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Rescattering of stimulated Raman side scattering in nonuniform plasmas

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Matter and Radiation at Extremes 2024年第5期9卷 68-76页

作者： S.Tan Q.Wang Y.Chen W.B.yao C.Z.Xiao J.f.Myatt School of Physics and Electronics Hunan UniversityChangsha 410082China Institute of Applied Physics and Computational Mathematics Beijing 100094China School of Electrical and Information Engineering Anhui University of Science and TechnologyHuainanAnhui 232001China Department of Electrical and Computer Engineering University of Alberta9211116 St.NWEdmontonAlberta T6G 1H9Canada

Rescattering of stimulated Raman side scattering(SRSS)is observed for the first time via two-dimensional(2D)particle-in-cell(PIC)*** construct a theoretical model for the rescattering process,which can predict the region of occurrence of mth-order SRSS and estimate its *** rescattering process is identified by the 2D PIC simulations under typical conditions of a direct-drive inertial confinement fusion *** electrons produced by second-order SRSS propagate nearly perpendicular to the density gradient and gain nearly the same energy as in first-order SRSS,but there is no cascade acceleration to produce superhot *** studies for a wide range of ignition conditions show that SRSS and associated rescatterings are robust and important processes in inertial confinement fusion.

关键词： nonuniform acceleration scattering

Uniqueness on Difference Operators of Meromorphic functions of Infinite Order

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Acta Mathematica Sinica,English Series 2024年第2期40卷 511-527页

作者： Hui LI Ming Liang fANG Xiao yao School of Science China University of Mining and TechnologyBeijing 100083P.R.China Institute of Mathematics Academy of Mathematics and System SciencesChinese Academy of SciencesBeijing 100190P.R.China School of Sciences Hangzhou Dianzi UniversityHangzhou 310012P.R.China School of Mathematical sciences and LPMC Nankai UniversityTianjin 300071P.R.China

We investigate the uniqueness problems of meromorphic functions and their difference operators by using a new *** is proved that if a non-constant meromorphic function f shares a non-zero constant and ∞ counting multiplicities with its difference operators Δcf(z) and Δ_(c)^(2)f(z), thenΔcf(z)≡Δ_(c)^(2)f(z).In particular,we give a difference analogue of a result of *** method has two distinct features:(ⅰ) It converts the relations between functions into the corresponding *** makes it possible to deal with the uniqueness problem by linear algebra and combinatorics.(ⅱ) It circumvents the obstacle of the difference logarithmic derivative lemma for meromorphic functions of infinite order,since this method does not depend on the growth of the ***,the idea in this paper can also be applied to the case for several variables.

关键词： Uniqueness meromorphic functions difference operators infinite order

A Galaxy Image Augmentation Method Based on few-shot Learning and Generative Adversarial Networks

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Research in Astronomy and Astrophysics 2024年第3期24卷 180-193页

作者： Yiqi yao Jinqu Zhang Ping Du Shuyu Dong School of Artificial Intelligence South China Normal UniversityFoshan 528225China School of Computer Science South China Normal UniversityGuangzhou 510631China Guangdong Construction Vocational Technology Institute Guangzhou 511500China

Galaxy morphology classifications based on machine learning are a typical technique to handle enormous amounts of astronomical observation data,but the key challenge is how to provide enough training data for the machine learning *** this article proposes an image data augmentation method that combines few-shot learning and generative adversarial *** Galaxy10 DECaLs data set is selected for the experiments with consistency,variance,and augmentation effects being *** popular networks,including AlexNet,VGG,and ResNet,are used as examples to study the effectiveness of different augmentation methods on galaxy morphology *** results show that the proposed method can generate galaxy images and can be used for expanding the classification model’s training *** to comparative studies,the best enhancement effect on model performance is obtained by generating a data set that is 0.5–1 time larger than the original data ***,different augmentation strategies have considerably varied effects on different types of ***-GAN achieved the best classification performance on the ResNet network for In-between Round Smooth Galaxies and Unbarred Loose Spiral Galaxies,with f1 Scores of 89.54%and 63.18%,*** comparison reveals that various data augmentation techniques have varied effects on different categories of galaxy morphology and machine learning ***,the best augmentation strategies for each galaxy category are suggested.

关键词： techniques image processing-galaxies structure-galaxies general

Low-permittivity LiLn(PO_(3))_(4)(Ln=La,Sm,Eu)dielectric ceramics for microwave/millimeter-wave communication

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Journal of Advanced Ceramics 2024年第5期13卷 602-620页

作者： Huanrong Tian Xiaohan Zhang Zidong Zhang yao Liu Haitao Wu Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) Shandong UniversityJinan 250061China School of Materials Science and Engineering Shandong UniversityJinan 250061China School of Environmental and Material Engineering Yantai UniversityYantai 264005China

The development of dielectric materials with low permittivity and low loss is a great challenge in wireless *** this study,LiLn(PO_(3))_(4)(Ln=La,Sm,Eu)ceramic systems were successfully prepared using the traditional solid-state method.X-ray diffraction analysis indicated that the LiLn(PO_(3))_(4)ceramics crystallized in a monoclinic structure when sintered at 850–940℃.The characteristic peak shifted to higher angles with variations in the Ln element,which was ascribed to a reduction in the cell *** analysis by structure refinement revealed that the reduction in the cell volume resulted from the decrease in chemical bond lengths and the compression of[LiO_(4)]and[PO_(4)]***,the LiLn(PO_(3))_(4)ceramic system displayed exceptional performance at low sintering temperatures(910–925℃),including a high quality factor(Q·f)of 41,607–75,968 GHz,low temperature coefficient of resonant frequency(τ_(f))ranging from−19.64 to−47.49 ppm/℃,low permittivity(ε_(r))between 5.04 and 5.26,and low density(3.04–3.26 g/cm^(3)).The application of Phillips–van Vechten–Levine(P–V–L)theory revealed that the increased Q·f value of the LiLn(PO_(3))_(4)systems can be attributed to the enhanced packing fraction,bond covalency,and lattice energy,and the stability of τ_(f) was associated with the increase in the bond ***,a prototype microstrip patch antenna using LiEu(PO_(3))_(4) ceramics was *** measurement results demonstrated excellent antenna performance with a bandwidth of 360 MHz and a peak gain of 5.11 dB at a central frequency of 5.08 ***,low-εr LiLn(PO_(3))_(4)ceramic systems are promising candidates for microwave/millimeter-wave communication.

关键词： low permittivity LiLn(PO_(3))_(4) microwave dielectric properties Phillips-van Vechten-Levine(P-V-L)theory microstrip patch antenna

Recent advances in MXene for terahertz applications

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Optoelectronics Letters 2024年第5期20卷 272-288页

作者： ZHANG Yongzhi JIANG Jiuxing yao Yongtao HE Xunjun Key Laboratory of Engineering Dielectric and Applications(Ministry of Education) School of Electrical and Electronic EngineeringHarbin University of Science and TechnologyHarbin 150080China College of Science Harbin University of Science and TechnologyHarbin 150080China National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin University of Science and TechnologyHarbin 150080China

Since first synthesized in 2011, MXenes have attracted extensive attention in many scientific fields as a new two-dimensional(2D) material because of the unique physical and chemical properties. Over the past decade, in particular, MXenes have obtained numerous exciting achievements in the field of terahertz applications. In this review, we first briefly introduce the MXene materials, such as the basic structure and main fabrication processes of MXenes. Then, we summarize the recent applications of MXene materials in various terahertz research areas, including terahertz modulation, terahertz absorption, terahertz shielding, terahertz communication, terahertz detection and terahertz generation, in which the representative results are presented. finally, we give an outlook on the future research directions of MXene materials and their potential applications.

关键词： terahertz directions absorption

Deep Learning based Efficient Edge Slicing for System Cost Minimization in Wireless Networks

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Journal of Communications and Information Networks 2024年第2期9卷 162-175页

作者： Wei Jiang Daquan feng Liping Qian yao Sun College of Information Engineering Zhejiang University of TechnologyHangzhou 310023China Shenzhen Key Laboratory of Digital Creative Technology Guangdong Province Engineering Laboratory for Digital Creative TechnologyCollege of Electronics and Information EngineeringShenzhen UniversityShenzhen 518060China James Watt School of Engineering University of GlasgowG128QQScotlandUK

It is widely recognized that the future wireless networks are able to efficiently slice heterogeneous resources to provide customized services for various use cases. However, it is challenging to meet the diverse requirements of ever-growing applications, especially the stringent requirements of numerous delay-sensitive and/or computation-intensive applications. To tackle this challenge, we should not only consider user admission control to cope with resource limitations, but also make resource management more intelligent and flexible to meet diverse service needs. Taking advantages of mobile edge computing(MEC)and network slicing, in this paper, we propose deep edge slicing(DES),to jointly optimize user admission control and resource scheduling with the aim of minimizing the system cost while guaranteeing multitudinous quality-of-service (QoS) requirements. Specifically, we first apply a deep reinforcement learning approach to select the optimal set of access users with different service requests for maximizing resource *** a deep learning algorithm is employed to predict traffic data for allocating the communication and computing resources to different slices in advance. finally, we realize the dynamic scheduling of heterogeneous resources by solving the optimization problem of minimizing the system cost. Simulation results demonstrate that DES can greatly reduce the system cost compared to other benchmarks.

关键词： deep learning mobile edge computing user admission control resource scheduling

Synthesis of betanin by expression of the core betalain biosynthetic pathway in carrot

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Horticultural Plant Journal 2024年第3期10卷 732-742页

作者： Bo Wang Yahui Wang Yuanjie Deng Quanhong yao Aisheng Xiong State Key Laboratory of Crop Genetics and Germplasm Enhancement College of HorticultureNanjing Agricultural UniversityNanjingJiangsu 210095China Shanghai Key Laboratory of Agricultural Genetics and Breeding Biotechnology Research Institute of Shanghai Academy of Agricultural ScienceShanghai 201106China

Betalain has received increased attention because of its high nutritional value and crucial physiological *** on the elucidation of its core biosynthetic pathway,betalain can be produced in additional plants by metabolic *** of betalain in carrot(Daucus carota L.)can improve its nutritional quality and economic value by extracting betalain from the fleshy root,non-edible part,and processing residue of *** this study,two different constructs,namely,pYB:mCD(AomelOS,BvCYP76AD1S,and BvDODA1S)and p YB:CDD(BvCYP76AD1S,BvDODA1S,and MjcDOPA5GTS),were introduced into carrot for betanin synthesis by Agrobacterium-mediated *** can be synthetized in both transgenic calli,and p YB:m CD-transgenic callus can be used to produce betacyanin by suspension ***,pYB:mCD-transgenic seedlings can synthetize betanin only by tyrosine *** p YB:CDD-transgenic lines can synthetize betanin in whole *** betanin content in fleshy root of pYB:CDD-transgenic carrot was(63.4±9)μg·g^(-1)fresh weight according to quantitative *** betanin-producing carrot plant materials can be used to synthesize betanin for industrial application or consumption as dietary sources.

关键词： Daucus carota L. Betanin Biosynthesis Metabolic engineering Biofortification

A new fluorocarbon adhesive:Inhibiting agglomeration during combustion of propellant via efficient f-Al_(2)O_(3) preignition reaction

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Carbon Energy 2024年第6期6卷 292-305页

作者： Qifa yao Min Xia Chao Wang fanzhi Yang Wei Yang Yunjun Luo School of Materials Science and Engineering Beijing Institute of TechnologyBeijingChina Key Laboratory of High Energy Density Materials Ministry of EducationBeijing Institute of TechnologyBeijingChina School of Aerospace Engineering Beijing Institute of TechnologyBeijingChina Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijingChina

Inhibiting the agglomeration of molten aluminum particles packed in the binder network is a promising scheme to achieve efficient combustion of solid *** this investigation,the hydroxyl-terminated structured fluorinated alcohol compound(PfD)was introduced to modify the traditional polyethylene glycol/polytetrahydrofuran block copolymerization(HTPE)binder;that is,a unique fluorinated polyether(fTPE)binder was synthesized by embedding fluorinated organic segments into the HTPE binder via crosslinking *** fTPE was applied in aluminum-based propellants for the first *** to the complete release of fluorinated organic active segments in the range of 300℃to 400℃,the burning rate of fTPEbased propellant increased from 4.07(0%PfD)to 6.36 mm/s(5%PfD),increased by 56.27%under 1 *** reaction heat of fTPE propellants increased from 5.95(0%PfD)to 7.18 MJ/kg(5%PfD)under 3.0 MPa,indicating that HTPE binder modified with PfD would be conducive to inhibiting the D90 of condensed combustion products(CCPs)dropped by 81.84%from 75.46(0%PfD)to 13.71μm(5%PfD)under 3.0 MPa,in consistent with the significant reduction of aluminum agglomerates observed on the quenched burning surface of the *** results demonstrated that a novel fTPE binder with PfD can release fluorinated organic active segments,which motivate preignition reaction with the alumina shell in the early stage of aluminum combustion,and then enhance the melting diffusion effect of aluminum to inhibit the agglomeration.

关键词： agglomeration characteristics aluminum particles combustion fluorine alcohol compounds HTPE propellants

Improved observation of colonized roots reveals the regulation of arbuscule development and senescence by drought stress in the arbuscular mycorrhizae of citrus

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Horticultural Plant Journal 2024年第2期10卷 425-436页

作者： Xilong Yin Wei Zhang Zengwei feng Guangda feng Honghui Zhu Qing yao College of Horticulture South China Agricultural UniversityKey Laboratory of Biology and Genetic Improvement of Horticultural Crops(South China)Ministry of Agriculture and Rural AffairsGuangdong Province Key Laboratory of Microbial Signals and Disease ControlGuangzhouGuangdong 510642China Key Laboratory of Agricultural Microbiomics and Precision Application Ministry of Agriculture and Rural AffairsGuangdong Provincial Key Laboratory of Microbial Culture Collection and ApplicationKey Laboratory of Agricultural MicrobiomicsState Key Laboratory of Applied Microbiology Southern ChinaGuangdong Microbial Culture Collection Center(GDMCC)Institute of MicrobiologyGuangdong Academy of SciencesGuangzhouGuangdong 510070China

Citrus is the typical mycorrhizal fruit tree species establishing symbiosis with arbuscular mycorrhizal (AM) fungi. However, arbuscule development and senescence in colonized citrus roots, especially in response to drought stress, remain unclear, which is mainly due to the difficulty in clearing and staining lignified roots with the conventional method. Here, we improved the observation of colonized roots of citrus plants with the sectioning method, which enabled the clear observation of AM fungal structures. furthermore, we investigated the effects of one week of drought stress on arbuscule development and senescence with the sectioning method. Microscopy observations indicated that drought stress significantly decreased mycorrhizal colonization (f%and M%) although it did not affect plant growth performance. fluorescence probes (WGA 488 and/or Nile red) revealed that drought stress inhibited arbuscule development by increasing the percentage of arbuscules at the early stage and decreasing the percentages of arbuscules at the midterm and mature stages. Meanwhile, drought stress accelerated arbuscule senescence, which was characterized by the increased accumulation of neutral lipids. Overall, the sectioning method developed in this study enables the in-depth investigation of arbuscule status, and drought stress can inhibit arbuscule development but accelerate arbuscule senescence in the colonized roots of citrus plants. This study paves the way to elaborately dissecting the arbuscule dynamics in the roots of fruit tree species in response to diverse abiotic stresses.

关键词： Arbuscular mycorrhizae Citrus Drought stress Arbuscule development Arbuscule senescence fruit tree species