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Electromagnetic Interpretation of Fractional-Order Elements
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作者 Guishu Liang Jiawei Hao Dongqing Shan 《Journal of Modern Physics》 2017年第14期2209-2218,共10页
Fractional circuits have attracted extensive attention of scholars and researchers for their superior performance and potential applications. Recently, the fundamentals of the conventional circuit theory were extended... Fractional circuits have attracted extensive attention of scholars and researchers for their superior performance and potential applications. Recently, the fundamentals of the conventional circuit theory were extended to include the new generalized elements and fractional-order elements. As is known to all, circuit theory is a limiting special case of electromagnetic field theory and the characterization of classical circuit elements can be given an elegant electromagnetic interpretation. In this paper, considering fractional-order time derivatives, an electromagnetic field interpretation of fractional-order elements: fractional-order inductor, fractional-order capacitor and fractional-order mutual inductor is presented, in terms of a quasi-static expansion of the fractional Maxwell’s equations. It shows that fractional-order elements can also be interpreted as a fractional electromagnetic system. As the element order equals to 1, the interpretation of fractional-order elements matches that of the classical circuit elements: L, C, and mutual inductor, respectively. 展开更多
关键词 FRACTIONAL CIRCUITS fractional-order elements Maxwell’s EQUATIONS ELECTROMAGNETIC Field
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Toward understanding the role of genomic repeat elements in neurodegenerative diseases 被引量:1
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作者 Zhengyu An Aidi Jiang Jingqi Chen 《Neural Regeneration Research》 SCIE CAS 2025年第3期646-659,共14页
Neurodegenerative diseases cause great medical and economic burdens for both patients and society;however, the complex molecular mechanisms thereof are not yet well understood. With the development of high-coverage se... Neurodegenerative diseases cause great medical and economic burdens for both patients and society;however, the complex molecular mechanisms thereof are not yet well understood. With the development of high-coverage sequencing technology, researchers have started to notice that genomic repeat regions, previously neglected in search of disease culprits, are active contributors to multiple neurodegenerative diseases. In this review, we describe the association between repeat element variants and multiple degenerative diseases through genome-wide association studies and targeted sequencing. We discuss the identification of disease-relevant repeat element variants, further powered by the advancement of long-read sequencing technologies and their related tools, and summarize recent findings in the molecular mechanisms of repeat element variants in brain degeneration, such as those causing transcriptional silencing or RNA-mediated gain of toxic function. Furthermore, we describe how in silico predictions using innovative computational models, such as deep learning language models, could enhance and accelerate our understanding of the functional impact of repeat element variants. Finally, we discuss future directions to advance current findings for a better understanding of neurodegenerative diseases and the clinical applications of genomic repeat elements. 展开更多
关键词 Alzheimer's disease ATAXIA deep learning long-read sequencing NEURODEGENERATION neurodegenerative diseases Parkinson's disease repeat element structural variant
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Attempt to generalize fractional-order electric elements to complex-order ones
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作者 司刚全 刁利杰 +2 位作者 朱建伟 雷妤航 张彦斌 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第6期87-92,共6页
The complex derivative D^α±jβ, with α, β ∈ R+ is a generalization of the concept of integer derivative, where α = 1,β = 0. Fractional-order electric elements and circuits are becoming more and more attrac... The complex derivative D^α±jβ, with α, β ∈ R+ is a generalization of the concept of integer derivative, where α = 1,β = 0. Fractional-order electric elements and circuits are becoming more and more attractive. In this paper, the complexorder electric elements concept is proposed for the first time, and the complex-order elements are modeled and analyzed.Some interesting phenomena are found that the real part of the order affects the phase of output signal, and the imaginary part affects the amplitude for both the complex-order capacitor and complex-order memristor. More interesting is that the complex-order capacitor can do well at the time of fitting electrochemistry impedance spectra. The complex-order memristor is also analyzed. The area inside the hysteresis loops increases with the increasing of the imaginary part of the order and decreases with the increasing of the real part. Some complex case of complex-order memristors hysteresis loops are analyzed at last, whose loop has touching points beyond the origin of the coordinate system. 展开更多
关键词 complex derivative fractional-order elements imaginary and real part MEMRISTOR
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Creep constitutive model for damaged soft rock based on fractional-order nonlinear theory 被引量:1
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作者 BAO Min ZHOU Zihan +1 位作者 CHEN Zhonghui ZHANG Lingfei 《Journal of Mountain Science》 2025年第6期2276-2290,共15页
Investigating the combined effects of mining damage and creep damage on slope stability is crucial,as it can comprehensively reveal the non-linear deformation characteristics of rock under their joint influence.This s... Investigating the combined effects of mining damage and creep damage on slope stability is crucial,as it can comprehensively reveal the non-linear deformation characteristics of rock under their joint influence.This study develops a fractional-order nonlinear creep constitutive model that incorporates the double damage effect and implements a non-linear creep subroutine for soft rock using the threedimensional finite difference method on the FLAC3D platform.Comparative analysis of the theoretical,numerical,and experimental results reveals that the fractional-order constitutive model,which incorporates the double damage effect,accurately reflects the distinct deformation stages of green mudstone during creep failure and effectively captures the non-linear deformation in the accelerated creep phase.The numerical results show a fitting accuracy exceeding 97%with the creep test curves,significantly outperforming the 61%accuracy of traditional creep models. 展开更多
关键词 Mining damage Creep damage fractional-order Constitutive model Secondary development
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Size-dependent bending and vibration analysis of piezoelectric nanobeam based on fractional-order kinematic relations
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作者 Zhiwen FAN Hai QING 《Applied Mathematics and Mechanics(English Edition)》 2025年第7期1261-1272,I0003-I0011,共21页
In this paper,a fractional-order kinematic model is utilized to capture the size-dependent static bending and free vibration responses of piezoelectric nanobeams.The general nonlocal strains in the Euler-Bernoulli pie... In this paper,a fractional-order kinematic model is utilized to capture the size-dependent static bending and free vibration responses of piezoelectric nanobeams.The general nonlocal strains in the Euler-Bernoulli piezoelectric beam are defined by a frame-invariant and dimensionally consistent Riesz-Caputo fractional-order derivatives.The strain energy,the work done by external loads,and the kinetic energy based on the fractional-order kinematic model are derived and expressed in explicit forms.The boundary conditions for the nonlocal Euler-Bernoulli beam are derived through variational principles.Furthermore,a finite element model for the fractional-order system is developed in order to obtain the numerical solutions to the integro-differential equations.The effects of the fractional order and the vibration order on the static bending and vibration responses of the Euler-Bernoulli piezoelectric beams are investigated numerically.The results from the present model are validated against the existing results in the literature,and it is demonstrated that they are theoretically consistent.Although this fractional finite element method(FEM)is presented in the context of a one-dimensional(1D)beam,it can be extended to higher dimensional fractional-order boundary value problems. 展开更多
关键词 scale effect Riesz-Caputo fractional-order derivative Euler-Bernoulli piezoelectric beam fractional-order¯nite element method(FEM)
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High-efficiency RGB achromatic liquid crystal diffractive optical elements 被引量:1
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作者 Yuqiang Ding Xiaojin Huang +2 位作者 Yongziyan Ma Yan Li Shin-Tson Wu 《Opto-Electronic Advances》 2025年第3期4-15,共12页
Liquid crystal Pacharatnam-Berry phase optical elements(PBOEs)have found promising applications in augmented reality and virtual reality because of their slim formfactor,lightweight,and high optical efficiency.However... Liquid crystal Pacharatnam-Berry phase optical elements(PBOEs)have found promising applications in augmented reality and virtual reality because of their slim formfactor,lightweight,and high optical efficiency.However,chromatic aberration remains a serious longstanding problem for diffractive optics,hindering their broader adoption.To overcome the chromatic aberrations for red,green and blue(RGB)light sources,in this paper,we propose a counterintuitive multi-twist structure to achieve narrowband PBOEs without crosstalk,which plays a vital role to eliminate the chromatic aberration.The performance of our designed and fabricated narrowband Pacharatnam-Berry lenses(PBLs)aligns well with our simulation results.Furthermore,in a feasibility demonstration experiment using a laser projector,our proposed PBL system indeed exhibits a diminished chromatic aberration as compared to a broadband PBL.Additionally,polarization raytracing is implemented to demonstrate the versatility of the multi-twist structure for designing any RGB wavelengths with high contrast ratios.This analysis explores the feasibility of using RGB laser lines and quantum dot light-emitting diodes.Overall,our approach enables high optical efficiency,low fabrication complexity,and high degree of design freedom to accommodate any liquid crystal material and RGB light sources,holding immense potential for widespread applications of achromatic PBOEs. 展开更多
关键词 achromatic diffractive optical elements Pacharatnam-Berry phase optical elements liquid crystal planar optics near-eye displays
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Challenges to and Countermeasures for the Value Realization of Healthcare Data Elements in China 被引量:1
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作者 Tianan Yang Wenhao Deng +3 位作者 Ran Liu Tianyu Wang Yuanyuan Dai Jianwei Deng 《Health Care Science》 2025年第3期225-228,共4页
As a new type of production factor in healthcare,healthcare data elements have been rapidly integrated into various health production processes,such as clinical assistance,health management,biological testing,and oper... As a new type of production factor in healthcare,healthcare data elements have been rapidly integrated into various health production processes,such as clinical assistance,health management,biological testing,and operation and supervision[1,2].Healthcare data elements include biolog.ical and clinical data that are related to disease,environ-mental health data that are associated with life,and operational and healthcare management data that are related to healthcare activities(Figure 1).Activities such as the construction of a data value assessment system,the devel-opment of a data circulation and sharing platform,and the authorization of data compliance and operation products support the strong growth momentum of the market for health care data elements in China[3]. 展开更多
关键词 China healthcare data elements healthcare data management value realization
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ON POTENT ELEMENTS AND PSEUDO CLEAN RINGS
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作者 DING Yan GAO Han-peng +2 位作者 LIU Xin-yi YAN Zi-yi ZHANG Ting 《数学杂志》 2025年第1期39-47,共9页
In this paper,potent index of an element and pseudo clean rings are considered.Some properties and examples of pseudo clean rings are given.We also show that Zm is pseudo clean for every 2≤m∈Z and pseudo clean rings... In this paper,potent index of an element and pseudo clean rings are considered.Some properties and examples of pseudo clean rings are given.We also show that Zm is pseudo clean for every 2≤m∈Z and pseudo clean rings are clean.Furthermore,we prove pseudo clean rings are directly finite and have stable range one. 展开更多
关键词 clean rings strongly J-clean rings pseudo clean rings potent elements
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Elements gradient doping in Mn-based Li-rich layered oxides for long-life lithium-ion batteries 被引量:2
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作者 Yinzhong Wang Shiqi Liu +7 位作者 Xianwei Guo Boya Wang Qinghua Zhang Yuqiang Li Yulong Wang Guoqing Wang Lin Gu Haijun Yu 《Journal of Materials Science & Technology》 2025年第4期266-273,共8页
The cobalt-free Mn-based Li-rich layered oxide material has the advantages of low cost,high energy density,and good performance at low temperatures,and is the promising choice for energy storage batteries.However,the ... The cobalt-free Mn-based Li-rich layered oxide material has the advantages of low cost,high energy density,and good performance at low temperatures,and is the promising choice for energy storage batteries.However,the long-cycling stability of batteries needs to be improved.Herein,the Mn-based Li-rich cathode materials with small amounts of Li2 MnO3 crystal domains and gradient doping of Al and Ti elements from the surface to the bulk have been developed to improve the structure and interface stability.Then the batteries with a high energy density of 600 Wh kg^(-1),excellent capacity retention of 99.7%with low voltage decay of 0.03 mV cycle^(-1) after 800 cycles,and good rates performances can be achieved.Therefore,the structure and cycling stability of low voltage Mn-based Li-rich cathode materials can be significantly improved by the bulk structure design and interface regulation,and this work has paved the way for developing low-cost and high-energy Mn-based energy storage batteries with long lifetime. 展开更多
关键词 Mn-based Li-rich layered oxide cathode Li_(2)MnO_(3)crystal domain elemental gradient Lithium-ion batteries Energy storage
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Construction of anticorrosive superhydrophobic coatings on B10 copper–nickel alloy welded joints and influence of construction elements on their properties 被引量:1
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作者 Xin-wei Zhang Yan Zhao +6 位作者 Xiao-hui Dou Zong-hao He Hong-xi Jin Chuan He Song-nan Zhao Fu-fang Han Da-lei Zhang 《Journal of Iron and Steel Research International》 2025年第9期2982-2994,共13页
Cu–Ni and Cu–Co–Ni superhydrophobic films were constructed on the surface of B10 copper–nickel alloy welded joints using a two-step process of electrodeposition and stearic acid modification.The chemical compositi... Cu–Ni and Cu–Co–Ni superhydrophobic films were constructed on the surface of B10 copper–nickel alloy welded joints using a two-step process of electrodeposition and stearic acid modification.The chemical composition of the film surface was determined using surface characterization techniques.The corrosion resistance of the films was characterized using electrochemical impedance spectroscopy,potentiodynamic polarization,and scanning Kelvin probe microscopy at multiple scales.The thermal stability,mechanical stability,and self-cleaning properties of the films were also characterized.It was determined that the Cu–Co–Ni superhydrophobic film exhibited the best performance,with a static water contact angle of 159.3°,a roll-off angle of 2.3°,a charge transfer resistance 3300 times higher than the substrate,a self-corrosion current density nearly three orders of magnitude lower,and a surface Kelvin potential increase of 420 mV.The film demonstrated good thermal stability,excellent mechanical stability,and outstanding self-cleaning properties.Combining with previous studies,it was found that Co elements in the film contribute to the formation of a uniform and dense film,Ni elements enhance the adhesion and corrosion resistance between the films,and the combination of Co and Ni elements promotes uniform surface potential and further improves the corrosion resistance and interfilm adhesion of the films. 展开更多
关键词 Material failure and protection Superhydrophobic film B10 copper-nickel alloy welded joint Corrosion resistance Deposition element effect
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Determination of Organic Matter and Trace Metals Elements (As, Sb, Cd, Hg, Ni, Pb, Cr, Zn) in the Soils of the Banks of Watercourses in Brazzaville City (Republic of Congo)
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作者 Mbianda Nfong-Ya Orline Lesley Nzila Jean de Dieu +5 位作者 Louzayadio Mvouezolo Raison Félicien Bonazaba Milandou Longin Justin Clair Nguelet-Moukaha Isidore Wando Georgy Patience Ouamba Jean Maurille Aina Martin Pépin 《Open Journal of Soil Science》 2025年第2期156-172,共17页
This work focused on determining the physico-chemical characteristics (pH, carbon and nitrogen) and trace metal elements (TMEs) content (As, Sb, Cd, Hg, Ni, Pb, Cr, Zn) of soils in the Brazzaville city. Soil samples w... This work focused on determining the physico-chemical characteristics (pH, carbon and nitrogen) and trace metal elements (TMEs) content (As, Sb, Cd, Hg, Ni, Pb, Cr, Zn) of soils in the Brazzaville city. Soil samples were taken from a depth of 0 to 20 cm using a hand auger on both banks of five tributaries of the Congo River (Djoué, Mfilou, Mfoa, Tsiémé, Djiri) that flow through the city of Brazzaville. 90 sampling points were defined, with 3 points 250 m apart on the banks and located, for each river, at three sites: upstream, midstream and downstream. Finally, 15 composite samples representative of the study area were taken. The average pH values of the water varied between 6.5 and 7.5. These pH values show that the soils studied are neutral. Total carbon content varied between 0.7% (Djiri) and 1.6% (Djoué). Total nitrogen content ranged from 0.08% (Djiri) to 0.12% (Djoué). TMEs contents varied from 0.5 to 1.8 mg/kg for Sb, from 0.5 to 2.5 mg/kg for As, from 0.1 to 0.18 mg/kg for Cd, from 4.2 to 11.3 mg/kg for Cr, from 0.07 to 0.27 mg/kg for Hg, from 0.7 to 2.4 mg/kg for Ni, from 0 to 158 mg/kg for Pb and from 16 to 105 mg/kg for Zn. The lowest TMEs levels were observed in the soils of the Djiri river, while the highest levels were observed in the soils of the Djoué and Tsiémé rivers. The ANOVA and Bonferroni test did not show significant differences in the means of the parameters measured (p > 0.05). The TMEs levels were below the accepted standards (NF U44-041), with the exception of Pb, which had high levels downstream of the Djoué. According to the pollution index values calculated using soil TME content, the soils on the banks of the Djoué river are considered polluted, while those on the banks of the Tsiémé river are moderately polluted, those on the banks of the Mfoa and Mfilou rivers are slightly polluted, and the soils on the banks of Djiri river are unpolluted. 展开更多
关键词 Carbon Nitrogen Trace Metal elements Soil BRAZZAVILLE CONGO
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Effects of potential field delay and coupling delay on collective behavior of a fractional-order coupled system in a dichotomous fluctuating potential
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作者 Yangfan Zhong Xi Chen +1 位作者 Maokang Luo Tao Yu 《Chinese Physics B》 2025年第5期270-287,共18页
The collective dynamic of a fractional-order globally coupled system with time delays and fluctuating frequency is investigated.The power-law memory of the system is characterized using the Caputo fractional derivativ... The collective dynamic of a fractional-order globally coupled system with time delays and fluctuating frequency is investigated.The power-law memory of the system is characterized using the Caputo fractional derivative operator.Additionally,time delays in the potential field force and coupling force transmission are both considered.Firstly,based on the delay decoupling formula,combined with statistical mean method and the fractional-order Shapiro–Loginov formula,the“statistic synchronization”among particles is obtained,revealing the statistical equivalence between the mean field behavior of the system and the behavior of individual particles.Due to the existence of the coupling delay,the impact of the coupling force on synchronization exhibits non-monotonic,which is different from the previous monotonic effects.Then,two kinds of theoretical expression of output amplitude gains G and G are derived by time-delay decoupling formula and small delay approximation theorem,respectively.Compared to G,G is an exact theoretical solution,which means that G is not only more accurate in the region of small delay,but also applies to the region of large delay.Finally,the study of the output amplitude gain G and its resonance behavior are explored.Due to the presence of the potential field delay,a new resonance phenomenon termed“periodic resonance”is discovered,which arises from the periodic matching between the potential field delay and the driving frequency.This resonance phenomenon is analyzed qualitatively and quantitatively,uncovering undiscovered characteristics in previous studies. 展开更多
关键词 potential field delay coupling delay fractional-order collective behavior
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The enrichment of hazardous elements, rare earth elements and other inorganic constituents in a thick coal seam of the Lower Indus Basin, Pakistan
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作者 Hassan Nasir Mangi Liqiang Ma +4 位作者 Robert B.Finkelman Detian Yan Jing Li Lara Sindhu Umar Ashraf 《International Journal of Coal Science & Technology》 2025年第3期291-312,共22页
The presence of inorganic constituents in coal is controlled by different geological factors,which,in turn,affect the technological,environmental,and health impacts of the coal.The main aim of this study is to objecti... The presence of inorganic constituents in coal is controlled by different geological factors,which,in turn,affect the technological,environmental,and health impacts of the coal.The main aim of this study is to objectively assess the mineralogical and geochemical characteristics of a thickest low-rank coal seam in the Lower Indus Basin southeastern Pakistan,and further investigate different controlling factors.The analytical results of major oxides,trace elements,and rare earth elements revealed that the weathering conditions were progressively variable and moderate.The sediment source,mainly of felsic and intermediate composition,was dominated by granitic rocks.The geochemical assessment reveals different depositional factors like marine environment influenced,while transitional and freshwater sediments influenced the center of the coal peat mire.Strontium,Zinc,and several hazardous trace elements,including Cu,Ni,Cr,and Co,have higher concentrations in these coals compared to world low-rank,U.S.,and Chinese coals.The relatively higher concentration of Sr in the thick coal seam in the Lower Indus Basin,compared to other coals seams in Pakistan and the enrichment of Sr was primarily controlled by the denudation of crystalline rocks and marine influx in the coal-basin.The REY distribution pattern showed that enrichment of medium and heavy rare earth elements is higher than light rare earth elements in the coal seam.The Gd distribution pattern in the coal seam demonstrated that strong positive anomalies had a good affinity with paleo-acidic water concentration in the study area.The higher concentration of Sr and other elements enables a better assessment understanding of the coal geochemical history. 展开更多
关键词 Coal geochemical analysis Trace elements STRONTIUM Hazardous elements Rare earth elements Lower-Indus Basin
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A Hybrid Machine Learning and Fractional-Order Dynamical Framework for Multi-Scale Prediction of Breast Cancer Progression
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作者 David Amilo Khadijeh Sadri +1 位作者 Evren Hincal Mohamed Hafez 《Computer Modeling in Engineering & Sciences》 2025年第11期2189-2222,共34页
Breast cancer’s heterogeneous progression demands innovative tools for accurate prediction.We present a hybrid framework that integrates machine learning(ML)and fractional-order dynamics to predict tumor growth acros... Breast cancer’s heterogeneous progression demands innovative tools for accurate prediction.We present a hybrid framework that integrates machine learning(ML)and fractional-order dynamics to predict tumor growth across diagnostic and temporal scales.On the Wisconsin Diagnostic Breast Cancer dataset,seven ML algorithms were evaluated,with deep neural networks(DNNs)achieving the highest accuracy(97.72%).Key morphological features(area,radius,texture,and concavity)were identified as top malignancy predictors,aligning with clinical intuition.Beyond static classification,we developed a fractional-order dynamical model using Caputo derivatives to capture memory-driven tumor progression.The model revealed clinically interpretable patterns:lower fractional orders correlated with prolonged aggressive growth,while higher orders indicated rapid stabilization,mimicking indolent subtypes.Theoretical analyses were rigorously proven,and numerical simulations closely fit clinical data.The framework’s clinical utility is demonstrated through an interactive graphics user interface(GUI)that integrates real-time risk assessment with growth trajectory simulations. 展开更多
关键词 Machine learning fractional-order breast cancer physiological dynamics maternal health preventable deaths
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Traditional and Contemporary Elements INJECTING NEW ENERGY INTO XIZANG'S FASHION INDUSTRY
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作者 Degyi Chodron(Text/Photos) Li Xiaosu(Translated) 《China's Tibet》 2025年第2期36-38,共3页
Under the starry night,a fashion extravaganza was staged in Lhasa.The Fashion Night is a local fashion show in Xizang combining tradition and innovation as well as modernity and international flavor.By providing them ... Under the starry night,a fashion extravaganza was staged in Lhasa.The Fashion Night is a local fashion show in Xizang combining tradition and innovation as well as modernity and international flavor.By providing them with opportunities to present their art works to more audiences,it built a platform for young Tibetan designers for their careers to take root and blossom on the plateau.It is also aimed to bring more people to pay attention to the fashion culture of Xizang,and infuse new vitality into the development of local fashion industry. 展开更多
关键词 traditional elements modernity international flavor local fashion show fashion night contemporary elements Xizang fashion industry tradition innovation fashion show
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Data Elements Accumulation Enabling the“Threeizations”Upgrading of Manufacturing:Theoretical Mechanism
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作者 Hao Xie 《Proceedings of Business and Economic Studies》 2025年第2期298-304,共7页
The data production elements are driving profound transformations in the real economy across production objects,methods,and tools,generating significant economic effects such as industrial structure upgrading.This pap... The data production elements are driving profound transformations in the real economy across production objects,methods,and tools,generating significant economic effects such as industrial structure upgrading.This paper aims to reveal the impact mechanism of the data elements on the“three transformations”(high-end,intelligent,and green)in the manufacturing sector,theoretically elucidating the intrinsic mechanisms by which the data elements influence these transformations.The study finds that the data elements significantly enhance the high-end,intelligent,and green levels of China's manufacturing industry.In terms of the pathways of impact,the data elements primarily influence the development of high-tech industries and overall green technological innovation,thereby affecting the high-end,intelligent,and green transformation of the industry. 展开更多
关键词 Data elements MANUFACTURING HIGH-END INTELLIGENT Green
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Geochemical characteristics of rare earth elements in sediments of the Qiongdongnan Basin and their sedimentological implications
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作者 Ke Wang 《Episodes》 2025年第1期81-93,共13页
In this paper,core samples from the Well LS33 in the deep-water area of the Qiongdongnan Basin(QDNB)in the South China Sea were selected and analyzed by group(authigenic carbonate and terrigenous detritus)to obtain th... In this paper,core samples from the Well LS33 in the deep-water area of the Qiongdongnan Basin(QDNB)in the South China Sea were selected and analyzed by group(authigenic carbonate and terrigenous detritus)to obtain the contents of rare earth elements(REE)to explore the degree of preservation of paleo-seawater information by carbonate components and elucidate the provenance relationship between the QDNB and the Yinggehai Basin and the provenance changes in the deep-water area of the QDNB since the Oligocene.The main achievements of this paper are as follows:(1)In the process of extracting the autogenic carbonate,the iron-manganese oxide envelope on the surface of the sediment particles(which can adsorb REE or its complexes in seawater)will partially dissolve into the autogenic carbonate components,thus covering the REE geochem-ical information of paleo-seawater carried by the auto-genic carbonate.Therefore,caution should be exercised when using the geochemical characteristics of REE in the carbonate component of impure carbonate rocks to reflect the sedimentary paleoenvironment.(2)The analysis of the REE geochemical characteristics of multiple cores in the Ying-gehai-QDNB shows that there is a close provenance rela-tionship between the two Basins.The sediments in the central depression area of the Yinggehai Basin and the deep-water area in the western part of the QDNB generally contain more feldspar(Eu-rich)minerals.Since the Eocene,paleo-rivers have carried ultramafic-mafic materials originating from the western South China Sea into the sea.Affected by the transport distance and sea level changes,the content of feldspar(Eu-rich)minerals in the sediments of the QDNB from west to east gradually decreased. 展开更多
关键词 SEDIMENTS carbonate components rare earth elements ree qiongdongnan basin qdnb geochemical characteristics rare earth elements Qiongdongnan Basin terrigenous detritus
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Role of IVA elements in magnetism and corrosion of FeBC glasses
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作者 Yan-Xu Li Yu Feng +9 位作者 Xin-Long Lu Zhao-Xuan Wang Qi Chen Zhi-Gang Qi Zi-Qi Song Zheng Wang Shao-Peng Pan Jing Pang Ki-Buem Kim Wei-Min Wang 《Rare Metals》 2025年第10期7784-7796,共13页
The microstructure,soft magnetic properties and corrosion resistance of Fe_(83)B_(9)C_(6)X_(2)(X=C,Si,Ge,Sn;i.e.,IVA elements)amorphous alloys were systematically investigated.As the atomic mass of the IVA elements(M_... The microstructure,soft magnetic properties and corrosion resistance of Fe_(83)B_(9)C_(6)X_(2)(X=C,Si,Ge,Sn;i.e.,IVA elements)amorphous alloys were systematically investigated.As the atomic mass of the IVA elements(M_(IVA))increased,the saturation magnetization(B_(s))and gyromagnetic ratio(γ)followed a non-monotonic trend.They first increased and then decreased,showing an inverse correlation with the change in their inter-atomic characteristic distance(δ_(c)).The highest B_(s)(1.76 T)and y were observed with a minor addition of Ge.Simultaneously,the corrosion potential(E_(corr)),wetting angle(θ_(w)),permeability(μ),and relaxation rate(ω_(r))initially decreased and then increased.Si addition led to the lowest corrosion resistance,the smallest permeability,and the highest coercivity(H_(c)).This is due to precipitated crystallites and induced structural heterogeneity.Electron paramagnetic resonance(EPR)analysis revealed that Ge doping enhanced structural homogeneity and cluster alignment,contributing to its superior soft magnetic performance.These findings are conducive to developing new low-cost Fe-based amorphous alloys with excellent soft magnetic properties. 展开更多
关键词 Fe-based glasses MAGNETIZATION IVA elements
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Selective recovery of rare earth elements by smelting of magnets
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作者 Venkata Lakshmi Borra Prasanta Jana +3 位作者 PPSahoo Prakash Venkatesan Mehmet Ali Recai Onal Chenna Rao Borra 《Journal of Rare Earths》 2025年第1期209-217,I0008,共10页
Rare earth elements(REEs)play a crucial role in many technologies from daily appliances in cell phones to more advanced wind turbines and electric cars.Permanent magnets account for a quarter of total global REEs prod... Rare earth elements(REEs)play a crucial role in many technologies from daily appliances in cell phones to more advanced wind turbines and electric cars.Permanent magnets account for a quarter of total global REEs production and have high recycling value.In this study,smelting process was used to selectively oxidize REEs in the permanent magnets by adding Fe_(2)O_(3).This separates REEs into a slag phase from an iron-rich metallic phase.B_(2)O_(3) was also added to the system as a flux to lower the slag melting temperature.This minimizes REEs loss to the metallic phase and allows a more efficient phase separation.The effect of flux and oxidizing agent addition was investigated on both regular and cerium-rich NdFeB(NdCeFeB)magnets.At 1350℃and for 1 h,the slag phase was successfully separated from the metallic phase with the addition of 0.8 stoichiometric amount of Fe_(2)O_(3) and 40 wt%of B_(2)O_(3).Scanning electron microscopy-energy dispersive X-ray spectroscopy(SEM-EDX)analysis reveals that REEs in the magnet do not migrate to the metal phase while the REE-rich slag phase contains almost no iron.After the selective removal of iron into the metallic phase,REEs are recovered from the slag phase through an acid leaching process allowing>99%of REEs recovery.Boron in the magnet can also be recovered as useful boric acid by evaporation and crystallisation technique.The proposed process in this study is reagent and energy-efficient with almost complete valorisation of both NdCeFeB and NdFeB magnets. 展开更多
关键词 RECYCLING Rare earth elements NdFeBmagnets SMELTING LEACHING
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A comprehensive review on rare earth elements:resources,technologies,applications,and prospects
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作者 Tian-Yu Zhao Wei-Lun Li +6 位作者 Sadan Kelebek Yeonuk Choi Cheng-Qian Wu Wen-Juan Zhang Chen-Yang Wang Zhong-Wei Zhao Farzaneh Sadri 《Rare Metals》 2025年第10期7011-7040,共30页
Rare earth elements(REEs),with their unique magnetic,optical,and electrical properties,have become indispensable strategic resources.Widely applied in critical fields such as aviation,telecommunications,electronics,en... Rare earth elements(REEs),with their unique magnetic,optical,and electrical properties,have become indispensable strategic resources.Widely applied in critical fields such as aviation,telecommunications,electronics,energy,transportation,and medicine,REEs play a vital role in advancing technology and driving social and economic development.However,the REE industry faces numerous challenges,including unbalanced resource distribution,supply and demand imbalances,international competition,technological limitations,and associated environmental pollution.This paper,incorporating both the historical evolution and current state of the REE industry,provides a comprehensive examination of the chemistry,applications,resources,technologies,challenges,and prospects of REEs.Specifically,it analyzes China's REE industry,which holds the largest global reserves and production capacity.As a key feature,this paper introduces the Tai Chi model for sustainable development in the REE industry,offering an in-depth analysis of two primary approaches—mining and recycling;the four critical participants—governments,enterprises,researchers,and consumers;and the eight essential influencing factors—resources,energy,environment,policy,applications,technology,supply and demand,and economy.The Tai Chi model not only clarifies the responsibilities and significance of each individual but also highlights their interconnectedness,providing a compelling framework for envisioning the sustainable development of the REE industry.Moreover,the paper identifies the major challenges currently facing the industry and offers insights into the future development of REEs.As such,this work contributes to a deeper understanding of the multifaceted REE landscape and underscores the importance of sustainable practices to ensure REEs'lasting positive impact on the global industry. 展开更多
关键词 Rare earth elements RESOURCE Technology Mining RECYCLING Sustainability
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