The results illustrate the wave propagation responses for the different CNT configurations. In addition, the influence of the CNTs volume fraction, foundation stiffness parameters, and damping coefficient on the wave characteristics is examined. [ABSTRACT FROM AUTHOR]

This paper investigates the free vibration of functionally graded material (FGM) sandwich plates supported by different boundary conditions and influenced by a three-parameter viscoelastic foundation and hygro-thermal changes. Three types of FGM sandwich plates are studied and discussed, in which the FGM layers vary according to the power law rule and consist of ceramic and metal materials. An efficient and simple four-variable integral higher-order shear deformation theory (HSDT) is employed to model the analytical solution of the considered problem. Hamilton principle is implemented to obtain the plates' governing equations and to derive the eigenvalue equation for the free vibration study. The model is verified by comparing numerical results with previous studies on the vibration of exponentially graded plates. New results are presented in this paper showing the influences of different boundary conditions, hygro-thermal changes, viscoelastic parameters, vibration modes, material exponents, and geometric dimensions. [ABSTRACT FROM AUTHOR]

This work studies the dispersion relations of wave propagation in infinite advanced functionally graded (FG) ceramic-metal plates. A simple integral hyperbolic higher-order shear deformation theory (HSDT), with undetermined integral terms and only four unknowns, is used to formulate a solution for the waves' dispersion relations. The effective functionally graded materials' (FGM) properties follow the power-law with three different types of uneven porosity distributions. The effect of foundation viscosity is investigated by considering the damping coefficient in addition to Winkler's and Pasternak's parameters. The wave propagation's governing equations are derived based on the present integral hyperbolic HSDT using Hamilton's principle. The eigenvalue problem describing the porous FG plate dispersion relations resting on a viscoelastic foundation is analytically determined. The theory accuracy is validated by numerically comparing the results with previously published works. Finally, the influences of gradation power, porosity parameters, and the viscoelastic foundation parameters on wave propagation in an FG plate are examined and discussed. [ABSTRACT FROM AUTHOR]

Autism spectrum disorder (ASD), classified as a developmental disability, is now more common in children than ever. A drastic increase in the rate of autism spectrum disorder in children worldwide demands early detection of autism in children. Parents can seek professional help for a better prognosis of the child's therapy when ASD is diagnosed under five years. This research study aims to develop an automated tool for diagnosing autism in children. The computer-aided diagnosis tool for ASD detection is designed and developed by a novel methodology that includes data acquisition, feature selection, and classification phases. The most deterministic features are selected from the self-acquired dataset by novel feature selection methods before classification. The Imperialistic competitive algorithm (ICA) based on empires conquering colonies performs feature selection in this study. The performance of Logistic Regression (LR), Decision tree, K-Nearest Neighbor (KNN), and Random Forest (RF) classifiers are experimentally studied in this research work. The experimental results prove that the Logistic regression classifier exhibits the highest accuracy for the self-acquired dataset. The ASD detection is evaluated experimentally with the Least Absolute Shrinkage and Selection Operator (LASSO) feature selection method and different classifiers. The Exploratory Data Analysis (EDA) phase has uncovered crucial facts about the data, like the correlation of the features in the dataset with the class variable. [ABSTRACT FROM AUTHOR]

In this article, a compact multiband antenna design and analysis is presented with a view of ensuring efficient uplink/downlink communications at the same time from a single antenna for CubeSat applications. This design shares the aperture of an S-band slot antenna to accommodate a square patch antenna operating in the X-band. Shared aperture antennas, along with an air gap and dielectric loading, provided good gain in both frequency bands. The S-band patch had an S11 = −10 dB bandwidth of 30 MHz (2013–2043 MHz, 1.5%), and the X-band antenna demonstrated a bandwidth of 210 MHz (8320–8530 MHz, 2.5%). The Axial Ratio (<3 dB) bandwidth of the slot antenna in the S-band is 7 MHz (2013–2020 MHz, 0.35%), and it is 67 MHz (8433–8500 MHz, 0.8%) in the case of patch antenna in the X-band. While the maximum gain in the S-band reached 7.7 dBic, in the X-band, the peak gain was 12.8 dBic. This performance comparison study shows that the antenna is advantageous in terms of high gain, maintains circular polarization over a wideband, and can replace two antennas needed in CubeSats for uplink/downlink, which essentially saves space. [ABSTRACT FROM AUTHOR]

This paper presents a low-profile, stub-loaded multi-slot antenna that operates across 850MHz to 4500 MHz. Remarkably, the new design meets the call of covering wideband frequencies used by many 4G and 5G New Radio bands from UHF to C bands. The antenna consists of two wide slots on the ground plane. Each slot comprises a straight segment connected to a larger circular slot. A novel microstrip feed line loaded with dual circular stubs excites the multi-slot antenna. The slots and feed lines are printed on each side of the dielectric substrate. This novel design offers pattern diversion capacity based on port excitation. Two prototypes were fabricated and tested to verify multiple simulation results including bandwidth, isolation, and group delays. A close consistency of measured and simulated results validates the design. Concurrently, good isolation between ports and nearly omnidirectional gain patterns are observed over the band. Further, the form factor of the proposed antenna makes it a suitable solution for modern 4G and 5G handheld devices. [ABSTRACT FROM AUTHOR]

A flat-plate wickless-heat-pipes solar-thermal collector with series condenser-coolers (FHSC-S) is developed. Indoor solar experiments are conducted to investigate the thermal behaviour of the FHSC-S collector. The collector is tested under different experimental parameters (collector tilt angles, water flow-rates, solar irradiance levels, and inlet-water temperatures). This part presents the collector design and details, besides an exergy analysis. The experimental results showed that the collector performed well. The inlet fluid exergy, outflow exergy, and gained exergy are increased with the increment in the inlet temperature. The maximum and average values of the collector’s exergy efficiency are 0.20 and 0.08, respectively. [ABSTRACT FROM AUTHOR]

A hybrid perturbation scheme is used in this article to achieve wide axial ratio (AR) bandwidth and beamwidth from circularly polarized (CP) microstrip patch–ring antennas using a single probe feed. Perturbations in the diagonal corners of a square ring and a square patch arranged in a stacked configuration are introduced to achieve the circular polarization. First, an enhanced AR bandwidth is obtained when a combination of a square ring and a square patch with negative perturbations is used as parasitic and driven elements, respectively. Next, circular polarization with wider AR bandwidth, wider beamwidth, and lower cross-polarization is obtained when a combination of a driven square patch with positive perturbation and a parasitic square ring with negative perturbations, termed as hybrid perturbations, is used. This antenna has a footprint suitable for small satellite applications (e.g., CubeSats) and its operating frequencies cover the allocated S-band downlink frequencies of NASA Deep Space Network and NASA Near Earth Network. [ABSTRACT FROM AUTHOR]

The 4‐anilino‐6,7‐ethylenedioxy‐5‐fluoroquinazoline scaffold is presented as a novel model system for the characterization of the weak NH⋅⋅⋅F hydrogen bonding (HB) interaction. In this scaffold, the aniline NH proton is forced into close proximity with the nearby fluorine (dH,F∼2.0 Å, ∠∼138°), and a through‐space interaction is observed by NMR spectroscopy with couplings (1hJNH,F) of 19±1 Hz. A combination of experimental (NMR spectroscopy and X‐ray crystallography) and theoretical methods (DFT calculations) were used for the characterization of this weak interaction. In particular, the effects of conformational rigidity and steric compression on coupling were investigated. This scaffold was used for the direct comparison of fluoride with methoxy as HB acceptors, and the susceptibility of the NH⋅⋅⋅F interaction to changes in electron distribution and resonance was probed by preparing a series of molecules with different electron‐donating or ‐withdrawing groups in the positions para to the NH and F. The results support the idea that fluorine can act as a weak HB acceptor, and the HB strength can be modulated through additive and linear electronic substituent effects. [ABSTRACT FROM AUTHOR]