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Preparation of Long-range Ordered Nanostructures in Semicrystalline Diblock Copolymer Thin Films Using Micromolding
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作者 Peng Zhang Hai-ying Huang +5 位作者 Yu Chen Shun Yu Christina Krywka Sarathlal K.Vayalil Stephan V.Roth 何天白 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2014年第9期1188-1198,共11页
Long-range ordered nanostructures are prepared in the poly(styrene)-block-poly(e-caprolactone) diblock copolymer thin films using micromolding. We evaluated the change in crystallinity based on grazing-incidence X... Long-range ordered nanostructures are prepared in the poly(styrene)-block-poly(e-caprolactone) diblock copolymer thin films using micromolding. We evaluated the change in crystallinity based on grazing-incidence X-ray diffraction and proved that the crystallinity increased with the decrease of the mold size. This means that ordered nanostructures with atomic length scale order can be adjusted by tuning the mesoscale confinement. The inherent mechanism was the cooperation of geometric confinement, microphase structure and surface-induced ordering of PS-b-PCL in the melt, which paved the way for the subsequent crystal growth. These findings establish a route to promote the cost-effective nanofabrication by combining the mature microfabrication technique with the emerging directed self-assembly of block copolymers. 展开更多
关键词 long-range ordered nanostructure Directed self-assembly Surface-induced ordering X-ray.
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Magnetic Long-Range Order and Colossal Magnetoresistance Effect in Double Exchange Ladders
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作者 MA Dong-Mei ZOU Liang-Jian 《Chinese Physics Letters》 SCIE CAS CSCD 2001年第9期1264-1267,共4页
By applying Bogoliubov's ineguality to double-exchange(DE) ladders, we show that the ferromagnetic(FM) order is absent in the new DE systems at finite temperatures. The incorporation of Jahn-Teller electron-phonon... By applying Bogoliubov's ineguality to double-exchange(DE) ladders, we show that the ferromagnetic(FM) order is absent in the new DE systems at finite temperatures. The incorporation of Jahn-Teller electron-phonon coupling, orbital degeneracy and on-site Coulomb interaction with the DE interaction do not preserve these orders. The long-wavelength thermal fluctuations of the spins oversome the DEFM correlation and destroy the FM orders. The implication of the absence of FM order on the transport of the DE ladders is discussed. 展开更多
关键词 orderS INTERACTION LADDER
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XAFS platform at NFPS BL17B at SSRF:extending structural characterization from long-range to short-range orders 被引量:1
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作者 Lan-Lu Lu Wen-Ming Qin +13 位作者 Luo-Zhen Jiang Yang Liu Kang-Wen Bao Chun-Yu Li Zhong-Jie Zhu Yi-Jun Gu Jian-Chao Tang Qing-Jie Xiao Ting-Ting Wu Yu-Pu Zhang Wei-Zhe Zhang Shu-Yu Zhou Ya-Yun Yang Zheng Jiang 《Nuclear Science and Techniques》 2025年第11期95-108,共14页
The synchrotron radiation beamline BL17B of the National Facility for Protein Science(NFPS)in Shanghai,situated at the Shanghai Synchrotron Radiation Facility(SSRF),was originally designed for diffraction experiments ... The synchrotron radiation beamline BL17B of the National Facility for Protein Science(NFPS)in Shanghai,situated at the Shanghai Synchrotron Radiation Facility(SSRF),was originally designed for diffraction experiments and accommodates techniques including single-crystal diffraction,powder diffraction,and grazing-incidence wide-angle X-ray scattering(GIWAXS)to enable the characterization of long-range ordered atomic structures.The academic community associated with BL17B engages in research domains encompassing biology,environment,energy,and materials,and a pronounced demand for characterizing short-range ordered structures exists.To address these requirements,BL17B established an advanced X-ray absorption fine structure(XAFS)experimental platform that enabled it to address a wide range of systems,from crystalline to amorphous and from long-range order to short-range order.The XAFS platform allows simultaneous XAFS data acquisition for both the transmission and fluorescence modes within an energy range of 5-23 keV,encompassing the K-edges of titanium to ruthenium and the L3-edges of cesium to bismuth.The platform exemplifies high levels of automation achieved through automated sample assessment and data collection based on large-capacity sample wheels that facilitate remote sample loading.When integrated with a highly integrated control system that simplifies experimental preparation and data collection,the XAFS platform significantly bolsters experimental efficiency and enhances user experience.Notably,the platform boasts an impressively low extended X-ray absorption fine structure(EXAFS)detection limit of 0.04 wt%for dilute copper phthalocyanine(CuPc)samples and an even more remarkable X-ray absorption near edge structure(XANES)detection threshold of 0.01 wt%.These results demonstrate the methodology?s reliability in low-concentration sample analysis,confirming its capability to generate high-quality XAFS data. 展开更多
关键词 XAFS Synchrotron radiation Short-range order
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Exploring temperature-driven phase dynamics of phosphate:The periodic to incommensurately modulated long-range ordered phase transition in CsCdPO_(4)
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作者 Mengjia Luo Yi Qiu Zhengyang Zhou 《Chinese Journal of Structural Chemistry》 2025年第1期18-20,共3页
The study of temperature-driven phase transitions is significant in phosphate chemistry,as these transitions often lead to unique physical properties for specific applications,such as catalysis,energy storage,ion cond... The study of temperature-driven phase transitions is significant in phosphate chemistry,as these transitions often lead to unique physical properties for specific applications,such as catalysis,energy storage,ion conduction,and nonlinear optics[1–3].The phase transition from room temperature(RT)to high temperature(HT)in phosphates is always from periodic structures to disordered or amorphous states[4–8].At RT,phosphates often maintain a highly ordered crystalline structure,which is stabilized by the lower thermal energy.As the temperature increases,the thermal energy disrupts the periodic arrangement of atoms and leads to a phase transition,where the once ordered structure becomes increasingly disordered or even amorphous. 展开更多
关键词 periodic structures phase transitions periodic structures disordered amorphous states nonlinear optics PHOSPHATE phase transition temperature driven phase transitions incommensurately modulated long range ordered phase
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RELATIONSHIP OF STRUCTURAL STABILITY AND LONG-RANGE-ORDER PARAMETER FOR STOICHIOMETRY NiAI
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作者 倪晓东 王西涛 陈国良 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 1996年第2期79+75-79,共6页
The relationship between the structural stability and the long-range-order parameter of stoichiometry NiAl has been studied using effective atom model based on the embedded-atom-method(EAM) potential. The results obta... The relationship between the structural stability and the long-range-order parameter of stoichiometry NiAl has been studied using effective atom model based on the embedded-atom-method(EAM) potential. The results obtained from the computation show that NiAl lacks a metastable disordered structure intrinsically, and has the stable ordered B2 phase,which are consistent with experimental results. 展开更多
关键词 NiAl intermetallic computer simulation order-disorder transformation
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Off-diagonal long-range order of the wave function in terms of the alternate molecular bonding geminals
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作者 吕文彩 孙家钟 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2000年第4期467-474,共8页
It is shown that in the quantum structural approach to high-Tc superconductivity, the wave function in terms of the alternate molecular bonding geminals possesses off-diagonal long-range order (ODLRO).
关键词 Alternate molecular bonding geminals quantum structural approach off-diagonal long-range order
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Existence of long-range magnetic order in Heisenberg spin nanoribbons with edge modification
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作者 Da-cheng Ma Ling-yi Cui +3 位作者 Chu-xiao Sun Xiao-dan Chi Zheng-Nan XianYu An Du 《Communications in Theoretical Physics》 SCIE CAS CSCD 2024年第7期134-144,共11页
Long-range magnetic order appears on a side decorated Heisenberg spin nanoribbon at nonzero temperature,although no spontaneous magnetization exists in a one-or two-dimensional isotropic Heisenberg model at any nonzer... Long-range magnetic order appears on a side decorated Heisenberg spin nanoribbon at nonzero temperature,although no spontaneous magnetization exists in a one-or two-dimensional isotropic Heisenberg model at any nonzero temperature according to the Mermin-Wagner theorem.By use of the spin Green's function method,we calculated the magnetizations of Heisenberg nanoribbons decorated by side spins with single-ion anisotropy and found that the system exhibits a nonzero transition temperature,whether the decorated edge spins of the system link together or separate from each other.When the width of the nanoribbon achieves infinite limit,the transition temperatures of the system tend to the same finite constant eventually whether one edge or both edges are decorated by side spins in the nanoribbon.The results reveal that the magnetism of a low-dimensional spin system is different from that of a threedimensional spin system.When the single-ion anisotropy of edge spins in a Heisenberg spin nanoribbon can be modulated by an electric field experimentally,various useful long-range magnetic orders of the system can be obtained.This work can provide a detailed theoretical basis for designing and fabricating next-generation low-dimensional magnetic random-access memory. 展开更多
关键词 NANORIBBON magnetic anisotropy long-range magnetic order Heisenberg model transition temperature
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Ti_(3)C_(2)T_(x) MXene-mediating near-and long-range electronic effect on atomically dispersed Co for efficient lithium-sulfur batteries
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作者 Haiyan Wang Hucheng Zhang +6 位作者 Lijing Wang Yonghui Li Tianhao Zhang Zhansheng Lu Hao Jiang Chunzhong Li Jianji Wang 《Chinese Chemical Letters》 2025年第10期599-606,共8页
Sluggish sulfur conversion kinetics pose an ongoing challenge in lithium-sulfur batteries(LSBs).Here,we present a solution through far-reaching long-range electronic regulation(LRER)on single-atom active sites.N-doped... Sluggish sulfur conversion kinetics pose an ongoing challenge in lithium-sulfur batteries(LSBs).Here,we present a solution through far-reaching long-range electronic regulation(LRER)on single-atom active sites.N-doped carbons(Co-NC)are implanted with densely-distributed Co single atoms,and supported on Ti_(3)C_(2)T_(x)MXene substrates to assemble 3D Co-NC/MXene catalyst.MXene effectively mediates interlayer charge transfer(~0.70|e|)contrasted with popular carbon materials(~0.06|e|)to produce LRER through surrounding carbon atoms.The synergy of LRER with near-range electronic regulation(NRER)tunes electronic structures,and enhances heterostructural stability,thus provoking desirous catalytic kinetics of Co single atoms in sulfur reduction.Thereby,the Co-NC/MXene/S cathodes exhibit impressive rate performance and excellent cycling stability(only 0.015%capacity decay per cycle over 600 cycles at 4 C)in LSBs,surpassing state-of-the-art sulfur cathodes.This work reveals the importance of LRER for improved catalysis,and provides new guidance to tailor heterostructures to achieve high-efficient catalysts in various process. 展开更多
关键词 Single-atom sites MXene HETEROSTRUCTURE long-range electronic regulation Lithium-sulfur batteries
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New insights into the long-range interaction mechanism of nitrogen reduction
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作者 Yumeng Cheng Wei Chen +1 位作者 Cheng He Wenxue Zhang 《Journal of Energy Chemistry》 2025年第7期842-851,共10页
Catalysts with asymmetric coordination exhibit excellent electrocatalytic activity due to changes in the active sites,which affect the arrangement of reactants and catalytic activity/selectivity.Hence,the exploration ... Catalysts with asymmetric coordination exhibit excellent electrocatalytic activity due to changes in the active sites,which affect the arrangement of reactants and catalytic activity/selectivity.Hence,the exploration of the inherent characteristics of active sites within diverse coordination environments holds great significance for the experimental design of catalytic structures.Single-atom catalysts(SACs)characterized by high coordination with four carbons(26 candidates)and low coordination with dinitrogen(27candidates)are constructed using nitrogen-doped graphdiyne derivatives(NGDY)as the substrate.Additionally,5 species of dual-atom catalysts(DACs)with coexistence of both high and low coordination sites are also developed and their nitrogen reduction reaction(NRR)activities are systematically investigated by density functional theory.The results indicate that metals with low coordination exhibit superior catalytic performance,such as Mo^(L)-NGDY(U_(L)=-0.30 V)and Nb^(L)-NGDY(U_(L)=-0.32 V).Furthermore,machine learning(ML)methods have deeply analyzed and elucidated the primary intrinsic characteristics that influence catalytic performance.These results not only unveil the underlying mechanisms behind the exceptional catalytic performance exhibited by low-coordination metal atoms,but also provide relevant and significant descriptors.More importantly,based on an investigation of the catalytic activity of a series of DACs,the“buffer and low-coordination accumulate”asymmetric coordination mechanism is proposed to unveil the long-range interactions between low and high coordination atoms.Due to this remote communication,MoNb-NGDY(U_(L)=-0.09/-0.37 V)exhibits the best NRR activity.This mechanism provides valuable insights into the origin of long-range bipartite interactions and inspires the design and synthesis of NRR catalysts with different coordination environments. 展开更多
关键词 Nitrogen reduction Asymmetric coordination DAC Machine learning long-range interactions
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Long-Range Admixture Linkage Disequilibrium and Allelic Responses of Sub1 and TPP7 under Consecutive Stress in Rice Validated Through Mendelian Randomization
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作者 Sabarinathan SELVARAJ Parameswaran CHIDAMBARANATHAN +8 位作者 Goutam Kumar DASH Priyadarsini SANGHAMITRA Kishor Pundlik JEUGHALE Cayalvizhi BALASUBRAMANIASAI Devraj LENKA Basavantraya Navadagi DEVANNA Seenichamy Rathinam PRABHUKARTHIKEYAN Sanghamitra SAMANTARAY Amaresh Kumar NAYAK 《Rice science》 2025年第5期704-716,I0095-I0117,共36页
Consecutive stresses,such as initial submergence during germination followed by water deficit during the seedling stage,pose significant challenges to direct-seeded rice cultivation.By Linkage disequilibrium analysis,... Consecutive stresses,such as initial submergence during germination followed by water deficit during the seedling stage,pose significant challenges to direct-seeded rice cultivation.By Linkage disequilibrium analysis,Sub1 and Dro1(Δbp:10 Mb),as well as Sub1 and TPP7(Δbp:6 Mb)were identified to exhibit long-range linkage disequilibrium(LRLD).Meta-QTL analysis further revealed that Sub1 and TPP7 co-segregated for tolerance to submergence at the germination and seedling stages.Based on this,we hypothesized that LRLD might influence plant responses to consecutive stresses.To test this hypothesis,we developed a structured recombinant inbred line population from a cross between Bhalum 2 and Nagina 22,with alleles(Sub1 and TPP7)in linkage equilibrium.Mendelian randomization analysis validated that the parental alleles,rather than the recombinant alleles of Sub1 and TPP7,significantly influenced 13 out of 41 traits under consecutive stress conditions.Additionally,16 minor additive effect QTLs were detected between the genomic regions,spanning Sub1 and TPP7 for various traits.A single allele difference between these genomic regions enhanced crown root number,root dry weight,and specific root area by 11.45%,15.69%,and 33.15%,respectively,under flooded germination conditions.Candidate gene analysis identified WAK79 and MRLK59 as regulators of stress responses during flooded germination,recovery,and subsequent water deficit conditions.These findings highlight the critical role of parental allele combinations and genomic regions between Sub1 and TPP7 in regulating the stress responses under consecutive stresses.Favourable haplotypes derived from these alleles can be utilized to improve stress resilience in direct-seeded rice. 展开更多
关键词 anaerobic germination consecutive stress long-range linkage disequilibrium RICE water deficit Mendelian randomization
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Probing dynamic interference in high-order harmonic generation from long-range molecular ion:Bohmian trajectory investigation
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作者 王俊 王兵兵 +5 位作者 郭福明 李苏宇 丁大军 陈基根 曾思良 杨玉军 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第5期233-237,共5页
Using Bohmlan trajectory (151) method, we investigate the dynamic interference in nlgn-orcter narmonlc generauon from diatomic molecular ions. It is demonstrated that the main characteristics of the molecular harmon... Using Bohmlan trajectory (151) method, we investigate the dynamic interference in nlgn-orcter narmonlc generauon from diatomic molecular ions. It is demonstrated that the main characteristics of the molecular harmonic spectrum can be well reproduced by only two BTs which are located at the two ions. This haiapens because these two localized trajectories can receive and store the whole collision information coming from all of the other re-collision trajectories. Therefore, the amplitudes and frequencies of these two trajectories represent the intensity and frequency distribution of the harmonic generation. Moreover, the interference between these two trajectories shows a dip in the harmonic spectrum, which reveals the molecular structure information. 展开更多
关键词 Bohmian trajectory molecular high-order harmonic generation dynamic interference
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Ultra-tight GPS/INS integration based long-range rocket projectile navigation method 被引量:4
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作者 赵捍东 李志鹏 张会锁 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第2期153-160,共8页
Accurate navigation is important for long-range rocket projectile's precise striking. To obtain stable and high-per- formance navigation result, a ultra-tight global positioning system/inertial navigation system (GP... Accurate navigation is important for long-range rocket projectile's precise striking. To obtain stable and high-per- formance navigation result, a ultra-tight global positioning system/inertial navigation system (GPS/INS) integration based nav- igation approach is proposed. The accurate short-time output of INS is used by GPS receiver to assist in acquisition of signal, and output information of INS and GPS is fused based on federated filter. Meanwhile, the improved cubature Kalman filter with strong tracking ability is chosen to serve as the local filter, and then the federated filter is enhanced based on vector sharing theory. Finally, simulation results show that the navigation accuracy with the proposed method is higher than that with traditional methods. It provides reference for long-range rocket projectile navigation. 展开更多
关键词 long-range rocket projectile global position system inertial measuring unit ultra-tight integration
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In- and Anti-transition of Firing Patterns Induced by Random Long-range Connections in Coupled Hindmarsh-Rose Neurons System 被引量:1
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作者 王鹏 张季谦 任海林 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第1期23-29,I0001,共8页
The effects of random long-range connections (shortcuts) on the transitions of neural firing patterns in coupled Hindmarsh-Rose neurons are investigated, where each neuron is subjected to an external current. It is ... The effects of random long-range connections (shortcuts) on the transitions of neural firing patterns in coupled Hindmarsh-Rose neurons are investigated, where each neuron is subjected to an external current. It is found that, on one hand, the system can achieve the transition of neural firing patterns from the fewer-period state to the multi-period one, when the number of the added shortcuts in the neural network is greater than a threshold value, indicating the occurrence of in-transition of neural firing patterns. On the other hand, for a stronger coupling strength, we can also find the similar but reverse results by adding some proper random connections. In addition, the influences of system size and coupling strength on such transition behavior, as well as the internality between the transition degree of firing patterns and its critical characteristics for different external stimulation current, are also discussed. 展开更多
关键词 In- and anti-transition Random long-range connection Firing pattern System size
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Ag、Cu、Au、Ni、Pd、Pt的Long-range Finis-Sinclair势构建及其二元合金形成焓的计算
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作者 刘艳侠 顾慧 +2 位作者 刘磊 孙佳佳 高岩 《辽宁大学学报(自然科学版)》 CAS 2009年第3期193-196,共4页
构建了fcc金属Cu、Ag、Au、Ni、Pd、Pt的Long-range Finnis-Sinclair势,并利用晶格常数、体弹性模量和金属的内聚能的实验数据拟合了这几种金属的Long-range Finnis-Sinclair势参数;利用Miedema理论和所构建的原子间相互作用势计算了Cu,... 构建了fcc金属Cu、Ag、Au、Ni、Pd、Pt的Long-range Finnis-Sinclair势,并利用晶格常数、体弹性模量和金属的内聚能的实验数据拟合了这几种金属的Long-range Finnis-Sinclair势参数;利用Miedema理论和所构建的原子间相互作用势计算了Cu,Ag,Au,Ni,Pd,Pt的二元合金的形成焓.对两种计算结果进行了比较,并与已有的实验结果进行了比较.结果表明,使用Long-range Finnis-Sinclair势计算合金的形成焓能够得到令人满意的结果. 展开更多
关键词 long-range Finnis-Sinclair势 MIEDEMA理论 形成焓
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SwinFusion: Cross-domain Long-range Learning for General Image Fusion via Swin Transformer 被引量:65
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作者 Jiayi Ma Linfeng Tang +3 位作者 Fan Fan Jun Huang Xiaoguang Mei Yong Ma 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第7期1200-1217,共18页
This study proposes a novel general image fusion framework based on cross-domain long-range learning and Swin Transformer,termed as SwinFusion.On the one hand,an attention-guided cross-domain module is devised to achi... This study proposes a novel general image fusion framework based on cross-domain long-range learning and Swin Transformer,termed as SwinFusion.On the one hand,an attention-guided cross-domain module is devised to achieve sufficient integration of complementary information and global interaction.More specifically,the proposed method involves an intra-domain fusion unit based on self-attention and an interdomain fusion unit based on cross-attention,which mine and integrate long dependencies within the same domain and across domains.Through long-range dependency modeling,the network is able to fully implement domain-specific information extraction and cross-domain complementary information integration as well as maintaining the appropriate apparent intensity from a global perspective.In particular,we introduce the shifted windows mechanism into the self-attention and cross-attention,which allows our model to receive images with arbitrary sizes.On the other hand,the multi-scene image fusion problems are generalized to a unified framework with structure maintenance,detail preservation,and proper intensity control.Moreover,an elaborate loss function,consisting of SSIM loss,texture loss,and intensity loss,drives the network to preserve abundant texture details and structural information,as well as presenting optimal apparent intensity.Extensive experiments on both multi-modal image fusion and digital photography image fusion demonstrate the superiority of our SwinFusion compared to the state-of-theart unified image fusion algorithms and task-specific alternatives.Implementation code and pre-trained weights can be accessed at https://github.com/Linfeng-Tang/SwinFusion. 展开更多
关键词 Cross-domain long-range learning image fusion Swin transformer
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Impact of radiations on the long-range correlation of soil moisture: A case study of the A’rou superstation in the Heihe River Basin 被引量:2
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作者 ZHANG Ting SHEN Shi CHENG Changxiu 《Journal of Geographical Sciences》 SCIE CSCD 2019年第9期1491-1506,共16页
Analyses of the soil moisture evolution trend and the influence of different types of radiation on soil moisture are of great significance to the simulation and prediction of soil moisture.In this paper,soil moisture(... Analyses of the soil moisture evolution trend and the influence of different types of radiation on soil moisture are of great significance to the simulation and prediction of soil moisture.In this paper,soil moisture(2–60 cm) and various radiation data from 2014–2015 at the A’rou superstation were selected.The radiation data include the net radiation(NR),shortwave and longwave radiation(SR and LR).Using adaptive fractal analysis(AFA),the long-range correlation(LRC) of soil moisture and long-range cross correlation(LRCC) between moisture and three types of radiation were analyzed at different timescales and soil depths.The results show that:(1) Persistence of soil moisture and consistency between soil moisture and radiation mutate at 18-d and 6-d timescales,respectively.The timescale variation of soil moisture persistence is mainly related to the influence process of radiation on soil moisture;(2) Both the soil moisture persistence and soil moisture-radiation consistency vary substantially with soil depth.The soil depth variation of soil moisture persistence is related to the influence intensity of radiation;(3) From 2–6 day timescales,LR displays the strongest influence on soil moisture at depths of 2–10 cm through negative feedback of radiation on the soil temperature.The influence intensity decreases with depth from 2–15 cm.Therefore,the soil moisture persistence is weak and increases with depth from 2–15 cm;and(4) At more than 6 day timescales,SR and NR display a stronger influence on the soil moisture persistence at depths of 2–40 cm through positive feedback of radiation on the soil temperature,especially at depths of 2–10 cm.This influence also weakens with depth.The soil moisture persistence at depths of 2–10 cm is the weakest and increases with depth from 2–40 cm.The research results are instructive for determining timescales and soil depths related to soil water in hydrological models. 展开更多
关键词 soil MOISTURE radiation long-range CORRELATION long-range cross CORRELATION adaptive FRACTAL analysis
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Stability and long-range correlation of air temperature in the Heihe River Basin 被引量:3
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作者 YANG Jing SU Kai YE Sijing 《Journal of Geographical Sciences》 SCIE CSCD 2019年第9期1462-1474,共13页
Air temperature(AT) is a subsystem of a complex climate.Long-range correlation(LRC) is an important feature of complexity.Our research attempt to evaluate AT’s complexity differences in different land-use types in th... Air temperature(AT) is a subsystem of a complex climate.Long-range correlation(LRC) is an important feature of complexity.Our research attempt to evaluate AT’s complexity differences in different land-use types in the Heihe River Basin(HRB) based on the stability and LRC.The results show the following:(1) AT’s stability presents differences in different land-use types.In agricultural land,there is no obvious variation in the trend throughout the year.Whereas in a desert,the variation in the trend is obvious: the AT is more stable in summer than it is in winter,with Ta ranges of [8,20]°C and SD of the AT residual ranges of [0.2,0.7],respectively.Additionally,in mountainous areas,when the altitude is beyond a certain value,AT’s stability changes.(2) AT’s LRC presents differences in different land-use types.In agricultural land,the long-range correlation of AT is the most persistent throughout the year,showing the smallest difference between summer and winter,with the Hs range of [0.8,1].Vegetation could be an important factor.In a desert,the long-range correlation of AT is less persistent,showing the greatest difference between summer and winter,with the Hs range of [0.54,0.96].Solar insolation could be a dominant factor.In an alpine meadow,the long-range correlation of AT is the least persistent throughout the year,presenting a smaller difference between summer and winter,with the Hs range of [0.6,0.85].Altitude could be an important factor.(3) Usually,LRC is a combination of the Ta and SD of the AT residuals.A larger Ta and smaller SD of the AT residual would be conducive to a more persistent LRC,whereas a smaller Ta and larger SD of the AT residual would limit the persistence of LRC.A larger Ta and SD of the AT residual would create persistence to a degree between those of the first two cases,as would a smaller Ta and SD of the AT residual.In addition,the last two cases might show the same LRC. 展开更多
关键词 Heihe RIVER BASIN air temperature long-range correlation STABILITY GEOGRAPHICAL environment
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Long-range electron synergy over Pt_(1)-Co_(1)/CN bimetallic single-atom catalyst in enhancing charge separation for photocatalytic hydrogen production 被引量:4
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作者 Man Yang Jing Mei +3 位作者 Yujing Ren Jie Cui Shuhua Liang Shaodong Sun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第6期502-509,I0011,共9页
The development of novel single-atom catalysts with optimal electron configuration and economical noble-metal cocatalyst for efficient photocatalytic hydrogen production is of great importance,but still challenging.He... The development of novel single-atom catalysts with optimal electron configuration and economical noble-metal cocatalyst for efficient photocatalytic hydrogen production is of great importance,but still challenging.Herein,we fabricate Pt and Co single-atom sites successively on polymeric carbon nitride(CN).In this Pt_(1)-Co_(1)/CN bimetallic single-atom catalyst,the noble-metal active sites are maximized,and the single-atomic Co_(1)N_4sites are tuned to Co_(1)N_3sites by photogenerated electrons arising from the introduced single-atomic Pt_(1)N_4sites.Mechanism studies and density functional theory(DFT)calculations reveal that the 3d orbitals of Co_(1)N_3single sites are filled with unpaired d-electrons,which lead to the improved visible-light response,carrier separation and charge migration for CN photocatalysts.Thereafter,the protons adsorption and activation are promoted.Taking this advantage of long-range electron synergy in bimetallic single atomic sites,the photocatalytic hydrogen evolution activity over Pt_(1)-Co_(1)/CN achieves 915.8 mmol g^(-1)Pt h^(-1),which is 19.8 times higher than Co_(1)/CN and 3.5 times higher to Pt_(1)/CN.While this electron-synergistic effect is not so efficient for Pt nanoclusters.These results demonstrate the synergistic effect at electron-level and provide electron-level guidance for the design of efficient photocatalysts. 展开更多
关键词 Bimetallic single-atom catalyst long-range electron synergy Charge separation/transfer Carbon nitride Hydrogen production
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Comprehensive compensation method for the influence of disturbing gravity field on long-range rocket guidance computing 被引量:2
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作者 Yansheng WU Zongqiang WANG Bing ZHANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第3期408-418,共11页
With the improvement of the accuracy of the inertial system,the influence of the disturbing gravity field on the accuracy of long-range rocket has become increasingly prominent.However,in actual engineering,there are ... With the improvement of the accuracy of the inertial system,the influence of the disturbing gravity field on the accuracy of long-range rocket has become increasingly prominent.However,in actual engineering,there are problems of low accuracy and being time-consuming for disturbing gravity field compensation.In view of this,this paper proposes a set of online comprehensive solutions combining disturbing gravity reconstruction and stellar correction.According to the pre-launch binding parameters,the net function assignment method is used in the navigation system to calculate disturbing gravity in the boost phase online.In the guidance system,a closed-loop guidance online compensation method is proposed based on the state-space perturbation method for the disturbing gravity in the coast phase.At the same time,the vertical deflection can also be corrected by stellar guidance.The calculation results are simulated and verified under different circumstances.Simulation results show that the proposed online compensation algorithm has an accuracy improvement compared with the element compensation algorithm on ground.And the stellar guidance algorithm can further correct the impact deviation.The impact deviation after comprehensive compensation does not exceed 50 m,and the compensation percentage is greater than 65%. 展开更多
关键词 Disturbing gravity field long-range rocket Online compensation Stellar guidance Vertical deflection
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An overview of emissions of SO2 and NOx and the long-range transport of oxidized sulfur and nitrogen pollutants in East Asia 被引量:8
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作者 Yu Qu Junling An +1 位作者 Youjiang He Jun Zheng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2016年第6期13-25,共13页
The long-range transport of oxidized sulfur(sulfur dioxide(SO2) and sulfate) and oxidized nitrogen(nitrogen oxides(NOx ) and nitrate) in East Asia is an area of increasing scientific interest and political con... The long-range transport of oxidized sulfur(sulfur dioxide(SO2) and sulfate) and oxidized nitrogen(nitrogen oxides(NOx ) and nitrate) in East Asia is an area of increasing scientific interest and political concern. This paper reviews various published papers, including ground- and satellite-based observations and numerical simulations. The aim is to assess the status of the anthropogenic emissions of SO2 and NOx and the long-range transport of oxidized S and N pollutants over source and downwind region. China has dominated the emissions of SO2 and NOx in East Asia and urgently needs to strengthen the control of their emissions, especially NOx emissions. Oxidized S and N pollutants emitted from China are transported to Korea and Japan, due to persistent westerly winds, in winter and spring.However, the total contributions of China to S and N pollutants across Korea and Japan were not found to be dominant over longer time scales(e.g., a year). The source–receptor relationships for oxidized S and N pollutants in East Asia varied widely among the different studies. This is because:(1) the nonlinear effects of atmospheric chemistry and deposition processes were not well considered, when calculating the source–receptor relationships;(2) different meteorological and emission data inputs and solution schemes for key physical and chemical processes were used; and(3) different temporal and spatial scales were employed. Therefore, simulations using the same input fields and similar model configurations would be of benefit, to further evaluate the source–receptor relationships of the oxidized S and N pollutants. 展开更多
关键词 long-range transport Sulfate Nitrate East Asia Source–receptor relationships
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