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Chinese Physics B 2024年第9期33卷 433-442页

作者： Kaixuan Li Cheng Ning Ye Dong Chuang Xue institute of applied Physics and Computational Mathematics Beijing 100088China

For investigating efficiently the stagnation kinetic-process of Z-pinch,we develop a novel modified electrostatic implicit particle-in-cell algorithm in radial one-dimension for Z-pinch simulation in which a small-angle cumulative binary collision algorithm is *** our algorithm,the electric field in z-direction is solved by a parallel electrode-plate model,the azimuthal magnetic field is obtained by Ampere’s law,and the term for charged particle gyromotion is approximated by the cross product of the averaged velocity and magnetic *** simulation results of 2 MA deuterium plasma shell Zpinch,the mass-center implosion trajectory agrees generally with that obtained by one-dimensional MHD simulation,and the plasma current also closely aligns with the external *** phase space diagrams and radial-velocity probability distributions of ions and electrons are *** main kinetic characteristic of electron motion is thermal equilibrium and oscillation,which should be oscillated around the ions,while that of ion motion is implosion *** the region of stagnation radius,the radial-velocity probability distribution of ions transits from the non-equilibrium to equilibrium state with the current increasing,while of electrons is basically the equilibrium *** the initial ion density and current peak are not high enough,the ions may not reach their thermal equilibrium state through collisions even in its stagnation phase.

关键词： Z-pinch particle-in-cell ion heating charged particle collisions

Explaining the dynamics of the sub-relativistic electron third belt in the Earth's radiation belts by using medium Earth orbit satellite observations

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Earth and Planetary Physics 2024年第5期8卷 762-775页

作者： JiaLi Chen Hong Zou YuGuang Ye institute of Space Physics and applied Technology Peking University

The Earth's electron radiation belts typically exhibit a two-belt structure. However, observations from the Van Allen Probes revealed the existence of a three-belt structure. This structure consists of an inner belt, a slot region, a remnant belt, a “second slot,” and a new outer belt(or the “third belt”). The formation of the structure involves both the partial loss of the original outer belts and the formation of the third belts. These processes are likely associated with radial diffusion induced by ultra-low-frequency(ULF) waves. In this study, we mainly analyzed electron flux data from medium Earth orbit(MEO) navigation satellites M17–M19 to supplement the observational evidence for the sub-relativistic electron(～100–500 keV) three-belt structure. Evidence of substorm injections and ULF waves during the three-belt event was identified, suggesting they played significant roles in the formation and evolution of the third *** injections may introduce new electron populations to the third belt, whereas ULF waves may influence the evolution of the third belt through radial diffusion. Toward the end of the three-belt event, the compression of the magnetosphere by shocks may lead to the dropout of the third belt because of the magnetopause shadowing effect and outward radial diffusion, ultimately disrupting the three-belt structure. This study provides more evidence for the presence of a sub-relativistic electron three-belt structure and offers an analysis of the evolutionary mechanisms of the third belt, which may contribute to a comprehensive understanding of the electron three-belt structure in the radiation belts.

关键词： third belt sub-relativistic electrons three-belt structure radiation belts magnetic storms and substorms wave–particle interactions

INCOMPRESSIBLE LIMIT OF IDEAL MAGNETOHYDRODYNAMICS IN A DOMAIN WITH BOUNDARIES

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Acta Mathematica Scientia 2024年第4期44卷 1441-1465页

作者： Qiangchang JU Jiawei WANG institute of applied Physics and Computational Mathematics Beijing 100088China

We study the incompressible limit of classical solutions to compressible ideal magneto-hydrodynamics in a domain with a flat *** boundary condition is characteristic and the initial data is *** first establish the uniform existence of classical solutions with respect to the Mach ***,we prove that the solutions converge to the solution of the incompressible MHD *** particular,we obtain a stronger convergence result by using the dispersion of acoustic waves in the half space.

关键词： incompressible limit ideal MHD equations boundary condition general initial data

Study of damage behavior and repair effectiveness of patch repaired carbon fiber laminate under quasi-static indentation loading

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Defence Technology（防务技术） 2024年第4期34卷 29-41页

作者： Alok Kumar Chinmaya Kumar Sahoo A.Arockiarajan Department of applied Mechanics Indian Institute of Technology MadrasChennai 600036India

Damage caused due to low-velocity impacts in composites leads to substantial deterioration in their residual strength and eventually provokes structural *** work presents an experimental investigation on the effects of different patch and parent laminate stacking sequences on the enhancement of impact strength of Carbon Fiber Reinforced Polymers(CFRP)composites by utilising the adhesively bonded external patch repair *** evolution study is also performed with the aid of Acoustic Emission(AE).Two different quasi-isotropic configurations were selected for the parent laminate,viz.,[45°/45°/0°/0°]s and[45°/0°/45°/0°]*** Static Indentation(QSI)test was performed on both the pristine laminates,and damage areas were detected by using the C-scan inspection *** laminates were repaired by using a single-sided patch of two different configurations,viz.,[45°/45°/45°/45°]and[45°/0°/0°/45°],and employing a circular plug to fill the damaged *** different combinations of repaired laminates with two configurations of each parent and patch laminate were produced,which were further subjected to the QSI *** results reveal the effectiveness of the repair method,as all the repaired laminates show higher impact resistance compared to the respective pristine *** of[45°/0°/0°/45°]configuration when repaired by taking[45°/45°/0°/0°]s and[45°/0°/45°/0°]s as parents exhibited 68%and 73%higher peak loads,respectively,than the respective pristine ***,parent and patch of configuration[45°/0°/45°/0°]s and[45°/0°/0°/45°],respectively,attain the highest peak load,whereas[45°/45°/0°/0°]s and[45°/45°/45°/45°]combinations possess the most gradual decrease in the load.

关键词： Carbon fiber reinforced polymers(CFRP) Quasi-isotropic laminate Quasi static indentation(QSI) Acoustic emission(AE) Composite repair

Deep Broad Learning for Emotion Classification in Textual Conversations

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Tsinghua Science and Technology 2024年第2期29卷 481-491页

作者： Sancheng Peng Rong Zeng Hongzhan Liu Lihong Cao Guojun Wang Jianguo Xie Center for linguistics and applied linguistics and Laboratory of Language Engineering and ComputingGuangdong University of Foreign StudiesGuangzhou 510006China Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and Devices South China Normal UniversityGuangzhou 510006China School of Computer Science and Cyber Engineering Guangzhou UniversityGuangzhou 510006China Modern Education Technology Center Guangdong University of Foreign StudiesGuangzhou 510006China

Emotion classification in textual conversations focuses on classifying the emotion of each utterance from textual *** is becoming one of the most important tasks for natural language processing in recent ***,it is a challenging task for machines to conduct emotion classification in textual conversations because emotions rely heavily on textual *** address the challenge,we propose a method to classify emotion in textual conversations,by integrating the advantages of deep learning and broad learning,namely *** aims to provide a more effective solution to capture local contextual information(i.e.,utterance-level)in an utterance,as well as global contextual information(i.e.,speaker-level)in a conversation,based on Convolutional Neural Network(CNN),Bidirectional Long Short-Term Memory(Bi-LSTM),and broad *** experiments have been conducted on three public textual conversation datasets,which show that the context in both utterance-level and speaker-level is consistently beneficial to the performance of emotion *** addition,the results show that our proposed method outperforms the baseline methods on most of the testing datasets in weighted-average F1.

关键词： emotion classification textual conversation Convolutional Neural Network(CNN) Bidirectional Long Short-Term Memory(Bi-LSTM) broad learning

Introducing urea into tirapazamine derivatives to enhance anticancer therapy

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National Science Review 2024年第4期11卷 245-253页

作者： Yajun Xu Jianlin Lv Chaoying Kong Ya Liu Kun Wang Zhaohui Tang Xuesi Chen Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of Sciences School of applied Chemistry and Engineering University of Science and Technology of China

Tirapazamine（TPZ） has been approved for multiple clinical trials relying on its excellent anticancer ***,as a typical hypoxia-activated prodrug（HAP）,TPZ did not exhibit survival advantages in Phase Ⅲ clinical trials when used in combination therapy due to the insufficient hypoxia levels in patients' *** this study,to improve the therapeutic effects of TPZ,we first introduced urea to synthesize a series of urea-containing derivatives of *** urea-containing TPZ derivatives showed increased hypoxic cytotoxicity（9.51-30.85-fold） compared with TPZ,while maintaining hypoxic ***,one of these derivatives,showed 20-fold higher cytotoxicity than TPZ while maintaining a similar hypoxic cytotoxicity *** highly efficiently deliver TPZP to the tumors and reduce its side effects on healthy tissues,we further prepared TPZP into a nanodrug with fibrin-targeting ability:***4-NPs,a vascular disrupting agent,was used to increase the fibrin level within tumors and exacerbate tumor *** being combined with CA4-NPs,FT11-TPZP-NPs can accumulate in the hypoxia-aggravated tumors and activate sufficiently to kill tumor *** a single-dose treatment,FT11-TPZP-NPs+CA4-NPs showed a high inhibition rate of 98.1% against CT26 tumor models with an initial volume of ～480 mm3and four out of six tumors were completely eliminated;it thereby exerted a significant antitumor *** study provides a new strategy for improving the therapeutic effect of TPZ and other HAPs in anticancer therapy.

关键词： tirapazamine vascular disrupting agent hypoxia-activated prodrug combretastatin A4 urea

New grating compressor designs for XCELS and SEL-100 PW projects

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High Power Laser Science and Engineering 2024年第3期12卷 126-133页

作者： Efim Khazanov Gaponov-Grekhov institute of applied Physics of the Russian Academy of Sciences Niznij NovgorodRussia

The problem of optimizing the parameters of a laser pulse compressor consisting of four identical diffraction gratings is solved *** goal of optimization is to obtain maximum pulse power,completely excluding both beam clipping on gratings and the appearance of spurious diffraction *** analysis is carried out in a general form for an out-of-plane *** particular‘plane'cases attractive from a practical point of view are analyzed in more detail:a standard Treacy compressor(TC)and a compressor with an angle of incidence equal to the Littrow angle(LC).It is shown that in both cases the LC is superior to the ***,for 160-cm diffraction gratings,optimal LC design enables 107 PW for XCELS and 111 PW for SEL-100 PW,while optimal TC design enables 86 PW for both projects.

关键词： Littrow angle compressor multi-petawatt lasers Treacy compressor

Computational modelling of gas–liquid–solid multiphase free surface flow with and without evaporation

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Particuology 2024年第7期90卷 218-235页

作者： Huihuang Xia Marc Kamlah institute for applied Materials(IAM) Karlsruhe Institute of Technology(KIT)Hermann-von Helmholtz-Platz 176344 Eggenstein-LeopoldshafenGermany

Gas–liquid–solid multiphase systems are ubiquitous in engineering applications,*** printing,spray drying and *** a numerical framework for modelling these multiphase systems is of great *** improved,resolved computational fluid dynamics-discrete element method(CFD-DEM)framework is developed to model the multiphase free surface flow with and without *** improved capillary force model is developed to compute the capillary interactions for partially floating particles at a free *** well-known benchmark cases,namely drag coefficient calculation,the single sphere settling,and drafting-kissing-tumbling of two particles are conducted to validate the resolved CFD-DEM *** turns out that the resolved CFD-DEM model developed in this paper can accurately calculate the fluid–solid interactions and predict the trajectory of solid particles interacting with the liquid *** demonstrations,namely two particles moving along a free surface when the liquid phase evaporates,and particle transport and accumulations inside an evaporating sessile droplet show the performance of the resolved model.

关键词： Capillary force Discrete element method Liquid bridge Particle transport Resolved CFD-DEM Volume of fluid

Modularized viromimetic polymer nanoparticle vaccines(VPNVaxs) to elicit durable and effective humoral immune responses

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National Science Review 2024年第03期11卷 200-214页

作者： Zichao Huang Xinyu Zhuang Liping Liu Jiayu Zhao Sheng Ma Xinghui Si Zhenyi Zhu Fan Wu Ningyi Jin Mingyao Tian Wantong Song Xuesi Chen Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of Sciences School of applied Chemistry and Engineering University of Science and Technology of China Changchun Veterinary Research institute Chinese Academy of Agricultural Sciences Jilin Biomedical Polymers Engineering Laboratory State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences

Virus-like particle(VLP) vaccines had shown great potential during the COVID-19 pandemic, and was thought to be the next generation of antiviral vaccine technology due to viromimetic structures. However,the time-consuming and complicated processes in establishing a current recombinant-protein–based VLP vaccine has limited its quick launch to the out-bursting pandemic. To simplify and optimize VLP vaccine design, we herein report a kind of viromimetic polymer nanoparticle vaccine(VPNVax), with subunit receptor-binding domain(RBD) proteins conjugated to the surface of polyethylene glycol-b-polylactic acid(PEG-b-PLA) nanoparticles for vaccination against SARS-CoV-2. The preparation of VPNVax based on synthetic polymer particle and chemical post-conjugation makes it possible to rapidly replace the antigens and construct matched vaccines at the emergence of different viruses. Using this modular preparation system, we identified that VPNVax with surface protein coverage of 20%–25% had the best immunostimulatory activity, which could keep high levels of specific antibody titers over 5 months and induce virus neutralizing activity when combined with an aluminum adjuvant. Moreover, the polymer nano-vectors could be armed with more immune-adjuvant functions by loading immunostimulant agents or chemical chirality design. This VPNVax platform provides a novel kind of rapidly producing and efficient vaccine against different variants of SARS-CoV-2 as well as other viral pandemics.

关键词： vaccine polymer nanomaterials SARS-CoV-2

Structure of the mantle transition zone in the central and western parts of the North China Craton using the receiver function 3D Kirchhoff migration method

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Science China Earth Sciences 2024年第9期67卷 2783-2795页

作者： Min ZHU Qingju WU Jieyuan NING Ruiqing ZHANG institute of Geophysics China Earthquake AdministrationBeijing 100081China institute of Theoretical and applied Geophysics Peking UniversityBeijing 100871China

Using data from the regional broadband dense temporary array deployed by the ChinArray project,we applied the three-dimensional(3D)Kirchhoff migration method of the teleseismic P-wave receiver function to investigate discontinuity structures of the mantle transition zone(MTZ)in the central and western parts of the North China Craton(NCC)using a highresolution 3D velocity model of the East Asian *** results show that the 410-km discontinuity beneath the Datong Volcano is depressed by~10 km,indicating the presence of a high-temperature anomaly near the depth of 410 km,which is likely related to small-scale mantle upwelling caused by the dehydration of the stagnant Pacific Plate in the *** upwelling of hot material provides a heat source for surface magmatic *** the Bohai Bay Basin,significant subsidence of the 660-km discontinuity is observed,and the transition zone here is extensively ***’s suggested that the anomalies in this region are related to the stagnation of the Pacific slab in the *** the thickness of the transition zone west of the North-South Gravity Lineament appears normal,we propose that the subducting front of the Pacific slab did not cross the gravity lineament in the *** comparison,the small-scale subsidence of the 660-km discontinuity and the thickening of the MTZ observed north of the Hannuoba Volcano likely indicate that the slab crossed the gravity lineament at its turning point and remained in the ***,a local thickening of the MTZ is observed in the Dabie orogenic belt of the Qinling *** is believed to be a combined effect of lithospheric delamination into the transition zone in the lower Yangtze region and the stagnation of the Pacific Plate.

关键词： North China Craton Mantle transition zone Receiver function migration Datong Volcano