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Interplay between Microscopic Structures and Macroscopic Viscoelastic Properties of Polyampholyte Gels

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Chinese Journal of Polymer Science 2024年第9期42卷 1360-1367,I0008页

作者： you-Cai Xue yi-Ming Yang Di Jia Beijing National Laboratory for Molecular Sciences Laboratory of Polymer Physics and ChemistryInstitute of ChemistryChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China

Polyampholyte gels,which have hierarchical structures,exhibit excellent self-healing properties and have great promise for biomaterials and *** investigated the relationship between microscopic structures and macroscopic viscoelastic properties of polyampholyte gels and found three factors influencing their viscoelastic properties,including the chemical crosslinking bonds,topological entanglements controlled by monomer concentration,and the ionic *** strength plays a major role on the strength of ionic bonds.A crossover point of elastic modulus and loss modulus was observed in the dynamic frequency sweeps at low monomer concentration or low chemical crosslinking density for gels with intermediate strength of ionic *** solid-liquid transition signaled by the crossover point is a typical feature of dynamic associated gels,representing the dynamical association-dissociation of the ionic bonds and full relaxation of the topological entanglements in the gel *** the crossover point disappears when the ionic bonds are too weak or too strong to form“permanent”***,in the non-linear yielding measurement,gels with intermediate strength of the ionic bonds are ductile and yield at very large shear strain due to the self-healing properties and the dynamic association-dissociation of the ionic *** the self-healing properties disappear when the ionic bond strength is too weak or too *** work reveals the mechanism of how the dynamic association-dissociation of ionic bonds influences both the linear and non-linear viscoelastic properties of the polyampholyte gels.

关键词： Polyampholyte gel Ionic bond Topological entanglement Self-healing Hierarchical structure

Chiral thermally activated delayed fluorescence materials for circularly polarized organic light-emitting diodes

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Science China Chemistry 2024年第4期67卷 1097-1116页

作者： Li Yuan yi-Pin Zhang you-Xuan Zheng State Key Laboratory of Coordination Chemistry Collaborative Innovation Center of Advanced MicrostructuresJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Chirality is an important natural characteristic of organic molecules,and chiral organic molecules have shown extensive application in areas such as pharmaceutical development and material *** from the ability to achieve circularly polarized luminescence(CPL),chiral luminescent materials have shown potential applications in anti-glare display,optical communication and,3D display,*** to the ability to harvest both singlet and triplet excitons by a fast reverse intersystem crossing process without involving noble metals,chiral thermally activated delayed fluorescence(TADF)materials with point chirality,axial chirality,planar chirality and helical chirality are regarded as the state-of-the-art materials for circularly polarized organic light-emitting diodes(CP-OLEDs).In recent years,the chiral TADF materials and CP-OLEDs have rapidly developed,but unfortunately,the dissymmetry factors(g)are far from the requirement of practical *** ideal emitters and devices should have both high efficiency and a g factor,or at least a balance between these two *** review gives an overview of recent progress in chiral TADF materials,with a particular focus on the chiral skeleton,CPL property and device ***,the molecular design concept,device structure and methods to improve the g factors of chiral materials and CP-OLEDs are also discussed.

关键词： chiral thermally activated delayed fluorescence material chiral skeleton circularly polarized luminescence circularly polarized organic light-emitting diodes dissymmetry factor

A Quick Calculation Method for Radiation Pattern of Submillimeter Telescope with Deformation and Displacement

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Research in Astronomy and Astrophysics 2024年第3期24卷 249-265页

作者： Jia you yi-Wei Yao Zheng Wang School of Automation Southeast UniversityNanjing 210096China

Radiation pattern captures the electromagnetic performance of reflector antennas,which is significantly affected by the deformation of the primary reflector due to gravity and the displacement of the secondary *** the design process of large reflector antennas,a substantial amount of time is often dedicated to iteratively adjusting structural parameters and validating electromagnetic *** improve the efficiency of the design process,we first propose an approximate calculation method of optical path difference(OPD)for the deformation of the primary reflector under gravity and the displacement of the secondary *** an OPD fitting function based on the modified Zernike polynomials is proposed to capture the phase difference of radiation over the aperture plane,based on which the radiation pattern will be obtained quickly by the aperture field integration *** experiments demonstrate the effectiveness of the proposed quick calculation method for analyzing the radiation pattern of a 10.4 m submillimeter telescope antenna at its highest operating frequency of 856 *** comparison with the numerical simulation method based on GRASP(which is an antenna electromagnetic analysis tool combining physical optics(PO)and physical theory of diffraction(PTD)),the quick calculation method reduces the time for radiation pattern analysis from more than one hour to less than two ***,the quick calculation method exhibits excellent accuracy for the figure of merit(FOM)of the radiation ***,the proposed quick calculation method can obtain the radiation pattern with high speed and *** to the time-consuming numerical simulation method(PO and PTD),it can be employed for quick analysis of the radiation pattern for the lateral displacement of the secondary reflector and the deformation of the primary reflector under gravity in the design process of a reflector antenna.

关键词： instrumentation high angular resolution-methods data analysis-methods analytical

Ultrahigh spatiotemporal resolution beam signal reconstruction with bunch phase compensation

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Nuclear Science and Techniques 2024年第5期35卷 99-108页

作者： you-Ming Deng Yong-Bin Leng Xing-yi Xu Jian Chen yi-Mei Zhou Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of the Chinese Academy of Sciences Beijing 100049China Shanghai Synchrotron Radiation Facility Chinese Academy of SciencesShanghai 201204China University of Science and Technology of China Hefei 230026China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China

Various electromagnetic signals are excited by the beam in the acceleration and beam-diagnostic elements of a particle *** is important to obtain time-domain waveforms of these signals with high temporal resolution for research,such as the study of beam–cavity interactions and bunch-by-bunch parameter ***,a signal reconstruction algorithm with ultrahigh spatiotemporal resolution and bunch phase compensation based on equivalent sampling is proposed in this *** with traditional equivalent sampling,the use of phase compensation and setting the bunch signal zero-crossing point as the time reference can construct a more accurate reconstructed *** basic principles of the method,simulation,and experimental comparison are also *** on the beam test platform of the Shanghai Synchrotron Radiation Facility(SSRF)and the method of experimental verification,the factors that affect the reconstructed signal quality are analyzed and discussed,including the depth of the sampled data,quantization noise of analog-to-digital converter,beam transverse oscillation,and longitudinal *** results of the beam experiments show that under the user operation conditions of the SSRF,a beam excitation signal with an amplitude uncertainty of 2%can be reconstructed.

关键词： Turn-by-turn bunch phase compensation technique Equivalent sampling Signal reconstruction algorithm Ultrahigh spatiotemporal resolution SSRF

Carbon efficiency modeling and optimization of solar-powered cellular networks

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Science China(Information Sciences) 2024年第5期67卷 228-243页

作者： Yuxi ZHAO Xiaohu GE Wen YAN Tao HAN yi zhong School of Electronic Information and Communications Huazhong University of Science and Technology Huawei Technology Co. Ltd.

As wireless communication traffic experiences rapid growth, the carbon emissions caused by the communication industry are also on the rise. To achieve “carbon neutrality”, researchers are considering the use of renewable energy sources to power cellular networks, thereby reducing carbon emissions. However, a challenge arises when using renewable energy, specifically owing to the unpredictable nature of both the energy consumption of the cellular network and the power generation from renewable sources. This inconsistency results in low renewable energy utilization and reduced carbon efficiency. Herein, we construct a carbon efficiency model of solar-powered cellular networks using practical data from solar radiation. We propose a mechanism that alternately optimizes the performance of the renewable energy network and the cellular network. This approach is based on convex optimization theory and the Dinkelback algorithm, and it leads to the design of a carbon efficiency optimization algorithm. This algorithm aims to improve the carbon efficiency of cellular networks and reduce their carbon emissions. Simulation results demonstrate that our optimization scheme yields a maximum improvement of 2.56 × 108bps/g in the carbon efficiency of the cellular network as compared to conventional power allocation schemes such as the traditional water filling method and heuristic energy sharing and charge/discharge algorithms.

关键词： cellular networks renewable energy carbon efficiency convex optimization theory dinkelbach

Reliable calculations of nuclear binding energies by the Gaussian process of machine learning

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Nuclear Science and Techniques 2024年第6期35卷 130-144页

作者： Zi-yi Yuan Dong Bai Zhen Wang zhong-Zhou Ren School of Physics Science and Engineering Tongji UniversityShanghai 200092China College of Science Hohai UniversityNanjing 211100China Key Laboratory of Advanced Micro-Structure Materials Ministry of EducationShanghai 200092China

Reliable calculations of nuclear binding energies are crucial for advancing the research of nuclear physics. Machine learning provides an innovative approach to exploring complex physical problems. In this study, the nuclear binding energies are modeled directly using a machine-learning method called the Gaussian process. First, the binding energies for 2238 nuclei with Z > 20 and N > 20 are calculated using the Gaussian process in a physically motivated feature space, yielding an average deviation of 0.046 MeV and a standard deviation of 0.066 MeV. The results show the good learning ability of the Gaussian process in the studies of binding energies. Then, the predictive power of the Gaussian process is studied by calculating the binding energies for 108 nuclei newly included in AME2020. The theoretical results are in good agreement with the experimental data, reflecting the good predictive power of the Gaussian process. Moreover, the α-decay energies for 1169 nuclei with 50 ≤ Z ≤ 110 are derived from the theoretical binding energies calculated using the Gaussian process. The average deviation and the standard deviation are, respectively, 0.047 MeV and 0.070 MeV. Noticeably, the calculated α-decay energies for the two new isotopes ^ (204 )Ac(Huang et al. Phys Lett B 834, 137484(2022)) and ^ (207) Th(Yang et al. Phys Rev C 105, L051302(2022)) agree well with the latest experimental data. These results demonstrate that the Gaussian process is reliable for the calculations of nuclear binding energies. Finally, the α-decay properties of some unknown actinide nuclei are predicted using the Gaussian process. The predicted results can be useful guides for future research on binding energies and α-decay properties.

关键词： Nuclear binding energies decay Machine learning Gaussian process

Viscoacoustic generalized screen propagator in constant-Q model

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Petroleum Science 2024年第4期21卷 2356-2369页

作者： zhong-Kui Dai Jia-Chun you Xing-Guo Huang Wei Liu College of Geophysics Chengdu University of Technology College of Instrumentation and Electrical Engineering Jilin University

When seismic waves propagate through the geological formation, there is a significant loss of energy and a decrease in imaging resolution, because of the viscoacoustic properties of subsurface medium. This profoundly impacts seismic wavefield propagation, imaging and interpretation. To accurately image the true structure of subsurface medium, the consensus among geophysicists is to no longer treat subsurface medium as ideal homogeneous medium, but rather to incorporate the viscoacoustic properties of subsurface medium. Based on the generalized screen propagator using conventional acoustic wave equation(acoustic GSP), our developed method introduces viscoacoustic compensation strategy, and derives a one-way wave generalized screen propagator based on time-fractional viscoacoustic wave equation(viscoacoustic GSP). In numerical experiments, we conducted tests on two-dimensional multi-layer model and the Marmousi model. When comparing with the acoustic GSP using the acoustic data, we found that the imaging results of the viscoacoustic GSP using the viscoacoustic data showed a significant attenuation compensation effect, and achieved imaging results for both algorithms were essentially consistent. However, the imaging results of acoustic GSP using viscoacoustic data showed significant attenuation effects, especially for deep subsurface imaging. This indicates that we have proposed an effective method to compensate the attenuated seismic wavefield. Our application on a set of real seismic data demonstrated that the imaging performance of our proposed method in local areas surpassed that of the conventional acoustic GSP. This suggests that our proposed method holds practical value and can more accurately image real subsurface structures while enhancing imaging resolution compared with the conventional acoustic GSP. Finally, with respect to computational efficiency, we gathered statistics on running time to compare our proposed method with conventional Q-RTM, and it is evid

关键词： One-way wave equation Viscoacoustic wave equation Generalized screen propagator Attenuation and dispersion effects

Chiral transfer amidst one-dimensional linear polymers and twodimensional network covalent organic frameworks:Striking a fine balance between helicity and crystallinity

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Nano Research 2024年第6期17卷 5726-5734页

作者： Xinlin Zha Mengjuan Zuo Guilin Xu zhong Yan Haining you yi Xiong ying Liu yingying Li Liyan Yang Ke Liu Mufang Li Tao Zhao Dong Wang College of Chemistry and Chemical Engineering Donghua UniversityShanghai 201620China Key Laboratory of Textile Fiber and Products Ministry of EducationWuhan Textile UniversityWuhan 430200China

The current landscape of chiral covalent organic frameworks(COFs)predominantly centered on constructing asymmetric molecular-scale chirality,often introducing an inherent contradiction to the COF symmetry and limiting ***,we overcome these challenges by achieving chiral transfer between one-dimensional(1D)imine linear polymers(LPs)and two-dimensional(2D)networkβ-ketoenamine COFs composed of achiral *** successfully synthesize several 1D imine LPs with mesoscopic helical chirality,comprising achiral C2-symmetric terephthalaldehyde and diamine linkers in a chiral supramolecular transcription *** the irreversible tautomerism mechanism within the linker replacement approach,terephthalaldehyde(TPA)units in these helical 1D LPs are substituted with C3-symmetric 1,3,5-triformylphloroglucinol(TP),yielding the corresponding 2D networkβ-ketoenamine *** and helicity of the resultantβ-ketoenamine COFs intimately hinge on reaction conditions,including the aldehyde stoichiometry of Tp and TPA,as well as the quantity and concentration of the catalyst *** optimized conditions,the nucleation and growth were precisely governed,achieving a harmonious equilibrium of crystallinity and helicity within the generated 2D networkβ-ketoenamine COFs,even with covalent bond rupture,recombination,and topological transition(from[C2+C2]to[C3+C2]).Impressively,the ground state chirality inherent to helical 1D LPs seamlessly transfers to helical 2D networkβ-ketoenamine *** study not only offers new perspectives on the development of chiral functional COFs,but also provides fresh insights into the precise control of COFs'microscopic morphology.

关键词： chiral covalent organic frameworks chiral transfer dimensional transformation helicity

Energy consumption optimization for edge computing-supported cellular networks based on optimal transport theory

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Science China(Information Sciences) 2024年第2期67卷 201-218页

作者： Xiangyu LV Xiaohu GE yi zhong Qiang LI Yong XIAO School of Electronic Information and Communications Huazhong University of Science and Technology

With advancements in mobile communication technologies, there have been multiple user device(UD) connections to cellular networks. Because of changes in the spatial distribution of UDs and application requirements, the traditional offloading mechanism based on the nearest distance will result in heavy loads for some base stations(BSs). Because there is a high-order relationship between the energy consumption of the BS processing tasks and the number of computing tasks, the traditional offloading mechanism will result in high energy consumption, and UD’s offloading decision must be dynamically adjusted. The offloading decision of UDs is optimized based on detailed information about various parameters associated with a network from the standpoint of distribution. This information includes details regarding the spatial distribution of UDs,application requirements, and the offloading period of computing tasks. Based on optimal transport theory,an energy consumption optimization algorithm is suggested to lower the total amount of energy consumed by the offloading process of UDs’ computing tasks by reasonably planning the offloading BSs of the UDs in the networks. The simulation results show that the proposed offloading mechanism based on energy consumption optimization reduces the total energy consumption of the offloading process by 28.09% when compared to the traditional offloading mechanism, and the traffic managed by each BS is balanced.

关键词： optimal transport theory edge computing energy consumption reduction dynamic voltage frequency scaling