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Analysis of Histochemical Localization and Content Influencing Factors of Saponins in Pseudostellaria heterophylla
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作者 Huiqing PAN Yanda ZHANG +3 位作者 Zhenhua WANG Qi ZHAO Zuyun YE Xin WANG 《Medicinal Plant》 2026年第1期5-9,19,共6页
This paper provides a systematic review of the histochemical localization,content characteristics,and influencing factors of saponins in Pseudostellaria heterophylla based on an extensive literature survey.It provides... This paper provides a systematic review of the histochemical localization,content characteristics,and influencing factors of saponins in Pseudostellaria heterophylla based on an extensive literature survey.It provides an in-depth analysis and summary of the effects of biological factors,environmental conditions,agronomic practices,processing methods,and continuous cropping obstacles on the synthesis of P.heterophylla saponins,as well as their underlying mechanisms.Based on identified gaps in the current literature,future research directions and prospects are proposed.The findings of this review offer valuable insights for advancing the understanding of the saponin biosynthesis mechanisms in P.heterophylla and for enhancing its quality. 展开更多
关键词 Pseudostellaria heterophylla SAPONIN Histochemical localization Content influencing factors Research progress
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Mixed Local and Nonlocal Elliptic Problem with Concave-Convex and Discontinuous Nonlinearities
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作者 Yiru WANG Shuibo HUANG Qiaoyu TIAN 《Journal of Mathematical Research with Applications》 2026年第1期40-56,共17页
This paper investigates the following mixed local and nonlocal elliptic problem fea-turing concave-convex nonlinearities and a discontinuous right-hand side:{L(u)=H(u−μ)|u|^(p−2)u+λ|u|^(q−2)u,x∈Ω,u≥0,x∈Ω,u=0,x... This paper investigates the following mixed local and nonlocal elliptic problem fea-turing concave-convex nonlinearities and a discontinuous right-hand side:{L(u)=H(u−μ)|u|^(p−2)u+λ|u|^(q−2)u,x∈Ω,u≥0,x∈Ω,u=0,x∈R^(N)\Ω,where Ω ⊂R^(N)(N>2)is a bounded domain,μ≥0 and λ>0 are real parameters,H denotes the Heaviside function(H(t)=0 for t<0,H(t)=1 for t>0),and the mixed local and nolocal operator is defined as L(u)=−Δu+(−Δ)^(s)u with(−Δ)^(s) being the restricted fractional Laplace(0<s<1).The exponents satisfy 1<q<2<p.By employing a novel non-smooth variational principle,we establish the existence of an M-solution for this problem and identify a range for the exponent p. 展开更多
关键词 mixed local and nonlocal operator discontinuous non-smooth variational principle M-solution
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Strain localization and time-dependent deformation in granodiorite characterized by distributed optical fiber sensing
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作者 Shuting Miao Arno Zang +3 位作者 Guido Blöcher Yinlin Ji Hannes Hofmann Pengzhi Pan 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期166-178,共13页
A multi-stage stress relaxation test was performed on a granodiorite sample to understand the deformation process prior to the macroscopic failure of brittle rocks,as well as the transient response during stress relax... A multi-stage stress relaxation test was performed on a granodiorite sample to understand the deformation process prior to the macroscopic failure of brittle rocks,as well as the transient response during stress relaxation.Distributed optical fiber sensing was used to measure strains across the sample surface by helically wrapping the single-mode fiber around the cylindrical sample.Close agreement was observed between the circumferential strains obtained from the optical fibers and the extensometer.The reconstructed full-field strain contours show strain heterogeneity from the crack closure phase,and the strains in the later deformation phase are dominantly localized within the former high-strain zone.The Gini coefficient was used to quantify the degree of strain localization and shows an initial increase during the crack closure phase,a decrease during the linear elastic phase,and a subsequent increase during the post-yielding phase.This behavior corresponds to a process of initial localization from an imperfect boundary condition,homogenization,and eventual relocalization prior to the macroscopic failure of the sample.The transient strain rate decay during the stress relaxation phase was quantified using the p-value in the“Omori-like"power law function.A higher initial stress at the onset of relaxation results in a lower p-value,indicating a slower strain rate decay.As the sample approaches macroscopic failure,the lowest p-value shifts from the most damaged zone to adjacent areas,suggesting stress redistribution or crack propagation in deformed crystalline rocks under stress relaxation conditions. 展开更多
关键词 Distributed optical fiber sensing Stress relaxation Strain localization Time-dependent deformation
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Reconfigurable Intelligent Surface Aided Integrated Communication and Localization with a Single Access Point
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作者 Wang Xiyu Huang Yixuan +2 位作者 Yang Jie Han Yu Jin Shi 《China Communications》 2026年第1期218-233,共16页
Reconfigurable intelligent surfaces(RISs)not only assist communication but also help the localization of user equipment(UE).This study focuses on indoor localization of UE with a single access point(AP)and multiple RI... Reconfigurable intelligent surfaces(RISs)not only assist communication but also help the localization of user equipment(UE).This study focuses on indoor localization of UE with a single access point(AP)and multiple RISs.First,we propose a two-stage channel estimation scheme where RIS phase shifts are tuned to obtain multiple channel soundings.In the first stage,the newtonized orthogonal matching pursuit algorithm extracts the parameters of multiple paths from the received signals.Then,the LOS path and RISreflected paths are identified.In the second stage,the estimated path gains of RIS-reflected paths with different phase shifts are utilized to determine the angle of arrival(AOA)at the RIS by obtaining the angular pseudo spectrum.Consequently,by taking the AP and RISs as reference points,the linear least squares estimator can locate UE with the estimated AOAs.Simulation results show that the proposed algorithm can realize centimeter-level localization accuracy in the discussed scenarios.Moreover,the higher accuracy of pseudo spectrum,a larger number of channel soundings,and a larger number of reference points can realize higher localization accuracy of UE. 展开更多
关键词 channel estimation indoor localization linear least squares pseudo spectrum reconfigurable intelligent surface
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Bilateral Trade Gets a Boost:Financial institution initiative helps to facilitate trade opportunities for local businesses in Zimbabwe
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作者 PROBLEM MASAU 《ChinAfrica》 2026年第2期44-45,共2页
Stanbic Bank Zimbabwe is strategically positioning itself as a critical bridge for Zimbabwe’s local businesses,seeking to navigate the vast and complex Chinese market.
关键词 stanbic bank zimbabwe trade facilitation financial institution initiative bilateral trade Chinese market Zimbabwe local businesses
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Strategies and Policies for Developing Rural “Local Specialty Products” in Ecological Conservation Areas
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作者 Wei Houkai Hu Lingxiao 《Contemporary Social Sciences》 2026年第1期90-103,共14页
The promotion of rural revitalization within the ecological conservation areas(“ECAs”) requires a careful balance between ecological protection and economic development and should be guided by the principle of ecolo... The promotion of rural revitalization within the ecological conservation areas(“ECAs”) requires a careful balance between ecological protection and economic development and should be guided by the principle of ecological priority. The cultivation of rural “Local Specialty Products”(“LSPs”) under a green-development framework aligns with the functional positioning of these areas, drives the revitalization of rural industries, and constitutes a fundamental strategy for addressing the unique challenges they face. Although ECAs possess inherent advantages in terms of developing LSPs, they are also confronted by multiple constraints. Accordingly, we propose development objectives that emphasize(a) driving rural industrial prosperity,(b) enhancing the appeal of agricultural heritage, and(c) ensuring inclusive prosperity in the farming communities. In selecting pathways for growth, priority should be given to improving the quality of products, fostering distinctiveness of the technologies, nurturing cultural identities, and upholding the principle of common prosperity. From a policy standpoint, the development of rural LSPs should be recognized as a key lever for advancing the comprehensiveness of rural revitalization in the ECAs. We recommend a set of supportive measures—namely, reinforcing the guidance for spatial planning, integrating the consolidation of factor inputs, and ensuring the robustness of organizational guarantees—to facilitate the high-quality development of LSPs in these areas. 展开更多
关键词 ecological conservation areas areas rural local specialty products(LSPs) development objectives PATHWAYS policy support
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Statistical method for quantifying the strain localization process in Beishan granite under multi-creep triaxial compression based on distributed optical fiber sensing
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作者 Xiujun Zhang Peng-Zhi Pan Shuting Miao 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期398-415,共18页
To investigate the damage evolution caused by stress-driven and sub-critical crack propagation within the Beishan granite under multi-creep triaxial compressive conditions,the distributed optical fiber sensing and X-r... To investigate the damage evolution caused by stress-driven and sub-critical crack propagation within the Beishan granite under multi-creep triaxial compressive conditions,the distributed optical fiber sensing and X-ray computed tomography were combined to obtain the strain distribution over the sample surface and internal fractures of the samples.The Gini and skewness(G-S)coefficients were used to quantify strain localization during tests,where the Gini coefficient reflects the degree of clustering of elements with high strain values,i.e.,strain localization/delocalization.The strain localization-induced asymmetry of data distribution is quantified by the skewness coefficient.A precursor to granite failure is defined by the rapid and simultaneous increase of the G-S coefficients,which are calculated from strain increment,giving an earlier warning of failure by about 8%peak stress than those from absolute strain values.Moreover,the process of damage accumulation due to stress-driven crack propagation in Beishan granite is different at various confining pressures as the stress exceeds the crack initiation stress.Concretely,strain localization is continuous until brittle failure at higher confining pressure,while both strain localization and delocalization occur at lower confining pressure.Despite the different stress conditions,a similar statistical characteristic of strain localization during the creep stage is observed.The Gini coefficient increases,and the skewness coefficient decreases slightly as the creep stress is below 95%peak stress.When the accelerated strain localization begins,the Gini and skewness coefficients increase rapidly and simultaneously. 展开更多
关键词 Statistical method Multi-creep triaxial compression Strain localization quantification Distributed optical fiber sensing Precursor identification
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Highly stable lithium metal batteries enabled by nanometric anion aggregates reinforced solvation structure in locally concentrated ionic liquid electrolytes
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作者 Haifeng Tu Zhiyong Tang +16 位作者 Haiyang Zhang Zhicheng Wang Jiangyan Xue Shiqi Zhang Zheng Liu Yiwen Gao Peng Ding Yi Yang Guangye Wu Suwan Lu Lingwang Liu Guan Wu Qing Wang Byoungwoo Kang Jingjing Xu Hong Li Xiaodong Wu 《Journal of Energy Chemistry》 2026年第1期251-260,I0007,共11页
The practical application of lithium metal batteries(LMBs)requires electrolytes that simultaneously ensure high safety and interfacial stability.Although locally concentrated ionic liquid electrolytes(LCILEs)exhibit e... The practical application of lithium metal batteries(LMBs)requires electrolytes that simultaneously ensure high safety and interfacial stability.Although locally concentrated ionic liquid electrolytes(LCILEs)exhibit exceptional electrochemical stability and compatibility with electrode electrolyte interfaces(EEIs),two major challenges persist:(i)safety risks caused by excessive low-flash-point diluents,and(ii)insufficient understanding of how diluents modulate solvation structures.Herein,we introduce a low-diluent-content LCILE system composed of lithium bis(fluorosulfonyl)imide(LiFSI)salt,N-methyl-N-propyl-pyrrolidinium bis(fluorosulfonyl)imide(Pyr_(13)FSI)ionic liquid,and trifluoromethanesulfonate(TFS)diluent.The TFS diluent strengthens ion-ion interactions by lowering the dielectric constant of the electrolyte,resulting in the formation of a unique nanometric anion aggregates(N-AGGs)reinforced solvation structure.These large anionic clusters exhibit accelerated redox decomposition kinetics,facilitating the rapid formation of a thin,dense,and low-impedance EEI.Consequently,the Li/LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)coin cell achieves 87.8%capacity retention over 300 cycles at 4.3 V,while a practical 1.4 Ah Li/NCM622 pouch cell retains 84.5%capacity after 80 cycles at 4.5 V.Furthermore,the electrolyte demonstrates exceptional safety,and 2 Ah Li metal pouch cells successfully pass rigorous nail penetration tests without any ignition or explosion.This work not only provides a design strategy for intrinsically safe and high-performance electrolytes but also highlights the critical role of anion cluster decomposition kinetics in shaping EEI formation. 展开更多
关键词 Lithium metal batteries locally concentrated ionic liquid electrolytes Solvation structure Nanometric anion aggregates Redox decomposition kinetics
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Construction methods of nonlocal sets of orthogonal product states on multipartite quantum systems
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作者 Guang-Bao Xu Zhao-Xia Zhong +1 位作者 Yu-Guang Yang Dong-Huan Jiang 《Chinese Physics B》 2025年第11期309-316,共8页
Nonlocal set of orthogonal product states(OPSs)can improve the confidentiality of information when it is used to design quantum cryptographic protocols.It is a difficult question how to construct a nonlocal set of OPS... Nonlocal set of orthogonal product states(OPSs)can improve the confidentiality of information when it is used to design quantum cryptographic protocols.It is a difficult question how to construct a nonlocal set of OPSs on general multipartite and high dimensional quantum systems.Different from the previous works,we first present a novel method for constructing a nonlocal product set with 3d-2 members on C^(d)■C^(d)■C^(d)quantum system for d≥3.Then,we extend this construction method to C^(d_(1))■C^(d_(2))■C^(d_(3))quantum system and■_(i=1)^(n)C^(di)quantum system respectively,where 3≤d_(1)≤d_(2)≤d_(3)≤…≤dC_(d_(i))and n≥3.The nonlocal set of OPSs constructed by our method contains fewer elements than those constructed by the existing methods,except for one special case.More importantly,the set of states constructed by our method has a completely different structure from those constructed by the existing methods since our nonlocal set does not contain a“stopper”state.Our result is helpful to further understand the different structures of nonlocal sets on multipartite systems. 展开更多
关键词 nonlocal set local indistinguishability orthogonality-preserving measurement quantum nonlocality without entanglement
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LREGT:Local Relationship Enhanced Gated Transformer for Image Captioning
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作者 Yuting He Zetao Jiang 《Computers, Materials & Continua》 2025年第9期5487-5508,共22页
Existing Transformer-based image captioning models typically rely on the self-attention mechanism to capture long-range dependencies,which effectively extracts and leverages the global correlation of image features.Ho... Existing Transformer-based image captioning models typically rely on the self-attention mechanism to capture long-range dependencies,which effectively extracts and leverages the global correlation of image features.However,these models still face challenges in effectively capturing local associations.Moreover,since the encoder extracts global and local association features that focus on different semantic information,semantic noise may occur during the decoding stage.To address these issues,we propose the Local Relationship Enhanced Gated Transformer(LREGT).In the encoder part,we introduce the Local Relationship Enhanced Encoder(LREE),whose core component is the Local Relationship Enhanced Module(LREM).LREM consists of two novel designs:the Local Correlation Perception Module(LCPM)and the Local-Global Fusion Module(LGFM),which are beneficial for generating a comprehensive feature representation that integrates both global and local information.In the decoder part,we propose the Dual-level Multi-branch Gated Decoder(DMGD).It first creates multiple decoding branches to generate multi-perspective contextual feature representations.Subsequently,it employs the Dual-Level Gating Mechanism(DLGM)to model the multi-level relationships of these multi-perspective contextual features,enhancing their fine-grained semantics and intrinsic relationship representations.This ultimately leads to the generation of high-quality and semantically rich image captions.Experiments on the standard MSCOCO dataset demonstrate that LREGT achieves state-of-the-art performance,with a CIDEr score of 140.8 and BLEU-4 score of 41.3,significantly outperforming existing mainstream methods.These results highlight LREGT’s superiority in capturing complex visual relationships and resolving semantic noise during decoding. 展开更多
关键词 Image captioning local relation enhancement local correlation perception dual-level gating mechanism
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Indoor localization with channel state information images from selected multiple access points
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作者 LONG Liang WANG Xiaopeng +1 位作者 WANG Jiang LI Gang 《Journal of Measurement Science and Instrumentation》 2025年第4期569-577,共9页
To improve the accuracy of indoor localization methods with channel state information(CSI)images,a localization method that used CSI images from selected multiple access points(APs)was proposed.The method had an off-l... To improve the accuracy of indoor localization methods with channel state information(CSI)images,a localization method that used CSI images from selected multiple access points(APs)was proposed.The method had an off-line phase and an on-line phase.In the off-line phase,three APs were selected from the four APs in the localization area based on the received signal strength indication(RSSI).Next,CSI data was collected from the three selected APs using a commercial Intel 5300 network interface card.A single-channel subimage was constructed for each selected AP by combining the amplitude information from different antennas and the phase difference information between neighboring antennas.These sub-images were then merged to form a three-channel RGB image,which was subsequently fed into the convolutional neural network(CNN)for training.The CNN model was saved upon completion of training.In the on-line phase,the CSI data from the target device was collected,converted into images using the same process as in the off-line phase,and fed into the well-trained CNN model.Finally,the real position of the target device was estimated using a weighted centroid algorithm based on the model’s output probabilities.The proposed method was validated in indoor environments using two datasets,achieving good localization accuracy. 展开更多
关键词 WiFi indoor localization multiple access points channel state information image convolutional neural network(CNN) fingerprint localization weighted centroid algorithm
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The Efficacy of Whole-Course Local Simultaneous Integrated Boost Intensity-Modulated Radiotherapy in the Treatment of Locally Advanced Esophageal Cancer and Its Impact on Immune Function
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作者 Lei Yuan Yujuan Gao 《Journal of Clinical and Nursing Research》 2025年第3期224-230,共7页
Objective:To analyze the efficacy of whole-course local simultaneous integrated boost intensity-modulated radiotherapy(SIB-IMRT)on patients with locally advanced esophageal squamous cell carcinoma(ESCC).Methods:88 pat... Objective:To analyze the efficacy of whole-course local simultaneous integrated boost intensity-modulated radiotherapy(SIB-IMRT)on patients with locally advanced esophageal squamous cell carcinoma(ESCC).Methods:88 patients with ESCC admitted to the hospital between October 2022 and October 2024 were selected and randomly divided into two groups using a random number table.The experimental group received SIB-IMRT treatment,while the control group received conventional intensity-modulated radiotherapy(C-IMRT).The objective remission rate,immune function,tumor markers,and adverse reaction rate were compared between the two groups.Results:The objective remission rate in the experimental group was higher than that in the control group(P<0.05).Before treatment,there was no difference in immune function levels and tumor marker levels between the two groups(P>0.05).After treatment,the immune function levels in the experimental group were better than those in the control group,and the tumor marker levels were lower than those in the control group(P<0.05).The adverse reaction rate in the experimental group was lower than that in the control group(P<0.05).Conclusion:SIB-IMRT can improve the objective remission rate of patients with ESCC,protect their immune function,down-regulate tumor marker levels,and prevent side effects after treatment. 展开更多
关键词 Whole-course local simultaneous integrated boost intensity-modulated radiotherapy locally advanced esophageal squamous cell carcinoma EFFICACY Immune function
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Single-cell transcriptomic analysis identifies systemic immunosuppressive myeloid cells and local monocytes/macrophages as key regulators in polytrauma-induced immune dysregulation
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作者 Drishti Maniar MCole Keenum +6 位作者 Casey E.Vantucci Tyler Guyer Paramita Chatterjee Kelly Leguineche Kaitlyn Cheung Robert E.Guldberg Krishnendu Roy 《Bone Research》 2025年第5期1224-1238,共15页
Polytrauma with significant bone and volumetric muscle loss presents substantial clinical challenges.Although immune responses significantly influence fracture healing post-polytrauma,the cellular and molecular underp... Polytrauma with significant bone and volumetric muscle loss presents substantial clinical challenges.Although immune responses significantly influence fracture healing post-polytrauma,the cellular and molecular underpinnings of polytrauma-induced immune dysregulation require further investigation.While previous studies examined either injury site tissue or systemic tissue(peripheral blood),our study uniquely investigated both systemic and local immune cells at the same time to better understand polytrauma-induced immune dysregulation and associated impaired bone healing.Using single-cell RNA sequencing(scRNA-seq)in a rat polytrauma model,we analyzed blood,bone marrow,and the local defect soft tissue to identify potential cellular and molecular targets involved in immune dysregulation.We identified a trauma-associated immunosuppressive myeloid(TIM)cell population that drives systemic immune dysregulation,immunosuppression,and potentially impaired bone healing.We found CD1d as a global marker for TIM cells in polytrauma. 展开更多
关键词 bone volumetric muscle loss local monocytes macrophages injury site tissue polytrauma induced immune dysregulation systemic immunosuppressive myeloid cells systemic local immune cells systemic tissue peripheral blood our immune responses
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Rethinking the Causes of Local Government Debt
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作者 Congcong Yang 《Proceedings of Business and Economic Studies》 2025年第2期293-297,共5页
In recent years,local government debt reduction and risk prevention have been the subjects of common concern to all parties.China's local government debt has different reasons in different historical periods,and t... In recent years,local government debt reduction and risk prevention have been the subjects of common concern to all parties.China's local government debt has different reasons in different historical periods,and the main line running through this is the development orientation of local governments.It is undeniable that local government debt has played an indelible role in China's rapid economic growth.However,due to historical restrictions,flood irrigation inevitably brought sediment all over the ground.Therefore,this paper intends to rethink the causes of local government debt from the perspective of the dual role of regional government and the main body of meso economics. 展开更多
关键词 local government Promotion incentive Central-local relationship
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Crossover from weak antilocalization to weak localization behavior in Bi_(2)Te_(3)/MnTe bilayer films
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作者 Xu-Dong Shi Jian Gao +4 位作者 Ting-Ting Li Ming-Ze Li Xuan P.A.Gao Zhen-Hua Wang Zhi-Dong Zhang 《Rare Metals》 2025年第8期5643-5655,共13页
Electron-electron interactions(EEIs),quantum interference,and the effects of disorder on transport properties are essential topics in condensed matter physics.A series of our characterization work demonstrates that th... Electron-electron interactions(EEIs),quantum interference,and the effects of disorder on transport properties are essential topics in condensed matter physics.A series of our characterization work demonstrates that the morphology of Bi_(2)Te_(3)/MnTe bilayer film mainly depends on the magnetic substrate's growth mode and thickness.We propose that the temperature-dependent quantum interference of the electron wave function caused by disorder drives the transition from weak antilocalization(WAL) to weak localization(WL).Due to spin regulation,WL under low fields originates from the ferromagnetism in MnTe.The quantum interference effect(QIE) model analysis gives the degree of impurity scattering of the electron wave function.The electron wave is scattered by impurities,which causes the Berry phase to change from π to 0,producing a complete WL behavior.The stacked structure provides tunable degrees of freedom,allowing for independent optimization of topological properties and magnetic order through preferential growth orientation of topological insulator(TI) and magnetic layers,respectively. 展开更多
关键词 Bi_(2)Te_(3)/MnTe Quantum interference Weak antilocalization Weak localization
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关于Locale范畴反射子范畴的注解 被引量:1
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作者 孙向荣 贺伟 《数学年刊(A辑)》 CSCD 北大核心 2007年第6期821-826,共6页
利用Locale中的完全正则元和零维元构造性地给出了任意Locale的完全正则反射以及零维反射的描述,并且对于满足‘(?)’关系插入性的Locale,特别地,对正规Locale,证明了全体正则元构成的Locale是其正则反射.进而,利用平稳(flat)子Locale... 利用Locale中的完全正则元和零维元构造性地给出了任意Locale的完全正则反射以及零维反射的描述,并且对于满足‘(?)’关系插入性的Locale,特别地,对正规Locale,证明了全体正则元构成的Locale是其正则反射.进而,利用平稳(flat)子Locale的扩张引理给出了Locale的紧完全正则反射,紧零维反射以及紧正则反射的构造性描述. 展开更多
关键词 反射性 正则locale 完全正则locale 零维locale
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Analysis on Risk Influencing Factors of Local Urban Investment Bonds
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作者 XIANGZhengya LIUBaoquan 《外文科技期刊数据库(文摘版)经济管理》 2022年第3期031-034,共4页
Urban investment bonds are another financing method designed by local governments in China to avoid the legal restrictions of urban economic construction, especially urban infrastructure construction under specific ec... Urban investment bonds are another financing method designed by local governments in China to avoid the legal restrictions of urban economic construction, especially urban infrastructure construction under specific economic environment. Although the issuance of urban investment bonds has eased the financing difficulties of local governments to a certain extent, the credit risk of urban investment bonds has gradually emerged due to the rapid increase in the number of urban investment companies and the expansion of the debt scale. In the borrowing process, not only the local government has expanded the land finance, but also the financial transparency has decreased, which will affect the regional economic development level, the urbanization process and the financial and credit status of the city investment companies themselves. Therefore, first of all, the local government should promote the improvement of the tax system, reduce the government's reliance on land finance, actively enhance the government's financial transparency, reduce the information asymmetry between bond issuers and market investors, and reduce the debt risk. Secondly, for the sake of stable growth of local economy, over-investment and development of cities should be avoided. Finally, standardize enterprises to increase credit guarantee, avoid false credit guarantee, and improve the system of public disclosure of corporate financial risk information and the role of third-party market capital in strictly guarding the market, providing a more reliable capital guarantee for the issuance and operation of China's bond market. 展开更多
关键词 local city investment bonds investing in local government urban investment bonds investment bonds local debt investment risk local government investment behavior local city investment company
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弱空间式Locale
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作者 孙向荣 贺伟 《数学进展》 CSCD 北大核心 2007年第3期354-362,共9页
空间式locale范畴SLoc是locale范畴Loc的余反射满子范畴,但对locale乘积不封闭.本文引入弱空间式locale,证明弱空间式locale范畴WSloc为范畴Loc的余反射满子范畴,且对locale秉积封闭.还证明了一个locale A是空间式的当且仅当它的枝映... 空间式locale范畴SLoc是locale范畴Loc的余反射满子范畴,但对locale乘积不封闭.本文引入弱空间式locale,证明弱空间式locale范畴WSloc为范畴Loc的余反射满子范畴,且对locale秉积封闭.还证明了一个locale A是空间式的当且仅当它的枝映射localeN(A)是弱空间式的;一个空问式locale的每一个子locale都是空间式的当且仅当它的每一个子locale是弱空间式的.最后,证明了弱空间式性在定向函子下保持不变. 展开更多
关键词 弱空间式locale 空间式locale 核映射 伴随函子 无点子locale
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Local Rate of Convergence in the Functional Limit Theorem for Increments of a Fractional Brownian Motion 被引量:1
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作者 LIU Yonghong DING Ding ZHOU Xia 《数学进展》 北大核心 2025年第1期197-211,共15页
In this paper,we present local functional law of the iterated logarithm for Cs?rg?-Révész type increments of fractional Brownian motion.The results obtained extend works of Gantert[Ann.Probab.,1993,21(2):104... In this paper,we present local functional law of the iterated logarithm for Cs?rg?-Révész type increments of fractional Brownian motion.The results obtained extend works of Gantert[Ann.Probab.,1993,21(2):1045-1049]and Monrad and Rootzén[Probab.Theory Related Fields,1995,101(2):173-192]. 展开更多
关键词 fractional Brownian motion INCREMENT local functional law of the iterated logarithm large deviation small deviation
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Combined effects of local residual stresses,internal pores,and microstructures on the mechanical properties of laser-welded Ti-6Al-4V sheets 被引量:2
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作者 Wei Sun Haoyi Niu +5 位作者 Yiping Xia Kesong Miao Xingrui Jiang Min Chen Maulik Patel Guohua Fan 《Journal of Materials Science & Technology》 2025年第13期178-191,共14页
Laser-welded Ti-6Al-4 V is prone to severe residual stresses,microstructural variation,and structural de-fects which are known detrimental to the mechanical properties of weld joints.Residual stress removal is typical... Laser-welded Ti-6Al-4 V is prone to severe residual stresses,microstructural variation,and structural de-fects which are known detrimental to the mechanical properties of weld joints.Residual stress removal is typically applied to weld joints for engineering purposes via heat treatment,in order to avoid prema-ture failure and performance degradation.In the present work,we found that proper welding residual stresses in laser-welded Ti-6Al-4 V sheets can maintain better ductility during uniaxial tension,as op-posed to the stress-relieved counterparts.A detailed experimental investigation has been performed on the deformation behaviours of Ti-6Al-4 V butt welds,including residual stress distribution characteriza-tions by focused ion beam ring-coring coupled with digital image correlation(FIB-DIC),X-ray comput-erized tomography(CT)for internal voids,and in-situ DIC analysis of the subregional strain evolutions.It was found that the pores preferentially distributed near the fusion zone(FZ)boundary,where the compressive residual stress was up to-330 MPa.The removal of residual stress resulted in a changed failure initiation site from the base material to the FZ boundary,the former with ductile and the latter with brittle fracture characteristics under tensile deformation.The combined effects of residual stresses,microstructures,and internal pores on the mechanical responses are discussed in detail.This work high-lights the importance of inevitable residual stress and pores in laser weld pieces,leading to key insights for post-welding treatment and service performance evaluations. 展开更多
关键词 Residual stresses FIB-DIC Deformation behavior local strain Laser welding X-ray CT
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