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Light People:Professor Che Ting Chan,curiosity drives to create the impossibilities

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Light(Science & Applications) 2024年第7期13卷 1229-1233页

作者： Tingting sun Ying Xiong Light Publishing Group Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesNo.3888 Dong Nanhu RoadChangchun 130033China College of Intelligence Science and Technology National University of Defense TechnologyNo.109 Deya RoadChangsha 410073China

editorial“When something is said to be impossible,there are two points for researchers to initially clarify:whether it really is forbidden by the laws of nature;or whether it is simply that no material that currently exists in nature can do that.”Metamaterials are such magical beings,which have physical properties like invisibility,negative refraction,super-resolution,and perfect absorption that are absent from natural *** has been rated by Science as one of the top ten scientific and technological breakthroughs affecting human beings in the 21st *** this issue of Light People,we spoke with a“magic”creator,Professor Che Ting Chan,the Associate VicePresident(Research&Development)of the Hong Kong University of Science and Technology(HKUST),Member of the Hong Kong Academy of Sciences and Fellow of the American Physical *** has researched a number of theoretical problems in material physics,investigated the theory behind what they seek to achieve,and modulated light(electromagnetism)and acoustic waves through *** the following,let’s take a closer look at Professor Che Ting Chan’s research life,and appreciate his style and the background of his accomplishment.

关键词： breakthrough closer visibility

Molecular Chaperone-Dependent Polymer Translocation through nanopores: The effects of Chaperone Concentration and Chaperone-Polymer Interaction

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Chinese Journal of Polymer Science 2024年第1期42卷 125-132,I0011页

作者： Chang-Sheng Zuo Kang Wang Li-Zhen sun Ting-Ting sun Department of Physics Zhejiang University of Science and TechnologyHangzhou 310023China Department of Applied Physics Zhejiang University of TechnologyHangzhou 310014China

The polymer translocation through a nanopore from a donor space(or named cis side) to a receiver space(trans side) in the chaperone-induced crowded environment has attracted increasing attention in recent years due to its significance in biological systems and technological applications. In this work, we mainly focus on the effects of chaperone concentration and chaperone-polymer interaction on the polymer translocation. By assuming the polymer translocation to be a quasi-equilibrium process, the free energy F of the polymer can be estimated by Rosenbluth-Rosenbluth method and then the translocation time τ can be calculated by Fokker-Plank equation based on the obtained free energy landscape. Our calculation results show that the translocation time can be controlled by independently tuning the chaperone concentration and chaperone-polymer interaction at the cis side or the trans side. There exists a critical chaperone-polymer attraction ε~*=-0.2 at which the volume exclusion and interaction effects of the chaperone can balance each other. Additionally, we also find that at large chaperone-polymer attraction, the translocation time is mainly governed by the diffusion coefficient of the polymer.

关键词： Polymer translocation Rosenbluth-Rosenbluth method Fokker-Plank equation Free energy landscapes

Robust hybrid bismuth perovskites as potential photocatalysts for overall water splitting

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nano Research 2024年第5期17卷 4593-4601页

作者： Antonio J.Chacón-García Herme G.Baldovi Artem A.Babaryk Antonio Rodríguez-Diéguez Sergio navalón Yolanda Pérez Hermenegildo García Patricia Horcajada Advanced Porous Materials Unit IMDEA Energy InstituteAvda.Ramón y Cajal 328935 MóstolesMadridSpain Departamento de Química Universitat Politècnica de València46022 ValènciaSpain Departamento Química Inorgánica Universidad de Granada1807GranadaSpain Departamento de Biología y Geología Física y Química Inorgánica.ESCET.Universidad Rey Juan Carlos28933 MóstolesMadridSpain Instituto de tecnología química CSIC-UPV Universitat Politècnica de València(UPV)46022Spain

Organic-inorganic hybrid perovskites have gained great attention as promising photocatalysts for hydrogen ***,due to their poor stability in water,the use of aqueous hydrohalic acid solutions is specifically required for an efficient hydrogen ***,three novel photoactive lead-free hybrid perovskites based on bismuth and triazolium cations(denoted as IeF-15,IeF-16,and IeF-17(IeF stands for IMDeA energy frameworks))were synthesized and fully characterized(structural,compositional,optical,etc.).Further,these solids were proposed as photocatalysts for the challenging gas phase overall water splitting(OWS)***,IeF-16 thin films exhibited a remarkable photocatalytic activity in both H_(2) and O_(2) evolution,as a consequence of its appropriate bandgap and energy-band alignment,achieving hydrogen evolution rates ofμmol·g_(H_(2))^(-)1846 and 360 after 24 h under ultraviolet-visible(UV-vis)irradiation or simulated solar irradiation,*** study additionally highlights the remarkable structural and photochemical stability of IeF-16 under different operational conditions(*** volume,irradiation and temperature),paving the way for green hydrogen production from OWS using perovskite-based photocatalysts.

关键词： bismuth-based hybrid perovskites thin films photocatalysis overall water splitting green hydrogen

Thermal analysis of the Rindler-Schwarzschild black hole via corrected entropy

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Communications in Theoretical Physics 2024年第9期76卷 95-106页

作者： Allah Ditta Xia Tiecheng Riasat Ali AliÖvgün Department of Mathematics Shanghai University and Newtouch Center for Mathematics of Shanghai UniversityShanghai200444China Physics Department Eastern Mediterranean UniversityFamagusta99628 North Cyprus via Mersin 10Turkiye

In this study,we investigate the thermodynamic characteristics of the Rindler–Schwarzschild black hole *** analysis encompasses the examination of energy emission,Gibbs free energy,and thermal *** calculate various quantities such as the Hawking temperature,geometric mass,and heat capacity to assess the local and global thermodynamic *** temperature of the black hole is determined using the first law of thermodynamics,while the energy emission rate is evaluated as *** computing the Gibbs free energy,we explore the phase transition behavior exhibited by Rindler–Schwarzschild black hole,specifically examining the swallowing ***,we derive the corrected entropy to investigate the influence of thermal fluctuations on small and large black ***,we compare the impact of correction terms on the thermodynamic system by comparing the results obtained for large black holes and small black holes.

关键词： black holes thermodynamics thermal fluctuations heat capacity Gibbs free energy energy emission Rindler–Schwarzschild black hole

Catalyst design and structure control for photocatalytic refineries of cellulosic biomass to fuels and chemicals

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Journal of energy Chemistry 2024年第7期94卷 102-127页

作者： Lulu sun nengchao Luo State Key Laboratory of Catalysis Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

Lignocellulosic biomass is the largest renewable hydrocarbon resource on *** cellulose,one of the major components of lignocellulose,powered by solar energy is a promising way of providing lowcarbon-footprint energy chemicals such as H_(2),HCOOH,CO,and transportation ***-of-the-art biorefineries target the full use of biomass feedstocks as they have a maximum collection radius of 75-100 km,requesting efficient and selective photocatalysts that significantly influence the outcome of photocatalytic ***-performed photocatalysts can harvest a broad solar spectrum and are active in breaking the chemical bonds of cellulose,decreasing the capital investments of ***,photocatalysts should control the selectivity of cellulose conversion,originating target products to level down separation *** separation in photocatalysts and interfacial charge transfer between photocatalysts and cellulose affect the activity and selectivity of cellulose refineries to H2 and carbonaceous *** account for the challenges above,this review summarizes photocatalysts for the refineries of cellulose and downstream platform molecules based on the types of products,with the structure features of different types of photocatalysts discussed in relation to the targets of either improving the activity or product *** addition,this review also sheds light on the methods for designing and regulating photocatalyst structures to facilitate photocatalytic refineries of cellulose and platform molecules,meanwhile summarizing proposed future research challenges and opportunities for designing efficient photocatalysts.

关键词： Photocatalysts Biorefineries Cellulose Fuels Hydrogen

Blindness-free beam scanning antenna with array of array architecture: principle,design,and experiment

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Science China(Information Sciences) 2024年第3期67卷 209-224页

作者： Jianxu sun Yujian CHenG School of electronic Science and engineering University of electronic Science and Technology of China

This paper presents a 66–76-GHz sparsely-excited phased array antenna with the array of array(Ao A) architecture for eliminating the blindness and suppressing the grating lobe when scanning. For the array antennas printed on the thick dielectric layers with high relative permittivity, scanning blindness appears and seriously impacts the radiation performance. To address this issue, the Ao A topology is developed first. It finds that the scanning blindness appears due to the coupling of the radiating Floquet modes to the non-radiating surface wave(SW) modes. Therefore, the array is divided into two types of domino *** inner-phase distributions are introduced into the domino subarrays to break the one-to-one relationship between the Floquet mode and the SW mode. Then, the blindness inside ±60° scanning volume is eliminated by the aperiodic subarrays. Meanwhile, the aperiodic inner-phase distributions enhance the aperiodicity of the array and contribute to suppressing the grating lobe when scanning. next, the meta-surface-based dipole with the shorted post is chosen as the unit cell for the proposed aperiodic array. Based on these methods,the array achieves the wide-scanning performance of ±60° in the e-plane and ±30° in the H-plane, without the blindness and the grating lobe. Finally, the 16×16 array is built and simulated with the dimension of32 mm × 32 mm. At the highest operating frequency, the simulated gains are 28.42, 25.17, and 24.01 d Bi when scanning to the broadside, 50° in the e-plane, and 30° in the H-plane, respectively. Compared to the ideal gain, it shows that the simulated radiation efficiency is about 84.13%, 62.08%, and 35.23% when scanning to the broadside, 50° in the e-plane, and 30° in the H-plane, respectively. The worst transmission coefficient, i.e., the worst isolation, is-11.97 d B between the central element and its two adjacent elements in the e-plane. The array prototypes are fabricated, and the experiments are carried out to ver

关键词： 6G communication systems phased array AoA aperiodic subarray wideband wide-scanning surface-wave scanning blindness grating lobe

Self-Aligning Multi-Modal Transformer for Oropharyngeal Swab Point Localization

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Tsinghua Science and Technology 2024年第4期29卷 1082-1091页

作者： Tianyu Liu Fuchun sun Department of Computer Science and Technology Tsinghua UniversityBeijing 100083China

The oropharyngeal swabbing is a pre-diagnostic procedure used to test various respiratory diseases, including COVID and Influenza A (H1n1). To improve the testing efficiency of testing, a real-time, accurate, and robust sampling point localization algorithm is needed for robots. However, current solutions rely heavily on visual input, which is not reliable enough for large-scale deployment. The transformer has significantly improved the performance of image-related tasks and challenged the dominance of traditional convolutional neural networks (Cnns) in the image field. Inspired by its success, we propose a novel self-aligning multi-modal transformer (SAMMT) to dynamically attend to different parts of unaligned feature maps, preventing information loss caused by perspective disparity and simplifying overall implementation. Unlike preexisting multi-modal transformers, our attention mechanism works in image space instead of embedding space, rendering the need for the sensor registration process obsolete. To facilitate the multi-modal task, we collected and annotate an oropharynx localization/segmentation dataset by trained medical personnel. This dataset is open-sourced and can be used for future multi-modal research. Our experiments show that our model improves the performance of the localization task by 4.2% compared to the pure visual model, and reduces the pixel-wise error rate of the segmentation task by 16.7% compared to the Cnn baseline.

关键词： segmentation localization transformer multi-modal perception robotic perception

enhanced heavy and extra heavy oil recovery: Current status and new trends

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PeTROLeUM 2024年第3期10卷 399-410页

作者： Gomaa, Sayed Salem, Khalaf G. el-hoshoudy, A. n. Al Azhar Univ Fac Engn Min & Petr Engn Dept Cairo Egypt South Valley egyptian Petr Holding Co GAnOPe Dept Reservoir Engn Cairo Egypt egyptian Petr Res Inst PVT Lab Prod Dept Cairo 11727 Egypt egyptian Petr Res Inst ePRI PVT Serv Ctr Cairo 11727 Egypt

Due to the increased demand for energy resources these days, especially due to the Russian-Ukrainian war, the focus of the major countries is turning strongly towards improving oil production, especially heavy and extra heavy oil, which represents 40% of the world oil reserve. Steam-based and thermal (eOR) procedures are promising techniques for recovering heavy oil reservoirs, but they suffer from a sequence of problems and complications that arise after long-term application. These complications comprise steam breakthrough, steam overlap, and steam/rock interactions. This research presents the currently applied techniques to maximize the productivity of heavy oil, such as steam injection, cyclic steam stimulation, in-situ combustion, and steam-assisted gravity drainage. Thermal technologies face numerous obstacles, as they are energy and water-intensive processes that are not environmentally friendly. The research also presents future trends in energy-saving and environmentally friendly techniques that enhance heavy oil recovery through vapor extraction (VAPeX) steam-solvent hybrid techniques, electromagnetic energy, sonication, and nanotechnology. The findings of this review reported that all the presented techniques focus on how to reduce the oil viscosity and in-situ upgrade the crude oil properties. In turn, these enhance both the productivity rate and oil recovery and minimize the production cost. This article can be considered a comprehensive review of thermal recovery methods in heavy and extra-heavy oil, in addition to screening criteria used for each method. (c) 2023 Southwest Petroleum University. Publishing services by elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-nC-nD license (http:// ***/licenses/by-nc-nd/4.0/).

关键词： enhanced oil recovery Heavy crude oil Steam flood Hybrid techniques nanotechnology In-SITU-COMBUSTIOn ASSISTeD GRAVITY-DRAInAGe CYCLIC-STeAM-STIMULATIOn ROCK WeTTABILITY VAPOR eXTRACTIOn InJeCTIOn PeRFORMAnCe BITUMen SAGD eOR

Tuning structural,electrical,dielectric and magnetic properties of Mg-Cu-Co ferrites via dysprosium(Dy^(3+))doping

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Journal of Rare earths 2024年第1期42卷 137-146,I0005页

作者： Maria Akhtar M.S.Hasan nasir Amin n.A.Morley Muhammad Imran Arshad Department of Physics Government College UniversityFaisalabad38000Pakistan Department of Physics The University of Lahore53700Pakistan Department of Materials Science and engineering The University of SheffieldS13JDUK Department of Physics&Astronomy University College LondonUK

In current research work,Dy3+substituted Mg0.5Cu0.25Co0.25Fe2-xDyxO4(0.0≤x≤0.04 with the step interval of 0.01)soft ferrites were synthesized by the sol-gel auto combustion *** prepared samples were characterized by the techniques using X-ray diffraction(XRD),scanning electron microscopy(SeM),energy dispersive X-ray spectroscopy(eDS),Fourier transform infrared(FTIR)spectroscopy,curre nt-voltage(Ⅰ-Ⅴ)measurement,LCR meter,vibrating sample magnetometer(VSM)and *** data reveal that the average crystallite size is 49.71 nm and the lattice constant is 0.83703 nm for sample x=*** non-uniform grain growth was demonstrated by micrographs and impurity-free elemental composition was observed from eDX *** DC resistivity has an increasing and decreasing trend in ferromagnetic and paramagnetic regions with an increase in ***,the high resistivity is observed with the order of 1010Ω·cm,and the activation energy is 0.944 eV for samples x=*** dielectric parameters including dielectric constant,dielectric losses,and impedance gradually decrease with the increase in frequency from 8 Hz to 8 *** minimum dielectric loss at high frequency is found for sample x=*** coercivity(Hc)and saturation magnetization(Ms)are found in the ranges of 520.82-544.02 Oe and 20.5841-21.1473 emu/g,*** observations confirm that dysprosium(x=0.03)doped MCC-soft ferrites may be applicable in transformer cores,microwave absorbance,and telecommunication devices.

关键词： Soft ferrites DC resistivity Dielectric loss Impedance Coercivity Rare earths