bluuebunny/crossref_metadata_2025 huggingface dataset:
Long Distance Implantation of Vernacular Architecture Traditions: The Canadians in Early Louisiana
Authors: Edwards Jay D.
Published: December 2020

This study explores the architectural contributions of Canadians to Louisiana in the 18th century. One of the most revealing arenas in American architectural history concerns the origins of new vernacular traditions in locations being settled for the first time by Europeans. Between the late 15th and 18th centuries, many settlement experiments occurred along the coastlines of the Atlantic. Yet the dearth of reliable documentation from the earliest years of colonial establishment renders elusive a sound understanding of the factors which shaped these foundational architectural transformations. The result: a loss of understanding of the very essence of our American vernacular traditions. This study examines one such case for which a relative abundance of documentation survives—the Canadians in Louisiana. It traces the architectural transformations that materialized when Canadians attempted to found a new colony on the Mississippi Gulf Coast and the lower Mississippi River Valley, beginning in 1699.
Las batallas de Atapuerca y la (re)escritura novelesca de la historia
Authors: Soler Bistué Maximiliano A.
Published: December 2020

This work highlights and describes the specific way in which fictional discourse in Spanish gradually took shape and developed in the rewriting of history in the first half of the 13th century. The battle of Atapuerca (1054) is a milestone in the history of the Kingdom of Navarre. Since its first historiographical version preserved in the Historia silense (c. 1118-1126), the account of the battle of Atapuerca underwent modifications, amplifications and several recasts in its extensive dispersion in time and space. In the first place, the work presents a comparison between different Latin versions (mainly the Silense, the Chronicon mundi and De rebus Hispaniae) and several Castilian versions (the Versión crítica de la Estoria de España, the Crónica sanchina, the Crónica de Castilla and the Crónica general de 1344) of the battle of Atapuerca. Secondly, a detailed analysis of a late version of the battle is carried out taking into account the evolution of narrative prose in medieval Spanish. This version adopts the typical narrative forms of the fazaña, a minor Castilian legal genre. The work focuses at this point on the peculiar intersection between the legal mould provided by this short narrative form and the traditional historiographic matter. In the treatment of historical matter and in the peculiar presentation of motifs and characters in this episode, the fazaña shows striking features that many critics have identified as fictional or even novelesque.
Plausibilitat d’un ancestre comú entre les obres mitològiques de Joan Roís de Corella i les Transformacions de Francesc Alegre
Authors: Bescós Pere
Published: December 2020

Between the Transformacions of Francesc Alegre (c.1452 - c.1508) and the mythological proses of Joan Roís de Corellasome textual coincidences have been detected. Not without reservations, these coincidences have been explainedas Corellas influence on Alegre. This is the most satisfactory explanation, given Alegre’s admiration and imitation ofCorella’s prose, and Corella’s huge fame in the second half of the fifteenth century. However, Alegre knew earlier versionsof Ovid’s Metamorphoses, such as that by Francesc de Pinós (1416-1475), or the anonymous Castilian version, bothnowadays lost. And perhaps these versions were known by Corella too. The textual coincidences of these two authors havebeen analyzed here to determine if they respond to Corella’s direct influence or if, in some cases, they could be explainedby a common ancestor.
Un códice facticio de cancioneros manuscritos del siglo XVI
Authors: Rodado Ruiz Ana María
Published: December 2020

A complete codicological analysis of manuscript 2763 of the University Library of Salamanca. This is volume SA10, inthe acronym system proposed by Brian Dutton (1990-91), a codex that groups two independent cancionero manuscriptsof medieval poetry, dating from the early sixteenth century. This exhaustive study of the codex materiality is completedby counting and analysing its selected works and authors, as well as their layout and sequencing. The results allow us toformulate an hypothesis about the genesis of the volume and its complex process of copying and transmission.
Self-Translation in the Northern Renaissance: Jan van der Noot’s French Verse
Authors: Armstrong Adrian
Published: December 2020

The Brabantian poet Jan van der Noot (1539-95?) wrote in both Dutch and French, and composed several works in both languages. Sometimes the two versions were published separately: the Dutch collection Het Theatre and its French counterpart, Le Theatre, were each printed in London in 1568. More often, the versions appeared alongside each other in bilingual editions: Cort begryp der XII boeken Olympiados / Abregé des douze livres Olympiades (1579), Lofsang van Braband / Hymne de Braband (1580), and various short pieces reproduced in anthologies of Van der Noot’s poetry (1580-95). The present study contends that Van der Noot’s self-translations should be read as translations from Dutch to French, rather than from French to Dutch as scholars have commonly assumed. It examines Van der Noot’s self-translational strategies, focusing in particular on his handling of form and versification, and the role played by paratext and illustrations. In doing so, it offers an alternative perspective on a figure whose translational activity is generally considered to have operated in the opposite direction, introducing innovations into Dutch poetry by imitating the work of Ronsard and the Pléiade.
Alimentarse, cocinar, compartir: Una breve historia social de la comida
Authors: Aguirre Patricia Marcela
Published: December 2020

Este trabajo aborda el sistema alimentario como un sistema complejo, abierto al medio, como los organismos vivos. Recurre a los aportes de múltiples ciencias (antropología, nutrición, medicina, economía, entre otras), relacionando las partes analíticamente separadas, para señalar sus transformaciones en el tiempo y en el espacio. Estudia la organización social a través de millones de años para entender la sinergia entre medio ambiente, tecnología de extracción, estructura económico-política y las cocinas resultantes (con su construcción social de gustos) como factores condicionantes del enfermar y el morir. En resumen, hace una antropología de la comida apoyándose en un trípode de pensamiento crítico, enfoque relacional e historicidad.
Dietas milagrosas: Pautas alimentarias que causan problemas de salud
Authors: Soriano del Castillo Jose Miguel , Zarzo Llobell M. Inmaculada
Published: December 2020

A nivel global, 1.900 millones de adultos tienen sobrepeso, de los que 650 millones presentan obesidad, con las consiguientes repercusiones sobre la salud y la economía. El tratamiento de la obesidad implica estrategias como la actividad física y la planificación dietética, siempre y cuando sean realizadas por profesionales sanitarios. En las últimas décadas han aparecido dietas milagrosas, que tienen su origen a principios del siglo XX, y que pueden acarrear problemas de salud sobre sus usuarios. Una manera práctica de detectarlas es que prometen pérdidas rápidas de peso (más de 1 kg por semana), aseguran que se realizan sin esfuerzo, tienen restricciones excesivas de energía y excluyen de la dieta alimentos o nutrientes para el organismo.
The spacetime structure and properties of dust particle
Authors: Chen Guang  ,   东华大学信息科学与技术学院，上海  200051
Published: December 2020

The spacetime structure and properties of the solution of dust particle are discussed. We derive the discrete structure of interior space of dust particle, and prove that the matter ball in the interior of dust particle is a flat ball without coordinates and has minimal volume and unitariness. Then, we derive the radial geodesics in the interior and exterior spacetime of dust particle and prove its continuity. Finally, we expound the inherent links between matter, gravitation and spacetime which were brought to light in the solution of dust particle.
A novel multi-step adaptive prediction method for chaotic time series
Authors: Meng Qing-Fang  , Zhang Qiang  , Mu Wen-Ying  ,   (1)济南市半导体元件实验所，济南  250014; (2)山东大学信息科学与工程学院，济南  250100
Published: December 2020

Based on the short-term predictability of chaotic time series and the adaptive tracking chaotic trajectory of adaptive algorithm, a novel multi-step adaptive prediction method is proposed in this paper to resolve the problem of adjusting the filter parameters of the local adaptive prediction method during multi-step prediction. Simulation results show that this multi-step adaptive prediction method can be successfully used to make multi-step predictions, and its performance is better than that of the local adaptive prediction algorithm.
Cellular automaton model for moving-like block system and study of train’s delay propagation
Authors: Zhou Hua-Liang  , Gao Zi-You  , Li Ke-Ping  ,   北京交通大学交通运输学院，北京  100044
Published: December 2020

Based on the NaSch traffic model, we propose a cellular automaton traffic model for moving-like block system to simulate the railway traffic. We simulate the traffic phenomenon of delay propagation. We also investigate how the main facts including the length of location unit, train time interval and initial delay affect the delay propagation of trains.
Study on the traffic flow of weaving section in elevated road system with cellular automaton model
Authors: Lei Li  , Dong Li-Yun  , Song Tao  , Dai Shi-Qiang  ,   (1)山东大学能源与动力工程学院,济南  250061; (2)上海大学上海市应用数学和力学研究所，上海  200072
Published: December 2020

The weaving sections often turn into the bottleneck on the elevated roads. On the basis of the NS cellular automaton traffic model, the weaving section with one-lane main road was simulated and analyzed. For the free traffic flow, weaving almost has no influence on the system, even with increased weaving length. On the other hand, when the traffic flow is in congested state, weaving conflicts have negative effects on the system. The traffic condition will be improved with the increase of weaving length. Our simulation results suggest that the length of weaving sections need not to be inappropriately increased, and a proper moderate value should be chosen to get an optimal traffic condition.
Amplitude-squared squeezing of Roy-type even and odd nonlinear coherent states in a finite-dimensional Hilbert space
Authors: Meng Xiang-Guo  , Wang Ji-Suo  ,   聊城大学物理科学与信息工程学院,聊城  252059
Published: December 2020

The Roy-type even and odd nonlinear coherent states in a finite-dimensional Hilbert space are constructed. Their amplitude-squared squeezing effect, orthonormalized property, unitary property and completeness relations are discussed. The results reveal the existence of unitary property, completeness relations and non-orthonormalized property. There exists the amplitude-squared squeezing effect for the Roy-type even and odd nonlinear coherent states when the phase θ of parameter β meets the fixed condition. The relations between conditions of squeezing effect and parameters s,r and function f(n) are given. Finally using the numerical method, it is found that in some different ranges of r, the amplitude-squared squeezing effect exists in Roy-type even and odd nonlinear coherent states field in a finite-dimensional Hilbert space when the parameters s,θ and Lamb-Dike parameter η are given as the fixed value.
Resonance radiation trapping in alkaline-earth metal atomic lasers
Authors: Mao Bang-Ning  , Pan Bai-Liang  , Chen Gang  , Xia Ting-Ting  ,   浙江大学物理系，杭州  310027
Published: December 2020

The resonance radiation trapping in alkaline-earth metal atomic lasers were investigated according to Holstein's theory. The threshold temperature, ground-state density and resonant level effective lifetime of the resonance radiation trapping were calculated for Ca, Sr, and Ba atomic vapor lasers with different tube radii. The calculated threshold temperature is found to be in good agreement with the experimental laser-starting temperature, which indicates the resonance radiation trapping is a significant factor in establishing the population inversion of the resonance to metastable transition lasers.
Optical-stopping effect of As2S8 channel waveguide fabricated by method of photoinduced refractive index changes
Authors: Zou Lin-Er  , Chen Bao-Xue  , Chen Lin  , Yuan Yi-Fang  , Hiromi Hamanaka  , Mamoru Iso  ,   (1)日本东京农工大学化工系，日本东京  184-8588; (2)日本法政大学材料化学系，日本东京  184-8584; (3)上海理工大学光学与电子信息工程学院，上海  200093
Published: December 2020

The photorefractive phenomenon of As2S8 film is reported in this paper. An ultraviolet irradiation technique is presented and applied successfully to As2S8 channel waveguide preparation on the basis of analyzing these experimental data. This channel waveguide of As2S8 displays good characteristics of a waveguide using a guided mode excitation. It is found that the optical stopping effect of As2S8 channel waveguide has the rotential application owing to its switching function with the photo-optical effect.
Influence of tantalum doping on the thermal conduction of BaTiO3 materials
Authors: Wang Pei-Ji  , Zhou Zhong-Xiang  , Su Yan  , Rong Zhen-Yu  , Zhao Peng  , Zhang Feng-Jun  ,   (1)哈尔滨工业大学理学院, 哈尔滨  150001; (2)哈尔滨工业大学理学院, 哈尔滨  150001;济南大学理学院, 济南  250022; (3)济南大学理学院, 济南  250022
Published: December 2020

The thermal diffusivities of BaTiO3 materials are measured by phototh ermal technique at different pressures, sintering temperatures and tantalum dopi ng quantities. The effect of tantalum doping on thermal conduction of BaTiO3 materials is studied in this paper. When tantalum doping quantity is l ess than 1.5mol%, the diffusivity of BaTiO3 increase with the incre ase of the tantalum doping. When tantalum doping quantity is greater than 1.5mol %, the diffusivity of BaTiO3 decreases with the increase of the tan talum doping. The experimental results of doped BaTiO3 materials are analyzed and discussed.
Theoretical studies on electronic transport properties of six-membered heterocyclic molecules
Authors: Ma Yong  , Zou Bin  , Li Zong-Liang  , Wang Chuan-Kui  , Luo Yi  ,   (1)Laboratory of Theoretical Chemistry,Royal Institute of Technology,Stockholm   S-10691,Sweden; (2)山东师范大学物理与电子科学学院, 济南  250014
Published: December 2020

By applying the elastic scattering Green's function theory in combination with t he hybrid density function theory, the electronic transport properties of molecu lar junctions constructed by the six-membered heterocyclic molecules, pyridazine -2,5-dithiol, pyrazine-2,5-dithiol, and pyrimidine-2,5-dithiol, have been studie d. For the heterocyclic molecule pyridine, the influence of the terminal atoms o n the current-voltage characteristics has also been obtained. We have accurately determined the coupling constant between the molecule and electrodes by using t he frontier molecular orbital theory and the perturbation method. The numerical results show that pyridazine-2,5-dithiol has higher current and conductance, whi le the conductance of pyrimidine-2,5-dithiol is very small when the bias voltage is lower than 4V. The conductivity of the molecule pyridine with selenium atom as the terminal atom is higher than that with oxygen atom or sulfur atom.
Investigation of decay characteristics of photoelectrons in nanoparticales of cubic AgBr sensitized by NiS
Authors: Yang Shao-Peng  , Zheng Hong-Fang  , Li Chun-Lei  , Fu Guang-Sheng  , Li Xiao-Wei  , Xu Chun-Hua  , Li Jin-Pei  ,   (1)河北大学物理科学与技术学院，保定  071002; (2)中国科学院理化技术研究所，北京  100101
Published: December 2020

NiS nanoparticales as a sensitizer is added to cubic silver bromide emulsion for the chemical sensitization. The decay curves of free photoelectrons and shallow-trapped electrons in the cubic silver bromide emulsion sensitized by NiS nanoparticales with the continuous increase of sensitization time are measured by the microwave absorption and dielectric spectrum techniques. The courses of decay of photoelectrons in the cubic silver bromide emulsion sensitized by NiS nanoparticales vis sensitization time is analyzed. The influence of electron traps in silver bromide microcrystals on the behavior of the photoelectrons' movement is discussed. The relationships between the effects of electron traps and the depth of traps with sensitization time are analyzed. By comparing the decay characteristics of the unsensitized and the sensitized samples, the optimum sensitization time under the present experimental conditions is 80 min.
The experimental investigation of the neutron energy response of the thin ST-401 scintillator
Authors: Zhang Guo-Guang  , Ouyang Xiao-Ping  , Zhang Jian-Fu  , Wang Zhi-Qing  , Zhang Zhong-Bing  , Ma Yan-Liang  , Zhang Xian-Peng  , Chen Jun  , Zhang Xiao-Dong  , Pan Hong-Bo  , Luo Hai-Long  , Liu Yi-Na  ,   (1)西北核技术研究所,西安  710024; (2)西北核技术研究所,西安  710024；中国原子能科学研究院,北京  102413; (3)中国原子能科学研究院,北京  102413
Published: December 2020

Using the 5SDH-2 Accelerator at the Radiation Metrology Center of CIAE, the experiment of neutron energy response of the thin ST-401 scintillator has been performed. Two T(p,n)3 He and D(d,n)3He reactions are chosen for generating the neutrons. The neutron beam is collimated with the multiplex shielding system. The source intensity is monitored by the proportional counter or semiconductor proton recoil telescope. The neutron response curves of ST-401 scintillators with thickness from 0.16mm to 2.00mm are measured versus neutron energy. The uncertainties of experimental results are discussed in detail. The results show that the sensitivity increases with the scintillator thickness, and for the same thickness, the slope of energy response curve does not change greatly with the increase of neutron energy.
Structure and potential energy function of the ground state of XY(H, Li, Na)
Authors: Geng Zhen-Duo  , Fan Xiao-Wei  , Zhang Yan-Song  ,   河南师范大学物理学院,新乡  453007
Published: December 2020

In this paper, the electronic states of the ground state and dissociation limit of XY(H，Li，Na) are correctly determined based on group theory and atomic and molecular reaction statics. The equilibrium geometries, harmonic frequencies and dissociation energies of the ground state of XY(H，Li，Na) are calculated using DFT(B3LYP) method and Quadratic CI method including single and double substitutions (QCISD). The potential curves are scanned using the QCISD/6-311++G(3df,3pd) method for the ground state. The potential energy function and relevant optical constants (Be，αe，ωe and ωeχe) of this state are obtained by least square fitting to the Murrell-Sorbie function. All calculation results are in good agreement with experimental data.
Total cross sections for scattering of positron from CO, HCl, NH3 and CH4 at intermediate and high energies
Authors: Shi De-Heng  , Sun Jin-Feng  , Zhu Zun-Lue  , Liu Yu-Fang  ,   河南师范大学物理与信息工程学院，新乡  453007
Published: December 2020

A complex optical model potential modified by incorporating the concept of bonded atom, which takes into consideration the overlapping effect of electron clouds between two atoms in a molecule, is firstly employed to calculate the total cross sections for positron scattering from CO, HCl, NH3, SiH4 in the incident energy range 30—3000eV by using additivity rule model at Hartree-Fock level. In the study, the complex optical model potential composed of static, correlation polarization plus absorption contributions firstly uses the bonded-atom concept. The results of quantitative molecular total cross sections are compared with those obtained by experiments and other theories wherever available, and good agreement is obtained. It is shown that the additivity rule model together with the complex optical potential model modified by incorporating the concept of bonded atom can give much better calculation results than the unmodified one.
Structures and properties of small bimetallic PdnPbm(n+m≤5) clusters
Authors: Fang Fang  , Jiang Gang  , Wang Hong-Yan  ,   四川大学原子与分子物理研究所，成都  610065
Published: December 2020

The possible geometrical and electronic structures of small bimetallic Pd-Pb clusters including Pbn(n=2,3,4,5) and PdnPbm(n+m≤5) have been optimized by density functional theory(B3LYP/LANL2DZ) method with relativistic effective core potential(RECP) using Gaussian 98 code. The shaping regularities of small bimetallic Pd-Pb clusters is analyzed based on structures and vibration spectrum. Finally, the energy level distribution, HOMO-LUMO gaps and the chemical activation are discussed.
The effects of quantum measurement on an excited Λ-type atom in three-dimensional photonic crystal
Authors: Huang Xian-Shan  , Xie Shuang-Yuan  , Yang Ya-Ping  ,   同济大学物理系，上海  200092
Published: December 2020

We have studied the effects of quantum measurements on the decay of an excited Λ-type atom embedded in anisotropic photonic crystal. It is found that the decay of the atom can be suppressed os accelerated by the quantum measurements. This depends on the relative positions of the upper levels of the atom from the band edge and the frequency of the quantum measurements. Due to the effects of the anisotropic photonic crystal, the decay suppression effect can be obtained in relatively low frequencies of the quantum measurement.
Application of dynamic track method in output-section calculation of klystrons
Authors: Zhao Ding  , Ding Yao-Gen  , Sun Peng  , Wang Jin-Hua  ,   (1)中国科学院电子学研究所,北京  100080; (2)中国科学院电子学研究所,北京  100080；中国科学院研究生院,北京  100049
Published: December 2020

In the output section of klystrons, microwave energy is extracted from kinetic charged particles through beam-wave interaction process. In this region, the electron velocity will suffer violent changes, and some electrons may become so slow that they are overtaken by other ones. The traditional time integral method cannot track the laggard particles effectively, so its computation result is doubtful in the case of serious surpassing phenomenon existing in electron beam. To solve this problem, we present a new dynamic track method(DTM) that can correctly calculate the space charge force from other particles on the lagged ones. We will briefly explain DTM's principles and introduce a one-dimensional program based on this idea. Further, we apply this new program in output-section calculation of klystrons. The results show better agreement with experimental data than the traditional method.
Degradation of tunnel oxide in E2PROM under constant current stress
Authors: Li Lei-Lei  , Liu Hong-Xia  , Yu Zong-Guang  , Hao Yue  ,   西安电子科技大学微电子学院,宽禁带半导体材料与器件教育部重点实验室，西安  710071
Published: December 2020

The degradation of thin tunnel gate oxide under constant Fowler-Nordheim current stress was studied using capacitors.The degradation is a function of constant current and time，which depends more on the magnitude of constant current.Thus the degradation is a strong function of injected charge density Qinj. Positive charge trapping is usually dominant at lower Qinj followed by negative charge trapping at higher Qinj，causing a reversal of gate voltage change.
Experimental studies on the electronic structure of pyrite FeS2 films prepared by thermally sulfurizing iron films
Authors: Zhang Hui  , Wang Bao-Yi  , Zhang Ren-Gang  , Zhang Zhe  , Qian Hai-Jie  , Su Run  , Kui Re-Xi  , Wei Long  ,   (1)中国科学院高能物理研究所北京同步辐射实验室，北京  100049; (2)中国科学院高能物理研究所核分析技术重点实验室，北京  100049
Published: December 2020

Pyrite FeS2 films have been prepared by thermally sulfurizing iron films deposited by magnetron sputtering.The electronic structures were studies by X-ray absorption near edge structure and X-ray photoemission spectrum. The results show that an S 3p valence band with relatively higher intensity compared to the calculation exists in 2—10eV range and a high density below the Fermi level of Fe 3d states were detected.A second gap of 2.8eV in the unoccupied density of states was found above the conduction band which was 2.4eV by experimentally calculation.The difference between t2g and eg which were formed in an octahedral crystal field was computed to be 2.1eV.
Structure and martensitic transformation of the CoNiZ alloys
Authors: Dai Xue-Fang  , Liu He-Yan  , Yan Li-Qin  , Qu Jing-Ping  , Li Yang-Xian  , Chen Jing-Lan  , Wu Guang-Heng  ,   (1)河北工业大学材料学院，天津  300130; (2)中国科学院物理研究所北京凝聚态物理国家实验室，北京  100080
Published: December 2020

Structures of CoNiZ (Z＝Si, Sn, Sb, Ga) alloys have been investigated. We found that CoNiZ alloys have B2 structure with Z=Sn or Sb, but when Z=Si, the structure is fcc γ phase. When B2 structure coexists with γ phase in CoNiGa alloys, γ phase affects the temperature of martensitic transformation greatly. The structure of the alloy is determined by both the electron concentration and the size effect. The coexistence of two phases in the CoNiGa alloys can be changed by various heat treatment conditions. These results indicate that the martensitic transformation behaviors can be adjusted just by heat treatments, other than by modifying the composition as being done conventionally for other ferromagnetic shape memory materials.
The effect of Cu doping on the ordering of FexPt1－x thin films
Authors: Li Bao-He  , Feng Chun  , Yang Tao  , Zhai Zhong-Hai  , Teng Jiao  , Yu Guang-Hua  , Zhu Feng-Wu  ,   (1)北京科技大学材料物理系，北京  100083; (2)北京科技大学材料物理系，北京  100083；北京工商大学数理部，北京  100037; (3)北京科技大学材料物理系，北京  100083；沈阳建筑大学理学院，沈阳  110168
Published: December 2020

(FexPt1-x)100-yCuy(x=0.46—0.56,y=0,0.04,0.12) thin films with a fixed thickness of 50nm have been prepared by magnetron sputtering. The atomic ratio of Fe to Pt atoms was accurately controlled by DC co-sputtering. The ordering parameter of the L10 phase is not enhanced for the films with x>0.52. On the contrary, the ordering process is improved by the addition of Cu for the Pt-rich or stoichiometric thin films. In order to get the ordering of FePt films at a low annealing temperature, the lower the Fe content, the more addition of Cu is needed. It is found that the L10 phase can be obtained after annealing at 350℃ for 20 min only for films with the ratio of the (FeCu)/Pt in the range of 1.1—1.2.
Influence of heat treatment temperature after the pressure expansion on the electromechanical properties of cellular polypropylene electret
Authors: Qiu Xun-Lin  , Xia Zhong-Fu  , Wang Fei-Peng  ,   同济大学波耳固体物理研究所，上海  200092
Published: December 2020

The influence of heat treatment temperature after the pressure expansion on the electromechanical properties of cellular polypropylene (PP) electret is studied. The results point out that over the temperature range form RT to the melting temperature of the sample, the thickness of the sample after pressure expansion increases with the heat treatment temperature. Compared to that mentioned above, obviously different influence of heat treatment temperature on the electromechanical properties of cellular PP is observed. The elastic modulus and electromechanical coupling factor of cellular PP electret reach minimum and maximum at 90℃ heat treatment temperature, respectively. As a result, the piezoelectric d33 coefficient reaches its maximum of 377pC/N. Further, with the increase of heat treatment temperature, the resonance frequency of cellular PP could be regulated from about 794 to 371kHz.
Self-collimation and subwavelength lensing in wavy two-dimensional photonic crystals
Authors: Li Yi-Yu  , Gu Pei-Fu  , Li Ming-Yu  , Zhang Jin-Long  , Liu Xu  ,   浙江大学现代光学仪器国家重点实验室,杭州  310027
Published: December 2020

The equal-frequency surface of wavy two-dimensional (2D) photonic crystals (PC) is obtained by virtue of plane wave expansion method. From the equal-frequency surface, we find a iso-frequency contour of rectangular form. A flat dispersion relation exists at this frequency, which is suitable for the self-collimation. The finite-difference time-domain (FDTD) method is used to simulate the self-collimation in wavy 2DPC on which a Gaussian beam is incident at different angles. Subwavelength lensing by self-collimation is also available in wavy 2DPC. The resolution of 0.28λ is achieved when single source is employed in simulation. The resolution will gradually degrade as the source moves beyond the near-field domain.
Influence of Si—OH groups on properties and avoidance for SiCOH films prepared by decamethylcyclopentasiloxane electron cyclotron resonance plasma
Authors: Ye Chao  , Ning Zhao-Yuan  , Xin Yu  , Wang Ting-Ting  , Yu Xiao-Zhu  ,   苏州大学物理科学与技术学院，江苏省薄膜材料重点实验室，苏州  215006
Published: December 2020

This paper investigates the effect of Si—OH groups on dielectric property and leakage current of the SiCOH low dielectric constant films deposited by decamethylcyclopentasioxane (D5) electron cyclotron resonance plasma. The results show that the increasing of Si—OH content in the films can lead to the increasing of dielectric constant k, decreasing of leakage current and rise in dielectric dispersion. The increasing of k value is the result of compensation of the decreasing of k value originated from cage by the strong polarization of Si—OH groups. The decreasing of leakage current at high Si—OH content is due to the low connecting probability p of networks because the networks break at the terminal Si—OH groups. In the case of high ionization degree of D5 plasma, more Si—OH groups break and form Si—O—Si linkages by chemical condensation occurring between proximal Si—OH groups. As a result, the k value of SiCOH films can be further reduced.
Studies on the temperature and energy dependence of g factor in GaAs by femtosecond laser absorption quantum beats
Authors: Xu Hai-Hong  , Jiao Zhong-Xing  , Liu Xiao-Dong  , Lei Liang  , Wen Jin-Hui  , Wang Hui  , Lin Wei-Zhu  , Lai Tian-Shu  ,   中山大学光电材料与技术国家重点实验室，物理系，广州市  510275
Published: December 2020

Time-resolved elliptically polarized pump-probe spectroscopy developed by us is used to study spin relaxation dynamics of electrons in an intrinsic GaAs under an external magnetic field. Absorption quantum beats are observed and attributed to Larmor precession of electron spin around the magnetic field. The frequency of this quantum beat is used as a new method to measure electronic g factor with high accuracy. In this paper, this new method is utilized to investigate the temperature and energy dependence of electronic g factor in the intrinsic GaAs. It is found that electronic g factor increases with the temperature and energy of electrons, which is guitc different from the dependence predicted by k·p theory. An empirical formula is given to describe the temperature and energy dependence of g factor by fitting experimental data.
The universal forms of the dynamic equations of holonomic mechanical system in relative motion
Authors: Zhang Xiang-Wu  ,   陇东学院物理系，庆阳  745000
Published: December 2020

Based on the dynamic equations of particles system in non-inertial coordinate system, the higher order differential variational principle of relative motion for mechanical system is obtained, and the energy of higher order relative velocity of the mechanical system is introduced, the different kinds of higher order dynamic equations of holonomic mechanical system in relative motion are derived, and an example is given to illustrate the application of the results.
Anticontrol of chaos via direct time delay feedback
Authors: Ren Hai-Peng  , Liu Ding  , Han Chong-Zhao  ,   (1)西安交通大学电子与信息工程学院,西安  710049; (2)西安交通大学电子与信息工程学院,西安  710049；西安理工大学自动化与信息工程学院,西安  710048; (3)西安理工大学自动化与信息工程学院,西安  710048
Published: December 2020

Purposely generating chaos when useful becomes an increasing focus of chaos research. Direct time delay feedback is proposed for anticontrol of chaos, which generates chaos from non-chaotic systems. Compared with the indirect time delay feedback, direct time delay feedback control is simple and easy to realize. The proposed method has the same structure as the time delay feedback method proposed by Pyragas for chaos control, therefore, the proposed method can generate chaos when it is useful, and eliminate chaos, when it is harmful, which will provide the designer with maximum flexibility. Simulations with nonchaotic Chen system and Lorenz system show the effectiveness of the proposed method.
Influence of the interaction between atoms on the squeezing of light field and atomic lasers
Authors: Li Ming  , Sun Jiu-Xun  ,   电子科技大学物理电子学院,成都  610054
Published: December 2020

The Hamiltonian operator of a system of single-mode light field interacting with Bose-Einstein condensate (BEC) of two-level atoms is discussed in terms of the lattice-liquid model. It is indicated that the contribution of the interaction between atoms to the Hamiltonian was irrationally overestimated in the literature, so the Hamiltonian operator is improved in the present paper. Based on the improved Hamiltonian, the equations of motion of the photon and atomic operators are derived analytically. The relevant parameters in the model are estimated in connection with the BEC experimental conditions. The influence of the interaction between atoms in the BEC on the squeezing of light field and the atomic lasers is studied. The results show that the dependence of squeezing factor with atom number in BEC is different from that given in literature. and the fluctuations of two quadrature components of light evolve periodically with cosine law and the fluctuations of two quadrature components of the atomic laser can be squeezed.
Self-collimation of unpolarized electromagnetic waves in 2D photonic crystals
Authors: Shen Xiao-Peng  , Han Kui  , Shen Yi-Feng  , Li Hai-Peng  , Xiao Zheng-Wei  , Zheng Jian  ,   中国矿业大学理学院物理系，徐州  221008
Published: December 2020

The self-collimation of two polarization statcs of electromagnetic waves in two dimensional photonic crystals is studied by using finite-difference-time-domain(FDTD) method.It is proved that self-collimation can be realized in both transverse electric (TE) field and transverse magnetic (TM) field simultaneously by modification of the appropriate photonic crystal structures.Analysis and numerical simulation were carried out.This effect may be important for creating integrated optical circuits,and for improving the efficiency of light source.
Realization of an angular filter using one-dimensional photonic crystal containing negative refractive metamaterials
Authors: Xu Jing-Ping  , Wang Li-Gang  , Yang Ya-Ping  ,   (1)同济大学物理系,上海  200092; (2)浙江大学物理系光学研究所,杭州  310027
Published: December 2020

A new kind of one-dimension photonic crystal (PC) which can be used as an angular filter was studied. With the knowledge of resonance tunneling mechanism in zero average index PC, we find such PC must contain negative refractive metamaterials and its structure parameters should satisfy some special conditions. When electromagnetic wave of a given frequency incident on such PC, only those portions with incident angles identical with the special angle (or angles) can pass through such PC, while the others can not. Such filter would have wids applications in microwave and optical communications.
Application of dispersion compensator based on chirped fiber gratings in ultra long-haul DWDM system
Authors: Tan Zhong-Wei  , Ning Ti-Gang  , Liu Yan  , Chen Yong  , Cao Ji-Hong  , Dong Xiao-Wei  , Ma Li-Na  , Jian Shui-Sheng  ,   北京交通大学光波技术研究所，北京  100044
Published: December 2020

The dispersion management based on chirped fiber gratings in single channel system is studied by numerical simulation and tested in a 10Gb/s system on 1500km G.652 fiber. In this article, the suppression of the XPM effects by the random time delay between channels induced by the chirped fiber gratings is also studied. The special characteristics of the dispersion management based on chirped fiber gratings are found.
Fabrication of vanadium dioxide films at low temperature and researches on properties of the films
Authors: Wang Li-Xia  , Li Jian-Ping  , He Xiu-Li  , Gao Xiao-Guang  ,   中国科学院电子学研究所传感技术国家重点实验室，北京  100080
Published: December 2020

The vanadium oxide thin films are fabricated for microbolometer by radio frequency reactive sputtering at room temperature. The effects of the oxygen partial pressure on deposition rate, electrical properties and compositions of the films are discussed. Films consisting mainly of VO2 can be prepared by adjusting oxygen partial pressure. After oxidation annealing in air, the VO2 films with high temperature coefficients of resistivity (about -4%/℃) and low resistivity can be obtained. The square resistances of the films are in the range between 100 kΩ/squ to 300kΩ/squ. All films are deposited at room temperature and annealed at 400℃, which is compatible with MEMS (micro electromechanical systems) process.
The entanglement between the boundary qubits in the five-qubit Heisenberg XX open chain
Authors: Xi Xiao-Qiang  , Chen Wen-Xue  , Liu Qi  , Yue Rui-Hong  ,   (1)西安邮电学院应用数学与应用物理系，西安  710061; (2)西北大学现代物理研究所，西安  710069
Published: December 2020

Heisenberg XX open chain is very important in the study of quantum state transition. In this paper, we calculate the entanglement between the boundary qubits in the five-qubit Heisenberg XX open chain. When introducing magnetic impurity and system impurity and they satisfy linear relation, the system can be solved exactly, and there exist entanglement between the boundary qubits. Choosing the magnetic and system impurity properly, the boundary entanglement can get the maximal value 0.5.
Optimum exposure intervals for light-induced optical waveguides in lithium niobate crystals by laser micromachining
Authors: Xu Hong-Lai  , Zhang Peng  , Zhao Jian-Lin  , Gao Yu-Han  , Ye Zhi-Jun  , Yang De-Xing  ,   西北工业大学理学院光信息科学与技术研究所，西安  710072
Published: December 2020

The optimal exposure intervals for optical waveguides induced by laser micromachining in LiNbO3 crystals are theoretically and experimentally investigated. When the focused laser beams scan along different directions, the optimal intervals for waveguide fabrications are numerically specified by solving the photorefractive dynamic equations. The simulations show that the index distributions of the fabricated waveguides are strongly dependent on the optimal exposure interval, and the optimal exposure interval is not dependent on the scanning directions of the writing beam. When the writing beam scans the crystal along the c axis for sandwich illumination, optical waveguides cannot be fabricated efficiently. However, in this case, symmetric refractive index changes can be obtained. Experimental demonstrations are performed by scanning LiNbO3:Fe crystal with a focused green laser beam. The light-induced index changes are measured by digital holography. The experimental results conform to the theoretical analyses. Additionally, a Y-branche waveguide is experimentally formed and the results of the guiding tests are showed in this paper.
Theoretical analysis of laser cooling of Tm3+-doped fiber
Authors: Sun Hai-Sheng  , Jia You-Hua  , Ji Xian-Ming  , Yin Jian-Ping  ,   华东师范大学物理系，光谱学与波谱学教育部重点实验室，上海  200062
Published: December 2020

In recent years, thulium-doped fluorozirconate (ZBLANP) glass has become one of the promising materials in the field of the laser cooling of solids. However, up to date, the theoretical studies on the laser cooling of the Tm3+:ZBLANP fiber and their experimental results have not been reported. In this paper, we have developed a simple theoretical model to discuss some basic problems in the laser cooling of solids. The influences of the fluorescent quantum efficiency, the pump power, the change of fluorescence wavelength and the black-body radiation on the laser cooling effect for the Tm3+:ZBLANP fiber are discussed in some detail, and some interesting and important results are obtained. These results will provide the reliable theoretical basis for further experimental study on the laser cooling of the Tm3+:ZBLANP fiber.
Roughness and light scattering properties of ZrO2 thin films deposited by electron beam evaporation
Authors: Hou Hai-Hong  , Sun Xi-Lian  , Shen Yan-Ming  , Shao Jian-Da  , Fan Zheng-Xiu  , Yi Kui  ,   (1)中国科学院上海光学精密机械研究所，上海  201800; (2)中国科学院上海光学精密机械研究所，上海  201800;中国科学院研究生院，北京  100039
Published: December 2020

Zirconium oxide (ZrO2) coatings for 632.8nm center wavelength were deposited on the Ag layer by electron beam evaporation, optical thickness of which varied in the range of 80—480nm. Surface roughness and scattering characteristics of ZrO2 coatings with different thickness were investigated. It was found that with the gradually increase of the thickness, both roughness and total integrated scattering (TIS) of the samples decreased firstly and then increased. These results indicated that TIS of the samples mainly depended on the surface roughness. According to the uncorrelated surface roughness scattering model, scattering properties of the samples were analyzed theoretically. The calculated TIS values based on this model agreed well with that obtained by TIS measurements.
Structure and optical properties of Mn doped ZnO thin films
Authors: Zhao Yue-Zhi  , Chen Chang-Le  , Gao Guo-Mian  , Yang Xiao-Guang  , Yuan Xiao  , Song Zhou-Mo  ,   (1)华中科技大学激光技术国家重点实验室，武汉  430074; (2)西北工业大学理学院应用物理系，西安  710072; (3)西北工业大学理学院应用物理系，西安  710072；空军工程大学理学院，西安  710051
Published: December 2020

Mn-doped ZnO thin films were prepared on SiO2 substrate using pulsed laser deposition (PLD) technique in order to investigate the structure and optical properties of the films. XRD, AFM, EDX analysis and UV-VIS spectrophotometry were employed to characterize the Mn-doped ZnO films. The results showed that the shape of the XRD spectrum was remarkably similar to that of the un-doped ZnO film, indicating that the structure of the films was not disturbed by Mn-doping and the film also had mainly (103) peaks. The contents of (Zn, Mn)O thin films prepared by PLD were consistent with the targets, thus realizing the thin films deposition with same constitutuents as the target. The films had rather flat surfaces with the peak-to-tail roughness of about 80nm and an average grain diameter of about 25nm. Mn-doping changed the band gap of the films, which increased with the increase of the Mn content. Moreover, when the Mn content increased from 6% to 12%，the absorbence in strong UV absorption band increased too.
Effect of electron screening on the prompt explosion energy for type Ⅱ supernova
Authors: Liu Men-Quan  , Zhang Jie  , Luo Zhi-Quan  ,   西华师范大学理论物理研究所，四川南充  637002
Published: December 2020

The effect of electron screening on prompt explosion energy of supernova is discussed in regard to progenitor model WS15M⊙. The average heavy nuclei model is used for calculating the electron capture rates. The simulation results show that electron capture rate is decreased and the collapsing time-scale is prolonged by the electron screening, and the total energy of neutrino leakage increases. Acordingly, by the energy of the shock wave also decreases appreciably. The effect of electron screening on other supernova simulations is estimated.
A spectral blanking-out controller for demonstration of information barrier technology
Authors: Liu Su-Ping  , Gong Jian  , Hu Guang-Chun  , Zhang Jian-Hua  ,   中国工程物理研究院核物理与化学研究所，绵阳  621900
Published: December 2020

Information barrier technology has become more and more important in the R&D of radiation fingerprint verification associated with classified items such as nuclear warheads, nuclear components and military-used nuclear materials. The function of information barriers is two-fold: one is to prevent the classified information from leaking out; the other is to provide creditable verification. To fulfill these two functions, the information barriers for a viable verification system (including all its hardware and software) must be designed on the basic principles of protecting classified information and the ability to authenticate. The Spectral Blanking-out Controller (SBC) is developed to illustrate the two functions of the information barriers and to explore some practice measures to meet the required design fundamentals. This paper briefs the task assigned to the SBC, the specific design concerns and the practical information barrier measures. The R&D of the SBC embodies the concepts of information barrier technology and has to confom to the basic guidelines: If a verification system is expected to possess strict information barriers, the design of the system must be integrative with due considerations given to the factors such as the efficiency of the verification technique, the possible measures to protect the classified information from directly or indirectly leaking out, the complete openness in all aspects of the system for the inspectors to authenticate the system for the sake of achieving certain degree of confidence on the verification results.
Theoretical analysis and circuit implementation of a new four dimensional chaotic system
Authors: Zhang Yu-Hui  , Qi Guo-Yuan  , Liu Wen-Liang  , Yan Yan  ,   天津科技大学电子信息与自动化学院，天津  300222
Published: December 2020

This paper further analyzes some basic properties of a new complex four-dimensional continuous autonomous chaotic system, in which each equation contains a cubic cross-product term. The new system has 9 equilibria which display graceful symmetry with respect to the origin and coordinate planes, and they are similar with respect to their linearized characteristics and invariant manifolds. Two coexisting symmetric double-wing chaotic attractors are described. Finally, an analog circuit is designed to implement the new system, which shows a good agreement between numerical simulation and experimental results, and explains their significant distinction in applications due to difference in frequencies.
Energy eigenstates of two ions in a two-dimensional paul trap
Authors: Wu Yun-Wen  , Hai Wen-Hua  ,   湖南吉首大学物理系，吉首  416000;湖南师范大学物理系，长沙  410081
Published: December 2020

Taking into consideration the Coulomb interaction between two ions trapped in the coplanar Paul trap,the exact solutions of the Schrdinger equations of the two-ions system are obtained.The energy level degeneracy for center-of mass is obtained using the exact solutions. We also calculate the equilibrium distance of the ions and several state functions of the low energy levels. The radial probability distribution graph for the center of mass is plotted using a computer program.
Distribution of impurities on nonlattice substraes influence for fractal aggregates
Authors: Gao Guo-Liang  , Qian Chang-Ji  , Li Hong  , Gu Wen-Jing  , Huang Xiao-Hong  , Ye Gao-Xiang  ,   (1)温州大学物理系，温州  325035; (2)温州大学信息学院，温州  325035; (3)浙江大学物理系，杭州  310027
Published: December 2020

According to the experimental observation of Au atomic aggregations on a molten glass surface, we established a computational model to simulate Improved Restricted Cluster-Cluster Aggregation (IRCCA) on nonlattice substrates with regularly and randomly distributed impurities. In the model, the random diffusion step and rigidity rotation around the mass center of cluster were considered. The aggregation process was simulated and the influence of the distribution of impurity on the properties of aggregations was systemically investigated. The results show that regularly distributed impurities play a more important role in restricting the aggregation of clusters than randomly distributed impurities, resulting in a higher number density of fractal aggregates with smaller radius of gyration and fractal dimension.
Research on D→Klv～l decay
Authors: Wu Xiang-Yao  , Gong Pi-Feng  , Su Xi-Yu  , Liu Xiao-Jing  , Fan Xi-Hui  , Wang Li  , Shi Zong-Hua  , Guo Yi-Qing  ,   (1)吉林师范大学物理学院,  吉林  136000; (2)曲阜师范大学物理工程学院，曲阜  273165; (3)中国科学院高能物理研究所，北京  100049
Published: December 2020

In this paper, the D→Klv～l decay is researched using by QCD light cone sum rules. Firstly, the form factor of D→K is calculated by choosing a new correlative function to eliminate the effect caused by the uncertainty of twist-3 function, so the calculation result of form factor is more precise, and the branching ratio is consistent with the experimental data.