bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis and calculation of the modulation depth of the Michelson interferometer with wide field, chromatic compensation and thermal compensation
Authors: Bu Zhi-Chao  , Zhang Chun-Min  , Zhao Bao-Chang  , Zhu Hua-Chun  ,   (1)西安交通大学理学院,西安  710049; (2)中国科学院西安光学精密机械研究所,西安  710068
Published: December 2020

Principle of the measurement of the upper atmospheric wind field using a Michelson interferometer with wide field, chromatic compensation and thermal compensation is briefly described. The modulation depth of the selfdeveloped wind imaging interferometer is analyzed and calculated, and the expression of the modulation depth is derived. Computer simulation is adopted, and the dependence of the modulation depth on the angle is analyzed. The field of view of the wind imaging interferometer is 129°when modulation depth is greater than 075, which fully shows the advantages of wide field and high modulation depth. The dependence of the modulation depth on the refractive index of glass is analyzed, and the optimized material is given. The dependence of the modulation depth on temperature is analyzed, and the curve is given. The research has important theoretical significance and practical value both for the research and development of the Michelson Interferometer with wide field, chromatic compensation and thermal compensation and the detection of the upper atmospheric wind field.
Overlap factor between intensity profiles of signal and pump light and gain characteristics of Er-doped waveguide amplifier
Authors: Shao Gong-Wang  , Dai Ya-Jun  , Jin Guo-Liang  ,   上海交通大学物理系，上海  200240
Published: December 2020

The model used for analyzing the gain characteristics of Erdoped waveguide amplifier （EDWA） is based on the ratepropagation equations with intensity profiles of pump and signal light. The intensity profiles of pump and signal light for different channel opening width （DCOW） of Erdoped waveguide is discussed. And the numerical method （NM） considering the difference of intensity profiles between signal and pump light in channel waveguide with DCOW is used to solve the gain characteristics of signal light in EDWA. An overlap factor Γsp between light intensity profiles of signal and pump is introduced to modify the conventional simplified method （CSM） in EDWA, which is a revised version of the conventional simplified method （RCSM）. Results show that difference of 297 dB in gain for -10 dBm signal light at 1534 nm due to DCOW of waveguides is obtained for a 4 cm long waveguide amplifier pumped by 80 mw at 980 nm. Comparing with CSM, the gain characteristics of EDWA from RCSM is simpler and better approaches the result from NM. Therefore, the RCSM is valuable in the research of EDWA.
Mechanism of enhanced convective heat transfer coefficient of nanofluids
Authors: Xie Hua-Qing  , Chen Li-Fei  ,   上海第二工业大学城市建设与环境工程学院，上海  201209
Published: December 2020

Nanofluids have enhanced heat transfer capacity compared to conventional fluids. In the present paper, the effects of the thermophysical properties and thermal dispersion on the convective heat transfer coefficients of nanofluids have been investigated. The analytical results show that the effective thermal conductivities of a nanofluid is enhanced with the addition of nanopaticles into the base fluid. The collisions between nanoparticles, fluid molecules, and the wall of flow-tube are intensified, leading to enhanced mixing agitation and turbulence. Improved thermophysical properties and thermal dispersion result in the convective heat transfer coefficient enhancement of nanofluids.
Correlations between viscosity and glass-forming ability in bulk amorphous alloys
Authors: Wei Hong-Qing  , Li Xiang-An  , Long Zhi-Lin  , Peng Jian  , Zhang Ping  , Zhang Zhi-Chun  ,   (1)湘潭大学土木工程与力学学院，湘潭  411105; (2)湘潭大学土木工程与力学学院，湘潭  411105；邵阳学院机械与能源工程系，邵阳  422000
Published: December 2020

According to the classical crystallization theory, the influences of kinetics and thermodynamics on glassforming ability （GFA） for bulk metallic glasses has been investigated. The theoretical analysis shows that crystallization resistance is in proportion to the viscosity of “nose” temperature （Tn） while crystallization driving force is inversely proportional to the viscosity of crystallization onset temperature （Tx） on reheating in timetemperaturetransformation （TTT） curve, and therefore a GFA parameter ω0, defined as （Tg-T0）/（Tx-T0）-（Tg-T0）/（Tn-T0）, was proposed （wherein Tg and T0 are glass transition temperature and Vogel temperature respectively）. The parameter ω0 shows an excellent correlation with the critical cooling rate for glass formation of bulk metallic glasses, with the statistical correlation factor of R2=09626. Furthermore, the relationships between the GFA and Trg, ΔTx, γ, γm, ΔTrg, α, β, δ and φ, as well as the fragility of liquid could be explained reasonably based on our proposed ω0 parameter.
The structure study for Si80 cages
Authors: Wang Lei  , Yang De-Ren  ,   浙江大学材料科学与工程系，硅材料国家重点实验室，杭州  310027
Published: December 2020

The structure study for large Si80 cages using ab initio calculations based on density functional theory is reported. The results show that Si cages are distorted from perfect Ih symmetry to Th symmetry. The geometry and electronic properties of Si80 cages are discussed.
Elastic constants, electronic structure and optical properties of solid krypton under pressure by first-principles calculations
Authors: Li Xiao-Feng  , Ji Guang-Fu  , Peng Wei-Min  , Shen Xiao-Meng  , Zhao Feng  ,   (1)洛阳师范学院物理与电子信息学院，洛阳  471022; (2)上海交通大学材料科学与工程学院，上海  200240; (3)中国工程物理研究院流体物理研究所冲击波物理与爆轰物理重点实验室，绵阳  621900; (4)中国工程物理研究院流体物理研究所冲击波物理与爆轰物理重点实验室，绵阳  621900；洛阳师范学院物理与电子信息学院，洛阳  471022；四川大学物理科学与技术学院，成都  610065
Published: December 2020

The elastic constants, electronic structure and optical properties of solid krypton are investigated by first-principles plane-wave pseudo-potential method in the scheme of density functional theory within local density approximation and generalized gradient approximation. The calculated elastic constants under pressure are in good agreement with the experimental and theoretical data. The obtained Debye temperature and sound velocity increase with pressure. The electronic structure and optical properties under pressure are also predicted, the energy band gap decreases, optical absorption coefficient increases and absorption peak widens under pressure. This leads to easy electron transition and solid krypton probably becomes semiconductor.
Non-Noether conserved quantities for nonholonomic controllable mechanical systems with relativistic rotational variable mass
Authors: Xia Li-Li  , Li Yuan-Cheng  , Wang Xian-Jun  ,   (1)河南教育学院物理系,郑州  450014; (2)中国石油大学(华东)物理科学与技术学院,东营  257061
Published: December 2020

The non-Noether conserved quantities (the Hojman conserved quantity) for nonholonomic controllable mechanical systems with relativistic rotational variable mass are discussed. The differential equations of motion of the systems are established. The definition and criterion of the Mei symmetries and the Lie symmetries of the system are discussed respectively. The necessary and sufficient condition under which the Mei symmetry is Lie symmetry is presented. The condition under which a non-Noether conserved quantity can be induced by the Mei symmetries and the form of the conserved quantity are obtained. An example is presented to illustrate the application of the result.
Effects of time period modulation of the noise correlation intensity and bias signal modulation of the noise on stochastic resonance of a single-mode laser
Authors: Chen De-Yi  , Wang Zhong-Long  ,   三峡大学理学院物理系，宜昌  443002
Published: December 2020

In the case of the noises modulated by the bias signal, the stochastic resonance of a single-mode laser driven by two colored noises with time period modulation correlation intensity is investigated. By means of the linear approximation method, we calculate the output signal to-noise ratio. The evolution of the output signal to-noise ratio with the self-correlation time of the noises and noise intensity and bias signal is discussed. It is found that the evolution of the output signal to-noise ratio with the pump noise intensity and self-correlation time presents the stochastic resonance. The peak of the stochastic resonance is decreased by the bias signal. Thus we should control the intensity of the bias signal in practice.
Initial condition estimate of coupled map lattices system based on symbolic dynamics
Authors: Shen Min-Fen  , Lin Lan-Xin  , Li Xiao-Yan  , Chang Chun-Qi  ,   (1)汕头大学工学院，汕头  515063; (2)汕头大学工学院，汕头  515063；香港大学电子工程系，香港; (3)香港大学电子工程系，香港
Published: December 2020

The initial condition estimate of local coupled map lattice system based on given symbolic sequence is researched. The relationships be tween the parameter of coupling strength, the map function and the performance of estimating initial condition are analyzed. It is proved that any value taken from the phase-space IM does not necessarily converge to the initial vector. There is a direct relationship between convergence property and coupling strength. Moreover, the performances of estimating initial vector are different according to different map functions. The simulation results are completely consistent with theoretical analysis, which shows that the proposed arithmetic for estimating initial vector of coupled map lattice system is correct. The inverse process of coupled map lattice system is fully investigated and the simulation results in this paper provide a theoretical and factual basis for better analysis and description of the physical process of the actual model.
Complicated oscillations in coupled electrical circuits
Authors: Zhang Xiao-Fang  , Chen Zhang-Yao  , Bi Qin-Sheng  ,   江苏大学理学院，镇江  212013
Published: December 2020

The dynamical evolution process of the coupled system connecting two nonlinear electrical circuits with suitable circuit is investigated. The bifurcation behavior as well as the ways to chaos of the two subsystems is presented. It is pointed out when both of the two subsystems behave as periodic, the coupled system may also be led to chaos via cascading of period-doubling bifurcations. Meanwhile, in the chaotic region, critical increase of period as well as period-adding bifurcation can be observed. As to the interaction between periodic movement and the chaotic oscillation, the original periodic subsystem may chaotically oscillate around the original orbit. The amplitude associated with the oscillation increases rapidly, resulting in the obvious chaotic characteristics. On the contrary, the periodic subsystem may not only cause the instability of the chaotic subsystem, but also lead to change of the chaotic structures.
Paired behavior effect on pedestrian evacuation dynamics
Authors: Zhou Jin-Wang  , Kuang Hua  , Liu Mu-Ren  , Kong Ling-Jiang  ,   (1)广西师范大学物理与电子工程学院，桂林  541004; (2)广西师范大学物理与电子工程学院，桂林  541004；上海大学上海市应用数学和力学研究所，上海  200072
Published: December 2020

Gathered movement follow with the group is a common behavior among familiar pedestrians. In order to study such behavior acts on the impact of the evacuation process, we proposed a new cellular automaton evacuation model which taking into account side-by-side in paired, front-behind in paired, and mixed paired, studied the influence of evacuation among the three paired pattern and compared each other under different parameters.
Modeling urban expressway systems with ramps and accessory roads by cellular automaton model
Authors: Mei Chao-Qun  , Huang Hai-Jun  , Tang Tie-Qiao  ,   (1)北京航空航天大学交通科学与工程学院，北京  100083; (2)北京航空航天大学经济管理学院，北京  100083; (3)北京航空航天大学经济管理学院，北京  100083；首都经济贸易大学统计学院，北京  100070
Published: December 2020

In this paper, a cellular automaton model is proposed to study the traffic of urban expressway systems with on-off-ramps and accessory roads. Three lane changing rules are defined for different road sections. Simulation results show that higher on-ramp rate easily produces traffic jams on main roads, on-ramps and their upstream sections. Higher off-ramp rate easily leads to conflict with the inflow of accessory road. The system having two lanes on main and accessory roads can alleviate the jam degree and decrease the vehicles' running time when on-ramp rates are high.
Recursive implementation of Gaussian pulse shaping based on wavelet analysis
Authors: Chen Shi-Guo  , Ji Shi-Yin  , Liu Wan-Song  , Song Ze-Yun  , Pang Li-Jun  ,   (1)贵州师范大学物理与电子科学学院，贵阳  550001; (2)黔南民族师范学院物理与电子科学系，都匀  558000
Published: December 2020

Gaussian pulse shaping filter of exponential decay signal based on wavelet analysis can be more described by using linear combination of both Gaussian function and its first order derivative. On the basis of the recursive approximate algorithm of Gaussian function and its derivative, the recursive approximate algorithm of Gaussian pulse shaping of exponential decay signal based on wavelet analysis is studied. The experiment results with simulating and sampling signals show that the recursive approximate Gaussian pulse shaping is well accorded with the direct convolution of the Gaussian pulse shaping. The characteristic of the Gaussian pulse shaping based on wavelet analysis is well exhibited by the recursive approximate Gaussian pulse shaping. The obtained result can serve as the digital algorithmic base for studying the realization of the Gaussian pulse shaping in digital chip.
Structure and potential energy function of the ground state of OH（D） and SH（D）
Authors: Zhu Ji-Liang  , Ren Ting-Qi  , Wang Qing-Mei  ,   曲阜师范大学物理工程学院,曲阜  273165
Published: December 2020

The structure and dissociation energy of the ground state of OH and SH are calculated using QCISD（T）/6-311++G（3df,2pd） method and QCISD（T）/ 6-311++G（3df,2pd）. Based on the theory of atomic and molecular statics, the reasonable dissociation limit for the ground state （X2Π） of OH is derived. The potential energy curve and relevant optical constants of this state are obtained by least square fitting to the Murrell-Sorbie function. All calculation results are in good agreement with the experimental data.
Physical properties of laser-electron Compton scattering
Authors: Ge Yu-Cheng  ,   北京大学物理学院和核物理与核技术国家重点实验室，北京  100871
Published: December 2020

The energy properties and the differential cross-sections of laser-electron-Compton scattering are quantitatively investigated. The calculations show simple structures of the scattered photon energy and the angular distribution of the differential cross-section. At high incident electron energy, Compton scattering X-ray source has features of easily tunable photon energy and small forward emission angle. Although the dispersion of Compton scattering X-ray source is large, narrow bandwidth X-ray emission can be obtained experimentally by using specific monochromatic filter. The total cross-section and the cross-section within the forward emission angle （γ, where γ= E/m0c2 is the total electron energy （E） in the unit of its static energy （m0c2）） change slightly for different laser wave lengths and different incident electron energies in a broad range from 1 MeV to 10 GeV. They have values of 0067 mb and 0033 mb, respectively. The total cross-section of the visible lights is very small. These results may be useful for building new generation ultra-short X-ray source based on Compton scattering technique.
Optimization of optoelectronic reconstruction of phase hologram by use of digital blazed grating
Authors: Yu Ying-Jie  , Wang Tao  , Zheng Hua-Dong  ,   上海大学精密机械工程系，上海  200072
Published: December 2020

The utilization efficiency of light energy is affected by the multi-order images during the reconstruction of holograms based on liquid crystal spatial light modulator （LC-SLM）, which leads to the low intensity of single image. A novel method is proposed to improve the diffraction efficiency of single reconstructed image by synthesizing phase hologram and digital blazed grating. The property and principle of wave-front modulation are analyzed by use of digital blazed grating as diffractive optical element （DOE）. The effect of digital blazed grating on the reconstructed image of phase hologram by use of LC-SLM is also described. Holographic optoelectronic display system based on LC-SLM is set up for phase hologram reconstruction. Theoretical analysis shows that, the intensity of single reconstructed image is increased by 1302 per cent by adding digital blazed grating with period of 2 pixels in vertical or horizontal direction, and 4297 per cent with the same period of digital blazed grating in vertical & horizontal directions. The experimental result also verifies that, by the proposed method, the energy intensity of single reconstructed image is increased and the utilization efficiency of light energy is improved.
Density functional theory study of rhodium adsorption on single-wall carbon nanotubes
Authors: Yang Pei-Fang  , Hu Juan-Mei  , Teng Bo-Tao  , Wu Feng-Min  , Jiang Shi-Yu  ,   (1)浙江师范大学化学与生命科学学院,金华  321004; (2)浙江师范大学凝聚态物理研究所,金华  321004
Published: December 2020

Rhodium adsorption on （6, 6） single-walled carbon nanotubes （SWCNTs） was systematically investigated by density functional theory （DFT）. According to the analysis of adsorption configurations and adsorption energies, it is found that the most stable configurations are I-H1, I-H2, O-H1, O-H2 and O-B1. The adsorption energy of O-H2 is -2.29?eV, which is 0.49?eV higher than that of I-H2. This might be attributed to the graphite's winding effect, which the well-proportioned charge density on the graphite redistributes during the formation process of SWCNTs and then induces more charge to the outside of SWCNTs than the inside. Based on the partial density of states （PDOS） and Mulliken charge analysis, it is found that 5s electrons of Rh transfer to 4d orbit, while 4d electrons transfer to SWCNTs. Therefore, the Rh atom is positively charged, while the （6, 6） SWCNTs is negatively charged. Combining the PDOS calculations with the band structure results, the magnetism of Rh adsorbed outside of SWCNTs is higher than that inside SWCNTs.
The geometrical structure, electronic structure and magnetism of bimetallic AunM2 （n=1,2; M=Sc, Ti, V, Cr, Mn, Fe, Co, Ni） clusters
Authors: Gu Juan  , Wang Shan-Ying  , Gou Bing-Cong  ,   (1)北京理工大学理学院，北京  100081; (2)北京理工大学理学院，北京  100081；清华大学物理系，北京  100084; (3)清华大学物理系，北京  100084
Published: December 2020

The geometrical structure, stability, electronic structure and magnetism of bimetallic clusters AuM2 and Au2M2, where M is 3d transition metal element, are investigated systematically by using the first-principles method based on density functional theory. In contrast to semiconductor clusters, the bimetallic clusters consisting of Au and transition metal elements usually form a large number of low-energy isomers, some of which are very similar in structure. Similar to the pure transition metal cluster, AuM2 and Au2M2 clusters also display dramatic magnetism. The magnetic moment of transition metal element in AuM2 and Au2M2 clusters is either enhanced or weakened with respect to the bulk value, which is closely dependent on the orbital splitting. For the ground state, the magnetic moments of two transition metal elements in AuCr2, Au2Cr2 and Au2Mn2 clusters are anti-parallel, and those in other clusters are parallel.
Preparation and electrical properties of the novel mixed ionic-electronic conductors Sm0.9Ca0.1Al1-xMnxO3
Authors: Xiang Jun  , Wei Ting  , Peng Tian-Gui  , Zhang Yu  , Lou Ke-Xing  , Shen Xiang-Qian  ,   (1)江苏大学材料科学与工程学院,镇江  212013; (2)江苏科技大学数理学院,镇江  212003; (3)江苏科技大学数理学院,镇江  212003；江苏大学材料科学与工程学院,镇江  212013
Published: December 2020

The novel mixed ionic-electronic conductors Sm0.9Ca0.1Al1-xMnxO3 （SCAM, x= 0.1—0.5） were prepared by the organic gel method combined with solid state sintering technology. The thermal decomposition and phase inversion process of the gel precursors, crystal strucutres and phase stability of the sinters were studied by using thermogravimetric and differential thermal analysis （TG-DTA） and X-ray diffraction. The electrical conductivities of sintered ceramics in both air and 5%H2/Ar were measured by the direct current four-wire method. The experimental results show that the well-crystallized nanopowders with tetragonal perovskite structure can be obtained after calcining the gel precursors at 900℃ for 5h, the phase stability of SCAM ceramics decreases with increasing Mn content under reduction atmosphere. The electrical conductivity of SCAM ceramics is dominated by p-type electronic conduction and increases with Mn content and temperature. The mechanism of electronic transport is the hopping of p-type small polaron. With increasing calcination temperature and prolonging holding time, both the electrical conductivity and relative density of SCAM9155 become large initially and then decrease. The SCAM9155 sample sintered at 1600℃ for 10h has the highest relative density of 98.2% and electrical conductivity reaching 7.30S/cm in air and 1.91S/cm in 5%H2/Ar at 850℃. The apparent activation energies for SCAM9155 in air and in 5%H2/Ar were calculated to be 0.273 and 0.371eV, respectively. The Ca- and Mn-substituted SmAlO3 with relatively high conductivity may be used as a potential anode material for solid oxide full cells （SOFCs）.
Experimental and theoretical study of blue InGaN/GaN multiple quantum well blue light-emitting diodes
Authors: Li Wei-Jun  , Zhang Bo  , Xu Wen-Lan  , Lu Wei  ,   (1)华东师范大学信息科学技术学院,上海  200062; (2)中国科学院上海技术物理研究所，红外物理国家重点实验室，上海  200083
Published: December 2020

A 2D simulation of electrical and optical characteristics of InGaN/GaN multiple quantum well blue light-emitting diodes by APSYS software with a dot-well model and well model are investigated. It shows that I-V and electrical luminescence simulation results based on the quantum dot model are in better agreement with the experimental data than that based purely on quantum well model. Moreover, simulation result also suggest that the non-equilibrium quantum transport plays an important role in the InGaN/GaN multiple quantum well light-emitting diodes.
Influence of fabrication technique on structure and photoluminescence of Zn1-xMgxO thin films
Authors: Wang Wei-Na  , Fang Qing-Qing  , Zhou Jun  , Wang Sheng-Nan  , Yan Fang-Liang  , Liu Yan-Mei  , Li Yan  , Lü Qing-Rong  ,   安徽大学物理与材料科学学院，光电信息获取与控制教育部重点实验室，合肥  230039
Published: December 2020

Single-crystalline Zn1-xMgxO thin films with c-axis orientation have been deposited on Si（100） substrate by pulsed lser deposition. The effect of the thickness, Mg content, annealing temperature and oxygen atmosphere on the structure, morphology and photoluminescence of the Zn1-xMgxO thin films are studied by X-ray diffraction,atomic force microscopy,scanning electron microscopy and photoluminescence spectra. The results indicate that the hexagonal wurtzite type of Zn1-xMgxO can be stabilized up to Mg content xx≤0.35.The grain size of the samples increased by the post_annealing, and the structure of the Zn0.75Mg0.25O film changed from cubic to hexagonal wurtzite type when annealed at 600℃. An appropriate oxygen pressure can reduce both the number of defects and the c-axis stress. But superfluous oxygen is apt to combine with Mg and hinders the growth of hexagonal wurtzite type ZnO. Photoluminescence spectrum indicates that the defect_level peak is mainly related with the zinc vacancy, substitutional O on the zinc site （OZn） and interstitial oxygen vacancies （Oi）, and the ultraviolet emission peak has a blue shift due to annealing.
An analytical solution for two-dimensional uniform currents on linear surface capillary-gravity short-crested waves
Authors: Huang Hu  ,   上海大学上海市应用数学和力学研究所，上海  200072
Published: December 2020

By considering the effect of two-dimensional uniform currents, a solution for linear surface capillary-gravity short-crested waves in water of finite depth is obtained. Both a generalized Doppler-shift relation and a generalized dispersion relation are first found, and the generalized intrinsic frequency with variety in dual values is directly correlated with the uniform currents.
Two-level model of light propagation in photonic lattices and nonlinear Landau-Zener tunneling
Authors: Wang Sha  , Yang Zhi-An  ,   济南大学理学院，济南  250022
Published: December 2020

We deduce a two-level model of light propagating in photonic lattices of Kerr medium and two kinds of saturated photorefractive medium,establish the classical Hamiltonian system, study the evolution of the phase-space motion of the Hamiltonian system for one kind of saturated photorefractive medium, namely, the Screening medium, and then study the nonlinear Landau-Zener tunneling numerically. Results show that the tunneling probability is enhanced when the nonlinearity is positive while it is restrained when the nonlinearity is negative.
The largest Lyapunov prediction method for the end issue of empirical mode decomposition
Authors: Yang Yong-Feng  , Wu Ya-Feng  , Ren Xing-Min  , Qin Wei-Yang  , Zhi Xi-Zhe  , Qiu Yan  ,   西北工业大学振动工程研究所，西安  710072
Published: December 2020

The largest Lyapunov prediction method for dealing with the end issue of empirical mode decomposition （EMD） is proposed. Generally，the largest Lyapunov prediction method extends the time series near both ends of the data. After the extension，the spline does not swing at both ends of the data. Because the intrinsic characteristics of the signal are considered, the end issue becomes more reasonable. The simulation results proved that the new method can be used to solve the end issue effectively.
The mathematical description of uniformity and its relationship with chaos
Authors: Luo Chuan-Wen  ,   东北林业大学均匀度理论及应用研究中心，哈尔滨  150040
Published: December 2020

Based on the definition of monopolized sphere，instantaneous chaometry and k step chaometry are defined，which are the stable characteristic of chaotic orbit. Uniform index is defined by monopolized sphere，and its description of uniformity is quite consistent with peoples understanding. The contained uniform index，which is a transitionary concept，is similar to uniform index and has good mathematical property. For random orbit，the contained uniform index converges to 1/Vn（1）（Vn（1） is the volume of the sphere with radius 1），when the point number of an orbit is great enough，uniform index is approximately equal to the contained uniform index. Only by properly selecting the polyhedron containing the basin of attraction of a discrete dynamic system，the ratio of instantaneous chaometry and uniform index is constant. The application of uniform index on Logistic map shows that as the parameter of Logistic map r increases, the orbits are more and more uniform but the expectation uniform index will be less than 0.5，which is that of random orbit，so asymptotical periodic orbit and random pattern are the two extreme status of chaotic orbits.
Wavelength division multiplexing of chaotic optical communication and OC-48 fiber communication
Authors: Zhang Jian-Zhong  , Wang An-Bang  , Wang Yun-Cai  ,   太原理工大学理学院物理系，太原  030024
Published: December 2020

Wavelength division multiplexing transmission of chaotic optical communication and current optical communication is numerically confirmed and analysed. For a 100 GHz channel span，a 1-Gbit/s digital message extraction is achieved in chaotic optical communication system and a 2.5-Gbit/s digital signal is received in current optical communication system. The results show that when the peak power of digital signal in current optical communication is less than 17 dBm，chaotic optical communication can realise parallel transmission of 80 km. In addition，when the peak power of digital signal in current optical communication is 7 dBm，the quality of the received signal in current optical communication is hardly interfered by signals of chaotic optical communication. As the transmission distance increases from 80 km to 160 km，the opening of the corresponding eye diagram decreases from 82% to 70%.
Demodulation method for second harmonic signal in optical fiber gas sensor
Authors: Li Zheng-Ying  , Wang Hong-Hai  , Jiang Ning  , Cheng Song-Lin  , Zhao Lei  , Yu Xin  ,   武汉理工大学光纤传感技术与信息处理教育部重点实验室，武汉  430070
Published: December 2020

The measurement sensitivity can be greatly improved when tunable laser spectroscopy together with the method of wavelength modulation of second harmonic detection is used to measure the gas density. However, light transfer and circuit delay will lead to unknown phase delay. The measurement results of second harmonic signal will be seriously influenced by the phase change of the frequency-doubled reference signal relative to the measured signals containing information of gas density. A four-channel multiplier demodulation circuit is designed here. Sinusoidal signals and cosine signals are used to demodulate measured signals. Then two demodulated signals appear relating to the phase difference of sinusoidal value and cosine values after the measured signals pass the integral circuit. The amplitude signals can be obtained, which have no relation with the phase difference when demodulated signals are squared through the adder and the phase difference is eliminated. Experiment shows that the stability of the measured results in the system has been improved greatly if the obtained second harmonic signal keeps stable when the phases change from 0° to 90°.
The relationship between resonant frequency band and cell size in left-handed materials
Authors: Wu Jun-Fang  , Sun Ming-Zhao  , Zhang Chun-Min  ,   (1)西安工程大学理学院，西安  710048；西安交通大学理学院，西安  710049; (2)西安交通大学理学院，西安  710049
Published: December 2020

By now, the negative refraction phenomenon occurs only in the microwave band in the left-handed materials, and this frequency band is called resonant frequency band. The application of the left-handed materials is greatly limited because the resonant frequency is low, and the source of wave is usually sun light or visible light.How to shift the resonant frequency from low frequency to high frequency, even to the visible light band, is an important and urgent research problem. Many parameters of the periodic structures will greatly affect the resonant frequency, including the shapes and sizes. The resonant frequency is shifted by adjusting the cell size.The relation that the resonant frequency band can be shifted and broadened from low frequency to high frequency with the reducing cell size, is obtained by simulation and experiment.
Theoretical study on stimulated-Brillouin-scattering gain-spectrum broadening and pulse-distortion reduction of slow-light propagation using double broadband pump in optical fibers
Authors: Wang Shi-He  , Ren Li-Yong  , Liu Yu  ,   (1)中国科学院西安光学精密机械研究所瞬态光学与光子技术国家重点实验室,西安  710119; (2)中国科学院西安光学精密机械研究所瞬态光学与光子技术国家重点实验室,西安  710119；中国科学院研究生院,北京  100049
Published: December 2020

We analyse the stimulated Brillouin scattering （SBS） slow light using double broadband pumps in a single mode fiber. A new SBS gain spectrum tailoring method is proposed using two Gaussian-shaped broadband pumps with different powers and spectral widths, and the central frequency interval of them is carefully set at two Brillouin frequency shifts to make sure that the gain of one pump has the same center with the loss of the other. The top of the gain spectrum of the strong pump beam can be counteracted by the loss spectrum of the weak pump beam to construct a flat top gain spectrum. We give the optimized conditions of the laser powers and spectral widths between two broadband pumps to obtain a flat gain. Distortions of signal pulse under this flat top gain are studied and compared with that obtained using a single broadband pump. We find that the flat top gain profile can effectively reduce the pulse distortions.
Fiber grating sensor demodulation method based on polarization interference
Authors: Zhang Jin-Long  , Yu Chong-Xiu  , Wang Kui-Ru  , Zhao De-Xin  , Lin Mei-Mei  , Li Cheng  ,   (1)北京邮电大学电子工程学院,北京  100876; (2)北京邮电大学电子工程学院,北京  100876；河南大学物理与电子学院,开封  475001
Published: December 2020

A novel wavelength shift detection scheme for use in fiber Bragg grating sensing systems is proposed. The structure of the polarization maintaining fiber loop mirror is studied and its theoretical model is established. In addition, the distribution characteristics of the input light wavelength and the output power are analysed. Moreover, numerical simulation and experimental validation are also performed. The results show that the device has simple structure, high stability and high detection precision. The measuring range and the precision can be adjusted by varying the parameters of the fiber loop mirror. In the demodulation range larger than 1 nm, the average precision of the wavelength demodulation is lower than 1 pm.
Analysis of magneto-mechano-electronic coupling factors in magnetostrictive/piezoelectric laminated composite
Authors: Bian Lei-Xiang  , Wen Yu-Mei  , Li Ping  ,   重庆大学光电工程学院，光电技术及系统教育部重点实验室，重庆  400044
Published: December 2020

The magneto-mechanical coupling factor, electromechanical coupling factor, and magnetoelectric （ME） coupling factor of magnetostrictive/piezoelectric laminated composite, which are related to the geometric dimensions and the performance parameter of the magnetostrictive and piezoelectric materials, are analysed and derived. It is also demonstrated that the ME voltage coefficient at low frequency is directly proportional to the ME coupling factor while the ME voltage coefficient at resonance is directly proportional to the product of the ME coupling factor and the effective mechanical quality factor of the composite. In addition, the ME voltage coefficient is related to the intrinsic impedance of the composite. Multiple composites of distinct magnetostrictive materials （Terfenol-D, FeNi-based-alloy） and piezoelectric materials （PZT5-H, PZT8） are further analysed to demonstrate the theoretical analysis. The Terfenol-D/PZT5-H and FeNi-based-alloy/PZT8 laminated composites are fabricated and investigated, and the analysis gives better explanations to the experimental results.
Building and analysis of properties of a class of correlative and switchable hyperchaotic system
Authors: Liu Yang-Zheng  , Jiang Chang-Sheng  ,   (1)南京航空航天大学自动化学院,南京  210016; (2)南京航空航天大学自动化学院,南京  210016；南京工程学院非线性物理研究所，南京  211167
Published: December 2020

A class of four-dimensional correlative and switchable hyperchaotic systems are built by adding an additional state, the nonlinear functions and anti-control into the three-dimensional chaotic system. Some of their basic properties are studied, such as the feature of equilibrium, the phase portraits of hyperchaotic attractor, Lyapunov exponent and the evolution of the dynamical action. The practical circuit is designed to realise these systems.
A new three-dimensional chaotic system and its circuit simulation
Authors: Tang Liang-Rui  , Li Jing  , Fan Bing  , Zhai Ming-Yue  ,   华北电力大学电气与电子工程学院，北京  102206
Published: December 2020

A new three-dimensional chaotic system is reported in this paper, which is different from the Lorenz and Chen systems. This new system contains five system parameters and two quadratic cross-product terms. The basic dynamic properties of the new system are investigated via theoretical analysis, numerical simulation, Lyapunov exponent spectrum, bifurcation diagrams, Lyapunov dimension and Poincare diagrams. The different dynamic behaviors of the new system are analyzed when each system parameter is changed. Finally, the chaotic circuit is designed and realized by the Multisim software. It confirms that the chaotic system can be achieved.
Zero range process condensation based on preferential aggregate mechanism in scale free networks
Authors: Ma Li-Juan  , Tang Ming  , Liang Xiao-Ming  ,   (1)华东师范大学理论物理研究所，上海  200062; (2)郑州铁路职业技术学院,郑州  450052
Published: December 2020

In the real world, condensation based on preferential aggregate mechanism, such as migration-driven aggregate growth system and packets routing in complex networks, is an important phenomenon. The research studies the ZRP condensation based on preferential aggregate mechanism in sale-free networks, in order to understand how the weighted transport with preferential hopping rates influences real systems. Instead of the approach of grand canonical ensemble which is generally used in a zero range process, an alternate approach of the mean field equations is used to study the dynamics of ZRP. The research finds that there are three phases when preferential aggregate index is greater than zero: namely the complete condensation, partial condensation, and well-proportioned condensation. But the ZRP system has only two phases when the preferential aggregate index is smaller than zero:the partial condensation and well-proportioned condensation. On the other hand, the mean particle distribution in the stationary state depends on the jumping rate, link weight, and preferential aggregate indexes. Monte Carlo simulation also validates the analytical results.
Performance analysis of the substrate-free focal plane array in infrared imaging
Authors: Cheng Teng  , Zhang Qing-Chuan  , Chen Da-Peng  , Wu Xiao-Ping  , Shi Hai-Tao  , Gao Jie  ,   (1)中国科学技术大学中国科学院材料力学行为和设计重点实验室，合肥  230027; (2)中国科学院微电子研究所，北京  100029
Published: December 2020

Based on the proposed optical readout uncooled infrared (IR) imaging system，several batches of the substrate-free focal plane array (FPA) with different pitches have been successively fabricated，and by using these fabricated FPAs，the thermal images were obtained at room temperature. However，the theoretical analysis indicates that the deviation between the theoretical model assuming constant temperature of the supporting frames of the FPAs and the experimental results gradually increases with the decreasing pitch size of from 200μm to 60μm. Based on the finite element method，the thermal characteristic of those FPAs was simulated and the reason for the deviation is found to be that the temperature-constant assumption is not quite appropriate for the substrate-free FPA，and the absorption of the thermal radiation will obviously result in the temperature rise of the supporting frame，which would increase the temperature of the adjacent pixels. The imaging performance of the substrate-free FPA is also analyzed. Compared with the substrate FPA with the same pitch, the thermal detection sensitivity of the substrate-free FPA with 60μm pitch increases by about one order of magnitude.
Theoretial analysis on extending the field-of-view of the imaging spectrometer based on combined Wollaston prisms
Authors: Wu Hai-Ying  , Zhang Chun-Min  , Zhao Bao-Chang  ,   (1)西安交通大学理学院，西安  710049; (2)中国科学院西安光学精密机械研究所空间光学实验室，西安  710049
Published: December 2020

The principle of beam splitting of spectrometer based on the combination of two Wollaston prisms and a half-wave plate is presented. The propagation track of light wave in the combination is analysed by wave normal-tracing method at random incidence angle and the formulas of the path difference between the e and o wave normal are deduced. Computer simulations are carried out to explain why the combination can increase the field of view of spectrometer. The results will provide a very important theoretical basis for the study of polarization interference imaging spectrum technology and the development of static large field of view polarization interference imaging spectrometer developed by us.
Theoretical and experimental investigation of optical bistability in end-pumped Tm，Ho：YLF lasers
Authors: Zhang Xin-Lu  , Wang Yue-Zhu  , Li Li  , Ju You-Lun  , Jiang Bo  ,   (1)哈尔滨工程大学理学院，哈尔滨  150001; (2)哈尔滨工业大学光电技术研究所可调谐激光国家重点实验室，哈尔滨  150001
Published: December 2020

We demonstrate the strong optical bistability of a 2μm continuous wave Tm，Ho：YLF laser end pumped by a 792nm fiber-coupled laser diode. The quasi-three-level rate equation theoretical model is given under consideration of the energy transfer upconversion and ground state reabsorption effects. The bistable output of Tm，Ho：YLF laser is predicted theoretically by solving the coupled rate equations and the mechanism of the bistability output is analyzed. The bistable output is also studied experimentally. When the laser crystal is at 253K，the width of the bistable region is 1.6W and the jump power at the tujump point is 82.5mW. The theoretical results are in agreement with the experimental results，showing that the theoretical model is reasonable.
A high power quasi-continuous-wave yellow laser based on intracavity sum-frequency generation
Authors: Lu Yuan-Fu  , Xie Shi-Yong  , Bo Yong  , Cui Qian-Jin  , Zong Nan  , Gao Hong-Wei  , Peng Qin-Jun  , Cui Da-Fu  , Xu Zu-Yan  ,   (1)中国科学院物理研究所北京凝聚态物理国家实验室，北京  100190; (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  100190；中国科学院研究生院，北京  100049
Published: December 2020

This paper reports a high-power all-solid-state yellow laser based on intracavity KTP crystal sum-frequency generation. In order to achieve high output power，three key techniques are used：Firstly，the system is designed to operate in a pulsed mode to increase the beam quality and optical-to-optical conversion efficiency under the same pump level. Secondly，thermal near-unstable resonator design and two-rod birefringence compensation is used to acquire large fundamental mode size in Nd：YAG rod. Thirdly，by optimizing an L-shaped co-folding-arm plane-concave symmetrical cavity，the two fundamentals have a high spatial overlap in the sum-frequency crystal and satisfy the power ratio requirement. As a result of the applications of these techniques，a quasi-continuous-wave yellow laser with output power of 7.6W and repitition frequency of 1.1kHz is obtained. To the best of our knowledge，this is the highest yellow laser output power produced by an intracavity sum-frequency Nd：YAG laser.
Woringer-Kolopp Disease of the Foot: A Case Report
Authors: LaPolla James J. , DiDomenico Lawrence A. , Brodell Robert T. , Casteel Michael L.
Published: December 2020

Woringer-Kolopp disease is a rare variant of mycosis fungoides, a type of cutaneous T-cell lymphoma. Described is a case of a small annular plaque on the foot diagnosed histologically as Woringer-Kolopp disease and treated successfully with topical and intralesional steroids. In addition, a brief review of the literature and treatment options is provided.
The Effect of Wound pH on Healing Rates in Chronic Wounds: A Literature Review
Authors: Tarricone Arthur , De La Mata Karla , Rothstein Michael , Soave Ronald L.
Published: December 2020

This literature review sought to evaluate the current state of knowledge and guidelines surrounding the role of pH in the recovery of chronic nonhealing wounds. A systematic review of PubMed examining the relationship between pH and wound healing was completed. Seven sources were retrieved for review. The development of a highly structured and reproducible system of pH-driven therapy may add to the treatment algorithm for chronic nonhealing wounds.
Benign Schwannoma of the Lateral Plantar Nerve: A Case Report
Authors: Hoffler Hayden L. , Steele Rebecca M. , Long Christina S.
Published: December 2020

Schwannomas are benign, encapsulated soft-tissue tumors that rarely present to the foot and ankle. These tumors are usually asymptomatic unless an increase in size or disruption of the nerve causes pain. We report a case of a painful mass along the lateral plantar nerve near the fourth metatarsal base that was surgically excised and confirmed as a benign schwannoma by means of histopathologic analysis. At the final follow-up of over 2 years, the patient reported no pain, neurologic deficits, or signs of recurrence. This case demonstrates an unusual location of a schwannoma arising from the lateral plantar nerve.
A positive feedback loop between Flower and PI(4,5)P2 at periactive zones controls bulk endocytosis in Drosophila
Authors: Li Tsai-Ning , Chen Yu-Jung , Lu Ting-Yi , Wang You-Tung , Lin Hsin-Chieh , Yao Chi-Kuang
Published: December 2020

Synaptic vesicle (SV) endocytosis is coupled to exocytosis to maintain SV pool size and thus neurotransmitter release. Intense stimulation induces activity-dependent bulk endocytosis (ADBE) to recapture large quantities of SV constituents in large endosomes from which SVs reform. How these consecutive processes are spatiotemporally coordinated remains unknown. Here, we show that Flower Ca2+channel-dependent phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) compartmentalization governs control of these processes inDrosophila. Strong stimuli trigger PI(4,5)P2microdomain formation at periactive zones. Upon exocytosis, Flower translocates from SVs to periactive zones, where it increases PI(4,5)P2levels via Ca2+influxes. Remarkably, PI(4,5)P2directly enhances Flower channel activity, thereby establishing a positive feedback loop for PI(4,5)P2microdomain compartmentalization. PI(4,5)P2microdomains drive ADBE and SV reformation from bulk endosomes. PI(4,5)P2further retrieves Flower to bulk endosomes, terminating endocytosis. We propose that the interplay between Flower and PI(4,5)P2is the crucial spatiotemporal cue that couples exocytosis to ADBE and subsequent SV reformation.
Cell non-autonomous regulation of health and longevity
Authors: Miller Hillary A , Dean Elizabeth S , Pletcher Scott D , Leiser Scott F
Published: December 2020

As the demographics of the modern world skew older, understanding and mitigating the effects of aging is increasingly important within biomedical research. Recent studies in model organisms demonstrate that the aging process is frequently modified by an organism’s ability to perceive and respond to changes in its environment. Many well-studied pathways that influence aging involve sensory cells, frequently neurons, that signal to peripheral tissues and promote survival during the presence of stress. Importantly, this activation of stress response pathways is often sufficient to improve health and longevity even in the absence of stress. Here, we review the current landscape of research highlighting the importance of cell non-autonomous signaling in modulating aging fromC. elegansto mammals. We also discuss emerging concepts including retrograde signaling, approaches to mapping these networks, and development of potential therapeutics.
miR-21 is upregulated, promoting fibrosis and blocking G2/M in irradiated rat cardiac fibroblasts
Authors: Guo Huan , Zhao Xinke , Su Haixiang , Ma Chengxu , Liu Kai , Kong Shanshan , Liu Kedan , Li Haining , Chang Juan , Wang Tao , Guo Hongyun , Wei Huiping , Fu Zhaoyuan , Lv Xinfang , Li Yingdong
Published: December 2020

Background

Radiation exposure of the thorax is associated with a greatly increased risk of cardiac morbidity and mortality even after several decades of advancement in the field. Although many studies have demonstrated the damaging influence of ionizing radiation on cardiac fibroblast (CF) structure and function, myocardial fibrosis, the molecular mechanism behind this damage is not well understood. miR-21, a small microRNA, promotes the activation of CFs, leading to cardiac fibrosis. miR-21 is overexpressed after irradiation; however, the relationship between increased miR-21 and myocardial fibrosis after irradiation is unclear. This study was conducted to investigate gene expression after radiation-induced CF damage and the role of miR-21 in this process in rats.

Methods

We sequenced irradiated rat CFs and performed weighted correlation network analysis (WGCNA) combined with differentially expressed gene (DEG) analysis to observe the effect on the expression profile of CF genes after radiation.

Results

DEG analysis showed that the degree of gene changes increased with the radiation dose. WGCNA revealed three module eigengenes (MEs) associated with 8.5-Gy-radiation—the Yellow, Brown, Blue modules. The three module eigengenes were related to apoptosis, G2/M phase, and cell death and S phase, respectively. By blocking with the cardiac fibrosis miRNA miR-21, we found that miR-21 was associated with G2/M blockade in the cell cycle and was mainly involved in regulating extracellular matrix-related genes, including Grem1, Clu, Gdf15, Ccl7, and Cxcl1. Stem-loop quantitative real-time PCR was performed to verify the expression of these genes. Five genes showed higher expression after 8.5 Gy-radiation in CFs. The target genes of miR-21 predicted online were Gdf15 and Rsad2, which showed much higher expression after treatment with antagomir-miR-21 in 8.5-Gy-irradiated CFs. Thus, miR-21 may play the role of fibrosis and G2/M blockade in regulating Grem1, Clu, Gdf15, Ccl7, Cxcl1, and Rsad2 post-irradiation.