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In this manuscript, we proposed the split ring resonator loaded multiple-input multiple-output (MIMO) antenna design for the frequency range of 1 and 25 GHz. The proposed antenna is numerically investigated and fabricated to analyze the different antenna parameters. We provided statistics on a wide range of antenna parameters for five different designs, including a simple circular patch antenna, a single-split-ring antenna, and a double-split-ring antenna. Reflectance, gain, directivity, efficiency, peak gain, and electric field distribution are all analyzed for all proposed antennas. The maximum achievable bandwidth is 5.28 GHz, and the double-split-ring resonator structure achieves this with a return loss of -20.84 dB. The radiation patterns of all the antenna with different port excitation conditions are presented to identify the behavior of the antenna radiation. We found the effect of the split-ring resonators to form radiation beams in different directions. We found the maximum and minimum half-power beam widths of 75° and 2°, respectively, among the different antenna designs. It was found that the split-ring resonator geometries in patch antenna convert wide-beam antenna radiation patterns to several narrow-beam radiation patterns. We found that each antenna's bandwidth, gain, and return loss performance significantly differs from the others. Overall, the proposed results of the antenna may apply to a wide range of communication applications, including those for Wi-Fi, WiMAX, and 5G.
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http://dx.doi.org/10.3390/mi13122161 | DOI Listing |
MAGMA
September 2025
Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany.
Introduction: This study explores high-impedance surface (HIS) metamaterial shields for enhancing the transmit field in whole-body MRI at 7 T. We studied the possibility of placing a metamaterial layer between the gradient coil and bore liner using electromagnetic simulations to evaluate B and SAR efficiency across different impedances.
Materials And Methods: Simulations were performed in three stages, first metamaterial design and characterization, then single-element dipole simulations with a homogenous phantom, and finally, simulations including a four-element arrays with a virtual body model, including the whole scanner geometry.
Food Chem
September 2025
Institute of Quality Standard and Testing Technology for Agro-products, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
Fluoroquinolones are a popular class of antibiotics, which can lead to residues in food and the environment due to their abuse and illegal use. Consequently, this can pose a threat to human health. We hypothesized that a core-shell structured magnetic lanthanide metal-organic framework could serve as an effective dual-mode nanosensor, leveraging its antenna effect and peroxidase (POD)-like activity for the sensitive detection of fluoroquinolones.
View Article and Find Full Text PDFACS Nano
September 2025
School of Physics and Key Lab of Quantum Materials and Devices of the Ministry of Education, Southeast University, Nanjing 211189, P. R. China.
While hexagonal boron nitride (hBN) hosts promising room-temperature quantum emitters for hybrid quantum photonic circuits, scalable deterministic integration and insufficient brightness alongside low photon collection and coupling efficiencies remain unresolved challenges. We present a femtosecond laser nanoengineering platform that enables the site-specific generation of hBN single-photon source (SPS) arrays. First-principles density functional theory (DFT) calculations and polarization-resolved spectroscopy confirm the atomic origin of emission as interfacial defects at hBN/SiO heterojunctions.
View Article and Find Full Text PDFSci Adv
September 2025
State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Science, Beijing 100101, China.
Insects, unlike vertebrates, use heteromeric complexes of odorant receptors and co-receptors for olfactory signal transduction. However, the secondary messengers involved in this process are largely unknown. Here, we use the olfactory signal transduction of the aggregation pheromone 4-vinylanisole (4VA) as a model to address this question.
View Article and Find Full Text PDFPhys Rev Lett
August 2025
University of Sheffield, School of Mathematics and Statistics, Hounsfield Road, Sheffield S3 7RH, United Kingdom.
In a broad class of cosmological models where spacetime is described by a pseudo-Riemannian manifold, photons propagate along null geodesics, and their number is conserved, upcoming gravitational wave (GW) observations can be combined with measurements of the baryon acoustic oscillation (BAO) angular scale to provide model-independent estimates of the sound horizon at the baryon drag epoch. By focusing on the accuracy expected from forthcoming surveys such as the Laser Interferometer Space Antenna GW standard sirens and dark energy spectroscopic instrument (DESI) or Euclid angular BAO measurements, we forecast a relative precision of σ_{r_{d}}/r_{d}∼1.5% within the redshift range z≲1.
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