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Physically consistent gravitational waveform for capturing beyond general relativity effects in the compact object merger phase

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Physical Review D 2024年第8期109卷 084058-084058页

作者： Daiki Watarai Atsushi Nishizawa Kipp Cannon Graduate School of Science The University of Tokyo Tokyo 113-0033 Japan Research Center for the Early Universe (RESCEU) Graduate School of Science The University of Tokyo Tokyo 113-0033 Japan Physics Program Graduate School of Advanced Science and Engineering Hiroshima University Higashi-Hiroshima Hiroshima 739-8526 Japan

The merger phase of compact binary coalescences is the strongest gravity regime that can be observed. To test the validity of general relativity (GR) in strong gravitational fields, we propose a gravitational waveform parametrized for deviations from GR in the dynamical and nonlinear regime of gravity. Our fundamental idea is that perturbative modifications to a GR waveform can capture possible deviations in the merger phase that are difficult to model in a specific theory of gravity. One of notable points is that our waveform is physically consistent in the sense that the additional radiative losses of energy and angular momentum associated with beyond-GR modifications are included. Our prescription to ensure physical consistency in the whole coalescence process is expected to be applicable to any deviation from the standard model of compact binary coalescence, such as the extended models of gravity or the environmental effects of compact objects, as long as perturbative modifications are considered. Based on the Fisher analysis and the compatibility with Einstein-dilaton Gauss-Bonnet waveforms, we show that our parametrization is a physically consistent minimal one that captures the deviations in the nonlinear regime.

关键词： Gravitational waves

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Multiband Patch Antenna Design Using Nature-Inspired Optimization Method

IEEE Open Journal of Antennas and Propagation

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IEEE Open Journal of Antennas and Propagation 2021年 2卷 151-162页

作者： Boursianis, Achilles D. Papadopoulou, Maria S. Pierezan, Juliano Mariani, Viviana C. Coelho, Leandro S. Sarigiannidis, Panagiotis Koulouridis, Stavros Goudos, Sotirios K. ELEDIA@AUTH Research Group School of Physics Aristotle University of Thessaloniki Thessaloniki54124 Greece Department of Electrical Engineering Federal University of Parana Curitiba80060-000 Brazil Industrial and Systems Engineering Graduate Program and Mechanical Engineering Graduate Program Pontifical Catholic University of Parana Curitiba80215-901 Brazil Department of Electrical and Computer Engineering University of Western Macedonia Kozani501 00 Greece Electrical and Computer Engineering Department University of Patras Patras26504 Greece

Radio frequency energy harvesting has attracted considerable interest as a technique of enabling self-powered wireless networks. This technique faces several challenges, such as the receiving and the rectifying modules of a rectenna system. Multiband antennas provide several comparative advantages against the goal of maximizing the amount of energy harvesting. In this work, we present a multiband microstrip patch antenna with three slits operating in the LoRaWAN (Long Range Wide Area Network) and the cellular (GSM-1800 and UMTS) communication frequency bands. A feasible solution of the antenna is obtained by the application of a recently introduced nature-inspired optimization technique, namely the Coyote Optimization Algorithm. The proposed antenna operates satisfactorily in the LoRaWAN (Long Range Wide Area Network) and the cellular (GSM-1800 and UMTS) communication frequency bands. Measured results of the proposed antenna exhibit an acceptable performance (multiband frequency operation, maximum gain of 3.94 dBi, broadside operation) and demonstrate features of operation, which make it a strong candidate for various RF energy harvesting applications. © 2020 IEEE.

关键词： Microstrip antennas

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Anomalous properties of spark plasma sintered boron nitride solids

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Materials Today 2025年 86卷 42-51页

作者： Biswas, Abhijit Serles, Peter Alvarez, Gustavo A. Schimpf, Jesse Hache, Michel Kong, Jonathan Demingos, Pedro Guerra Yuan, Bo Pieshkov, Tymofii S. Li, Chenxi Puthirath, Anand B. Gao, Bin Gray, Tia Zhang, Xiang Murukeshan, Jishnu Vajtai, Robert Dai, Pengcheng Singh, Chandra Veer Howe, Jane Zou, Yu Martin, Lane W. Clancy, James Patrick Tian, Zhiting Filleter, Tobin Ajayan, Pulickel M. Department of Materials Science and Nanoengineering Rice University HoustonTX77005 United States Department of Mechanical & Industrial Engineering University of Toronto 5 King's College Road TorontoM5S 3G8 Canada Sibley School of Mechanical and Aerospace Engineering Cornell University IthacaNY14853 United States Department of Materials Science and Engineering University of California Berkeley94720 United States Department of Materials Science and Engineering University of Toronto 184 College St TorontoM5S 3E4 Canada Department of Physics and Astronomy McMaster University HamiltonL8S 4M1 Canada Applied Physics Graduate Program Smalley-Curl Institute Rice University HoustonTX77005 United States Department of Physics and Astronomy Rice University HoustonTX77005 United States Materials Sciences Division Lawrence Berkeley National Laboratory Berkeley94720 United States

Hexagonal boron nitride (h-BN) is a brittle ceramic with a layered structure, however, recent experiments have suggested that inter-layer structural engineering could be key to new structural and functional properties. Here we report the scalable bulk synthesis of high-density crystalline h-BN solids, by using high-temperature spark plasma sintering (SPS) of h-BN powders, which show high values of mechanical strength, ductility, dielectric constant, thermal conductivity, and exceptional neutron radiation shielding capability. Through exhaustive characterizations we reveal that SPS induces non-basal plane crystallinity, twisting of layers, and facilitates inter-grain fusion with a high degree of in-plane alignment across macroscale dimensions, resulting in near-theoretical density and improved properties. Our findings highlight the importance of material design, via new approaches such as layer twisting and interlayer interconnections, to create novel ceramics with properties that could go beyond their intrinsic limits. © 2025

关键词： Ductility

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The abundance and localization of environmental microplastics in gastrointestinal tract and muscle of Atlantic killifish (Fundulus heteroclitus): a pilot study

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Microplastics and Nanoplastics 2024年第1期4卷 23页

作者： Pitt, Jordan A. Gallager, Scott M. Youngs, Sarah Michel, Anna P. M. Hahn, Mark E. Aluru, Neelakanteswar Biology Department Woods Hole Oceanographic Institution Woods Hole 02543 MA United States Massachusetts Institute of Technology (MIT) – Woods Hole Oceanographic Institution (WHOI) Joint Graduate Program in Oceanography and Oceanographic Engineering Woods Hole 02543 MA United States CoastalOceanVision Inc 10 Edgerton Drive North Falmouth 02556 MA United States Department of Applied Ocean Physics and Engineering Woods Hole Oceanographic Institution Woods Hole 02543 MA United States

Microplastics (MPs) have been found in a diverse range of organisms across trophic levels. While a majority of the information on organismal exposure to plastics in the environment comes from gastrointestinal (GI) data, the prevalence of MP particles in other tissues is not well understood. Additionally, many studies have not been able to detect the smallest, most prevalent, MPs (1 µm – 5 mm) that are the most likely to distribute to tissues in the body. To address these knowledge gaps, MPs in the GI tract and muscle of Atlantic killifish (Fundulus heteroclitus) collected from two sites (Falmouth and Bourne) on Buzzards Bay, Cape Cod, MA were quantified down to 2 µm in size. Eight fish from Falmouth and 10 fish Bourne site were analyzed. Fourier-transform infrared spectroscopy and Raman spectroscopy were used to identify all particles. The mean concentrations of MPs in the GI tract and muscle from fish collected from Falmouth was 85.5 ± 70.2 and 11 ± 12.5 particles per gram wet weight, respectively. Fish collected from Bourne site had mean particle concentrations of 12.2 ± 18.1 and 1.69 ± 5.36 particles per gram wet weight. Of the 2,008 particles analyzed in various fish tissue samples, only 3.4% (69 particles) were identified as plastic;polymers included nylon, polyethylene, polypropylene, and polyurethane. MPs detected in the GI tract samples also tended to be more diverse in both size and polymer type than those found in the muscle. We found that MPs < 50 µm, which are often not analyzed in the literature, were the most common in both the GI tract and muscle samples. There was not a significant correlation between the MP content in the muscle compared to the GI tract, indicating that GI tract MP abundance cannot be used to predict non-GI tract tissue MP content;however, MP abundance in muscle correlated with fish total length, suggesting potential bioaccumulation of these small MPs. © The Author(s) 2024.

关键词： Bioaccumulation Fish Fourier-transform infrared spectroscopy Microplastics Raman spectroscopy Translocation

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Quantum Wrapper Networking: Investigating the Noise Impact of Classical Headers on the Quantum Payload

Quantum Wrapper Networking: Investigating the Noise Impact o...

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2024 Frontiers in Optics, FiO 2024

作者： Gül, Gamze On, Mehmet Berkay Tan, Shannon G. Proietti, Roberto Kanter, Gregory S. Yoo, S.J. Ben Kumar, Prem Graduate Program in Applied Physics Northwestern University 2145 Sheridan Road EvanstonIL60208 United States Department of Electrical and Computer Engineering University of California Davis DavisCA95616 United States Center for Photonic Communication and Computing Dept. of Electrical and Computer Eng. Northwestern University EvanstonIL60208 United States Department of Electronics and Telecommunications Engineering Politecnico di Torino Italy

We study the impact in time and frequency domains of classical headers on quantum payloads in quantum wrapper networking. We identify and characterize in-fiber scattering processes that produce noise photons degrading...

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Simulation of Cable-Driven Parallel Robot (CDPR) for Application in Creating Batik Patterns

Simulation of Cable-Driven Parallel Robot (CDPR) for Applica...

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International Conference on Instrumentation Control and Automation (ICA)

作者： Indah Radityo Putri Alfisena Juwandana Eko Mursito Budi Estiyanti Ekawati Komarudin Kudiya Instrumentation and Control Graduate Program Institut Teknologi Bandung Bandung Indonesia Departement of Engineering Physics Engineering Physics Research Group Institut Teknologi Bandung Bandung Indonesia Rumah Batik Komar Bandung Indonesia

The usage of the cable-driven parallel robot (CDPR) is proposed to create a batik pattern. In the proposed CDPR system, the artist can intervene in the pattern-making process to maintain pattern uniqueness. Therefore, to provide the system's flexibility and simplicity, CDPR with four cables will be used where all the cables only connect to the top of the end-effector. The design of four cables with four poles will give a simple structure, and the pole can be moved easily according to the cloth's size, usually in the shape of a rectangle. This flexible design allows the artist to intervene via software or manually push the end effector. In this paper, we explored the cable's length calculation, various path simulations to see system accuracy and flexibility, and the analysis of the CDPR workspace. From the CDPR simulation, we can conclude that the longest cable length needed is 1.22 meters, and the shortest is 0 due to the assumption of the pulley as a point. Implementing inverse kinematics in simulation shows that the end-effector can follow various paths, including straight line, square, circle, diagonal, two-circular, spiral, and planetary orbit. We also calculate the percentage of the area if the pulley has a minimal degree to the pole. With the assumption that the minimal degree is 5°, the %Area we got is 75.6%.

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Design and Implementation of Four Cables Suspended Cable-driven Parallel Robot for Pendulum Batik Machine

Design and Implementation of Four Cables Suspended Cable-dri...

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International Conference on Advanced Mechatronics, Intelligent Manufacture, and Industrial Automation (ICAMIMIA)

作者： Alfisena Juwandana Estiyanti Ekawati Eko Mursito Budi Indah Radityo Putri Komarudin Kudiya Instrumentation and Control Graduate Program Institut Teknologi Bandung Bandung Indonesia Departement of Engineering Physics Engineering Physics Research Group Institut Teknologi Bandung Bandung Indonesia Rumah Batik Komar Bandung Indonesia

This study researches the fusion of Indonesian traditional batik art with modernity called the Batik Pendulum. A machine based on Cable-Driven Parallel Robot (CDPR) architecture has been developed to automate the process of Batik Pendulum drawing. The suspended CDPR design uses four cables to provide flexibility and space efficiency. An artist may draw rough pendulum patterns utilizing a tablet as a human interface, which are then coded into coordinate-based code and sent to a microcontroller. The microcontroller drives four stepper motors to synchronize the length of the cables. Therefore, the platform carrying the wax can be moved to create the desired batik patterns. The machine was tested by dripping the paint on the fabric along the test path to validate the accuracy of the patterns. The Mean Absolute Percentage Error test results for the x, y, and radius axes were 1.63%, 1.95%, and 6.33%, while the maximum error values in the movement of the x, y, and radius axes were 8.64, 18.3, and 24.08 mm. This research represents a significant step in preserving Indonesia's cultural heritage while embracing contemporary creativity.

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Sodium niobate with high photocatalytic activity for the removal of organic dye and inactivation of Escherichia coli, Staphylococcus aureus, and Klebsiella pneumoniae bacteria: the effect of Zn doping on these properties

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Ceramics International 2025年

作者： Fernandes, Daiane Raubach, Cristiane Trassante, Carla Dias, Vagner Melo, Luize Silveira, Marcelle Carvalho, Ramon Moreira, Mario Jardim, Pedro Ferrer, Mateus Giongo, Janice Vaucher, Rodrigo Longo, Elson Cava, Sergio Post-Graduate Program in Materials Science and Engineering Federal University of Pelotas RS Pelotas96010-610 Brazil Post-Graduate Program in Microbiology and Parasitology Federal University of Pelotas RS Capão do Leão96160-000 Brazil Post-Graduate Program in Physics Federal University of Pelotas RS Capão do Leão96160-000 Brazil Functional Materials Development Center São Carlos Federal University SP São Carlos13565-905 Brazil

NaNbO3 doped with Zn (0.00, 0.02, and 0.05 mmol) was synthesized by the microwave-assisted hydrothermal method. Photocatalytic and antibacterial activities were investigated. X-ray diffraction revealed the coexistence of two orthorhombic symmetries (P21ma and Pbma), with doping promoting a progressive increase in the Pbma fraction. All samples exhibited a fiber-like shape (diameter of ∼200 nm), which remained unchanged with doping. The low Zn content (0.02 mmol) reduced the band gap energy from 3.08 to 2.95 eV. As a result, this sample exhibited superior photocatalytic activity, achieving 100 % RhB dye degradation within 45 min, under UV light. Scavenger tests revealed that hydroxyl radicals, holes, and superoxide radical anions were the main active species involved in the photocatalytic reaction. Additionally, the photocatalyst demonstrated excellent recyclability over three consecutive cycles. Pure NaNbO3 exhibited strong antibacterial activity, completely inhibiting the growth of S. aureus, E. coli, and K. pneumoniae at the tested concentrations. Although the Zn-doped sample also demonstrated antibacterial action, the response was concentration-dependent. This study is the first report on Zn doping in NaNbO3, as well as the first investigation of its antibacterial activity against K. pneumoniae and S. aureus. © 2025 Elsevier Ltd and Techna Group S.r.l.

关键词： Escherichia coli

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Steady-state phases and interaction-induced depletion in a driven-dissipative chirally-coupled dissimilar atomic array

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Physical Review Research 2024年第2期6卷 023232-023232页

作者： Shao-Hong Chung I Gusti Ngurah Yudi Handayana Yi-Lin Tsao Chun-Chi Wu G.-D. Lin H. H. Jen Department of Physics and Center for Quantum Science and Engineering Taipei 10617 Taiwan Molecular Science and Technology Program Taiwan International Graduate Program Department of Physics Physics Division National Center for Theoretical Sciences Taipei 10617 Taiwan Trapped-Ion Quantum Computing Laboratory Hon Hai Research Institute Taipei 11492 Taiwan

A nanophotonic waveguide coupled with an atomic array forms one of the strongly coupled quantum interfaces to showcase many fascinating collective features of quantum dynamics. In particular, for a dissimilar array of two different interparticle spacings with competing photon-mediated dipole-dipole interactions and directionality of couplings, we study the steady-state phases of atomic excitations under a weakly driven condition of laser field. We identify a partial set of steady-state phases of the driven system composed of combinations of steady-state solutions in a homogeneous array. We also reveal the intricate role of the atom at the interface of the dissimilar array in determining the steady-state phases and find an alteration in the dichotomy of the phases strongly associated with steady-state distributions with crystalline orders. We further investigate in detail the interaction-induced depletion in half of the dissimilar array, where the blockaded region results from two contrasting interparticle spacings near the reciprocal coupling regime. This can be further evidenced from the analytical solutions under the reciprocal coupling. Our results can provide insights in the driven-dissipative quantum phases of atomic excitations with nonreciprocal couplings and pave the avenues toward quantum simulations of exotic many-body states essential for quantum information applications.

关键词： Collective behavior Dissipative dynamics Nanophotonics Phase diagrams Dipole approximation Two-level models

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Unravelling the strong interplay for interfacial magnetic switching in metal-organic-based spintronics

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Journal of Materials Chemistry C 2024年第11期12卷 3931-3942页

作者： Chen, Wan-Ting Yu, Li-Chung Lin, Jiu-Hua Cheng, Su Ling Shiu, Hung Wei Lai, Yu-Ling Chu, Ying-Hao Chin, Yi-Ying Wang, Jeng-Han Hsu, Yao-Jane National Synchrotron Radiation Research Center Hsinchu30076 Taiwan Graduate Program for Science and Technology of Accelerator Light Sources National Yang Ming Chiao Tung University Hsinchu30076 Taiwan Department of Materials Science and Engineering National Tsing Hua University Hsinchu30013 Taiwan Department of Chemistry National Taiwan Normal University Taipei11677 Taiwan Department of Photonics National Cheng Kung University Tainan70101 Taiwan Department of Physics National Chung Cheng University Chiayi62102 Taiwan

Organic semiconductors are promising building blocks for multifunctional spintronics. The spinterface plays a key role in affecting the magnetic properties of the performance of spin-based devices. Herein, we reveal the strong interfacial interplay affecting the magnetic switching at the interface of the synthetic paramagnetic tris(8-hydroxyquinoline)iron(iii) (Feq3) layer on the ferromagnetic surface. In combination with synchrotron-based analysis and density functional theory (DFT) calculations, we observed that the robust magnetic interactions of the Co/Feq3 system were strongly influenced by the interfacial reaction between Co and Feq3. As the charge transferred from the contacted Co to Feq3, the central iron was reduced from Fe(iii) to Fe(ii) and hybridized with the 8-hydroxyquinoline, causing spin polarization at the interface. The reduced central Fe(ii) exhibited apparent ferromagnetic ordering after contact with the ferromagnetic Co substrate. With increasing the Feq3 layer thickness, the central Fe reverted to its original Fe(iii) state, resulting in the disappearance of ferromagnetic ordering. The thickness dependence of the Feq3 layer on the magnetic response could be used to tune the spinterface properties and thus the interfacial magnetic interplay. These findings reveal the effect of the strong interfacial redox on the spinterface and open up a promising approach for the use of metal-organic materials in oragnic spintronic devices. © 2024 The Royal Society of Chemistry.

关键词： Organometallics

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