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基于忆阻器反馈的Lorenz超混沌系统及其电路实现

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物理学报 2016年第19期65卷 19-29页

作者：阮静雅孙克辉牟俊中南大学物理与电子学院长沙410083

采用二次型磁控忆阻器作为系统的正反馈项,设计了一个超混沌电路,建立了该系统的无量纲数学模型,探讨了忆阻器混沌系统与原混沌系统的不同之处.分析了系统的平衡点集和稳定性,发现系统继承了原系统的对称性,确定了系统参数所对应的稳定... 详细信息

采用二次型磁控忆阻器作为系统的正反馈项,设计了一个超混沌电路,建立了该系统的无量纲数学模型,探讨了忆阻器混沌系统与原混沌系统的不同之处.分析了系统的平衡点集和稳定性,发现系统继承了原系统的对称性,确定了系统参数所对应的稳定和不稳定区域分布,得到了系统的稳定和不稳定平衡点集.采用分岔图、Lyapunov指数谱、Poincaré截面等分析方法,研究了系统的动力学行为随系统参数和忆阻器初始状态而变化的情况,观察到了混沌系统随忆阻器初值不同引起的吸引子共存和状态转移现象,结合相图与谱熵算法分析了状态转移现象.设计并实现了该系统的模拟电子电路,实验结果表明,电路实验结果与数值仿真结果相吻合,为忆阻器混沌电路的实际应用奠定了基础.

关键词：忆阻器超混沌简化Lorenz系统吸引子共存

Interparticle energy transfer between NaNdF_(4) and NaYbF_(4) in self-assembled nanostructures

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Journal of Rare Earths 2024年第6期42卷 1029-1035,I0001页

作者： Xinyu Chen Haoze Yang Yuyang Gu Chenqing Wen Yishuo sun Jiaming ke Wei Feng Department of Chemistry and State key Laboratory of Molecular Engineering of Polymers Fudan University Shanghai200433China

Forster resonance energy transfer(FRET)is a widely used spectroscopic *** development of donor-acceptor combinations is essential to advance this *** make the energy transfer efficiency independent of the external environment,we explored the potential of constructing donor—acceptor combinations with lanthanide ion-doped nanoparticles(LNPs),in which the 4f electrons of the lanthanide ions are shielded by the 5s and 6p ***-radiative energy transfer between LNPs was demonstrated in self-assembled nanostructures and core-shell structure of LNPs was used to control the distance between donor and acceptor in self-assembled *** emission intensity ratio of donor and acceptor illustrates that the energy transfer efficiency decreases significantly with increasing distance and the effective energy transfer distance is 8.5 nm,showing the potential of using LNPs as donor-acceptor pairs in the construction of distance-dependent energy transfer system.

关键词： Lanthanide nanoparticles Self-assembly Energy transfer Distance Epitaxialgrowth Rare earths

Reasonable grazing may balance the conflict between grassland utilization and soil conservation in the semi-arid hilly areas, China

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Journal of Arid Land 2024年第8期16卷 1130-1146页

作者： sun hui ZHAO Yunge GAO Liqian XU Mingxiang College of Forestry Northwest A&F UniversityYangling 712100China College of Soil and Water Conservation Science and Engineering Institute of Soil and Water ConservationNorthwest A&F UniversityYangling 712100China

Soil erosion caused by unsustainable grazing is a major driver of grassland ecosystem degradation in many semi-arid hilly areas in ***,grazing exclusion is considered as an effective method for solving this issue in such ***,some ecological and economic problems,such as slow grassland rejuvenation and limited economic conditions,have become obstacles for the sustainable utilization of grassland ***,we hypothesized that the conflict between grassland use and soil conservation may be balanced by a reasonable grazing *** this study,a two-year grazing fence experiment with five grazing intensity gradients was conducted in a typical grassland of the Loess Plateau in China to evaluate the responses of vegetation characteristics and soil and water losses to grazing *** five grazing intensity gradients were 2.2,3.0,4.2,6.7,and 16.7 goats/hm2,which were represented by G1-G5,respectively,and no grazing was used as *** results showed that a reasonable grazing intensity was conducive to the sustainable utilization of grassland *** biomass under G1-G4 grazing intensity significantly increased by 51.9%,42.1%,36.9%,and 36.7%,respectively,compared with *** addition,vegetation coverage increased by 19.6%under G1 grazing *** diversity showed a single peak trend with increasing grazing *** Shannon-Wiener diversity index under G1-G4 grazing intensities significantly increased by 22.8%,22.5%,13.3%,and 8.3%,respectively,compared with ***,grazing increased the risk of soil *** with control,runoff yields under G1-G5 grazing intensities increased by 1.4,2.6,2.8,4.3,and 3.9 times,respectively,and sediment yields under G1-G5 grazing intensities were 3.0,13.0,20.8,34.3,and 37.7 times greater,respectively,than those under *** result was mainly attributed to a visible decrease in litter biomass after grazing,which decreased by 50.5%,72.6%,79.0%,80.0%

关键词： fence-controlled grazing rehabilitated grassland vegetation community characteristics soil erosion sediment biocrusts Loess Plateau

简化Lorenz多涡卷混沌吸引子的设计与应用

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物理学报 2014年第12期63卷 106-116页

作者：艾星星孙克辉贺少波王会海中南大学物理与电子学院长沙410083 新疆大学物理科学与技术学院乌鲁木齐830046

将简化Lorenz系统线性化成两个线性系统,采用控制方法得到两涡卷混沌系统,通过扩展两涡卷混沌系统的指标2鞍焦点,设计了多涡卷混沌吸引子.利用相图、分岔图、Poincaré截面和最大Lyapunov指数等方法,分析了该多涡卷混沌系统的动力学特性... 详细信息

将简化Lorenz系统线性化成两个线性系统,采用控制方法得到两涡卷混沌系统,通过扩展两涡卷混沌系统的指标2鞍焦点,设计了多涡卷混沌吸引子.利用相图、分岔图、Poincaré截面和最大Lyapunov指数等方法,分析了该多涡卷混沌系统的动力学特性.设计了多涡卷混沌吸引子的模拟电路,并进行了仿真,数值仿真与电路仿真相一致.将多涡卷混沌系统应用于图像加密,设计了多涡卷混沌与高级加密标准(AES)的改进混合加密算法,并分析了其加密性能.结果表明,基于多涡卷混沌系统的改进混合加密算法具有更高的安全性.

关键词：混沌多涡卷吸引子简化Lorenz系统图像加密

Review of GAN-Based Research on Chinese Character Font Generation

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Chinese Journal of Electronics 2024年第3期33卷 584-600页

作者： Xuanhong WANG Cong LI Zengguo sun Luying hui Xi'an University of Posts and Telecommunications School of Computer Science Shaanxi Normal University key Laboratory of Intelligent Computing and Service Technology for Folk Song Ministry of Culture and Tourism

With the rapid development of deep learning,generative adversarial network(GAN) has become a research hotspot in the field of computer *** has a wide range of applications in image *** by GAN,a series of models of Chinese character font generation have been proposed in recent *** this paper,the latest research progress of Chinese character font generation is analyzed and *** and its development history are ***-based methods for Chinese character font generation are clarified as well as their improvements,based on whether the specific elements of Chinese characters are *** public datasets used for font generation are summarized in detail,and various application scenarios of font generation are *** evaluation metrics of font generation are systematically summarized from both qualitative and quantitative *** paper contributes to the in-depth research on Chinese character font generation and has a positive effect on the inheritance and development of Chinese culture with Chinese characters as its carrier.

关键词： Generative adversarial network Font generation Image-to-image translation Deep learning

Designing ultrastrong and thermally stable FeCrAl alloys with the fine-grained structure

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Journal of Materials Science & Technology 2024年第4期171卷 198-208页

作者： Shuaiyang Liu Jinyu Zhang hui Wang Gang Liu Xiangdong Ding Jun sun State key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China Science and Technology on Reactor Fuel and Materials Laboratory Nuclear Power Institute of ChinaChengdu 610041China

Designing microstructurally stable FeCrAl alloys with excellent strength-ductility synergy is highly desir-able for their engineering ***,due to the preference nucleation of precipitates at grain boundaries(GBs),the improved precipitation strengthening of these alloys is usually accompanied by in-tergranular ***,we propose a novel thermomechanical processing route coupled with the Si alloying strategy via precipitation of coherent deformable Laves precipitates inside equiaxed fine-grains to achieve FeCrAl alloys with ultrahigh yield strength over∼992 MPa,excellent uniform elongation of∼7.6%at room temperature,and superior thermal stability at temperature∼1200℃.The Si alloying not only decreases the stacking fault energy of Laves precipitates favorable for their stacking-fault-mediated deformation but also hinders grain coarsening at 1200℃due to the Si-enrichment favorable for GB pin-ning *** results prove the possibility of achieving the collaborative enhancement of mutually exclusive properties in alloys,such as strength-ductility-thermal stability via nanoprecipitation engineer-ing,and offer a promising route to prepare dispersion-strengthened materials.

关键词： FeCrAl alloys Si alloying Mechanical properties Thermal stability Laves phase

Fairy shrimp Branchinella kugenumaensis displays sensitivity to microplastic exposure

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Journal of Oceanology and Limnology 2024年第4期42卷 1186-1199页

作者： Yingying ZHANG Xinrui XU Wenbo sun Yuting WANG hui YANG College of Animal Science and Technology Yangzhou UniversityYangzhou 225009China

The increasing global concern regarding plastic pollution has prompted the research into the consequences of microplastics(MPs)on aquatic *** shrimp Branchinella kugenumaensis are freshwater planktonic organisms that have existed for 250 million *** study aimed to uncover the harmful effects of MPs,with a particular focus on their size variations(0.1,1,and 5μm),on the fairy *** focused on how MPs could significantly affect the survival and growth of fairy ***,larger MPs,especially those measuring 5μm,caused higher mortality rates and hindered the growth compared to smaller *** impact of MPs continued even subsequent to depuration in clean *** accumulation of MPs within the intestines of fairy shrimp resulted in intestinal blockages,disrupted excretory functions,and harmed intestinal epithelial *** at the histological,cellular,and molecular levels showed that exposure to MPs triggered necroptosis in intestinal cells,accompanied by alterations in pathways related to transcription,translation,digestion,energy metabolism,and neurological ***,the effects of MPs on gene expression and pathways varied based on particle size,with larger MPs having a more significant effect and causing a strong response in xenobiotic biodegradation and metabolism *** suggest that the increasing severity of MPs pollution could pose a significant threat to the survival of fairy *** study provided vital insights into the complex relationship between microplastics and aquatic organisms,and highlighted the urgent need to address the potential devastating impact of plastic pollution on freshwater ***,due to their rapid growth,strong reproductive capacity,sensitivity,and ease of cultivation,fairy shrimp hold the potential candidate to serve as a model organism for studying the effects of MPs and other pollutants on freshwater ecosystems.

关键词： microplastic freshwater ecosystem toxic effects fairy shrimp model organism

A Novel Gymnosperm Wood from the Lopingian(Late Permian)in Zhangzi,Shanxi,North China and Its Paleoecological and Paleogeographic Implications

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Journal of Earth Science 2024年第1期35卷 167-176页

作者： Xiao Shi Jianxin Yu Yuewu sun Zhen Xu hui Li College of Earth Sciences Jilin UniversityChangchun 130061China International Center of Future Science Dinosaur Evolution Research CenterJilin UniversityChangchun 130012China State key Laboratory of Biogeology and Environmental Geology School of Earth SciencesChina University of GeosciencesWuhan 430074China Research Center of Palaeontology and Stratigraphy Jilin UniversityChangchun 130026China Jiangxi key Laboratory for Mass Spectrometry and Instrumentation East China University of TechnologyNanchang 330013China

The Permian-Triassic transition saw extreme climatic changes that severely impacted the terrestrial *** plants,particularly fossil woods,are sensitive to climatic changes,and they,therefore,are unique materials revealing extreme environmental and climatic changes on land at that *** conifer woods were discovered in the Lopingian(Late Permian)strata of the sunjiagou Formation in Shanxi Province,North *** newly finding permineralized woods record the unique landscape of Lopingian North *** represent a new conifer genus and species:Shanxiopitys zhangziensis *** *** of growth pattern and anatomical characteristics of the fossil woods indicate these trees grew under optimal growing conditions,and without seasonal growth ***,climate signals from leaf fossils,vertebrate fossils and sedimentary evidences indicate a strongly seasonal climate in North China during the ***,it is speculated that these trees likely lived in the gallery forests,which were distributed along the paleo-rivers within a seasonal landscape in the central North China block during the Lopingian.

关键词： Shanxiopitys zhangziensis gen.et sp.nov. wood ecology geography gallery forest Lopingian North China

Accurate characterization of bubble mixing uniformity in a circular region using computational geometric theory

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Particuology 2024年第3期86卷 149-159页

作者： hui sun Jianxin Xu Shibo Wang Guangcheng Cai Hua Wang Wuliang Yin State key Laboratory ofComplex Nonferrous Metal Resources Clean Utilization Kunming University ofScience and TechnologyKunming650093China bFaulty of Metallurgical and Energy Engineering Kunming University ofScience and TechnologyKunming650093China Faculty of Science Kunming University ofScience and TechnologyKunming650500China Department of Elec.and Electronic Engineering.University of Manchester ManchesterM139PL UK

The present study proposes a novel method based on the geometric theory for measuring the distribution of bubble swarms in the circular region of a direct-contact heat *** was determined that the mixing is uniform when the average distance between the bubble swarms in the unit circular region is approximately 0.9054,which is the standard reference *** effect of sample size(i.e.,the number of bubbles)on mixing uniformity was investigated to determine the optimal sample *** was verified that the metric's accuracy and stability were higher with a sample size of ***,it was proposed to increase the sample size by filling irregular bubbles using a segmentation method,which enabled a further accurate assessment of the mixing *** mixing uniformity of bubble swarms in the circular region and its maximum internal connection with the square region was accurately *** was revealed that the relative average error increased by approximately 3.47% due to information *** proposed method was demonstrated to be rotationally *** present study provided novel insights into evaluating mixing uniformity,which would guide enhanced heat transfer and the effective evaluation of the spatiotemporal characteristics of transient mixing in circular regions or the cross-sections of chemical transport pipelines.

关键词： Direct-contact heat exchanger Circular region Bubble swarm Distribution uniformity AD-Circle method