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Hydrogen has emerged as a promising clean energy carrier for automobile applications. Magnesium hydride (MgH2) has garnered significant attention as a potential H2 storage material due to its high capacity and low cost. Nonetheless, its practical use is hindered by unfavorable H2 sorption kinetics and operating temperatures. This study presents a novel approach to enhance the H2 storage properties of MgH2 by adding graphene oxide (GO) supported tin dioxide (cSnO2) nanoparticles. The as-prepared catalysts (GO/SnO2) were synthesized through modified chemical methods followed by ball-milling with MgH2 characterized using various techniques, including X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray and Fourier transform infrared spectroscopy (FTIR). The catalytic effect of GO-SnO2 nanoparticles on MgH2 was investigated through systematic H2 sorption studies as well as thermal analysis. Results demonstrate that the onset temperature for H2 desorption was significantly reduced, and the dehydrogenation kinetics were substantially enhanced. [ABSTRACT FROM AUTHOR]

A triboelectric nanogenerator (TENG) is one of the most significantly innovative microdevices for built-in energy harvesting with wearable and portable electronics. In this study, the forcespinning technology was used to synthesize a nanofiber (NF) mat-based TENG. Polyvinylidene fluoride (PVDF) membrane was used as the negative triboelectric electrode/pole, and chemically designed and functionalized thermoplastic polyurethane (TPU) was used as the positive electrode/pole for the TENG. The electronic interference, sensitivity, and gate voltage of the synthesized microdevices were investigated using chemically modified bridging of multi-walled carbon nanotubes (MWCNT) with a TPU polymer repeating unit and bare TPU-based positive electrodes. The chemical functionality of TPU NF was integrated during the NF preparation step. The morphological features and the chemical structure of the nanofibers were characterized using a field emission scanning electron microscope and Fourier-transform infrared spectroscopy. The electrical output of the fabricated MWCNT-TPU/PVDF TENG yielded a maximum of 212 V in open circuit and 70 µA in short circuit at 240 beats per minute, which proved to be 79% and 15% higher than the TPU/PDVF triboelectric nanogenerator with an electronic contact area of 3.8 × 3.8 cm2, which indicates that MWCNT enhanced the electron transportation facility, which results in significantly enhanced performance of the TENG. This device was further tested for its charging capacity and sensory performance by taking data from different body parts, e.g., the chest, arms, feet, hands, etc. These results show an impending prospect and versatility of the chemically functionalized materials for next-generation applications in sensing and everyday energy harvesting technology. [ABSTRACT FROM AUTHOR]

The design analysis and prototype of a compact 8×10-mm2 planar microstrip line-fed patch antenna on a readily available, low-cost, reinforced-fiberglass polymer resin composite material substrate is presented in this article. The proposed compact-size antenna has been configured and numerically analyzed using the finite element method-based three-dimensional full-wave electromagnetic field simulator. The optimized design of the antenna has been fabricated on a printed circuit board (PCB), and experimental results have been collected for further analysis. The measurement results affirm the fractional impedance bandwidths of (return loss of less than -10 dB) of 38.78% (2.03–2.98 GHZ) and 16.3% (5.38–6.35 GHz), with average gains of 2.52 and 3.94 dBi at both lower and upper bands, respectively. The proposed dual resonant antenna shows the radiation efficiencies of 91.3% at 2.45 GHz and 87.7% at 5.95 GHz. The stable and almost symmetric radiation patterns and performance criteria of the antenna can successfully cover IEEE 802.11b/g/n, Bluetooth, WLAN, and C-band telecommunication satellite uplinks.

ABSTRACT This is the first report on the parasites of blood cockle Anadara granosa from the Straits of Malacca. For a histopathological survey, samples were collected for 13 mo from [...]

The current study was undertaken to investigate the ovarian cycle of freshwater pearl mussel, Lamellidens marginalis (Lamarck, 1819) collected monthly from a rearing pond in Bangladesh. Gonadal maturation was determined from 2 to 3 mm thick slices of dorso-ventral section cut from the middle of the mussels for histology. The overall male-female sex ratio, 1:1.08 did not deviate significantly from the 1:1 ratio as expected (2-test). Lamellidens marginalis females exhibited a prolonged spawning period from February to November when water temperature remains above 22 °C. Oogenesis occurred round the year although the majority of the females were in early and late-developing stages during January and February. Four distinct peaks in maturity indices (MIs) of L. marginalis females were noted during October, February, June and August when most of the females were ripe and ready for spawning. Condition indices (CIs) ranged from 0.42 ± 0.23 (September 2016) to 0.85 ± 0.25 (October 2015) by mean (± SD) exhibiting five peaks over 12-month study period. Further study should be designed to investigate the timing and brooding pattern of this freshwater unionid species. [ABSTRACT FROM AUTHOR]

SUMMARY Enhancing electromagnetic research on prior light bend mechanisms is a significant issue for composite material phenomena, and one that is not available in nature. The unit cell of metamaterial can be revised, such that it is significantly smaller than the free space of the wavelength. It is essential to extend the appropriate retrieval process to measure electrical and magnetic responses to the backward wave propagation and dispersion diagram characteristics. In this paper, we propose a retrieval process inversion response between known and unknown parameters of the lumped unit-cell circuits that optimizes the best fit parameters. By utilizing the optimization of particle swarm techniques, we provide appropriate values of periodic unit cells of CRLH transmission line circuits that matched with the microstrip implementation model. The group velocity of the wave is indicated in the parallel direction, whereas the phase velocity is in the anti-parallel direction. The dispersion diagram displayed a specifically left-handed and right-handed medium, and a tiny band gap appeared in the attenuation medium. The constitutive parameters of dielectric permittivity, permeability, and refractive index were obtained from the periodic composite transmission line circuits. [ABSTRACT FROM AUTHOR]