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Design of a high sensitivity and wide range angular rate sensor based on exceptional surface
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作者 丁鑫圣 刘文耀 +7 位作者 王师贤 陶煜 周彦汝 白禹 刘来 邢恩博 唐军 刘俊 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期277-286,共10页
It is found that when the parity–time symmetry phenomenon is introduced into the resonant optical gyro system and it works near the exceptional point,the sensitivity can in theory be significantly amplified at low an... It is found that when the parity–time symmetry phenomenon is introduced into the resonant optical gyro system and it works near the exceptional point,the sensitivity can in theory be significantly amplified at low angular rate.However,in fact,the exceptional point is easily disturbed by external environmental variables,which means that it depends on harsh experimental environment and strong control ability,so it is difficult to move towards practical application.Here,we propose a new angular rate sensor structure based on exceptional surface,which has the advantages of high sensitivity and high robustness.The system consists of two fiber-optic ring resonators and two optical loop mirrors,and one of the resonators contains a variable ratio coupler and a variable optical attenuator.We theoretically analyze the system response,and the effects of phase and coupling ratio on the system response.Finally,compared with the conventional resonant gyro,the sensitivity of this exceptional surface angular rate sensor can be improved by about 300 times at low speed.In addition,by changing the loss coefficient in the ring resonator,we can achieve a wide range of 600 rad/s.This scheme provides a new approach for the development of ultra-high sensitivity and wide range angular rate sensors in the future. 展开更多
关键词 exceptional surface exceptional points ring resonator angular rate sensing rotational direction recognition wide operating range
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Focused electron beam transport through a long narrow metal tube at elevated pressures in the forevacuum range
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作者 Ilya BAKEEV Kirill KARPOV +2 位作者 Aleksandr KLIMOV Efim OKS Aleksey ZENIN 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第1期128-134,共7页
We present here our investigations of the features of focused electron beam transport in free space at elevated pressures of a few pascals.We have explored the effect of the beam accelerating voltage,operating gas pre... We present here our investigations of the features of focused electron beam transport in free space at elevated pressures of a few pascals.We have explored the effect of the beam accelerating voltage,operating gas pressure,and magnetic focusing upon the trajectory of beam electrons in the crossover region,in particular on the beam convergence and divergence angles.It is shown that for the forevacuum pressure range of 2-5 Pa explored,a distinctive feature of the propagation of a focused electron beam with a current of up to 20 mA at an accelerating voltage of 10-20 kV is the difference in the angles of convergence(before the focus)and divergence(after the focus).Whereas at a low pressure of 2 Pa the divergence angle is smaller than the convergence angle,as the pressure increases the divergence angle increases and for pressures greater than 5 Pa the divergence angle is greater than the convergence angle.The results obtained were used in experiments on electron beam transport through a long narrow metal tube with a diameter of 5.8-9.2 mm and length of 10-30 cm.We show that for a 30 cm long tube of 7.5 mm diameter,the focused beam transmission can exceed 70%. 展开更多
关键词 focused electron beam plasma electron source forevacuum pressure range long metal tube
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STATISTICAL PROPERTIES OF LONG-RANGE CONTACTS IN GLOBULAR PROTEINS
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作者 王向红 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2004年第2期187-194,共8页
The analysis of residue-residue contacts in protein structures can shed some light on our understanding of the folding and stability of proteins. In this paper, we study the statistical properties of long-range and sh... The analysis of residue-residue contacts in protein structures can shed some light on our understanding of the folding and stability of proteins. In this paper, we study the statistical properties of long-range and short-range residue- residue contacts of 91 globular proteins using CSU software and analyze the importance of long-range contacts in globular protein structure. There are many short-range and long-range contacts in globular proteins, and it is found that the average number of long-range contacts per residue is 5.63 and the percentage of residue-residue contacts which are involved in long- range ones is 59.4%. In more detail, the distribution of long-range contacts in different residue intervals is investigated and it is found that the residues occurring in the interval range of 4-10 residues apart in the sequence contribute more long-range contacts to the stability of globular protein. The number of long-range contacts per residue, which is a measure of ability to form residue-residue contacts, is also calculated for 20 different amino acid residues. It is shown that hydrophobic residues (including Leu, Val, He, Met, Phe, Tyr, Cys and Trp) having a large number of long-range contacts easily form long-range contacts, while the hydrophilic amino acids (including Ala, Gly, Thr, His, Glu, Gln, Asp, Asn, Lys, Ser, Arg, and Pro) form long-range contacts with more difficulty. The relationship between the Fauchere-Pliska hydrophobicity scale (FPH) and the number of short-range and long-range contacts per residue for 20 amino acid residues is also studied. An approximately linear relationship between the Fauchere-Pliska hydrophobicity scale (FPH) and the number of long-range contacts per residue CL, is found and can be expressed as CL = a + b × FPH where a = 5.04 and b = 1.23. These results can help us to understand the role of residue-residue contacts in globular protein structure. 展开更多
关键词 long-range and short-range contact Structural class Globular protein CSU software
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Electronic properties of one-dimensional systems with long-range correlated binary potentials
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作者 Gong Long-Yan Tong Pei-Qing Zhou Zi-Cong 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第8期335-339,共5页
We study numerically the electronic properties of one-dimensional systems with long-range correlated binary potentials. The potentials are mapped from binary sequences with a power-law power spectrum over the entire f... We study numerically the electronic properties of one-dimensional systems with long-range correlated binary potentials. The potentials are mapped from binary sequences with a power-law power spectrum over the entire frequency range, which is characterized by correlation exponent β. We find the localization length ζ increases withβ. At system sizes N →∞, there are no extended states. However, there exists a transition at a threshold ζ. Whenβ 〉 βc, we obtain ζ 〉 0. On the other hand, at finite system sizes, ζ≥ N may happen at certain β, which makes the system "metallic", and the upper-bound system size N* (β) is given. 展开更多
关键词 electronic properties long-range correlation binary potentials LOCALIZATION
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Characterizing Long-range Correlation Properties in Nucleotide Sequences
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作者 XiaoYanCHEN LunJunBAO +1 位作者 JinYuanMO YingWANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第5期503-504,共2页
Using continuous wavelet transform as the analytical tool, the fractal characteristic of nucleotide sequences was studied. The fractal dimension of the exon and intron sequences for different species was calculated. ... Using continuous wavelet transform as the analytical tool, the fractal characteristic of nucleotide sequences was studied. The fractal dimension of the exon and intron sequences for different species was calculated. We use the Mexican hat wavelet function as the mother wavelet and Hurst exponent to describe the long-range correlation. It is found that the Hurst exponent of intron sequence is larger than that of exon sequence for the same gene. 展开更多
关键词 Nucleotide sequences long-range correlation wavelet transform.
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Ag、Cu、Au、Ni、Pd、Pt的Long-range Finis-Sinclair势构建及其二元合金形成焓的计算
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作者 刘艳侠 顾慧 +2 位作者 刘磊 孙佳佳 高岩 《辽宁大学学报(自然科学版)》 CAS 2009年第3期193-196,共4页
构建了fcc金属Cu、Ag、Au、Ni、Pd、Pt的Long-range Finnis-Sinclair势,并利用晶格常数、体弹性模量和金属的内聚能的实验数据拟合了这几种金属的Long-range Finnis-Sinclair势参数;利用Miedema理论和所构建的原子间相互作用势计算了Cu,... 构建了fcc金属Cu、Ag、Au、Ni、Pd、Pt的Long-range Finnis-Sinclair势,并利用晶格常数、体弹性模量和金属的内聚能的实验数据拟合了这几种金属的Long-range Finnis-Sinclair势参数;利用Miedema理论和所构建的原子间相互作用势计算了Cu,Ag,Au,Ni,Pd,Pt的二元合金的形成焓.对两种计算结果进行了比较,并与已有的实验结果进行了比较.结果表明,使用Long-range Finnis-Sinclair势计算合金的形成焓能够得到令人满意的结果. 展开更多
关键词 long-range Finnis-Sinclair势 MIEDEMA理论 形成焓
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Respective Roles of Short-and Long-Range Interactions in Protein Folding 被引量:3
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作者 WANGLong-hui HUMin +1 位作者 ZHOUHuai-bei LIUJuan 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第6期962-966,共5页
A new method was presented to discuss the respective roles of short- and long-range interactions in protein folding. It's based on an off-lattice model, which is also being called as toy model. Simulated annealing... A new method was presented to discuss the respective roles of short- and long-range interactions in protein folding. It's based on an off-lattice model, which is also being called as toy model. Simulated annealing algorithm was used to search its native conformation. When it is applied to analysis proteins 1agt and 1aho, we find that helical segment cannot fold into native conformation without the influence of long-range interactions. That's to say that long-range interactions are the main determinants in protein folding. Key words toy model - protein folding - simulated annealing algorithm - short and long range interactions CLC number O 242.28 - Q71 Foundation item: Supported by the National Natural Science Foundation of China((60301009)Biography: WANG Long-hui (1976-), female, Ph. D candidate, research direction: machine learning, bioinformatics. 展开更多
关键词 toy model protein folding simulated annealing algorithm short and long range interactions
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Estimation of Thermal Imaging System Operating Range Based on Background Radiation 被引量:1
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作者 Tingzhu Bai Long Shao +1 位作者 Heng He Peishan Song 《Journal of Beijing Institute of Technology》 EI CAS 2018年第2期241-249,共9页
Traditional operating range prediction methods assume that the atmospheric radiances in a target path and a background path are equal. But they are different in a real-world environment. To solve this problem,the infl... Traditional operating range prediction methods assume that the atmospheric radiances in a target path and a background path are equal. But they are different in a real-world environment. To solve this problem,the influence of atmospheric radiance on operating range prediction is analyzed in this paper. Range estimation model in thermal imaging based on background radiation( REBR) is proposed. Infrared image radiometric calibration is used to calculate the background radiation of a system entrance pupil. The result shows that,compared with traditional operating range prediction methods,the REBR method is more suitable for the actual atmospheric transmission process and the physical process of infrared imaging. 展开更多
关键词 atmospheric radiance operating range background radiation radiometric calibration
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SOME PROPERTIES OF THE INTEGRATION OPERATORS ON THE SPACES F(p,q,s)
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作者 陈家乐 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期173-188,共16页
We study the closed range property and the strict singularity of integration operators acting on the spaces F(p,pα-2,s).We completely characterize the closed range property of the Volterra companion operator I_(g)on ... We study the closed range property and the strict singularity of integration operators acting on the spaces F(p,pα-2,s).We completely characterize the closed range property of the Volterra companion operator I_(g)on F(p,pα-2,s),which generalizes the existing results and answers a question raised in[A.Anderson,Integral Equations Operator Theory,69(2011),no.1,87-99].For the Volterra operator J_(g),we show that,for 0<α≤1,J_(g)never has a closed range on F(p,pα-2,s).We then prove that the notions of compactness,weak compactness and strict singularity coincide in the case of J_(g)acting on F(p,p-2,s). 展开更多
关键词 integration operator closed range property strict singularity
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Supercapacitor electrode based on few-layer h-BNNSs/rGO composite for wide-temperature-range operation with robust stable cycling performance 被引量:3
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作者 Tao Yang Hui-juan Liu +4 位作者 Fan Bai En-hui Wang Jun-hong Chen Kuo-Chih Chou Xin-mei Hou 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2020年第2期220-231,共12页
Currently,developing supercapacitors with robust cycle stability and suitability for wide-temperature-range operations is still a huge challenge.In the present work,few-layer hexagonal boron nitride nanosheets(h-BNNSs... Currently,developing supercapacitors with robust cycle stability and suitability for wide-temperature-range operations is still a huge challenge.In the present work,few-layer hexagonal boron nitride nanosheets(h-BNNSs)with a thickness of 2−4 atomic layers were fabricated via vacuum freeze-drying and nitridation.Then,the h-BNNSs/reduced graphene oxide(rGO)composite were further prepared using a hydrothermal method.Due to the combination of two two-dimensional(2D)van der Waals-bonded materials,the as-prepared h-BNNSs/rGO electrode exhibited robustness to wide-temperature-range operations from−10 to 50℃.When the electrodes worked in a neutral aqueous electrolyte(1 M Na2SO4),they showed a great stable cycling performance with almost 107%reservation of the initial capacitance at 0℃ and 111% at 50℃ for 5000 charge−discharge cycles. 展开更多
关键词 few-layer hexagonal boron nitride wide-temperature-range operation cycling performance
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Preliminary research on the relationship between long-range correlations and predictability 被引量:1
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作者 张志森 龚志强 +2 位作者 支蓉 封国林 胡经国 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第1期23-32,共10页
By establishing the Markov model for a long-range correlated time series (LRCS) and analysing its evolutionary characteristics, this paper defines a physical effective correlation length (ECL) T, which reflects th... By establishing the Markov model for a long-range correlated time series (LRCS) and analysing its evolutionary characteristics, this paper defines a physical effective correlation length (ECL) T, which reflects the predictability of the LRCS. It also finds that the ECL has a better power law relation with the long-range correlated exponent γ of the LRCS: T = Kexp(-γ/0.3) + Y, (0 〈 γ〈 1) the predictability of the LRCS decays exponentially with the increase of γ It is then applied to a daily maximum temperature series (DMTS) recorded at 740 stations in China between the years 1960-2005 and calculates the ECL of the DMTS. The results show the remarkable regional distributive feature that the ECL is about 10-14 days in west, northwest and northern China, and about 5-10 days in east, southeast and southern China. Namely, the predictability of the DMTS is higher in central-west China than in east and southeast China. In addition, the ECL is reduced by 1-8 days in most areas of China after subtracting the seasonal oscillation signal of the DMTS from its original DMTS; however, it is only slightly altered when the decadal linear trend is removed from the original DMTS. Therefore, it is shown that seasonal oscillation is a significant component of daily maximum temperature evolution and may provide a basis for predicting daily maximum temperatures. Seasonal oscillation is also significant for guiding general weather predictions, as well as seasonal weather predictions. 展开更多
关键词 long-range correlation information entropy effective correlation length PREDICTABILITY
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Long Range, Long Lived and Gauge Invariant Massive Photons via Stückelberg Scalar Coupling 被引量:1
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作者 Golden Gadzirayi Nyambuya 《Journal of Modern Physics》 2016年第1期7-24,共18页
It is largely believed (or strongly assumed) that photons are massless particles and the most compelling evidence there—it is said—is found in the manifestations of photons being long ranged and long lived particles... It is largely believed (or strongly assumed) that photons are massless particles and the most compelling evidence there—it is said—is found in the manifestations of photons being long ranged and long lived particles. As we have done before, albeit, with a much better and clear insight in the present than before;we argue herein that massive photons can still enjoy the special and rare privilege of travelling at the speed of light c while being long ranged, long lived and most of all, obeying the much desired gauge symmetry. This we achieve by breaking the traditional Lorenz gauge and in its place, we introduce a new Special Gauge Condition (SGC) that does the work of assuring the photon its longevity, long range-ness and that it [photon] propagates at the speed c. However, the most melancholic outcome of our investigation is that if the present scheme is what subtle Nature has chosen to endow the photon a non-zero mass so that it [photon] still obeys gauge invariance, is long ranged, long lived and travels at the sacred speed c;then, this non-zero photon mass may be very difficult, if not impossible to measure. We use the equations developed to investigate Lorentz violation in ?-ray bursts. 展开更多
关键词 Lorentz Violation Lorenz Gauge: Violation Stueckelberg: Field Mechanism-Proca: Massive Photon long range Photon long Lived Photon
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Entanglement in a two-spin system with long-range interactions
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作者 Soltani M R Mahdavifar S Mahmoudi M 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第8期369-372,共4页
The quantum entanglement between two spins in the Ising model with an added Dzyaloshinsky–Moriya(DM) interaction and in the presence of the transverse magnetic field is studied. The exchange interaction is consider... The quantum entanglement between two spins in the Ising model with an added Dzyaloshinsky–Moriya(DM) interaction and in the presence of the transverse magnetic field is studied. The exchange interaction is considered as a function of the distance between spins. The negativity as a function of magnetic field, exchange and DM interaction is calculated.The effect of the distance between spins is studied based on the negativity. In addition, the effect of the thermal fluctuation on the negativity is also investigated. 展开更多
关键词 ENTANGLEMENT Ising model DM interaction NEGATIVITY long range interaction
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LAMELLAR STRUCTURE IN LONG RANGE ORDERED PHASE δ′-TiN_(0.5)
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作者 Yang, Caiying Du, Jun Shi, Likai 《中国有色金属学会会刊:英文版》 EI CSCD 1997年第3期8-14,共7页
LAMELLARSTRUCTUREINLONGRANGEORDEREDPHASEδ′TiN0.5①YangGaiying,DuJun,ShiLikaiGeneralResearchInstituteforNonf... LAMELLARSTRUCTUREINLONGRANGEORDEREDPHASEδ′TiN0.5①YangGaiying,DuJun,ShiLikaiGeneralResearchInstituteforNonferrousMetals,Beij... 展开更多
关键词 LAMELLAR STRUCTURE δ′ TIN 0.5 long range ORDERING transformation
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Fluctuations and pseudo long range dependence in network flows: A non-stationary Poisson process model
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作者 陈煜东 李力 +1 位作者 张毅 胡坚明 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第4期1373-1379,共7页
In the study of complex networks (systems), the scaling phenomenon of flow fluctuations refers to a certain powerlaw between the mean flux (activity) (Fi) of the i-th node and its variance σi as σi α (Fi)α... In the study of complex networks (systems), the scaling phenomenon of flow fluctuations refers to a certain powerlaw between the mean flux (activity) (Fi) of the i-th node and its variance σi as σi α (Fi)α Such scaling laws are found to be prevalent both in natural and man-made network systems, but the understanding of their origins still remains limited. This paper proposes a non-stationary Poisson process model to give an analytical explanation of the non-universal scaling phenomenon: the exponent α varies between 1/2 and 1 depending on the size of sampling time window and the relative strength of the external/internal driven forces of the systems. The crossover behaviour and the relation of fluctuation scaling with pseudo long range dependence are also accounted for by the model. Numerical experiments show that the proposed model can recover the multi-scaiing phenomenon. 展开更多
关键词 SCALING long range dependence non-stationary Poisson process
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Self-sustained target waves in excitable media with only a long-range link 被引量:1
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作者 钱郁 王参军 +2 位作者 石虎山 弭元元 黄晓东 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第10期457-462,共6页
In this paper we investigate spatiotemporal pattern formation in excitable media with only a long-range link. Besides the trivial solutions of spiral patterns, we find the asymptotic self-sustained target waves in the... In this paper we investigate spatiotemporal pattern formation in excitable media with only a long-range link. Besides the trivial solutions of spiral patterns, we find the asymptotic self-sustained target waves in the autonomous tissues. The wave source supporting this kind of new pattern is the oscillatory one-dimensional Winfree-loop self- organized under the presence of a long-range link, which is explored by the dominant phase-advanced driving method. Based on this understanding we can effectively regulate the oscillations of excitable media by suitably arranging the long-range link, including construction of self-sustained target waves with controllable period and wave length, or manipulation of system states between different patterns. 展开更多
关键词 self-sustained target waves long-range link one-dimensional Winfree-loop
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The Impact of Long Range Dependence of VBR Video Traffic in Queueing System
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作者 刘昀 孙海荣 《High Technology Letters》 EI CAS 1998年第1期34-38,共5页
he objective of the paper is to clarify the contradictory opinions about the effect of long range dependence (LRD) on the performance of queueing system. In order to investigate the impact of the value of LRD on the p... he objective of the paper is to clarify the contradictory opinions about the effect of long range dependence (LRD) on the performance of queueing system. In order to investigate the impact of the value of LRD on the performance of queueing system, a particular source (Star War) is used, whose Pframe and Bframe show the same frame size distribution and the same autocorrelation structure (i.e. the similar SRD and LRD) and the different values. The “Shuffling Operation” changing the order of original time series in some way is used to remove either SRD or LRD. The conditions under which LRD or SRD makes the dominant impact on single server FIFO queue and the importance of the amount of LRD are found after a set of queueing experiments. 展开更多
关键词 VBR VIDEO long range DEPENDENCE Shuffle
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Short-range action and long-range action of the electrostatic forces within atomic nuclei 被引量:1
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作者 Dragia Ivanov Kiril Kolikov 《Natural Science》 2013年第4期508-513,共6页
We study the interaction forces in atomic nuclei based on our expressions for the electrostatic interaction between spheres of arbitrary radii and charges. We prove that at small distances the proton-neutron electrost... We study the interaction forces in atomic nuclei based on our expressions for the electrostatic interaction between spheres of arbitrary radii and charges. We prove that at small distances the proton-neutron electrostatic attraction forces are short-range-acting and the proton-proton electrostatic repulsion forces are long-range-acting. We obtain that these forces are commensurate with the nuclear forces. The protonneutron electrostatic attraction forces and the proton-proton electrostatic repulsion forces at the same distance between nucleons differ in absolute value by about an order of magnitude. It follows that based on electromagnetic interactions the neutrons are the binding building blocks in nuclear structures. 展开更多
关键词 NUCLEON Electrostatic Force of INTERACTION Strong INTERACTION long-range-Acting FORCES Short-range-Acting FORCES
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Closed Range Composition Operators on a General Family of Function Spaces
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作者 M.A.Bakhit 《Analysis in Theory and Applications》 CSCD 2016年第3期215-231,共17页
In this paper, necessary and sufficient conditions for a closed range composition operator CФ on the general family of holomorphic function spaces F(p,q,s) and more generally on α-Besov type spaces F(p,αp-2,s) ... In this paper, necessary and sufficient conditions for a closed range composition operator CФ on the general family of holomorphic function spaces F(p,q,s) and more generally on α-Besov type spaces F(p,αp-2,s) are given. We give a Carleson measure characterization on F (p, αp - 2, s) spaces, then we indicate how Carleson measures can be used to characterize boundedness and compactness of CФ on F(p,q,s) and F(p,αp- 2,s) spaces. 展开更多
关键词 Composition operators F(p q s) spaces closed range Carleson measure Bloch space Bergman type space
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Nearly Perfect Absorbers Operating Associated with Fano Resonance in the Infrared Range
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作者 黄万霞 赵国任 +2 位作者 郭娟娟 汪茂胜 石建平 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第8期131-134,共4页
We fabricate a three-layer metamaterial of metal patterns/dielectric/metal films. The optical properties associated with Fano resonance of the metamaterials are investigated experimentally and theoretically. The resul... We fabricate a three-layer metamaterial of metal patterns/dielectric/metal films. The optical properties associated with Fano resonance of the metamaterials are investigated experimentally and theoretically. The results indicate that the introduction of Fano resonance due to symmetry breaking leads to a much wider absorption range. Furthermore, the amplitude and phase of reflection can be modulated effectively by adjusting various free parameters using the proposed structure. 展开更多
关键词 with or on of Nearly Perfect Absorbers operating Associated with Fano Resonance in the Infrared range in MODE is
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