In the annals of Indian literature and spirituality,few figures resonate as profoundly as Surdas,a 16th-century poet-saint whose works have transcended time and cultural boundaries.While he is primarily celebrated for...In the annals of Indian literature and spirituality,few figures resonate as profoundly as Surdas,a 16th-century poet-saint whose works have transcended time and cultural boundaries.While he is primarily celebrated for his devotional hymns dedicated to Lord Krishna,a deeper exploration of his writings reveals a profound understanding of child psychology.Surdas,through his poetic lens,captures the essence of childhood,fostering a nuanced comprehension of the emotional and psychological landscape of children.This essay delves into the theme of Surdas as a master of child psychology,examining how his insights into the innocence,curiosity,and emotionality of children can be perceived as an early exploration of child development.At the heart of Surdas's poetry is a celebration of innocence,a quality that defines childhood.His verses often depict the playful antics of Krishna as a child,embodying the joy,spontaneity,and purity that characterize early life untouched by the burdens and complexities of adulthood.In his portrayal of Krishna’s mischievous Surdas encapsulates the essence of childlike wonder.In modern child psychology,curiosity is recognized as a vital element in learning and development.Surdas’s emphasis on the playful exploration of the world resonates with contemporary theories that advocate for experiential learning.By portraying Krishna as an inquisitive child,Surdas implicitly encourages adults to cultivate environments where children feel safe to ask questions,experiment,and engage with their surroundings.The paper is an earnest attempt to explain the key concepts of child psychology as perceived in the poetry of Surdas sagar saar.展开更多
The Editorial Office of Water Science and Engineering would like to express their sincere appreciation to the following peer reviewers for their devotion of time and energy to the journal in the year 2025.
ABOUT THIS JOURNAL.Launched in 1988,the Chinese Journal of Chemical Physics(CJCP)is devoted to reporting new and original experimental and theoret-ical research on interdisciplinary areas,with chemistry and physics gr...ABOUT THIS JOURNAL.Launched in 1988,the Chinese Journal of Chemical Physics(CJCP)is devoted to reporting new and original experimental and theoret-ical research on interdisciplinary areas,with chemistry and physics groundwork of interest to r resear chers,faculty and students domestic and abroad in the fields of chemistry,physics,material and biological sciences and their interdisciplinary areas.展开更多
Chinese Journal of Notural Mdicines(CINM,ISSN 2095-6975,original ISSN 1672-3651)was founded in May 2003 and is sponsored by China Pharmaceutical University and Chinese Phar-maccutical Association.The printed version o...Chinese Journal of Notural Mdicines(CINM,ISSN 2095-6975,original ISSN 1672-3651)was founded in May 2003 and is sponsored by China Pharmaceutical University and Chinese Phar-maccutical Association.The printed version of CINM is published monthly by Science Press and is web edition is published by Elsevier.CJNM is devoted to communications among pharmaccutical and medicinal plant scientists who are interested in the advance-ment of the botanical,chemical,and biological sciences related to natural medicines,ineluding traditional Chinese medicines(TCM).展开更多
Aim&Scope:Journal of Mountain Science (JMS) is devoted to mountains and their surrounding lowlands-ecoregions of particular global importance,with a particular emphasis on the important highlands/mountains in the ...Aim&Scope:Journal of Mountain Science (JMS) is devoted to mountains and their surrounding lowlands-ecoregions of particular global importance,with a particular emphasis on the important highlands/mountains in the world.JMS mainly publishes academic and technical papers concerning environmental changes and sustainable development in mountain areas under natural conditions or/and with the influence of human activities.It also accepts book reviews,commentary,and reports on mountain research and introductions to mountain research organizations.展开更多
Deep Underground Science and Engineering (DUSE) is a new international journal (Online ISSN:2770-1328;Print ISSN:2097-0668) launched by China University of Mining and Technology.The Journal is managed by a renowned in...Deep Underground Science and Engineering (DUSE) is a new international journal (Online ISSN:2770-1328;Print ISSN:2097-0668) launched by China University of Mining and Technology.The Journal is managed by a renowned international publisher John Wiley&Sons Australia,Ltd.and published quarterly in English.The Journal is devoted to building a mainstream academic exchange platform,focusing on forefront research and striving to become a world class scientific and technological journal.展开更多
Editorial Policy Asian Journal of Traditional Medicines is an international journal devoted to the advancement of research on traditional medicines.The followed areas are covered:scientific and technological developme...Editorial Policy Asian Journal of Traditional Medicines is an international journal devoted to the advancement of research on traditional medicines.The followed areas are covered:scientific and technological developments and research achievements in the fields of traditional medicine resources,medicinal material processing,pharmacognosy,natural medicinal chemistry,quality control,pharmacology,pharmacy,and clinical efficacy.It has columns for monographs,reviews,full research articles,short articles,newsletters and clinical case reports of traditional Chinese medicines.展开更多
City of Muskogee Animal Control Supervisor Phil Blair is known for his devotion to animals,but his quick thinking this week took that commitment to a whole new level-saving the life of an unborn baby deer after a trag...City of Muskogee Animal Control Supervisor Phil Blair is known for his devotion to animals,but his quick thinking this week took that commitment to a whole new level-saving the life of an unborn baby deer after a tragic accident.Blair was called to the scene of a deer struck by a car.Upon arrival,he found the mother deer had suffered four broken legs and sadly had to be put down to prevent further suffering.展开更多
Dear Editor,In recent years,multi-modal medical image fusion has received widespread attention in the image processing community.However,existing works on medical image fusion methods are mostly devoted to pursuing hi...Dear Editor,In recent years,multi-modal medical image fusion has received widespread attention in the image processing community.However,existing works on medical image fusion methods are mostly devoted to pursuing high performance on visual perception and objective fusion metrics,while ignoring the specific purpose in clinical applications.展开更多
The human habit of wearing fiber materials and interwoven fabric can be dated back to the prehistoric time. In recent years, efforts have been devoted to make flexible energy devices, e.g., solar cells, into fiber sha...The human habit of wearing fiber materials and interwoven fabric can be dated back to the prehistoric time. In recent years, efforts have been devoted to make flexible energy devices, e.g., solar cells, into fiber shape, further expanding the concept of fiber from cloth materials to modern onbody electronic devices.展开更多
Extensive effort has been devoted to the discovery,development,and validation of biomarkers for early disease diagnosis and prognosis as well as rapid evaluation of the response to therapeutic interventions.Genomic an...Extensive effort has been devoted to the discovery,development,and validation of biomarkers for early disease diagnosis and prognosis as well as rapid evaluation of the response to therapeutic interventions.Genomic and transcriptomic profiling are well-established means to identify disease-associated biomarkers.However,analysis of disease-associated peptidomes can also identify novel peptide biomarkers or signatures that provide sensitive and specific diagnostic and prognostic information for specific malignant,chronic,and infectious diseases.Growing evidence also suggests that peptidomic changes in liquid biopsies may more effectively detect changes in disease pathophysiology than other molecular methods.Knowledge gained from peptide-based diagnostic,therapeutic,and imaging approaches has led to promising new theranostic applications that can increase their bioavailability in target tissues at reduced doses to decrease side effects and improve treatment responses.However,despite major advances,multiple factors can still affect the utility of peptidomic data.This review summarizes several remaining challenges that affect peptide biomarker discovery and their use as diagnostics,with a focus on technological advances that can improve the detection,identification,and monitoring of peptide biomarkers for personalized medicine.展开更多
Phenolics are vital for the adaptation of plants to terrestrial habitats and for species diversity.Phenoloxidases(catechol oxidases,COs,and laccases,LACs)are responsible for the oxidation and polymerization of phenoli...Phenolics are vital for the adaptation of plants to terrestrial habitats and for species diversity.Phenoloxidases(catechol oxidases,COs,and laccases,LACs)are responsible for the oxidation and polymerization of phenolics.However,their origin,evolution,and differential roles during plant development and land colonization are unclear.We performed the phylogeny,domain,amino acids,compositional biases,and intron analyses to clarify the origin and evolution of COs and LACs,and analysed the structure,selective pressure,and chloroplast targeting to understand the species-dependent distribution of COs.We found that Streptophyta COs were not homologous to the Chlorophyta tyrosinases(TYRs),and might have been acquired by horizontal gene transfer from bacteria.COs expanded in bryophytes.Structural-functionality and selective pressure were partially responsible for the species-dependent retention of COs in embryophytes.LACs emerged in Zygnemaphyceae,having evolved from ascorbate oxidases(AAOs),and prevailed in the vascular plants and strongly expanded in seed plants.COs and LACs coevolved with the phenolic metabolism pathway genes.These results suggested that TYRs and AAOs were the first-stage phenoloxidases in Chlorophyta.COs might be the second key for the early land colonization.LACs were the third one(dominating in the vascular plants)and might be advantageous for diversified phenol substrates and the erect growth of plants.This work provided new insights into how phenoloxidases evolved and were devoted to plant evolution.展开更多
A specific detection system devoted to the detection of weak γ-activities from neutron-rich isotopes in an element-separated source was developed,and successfully used in a new determination of the half-life of the r...A specific detection system devoted to the detection of weak γ-activities from neutron-rich isotopes in an element-separated source was developed,and successfully used in a new determination of the half-life of the recently identified heavy neutron-rich nuclide 208Hg.This newly measured half-life is 41+5-4min,in agreement with the earlier one of 42+23-11 min obtained by radiochemical milking method,but experimental precision was improved.展开更多
Micro-mixing is an important mechanism, which works simultaneously with macro-mixing in chemical reactors in process industries, for achieving the best selectivity with respect to desired products. In about a half cen...Micro-mixing is an important mechanism, which works simultaneously with macro-mixing in chemical reactors in process industries, for achieving the best selectivity with respect to desired products. In about a half century, a huge amount of data and knowledge has been accumulated from theoretical and experimental studies on micromixing. Nevertheless, those results are mostly composites of simplified theoretical and empirical models, and the true nature of interactions of flow inhomogeneity and micro-mixing with chemical reaction has not been fully unveiled. This article reviews the progress in micro-mixing study in chemical reactors to date. A few important topics related to the nature, experimental evaluation, and numerical simulation of micro-mixing are addressed.Some suggestions are given hopefully to motivate more chemical engineers to devote their efforts to better understanding of micro-mixing in chemical reactors.展开更多
The recent discovery of three-dimensional(3D) topological insulators(TIs) has provided a fertile ground for obtaining further insights into electron localization in condensed matter systems.In the past few years,a...The recent discovery of three-dimensional(3D) topological insulators(TIs) has provided a fertile ground for obtaining further insights into electron localization in condensed matter systems.In the past few years,a tremendous amount of research effort has been devoted to investigate electron transport properties of 3D TIs and their low dimensional structures in a wide range of disorder strength,covering transport regimes from weak antilocalization to strong localization.The knowledge gained from these studies not only offers sensitive means to probe the surface states of 3D TIs but also forms a basis for exploring novel topological phases.In this article,we briefly review the main experimental progress in the study of the localization in 3D TIs,with a focus on the latest results on ultrathin TI films.Some new transport data will also be presented in order to complement those reported previously in the literature.展开更多
Since its establishment in 1980, Zoological Research(ZR) has continued to strive forward with the enthusiastic and generous support of every author and reader. ZR has been a loyal companion to many generations of rese...Since its establishment in 1980, Zoological Research(ZR) has continued to strive forward with the enthusiastic and generous support of every author and reader. ZR has been a loyal companion to many generations of researchers and scholars,who have not only witnessed the evolution of ZR, but also devoted themselves to helping ZR grow(Yao & Jiang, 2021).Here, at the beginning of a fresh year, we are honored to have the opportunity to express our deepest appreciation to you all.展开更多
Ever since Santiago Ramon y Cajal’s pioneering observations of precise neuronal structure,neuroscience has been devoted to deciphering how these individual brain cells engender the complexity that defines brain funct...Ever since Santiago Ramon y Cajal’s pioneering observations of precise neuronal structure,neuroscience has been devoted to deciphering how these individual brain cells engender the complexity that defines brain function.Understanding the fundamental processes of perception,cognition,and behavior through neural activity remains a major challenge in modern neuroscience.展开更多
This study reports on the propagation of elastic waves in 1D and 2D mass spring structures.An analytical and computation model is presented for the 1D and 2D mass spring systems with different examples.An enhancement ...This study reports on the propagation of elastic waves in 1D and 2D mass spring structures.An analytical and computation model is presented for the 1D and 2D mass spring systems with different examples.An enhancement in the band gap values was obtained by modeling the structures to obtain low frequency band gaps at small dimensions.Additionally,the evolution of the band gap as a function of mass value is discussed.Special attention is devoted to the local resonance property in frequency ranges within the gaps in the band structure for the corresponding infinite periodic lattice in the 1D and 2D mass spring system.A linear defect formed of a row of specific masses produces an elastic waveguide that transmits at the narrow pass band frequency.The frequency of the waveguides can be selected by adjusting the mass and stiffness coefficients of the materials constituting the waveguide.Moreover,we pay more attention to analyze the wave multiplexer and DE-multiplexer in the 2D mass spring system.We show that two of these tunable waveguides with alternating materials can be employed to filter and separate specific frequencies from a broad band input signal.The presented simulation data is validated through comparison with the published research,and can be extended in the development of resonators and MEMS verification.展开更多
In order to study discrete fractional Birkhoff equations for Birkhoffian systems,the method of isochronous variational principle is used in this paper. Discrete fractional Pfaff-Birkhoff principle in terms of time sca...In order to study discrete fractional Birkhoff equations for Birkhoffian systems,the method of isochronous variational principle is used in this paper. Discrete fractional Pfaff-Birkhoff principle in terms of time scales is presented. Discrete fractional Birkhoff equations with left and right discrete operators of Riemann-Liouville type are established and some special cases including classical discrete Birkhoff equations,discrete fractional Hamilton equations and discrete fractional Lagrange equations are discussed. Finally,an example is devoted to illustrate the results.展开更多
摘要In the annals of Indian literature and spirituality,few figures resonate as profoundly as Surdas,a 16th-century poet-saint whose works have transcended time and cultural boundaries.While he is primarily celebrated for his devotional hymns dedicated to Lord Krishna,a deeper exploration of his writings reveals a profound understanding of child psychology.Surdas,through his poetic lens,captures the essence of childhood,fostering a nuanced comprehension of the emotional and psychological landscape of children.This essay delves into the theme of Surdas as a master of child psychology,examining how his insights into the innocence,curiosity,and emotionality of children can be perceived as an early exploration of child development.At the heart of Surdas's poetry is a celebration of innocence,a quality that defines childhood.His verses often depict the playful antics of Krishna as a child,embodying the joy,spontaneity,and purity that characterize early life untouched by the burdens and complexities of adulthood.In his portrayal of Krishna’s mischievous Surdas encapsulates the essence of childlike wonder.In modern child psychology,curiosity is recognized as a vital element in learning and development.Surdas’s emphasis on the playful exploration of the world resonates with contemporary theories that advocate for experiential learning.By portraying Krishna as an inquisitive child,Surdas implicitly encourages adults to cultivate environments where children feel safe to ask questions,experiment,and engage with their surroundings.The paper is an earnest attempt to explain the key concepts of child psychology as perceived in the poetry of Surdas sagar saar.
摘要The Editorial Office of Water Science and Engineering would like to express their sincere appreciation to the following peer reviewers for their devotion of time and energy to the journal in the year 2025.
摘要ABOUT THIS JOURNAL.Launched in 1988,the Chinese Journal of Chemical Physics(CJCP)is devoted to reporting new and original experimental and theoret-ical research on interdisciplinary areas,with chemistry and physics groundwork of interest to r resear chers,faculty and students domestic and abroad in the fields of chemistry,physics,material and biological sciences and their interdisciplinary areas.
摘要Chinese Journal of Notural Mdicines(CINM,ISSN 2095-6975,original ISSN 1672-3651)was founded in May 2003 and is sponsored by China Pharmaceutical University and Chinese Phar-maccutical Association.The printed version of CINM is published monthly by Science Press and is web edition is published by Elsevier.CJNM is devoted to communications among pharmaccutical and medicinal plant scientists who are interested in the advance-ment of the botanical,chemical,and biological sciences related to natural medicines,ineluding traditional Chinese medicines(TCM).
摘要Aim&Scope:Journal of Mountain Science (JMS) is devoted to mountains and their surrounding lowlands-ecoregions of particular global importance,with a particular emphasis on the important highlands/mountains in the world.JMS mainly publishes academic and technical papers concerning environmental changes and sustainable development in mountain areas under natural conditions or/and with the influence of human activities.It also accepts book reviews,commentary,and reports on mountain research and introductions to mountain research organizations.
摘要Deep Underground Science and Engineering (DUSE) is a new international journal (Online ISSN:2770-1328;Print ISSN:2097-0668) launched by China University of Mining and Technology.The Journal is managed by a renowned international publisher John Wiley&Sons Australia,Ltd.and published quarterly in English.The Journal is devoted to building a mainstream academic exchange platform,focusing on forefront research and striving to become a world class scientific and technological journal.
摘要Editorial Policy Asian Journal of Traditional Medicines is an international journal devoted to the advancement of research on traditional medicines.The followed areas are covered:scientific and technological developments and research achievements in the fields of traditional medicine resources,medicinal material processing,pharmacognosy,natural medicinal chemistry,quality control,pharmacology,pharmacy,and clinical efficacy.It has columns for monographs,reviews,full research articles,short articles,newsletters and clinical case reports of traditional Chinese medicines.
摘要City of Muskogee Animal Control Supervisor Phil Blair is known for his devotion to animals,but his quick thinking this week took that commitment to a whole new level-saving the life of an unborn baby deer after a tragic accident.Blair was called to the scene of a deer struck by a car.Upon arrival,he found the mother deer had suffered four broken legs and sadly had to be put down to prevent further suffering.
基金supported by the National Natural Science Foundation of China(62176081,61922075,62171176)the Fundamental Research Funds for the Central Universities(JZ2020HGPA0111,JZ2021HGPA0061)the USTC Research Funds of the Double First-Class Initiative(KY2100000123)。
摘要Dear Editor,In recent years,multi-modal medical image fusion has received widespread attention in the image processing community.However,existing works on medical image fusion methods are mostly devoted to pursuing high performance on visual perception and objective fusion metrics,while ignoring the specific purpose in clinical applications.
基金supported by the Fok Ying-Tong Education Foundation for Young Teachers in the Higher Education Institutions of China (161067)the National Key Research and Development Program of China(2017YFA0206600)the National Natural Science Foundation of China (51773045, 21772030, 51922032, 21961160720)for financial support。
摘要The human habit of wearing fiber materials and interwoven fabric can be dated back to the prehistoric time. In recent years, efforts have been devoted to make flexible energy devices, e.g., solar cells, into fiber shape, further expanding the concept of fiber from cloth materials to modern onbody electronic devices.
基金The work was primarily supported by research funding provided by the National Cancer Institute(U01CA252965)Eunice Kennedy Shriver National Institute of Child Health and Human Development(R01HD090927 and R01HD103511)+2 种基金National Institute of Allergy and Infectious Diseases(R01AI144168)U.S.Department of Defense(W8IXWH1910926)National Institute of Neurological Disorders and Stroke(R21NS130542).
摘要Extensive effort has been devoted to the discovery,development,and validation of biomarkers for early disease diagnosis and prognosis as well as rapid evaluation of the response to therapeutic interventions.Genomic and transcriptomic profiling are well-established means to identify disease-associated biomarkers.However,analysis of disease-associated peptidomes can also identify novel peptide biomarkers or signatures that provide sensitive and specific diagnostic and prognostic information for specific malignant,chronic,and infectious diseases.Growing evidence also suggests that peptidomic changes in liquid biopsies may more effectively detect changes in disease pathophysiology than other molecular methods.Knowledge gained from peptide-based diagnostic,therapeutic,and imaging approaches has led to promising new theranostic applications that can increase their bioavailability in target tissues at reduced doses to decrease side effects and improve treatment responses.However,despite major advances,multiple factors can still affect the utility of peptidomic data.This review summarizes several remaining challenges that affect peptide biomarker discovery and their use as diagnostics,with a focus on technological advances that can improve the detection,identification,and monitoring of peptide biomarkers for personalized medicine.
基金This work received financial support from the National Natural Science Foundation in China(Grant No.32060175 and 32060043)Fundamental Research Projects of Yunnan Province(2022530401740002).
摘要Phenolics are vital for the adaptation of plants to terrestrial habitats and for species diversity.Phenoloxidases(catechol oxidases,COs,and laccases,LACs)are responsible for the oxidation and polymerization of phenolics.However,their origin,evolution,and differential roles during plant development and land colonization are unclear.We performed the phylogeny,domain,amino acids,compositional biases,and intron analyses to clarify the origin and evolution of COs and LACs,and analysed the structure,selective pressure,and chloroplast targeting to understand the species-dependent distribution of COs.We found that Streptophyta COs were not homologous to the Chlorophyta tyrosinases(TYRs),and might have been acquired by horizontal gene transfer from bacteria.COs expanded in bryophytes.Structural-functionality and selective pressure were partially responsible for the species-dependent retention of COs in embryophytes.LACs emerged in Zygnemaphyceae,having evolved from ascorbate oxidases(AAOs),and prevailed in the vascular plants and strongly expanded in seed plants.COs and LACs coevolved with the phenolic metabolism pathway genes.These results suggested that TYRs and AAOs were the first-stage phenoloxidases in Chlorophyta.COs might be the second key for the early land colonization.LACs were the third one(dominating in the vascular plants)and might be advantageous for diversified phenol substrates and the erect growth of plants.This work provided new insights into how phenoloxidases evolved and were devoted to plant evolution.
基金Supported by the National Natural Science Foundation of China under Grant No.19275053Fund of Chinese Academy of Sciences under Grant No.KJ-85.
摘要A specific detection system devoted to the detection of weak γ-activities from neutron-rich isotopes in an element-separated source was developed,and successfully used in a new determination of the half-life of the recently identified heavy neutron-rich nuclide 208Hg.This newly measured half-life is 41+5-4min,in agreement with the earlier one of 42+23-11 min obtained by radiochemical milking method,but experimental precision was improved.
基金Supported by the National Natural Science Foundation of China(21376243,91434126)National Key Research and Development Program(2016YFB0301702)+1 种基金the State Key Development Program for Basic Research of China(2012CB224806)Jiangsu National Synergetic Innovation Center for Advanced Materials
摘要Micro-mixing is an important mechanism, which works simultaneously with macro-mixing in chemical reactors in process industries, for achieving the best selectivity with respect to desired products. In about a half century, a huge amount of data and knowledge has been accumulated from theoretical and experimental studies on micromixing. Nevertheless, those results are mostly composites of simplified theoretical and empirical models, and the true nature of interactions of flow inhomogeneity and micro-mixing with chemical reaction has not been fully unveiled. This article reviews the progress in micro-mixing study in chemical reactors to date. A few important topics related to the nature, experimental evaluation, and numerical simulation of micro-mixing are addressed.Some suggestions are given hopefully to motivate more chemical engineers to devote their efforts to better understanding of micro-mixing in chemical reactors.
基金Project supported by the National Basic Research Program of China(Grant Nos.2012CB921703 and 2015CB921102)the National Natural Science Foundation of China(Grant Nos.61425015,11374337,and 91121003)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB070202)
摘要The recent discovery of three-dimensional(3D) topological insulators(TIs) has provided a fertile ground for obtaining further insights into electron localization in condensed matter systems.In the past few years,a tremendous amount of research effort has been devoted to investigate electron transport properties of 3D TIs and their low dimensional structures in a wide range of disorder strength,covering transport regimes from weak antilocalization to strong localization.The knowledge gained from these studies not only offers sensitive means to probe the surface states of 3D TIs but also forms a basis for exploring novel topological phases.In this article,we briefly review the main experimental progress in the study of the localization in 3D TIs,with a focus on the latest results on ultrathin TI films.Some new transport data will also be presented in order to complement those reported previously in the literature.
摘要Since its establishment in 1980, Zoological Research(ZR) has continued to strive forward with the enthusiastic and generous support of every author and reader. ZR has been a loyal companion to many generations of researchers and scholars,who have not only witnessed the evolution of ZR, but also devoted themselves to helping ZR grow(Yao & Jiang, 2021).Here, at the beginning of a fresh year, we are honored to have the opportunity to express our deepest appreciation to you all.
摘要Ever since Santiago Ramon y Cajal’s pioneering observations of precise neuronal structure,neuroscience has been devoted to deciphering how these individual brain cells engender the complexity that defines brain function.Understanding the fundamental processes of perception,cognition,and behavior through neural activity remains a major challenge in modern neuroscience.
摘要This study reports on the propagation of elastic waves in 1D and 2D mass spring structures.An analytical and computation model is presented for the 1D and 2D mass spring systems with different examples.An enhancement in the band gap values was obtained by modeling the structures to obtain low frequency band gaps at small dimensions.Additionally,the evolution of the band gap as a function of mass value is discussed.Special attention is devoted to the local resonance property in frequency ranges within the gaps in the band structure for the corresponding infinite periodic lattice in the 1D and 2D mass spring system.A linear defect formed of a row of specific masses produces an elastic waveguide that transmits at the narrow pass band frequency.The frequency of the waveguides can be selected by adjusting the mass and stiffness coefficients of the materials constituting the waveguide.Moreover,we pay more attention to analyze the wave multiplexer and DE-multiplexer in the 2D mass spring system.We show that two of these tunable waveguides with alternating materials can be employed to filter and separate specific frequencies from a broad band input signal.The presented simulation data is validated through comparison with the published research,and can be extended in the development of resonators and MEMS verification.
基金National Natural Science Foundations of China(Nos.11272227,11572212)the Innovation Program for Postgraduate in Higher Education Institutions of Jiangsu Province,China(No.KYLX15_0405)
摘要In order to study discrete fractional Birkhoff equations for Birkhoffian systems,the method of isochronous variational principle is used in this paper. Discrete fractional Pfaff-Birkhoff principle in terms of time scales is presented. Discrete fractional Birkhoff equations with left and right discrete operators of Riemann-Liouville type are established and some special cases including classical discrete Birkhoff equations,discrete fractional Hamilton equations and discrete fractional Lagrange equations are discussed. Finally,an example is devoted to illustrate the results.