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Antimonene-based saturable absorber for a soliton mode-locked and Q-switched fiber laser in the 2 μm wavelength region

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Chinese Physics B 2023年第6期32卷 259-269页

作者： H Ahmad B Nizamani m Z Samion N Yusoff m F Ismail Photonics Research Centre Universiti Malaya50603 Kuala LumpurMalaysia Physics Department Faculty of ScienceUniversiti Malaya50603 Kuala LumpurMalaysia Distinguished Visiting Professor Universiti Kuala Lumpur British Malaysian Institute(UniKL BMI)Batu 8Jln Sungai Pusu53100SelangorMalaysia

we demonstrate antimonene as a saturable absorber(SA) to generate an ultrafast mode-locked and Q-switched laser in the 2 μm wavelength region. The two antimonene-based SAs were prepared and inserted separately in a thulium–holmiumdoped fiber laser to produce the pulsed laser. Antimonene was coated onto a tapered fiber to generate soliton mode-locked pulses and used in thin-film form for the generation of Q-switched pulses. The mode-locking was stable within a pump power of 267 m w–511 m w, and the laser operated at a central wavelength of 1897.4 nm. The mode-locked laser had a pulse width of 1.3 ps and a repetition rate of 12.6 mHz, with a signal-to-noise ratio of 64 d B. Q-switched laser operation was stable at a wavelength of 1890.1 nm within a pump power of 312 m w–381 m w. with the increase in pump power from 312 m w to 381 m w, the repetition rate increased to a maximum of 56.63 k Hz and the pulse width decreased to a minimum value of 2.85 μs. wide-range tunability of the Q-switched laser was also realized within the wavelength range of1882 nm–1936 nm.

关键词： mode-locking Q-switched fiber laser optical saturable absorber

DISLOCATION PINNING IN HIGH TEmPERATURE DEFORmED Ni_3(Al,Ti) SINGLE CRYSTALS CONTAINING DISORDERED γ PRECIPITATES

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Acta metallurgica Sinica(English Letters) 2006年第3期19卷 157-164页

作者： w.H. Tian m. Nemoto Department of materials Physics and Ghemistry University of Science and Technology Beijing Beijing 100083 China Sasebo National Gollege of Technology Okishin 1-1 Sasebo 857-1193 Japan

A transmission electron microscopy （TEm） investigation has been performed on the dislocation pinning in Lie-ordered Ni3（Al, Ti） containing disordered γ *** morphology of deformation induced dislocations in the γ base alloys containing fine dispersion of disordered γ was investigated by means of weak-beam electron microscopy. The superdislocations are strongly attracted to the disordered particles and dissociate on the （111） plane in the γ particles, while they dissociate on the （010） plane in the γ＇ matrix. The disordered γ precipitates play an important role as a pinning point during the cross-slip of superdislocations from （111） to （010） planes in the γ matrix and restrain the cross-slip of superdislocations. The interaction of superdislocations with disordered particles causes the formation of superkinks, jogs and closed loops.

关键词： superdislocation precipitate attractive interaction cross slip Ll2-ordered Ni3Al

Optical nonlinearities of tetracarbonyl-chromium triphenyl phosphine complex

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Chinese Physics B 2017年第4期26卷 214-218页

作者： m D Zidan A w Allaf A Allahham A AL-Zier Department of Physics Atomic Energy CommissionP.O.Box 6091DamascusSyria Department of Chemistry Atomic Energy CommissionP.O.Box 6091DamascusSyria

The new tetracarbonyl - chromium-triphenyl phosphine complex was synthesized and characterized using ultraviolet（UV）-visible,Fourier transform infrared（FTIR）,and nuclear magnetic resonance（NmR） *** characterization results confirm the molecular structure of the new *** z-scan measurements were done by diode laser[continuous wave（Cw）]to estimate the nonlinear optical parameter（X^3）.The results led to calculate three parameters：the groundstate cross sections（σ_g）,the excited-state cross sections（σ_（ex））,and thermo-optic coefficient of the new *** study indicated that our complex is a suitable for photonic applications.

关键词： tetra carbonyl-chromium triphenyl phosphine Z-scan technique nonlinear optical materials

Determination of Traps' Density of State in OLEDs from Current-Voltage Analysis

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Chinese Physics Letters 2016年第1期33卷 127-131页

作者： m.S.Zaini m.A.mohd Sarjidan w.H.Abd.majid Low Dimensional materials Research Centre Physics DepartmentUniversity of Malaya

A simple method to determine the traps＇ density of state （DOS） in organic light-emitting diodes （OLEDs） by manipulating the current-voltage （I-V） characteristic of the devices at room temperature is introduced. In particular, the trap-dependent space-charge limited current formula is simplified to obtain effective density of traps. In this study, poly[（9,9-di-n-octylfluorenyl-2,7-diyl）-alt-（benzo[2,1,3]thiadiazol-4,8-diyl）] （F8BT） and 2- methoxy-5-（3＇, 7＇-dimethyloctyloxy） benzene-l,4-diacetonitrile （0C1 Clo-PPV） are selected as the OLEDs emissive layer. The trap DOS of F8BT- and OC1Clo-PPV-based OLEDs are calculated in the magnitudes of 1024 m^-3 and 1023 m^-3, respectively. In addition, the results agree with the other conventional method which is used to determine the trap DOS in OLEDs. This calculation technique may serve as a robust and reliable approach to obtain the trap DOS in OLEDs at room temperature.

关键词： OLEDs Determination of Traps of in from

DSC study on temperature memory effect of NiTi shape memory alloy

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中国有色金属学会会刊：英文版 2006年第B01期16卷 37-41页

作者： N. LIU w. m. HUANG School of mechanical and Aerospace Engineering Nanyang Technological University Singapore 639798

A systematic study on the temperature memory effect (TmE) in a polycrystalline NiTi shape memory alloy was presented. The investigation was carried out through a series of differential scanning calorimeter (DSC) tests. Two types of tests were conducted, namely single-step test and multi-step test. The influence of the step temperature on the peak/trough temperatures in the subsequent heating process and the associated energy absorption/release in the phase transformations was investigated. Using a simple theoretical model, the exact mechanism behind TmE was studied.

关键词：镍钛合金形状记忆合金温度记忆效应相转变差分扫描量热计

Effect of layer sliding on the interfacial electronic properties of intercalated silicene/indium selenide van der waals heterostructure

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Communications in Theoretical Physics 2022年第3期74卷 112-118页

作者： masood Yousaf m w Younis Ahmed S Jbara m Junaid Iqbal Khan G murtaza m A Saeed Department of Physics Division of Science and TechnologyUniversity of EducationLahore54770Pakistan Department of Chemistry University of Management and TechnologyC-IIJohar TownLahore54770Pakistan mathematics Department College of Education for Pure ScienceAl-Muthanna UniversitySamawah66001Iraq Laboratory of Theoretical and Experimental Physics Department of PhysicsBahauddin Zakariya UniversityMultan60800Pakistan materials modelling Lab Department of PhysicsIslamia College PeshawarKPPakistan Department of mathematics&Natural Sciences Prince Mohammad Bin Fahd UniversityP.O.Box 1664Alkhobar 31952Saudi Arabia

methods capable of tuning the properties of van der waals(vdw)layered materials in a controlled and reversible manner are highly *** electronic properties of two-dimensional vdw heterostructure consisting of silicene and indium selenide(InSe)have been calculated using density functional theory-based computational ***,in order to vary the aforementioned properties,silicene is slid over a InSe layer in the presence of Li *** intercalation of the heterostructure,the buckling parameter associated with the corrugation of silicene decreases from 0.44A to 0.36A,whereas the InSe structure remains *** energy scans reveal a significant increase in the sliding energy barrier for the case of intercalated heterostructure as compared with the unintercalated *** sliding of the silicene encounters the maximum energy barrier of 0.14 *** analysis shows the noteworthy differences between calculated in-plane and out-of-plane part of dielectric function.A variation of the planar average charge density difference,dipole charge transfer and dipole moment have been discussed to elucidate the usability spectrum of the *** employed approach based on intercalation and layer sliding can be effectively utilized for obtaining next-generation multifunctional devices.

关键词： vdw heterostructure intercalation tuning of properties layer sliding interfacial electronic properties

Impacts of weaning weights and mycotoxin challenges on jejunal mucosa-associated microbiota,intestinal and systemic health,and growth performance of nursery pigs

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Journal of Animal Science and Biotechnology 2022年第5期13卷 1440-1457页

作者： D.m.Holanda S.w.Kim Department of Animal Science North Carolina State UniversityRaleigh 27695USA

Background:This study aimed at investigating the effects of mycotoxin challenge on the growth and physiology of nursery pigs with different weaning ***:At weaning,10 pigs were euthanized to collect jejunal mucosa and 90 pigs were assigned following a randomized complete block design in a 2×2 factorial arrangement of treatments with 3 pigs per *** were:weaning weight(light:body weight,Bww>9.0 kg);and dietary mycotoxins(supplementation of 0.2 mg/kg aflatoxins,2.0 mg/kg deoxynivalenol).All diets had titanium dioxide as an external marker at 0.5%.Growth performance and fecal score were recorded until pigs achieved 20 kg Bw(light pigs average Bw=21.1 kg and heavy pigs average Bw=20.5 kg).Pigs were sampled for blood,ileal digesta,jejunal tissue and mucosa at 20 kg *** were analyzed using the mixed procedure of *** weaning,light pigs had decreased(Pmor necrosis factor-α,and increased(Pmucosa-associated *** 20 kg of Bw,light pigs had decreased(Pmycotoxins decreased(Pw,ADG,ADFI,and G/*** pigs tended to have increased fecal score on d 0(P=0.080),d 10(P=0.069),and increased(Pmalondialdehydes and interleukin *** tended to increase(P=0.060)intestinal tumor necrosis factor-α.Conclusions:Nursery pigs with light weaning weight were more susceptible to jejunal inflammation and had impaired intestinal health due to weaning stress,whereas mycotoxins diminished the health and growth of nursery pigs regardless of weaning weight.

关键词： Growth Health mycotoxins Nursery pig weaning weight

LES of film cooling for different jet fluids

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航空动力学报 2007年第4期22卷 521-530页

作者： P. Renze w. Schroeder m. meinke Aerodynamisches Institut RWTH Aachen 52062 Aachen Germany

The present paper investigates the impact of the velocity and density ratio on the turbulent mixing process in gas turbine blade film cooling.A cooling fluid is injected from an inclined pipe at α=30° into a turbulent boundary layer profile at a freestream Reynolds number of Re∞=*** jet-in-a-crossflow(JICF) problem is investigated using large-eddy simulations(LES).The governing equations comprise the Navier-Stokes equations plus additional transport equations for several species to simulate a non-reacting gas mixture.A variation of the density ratio is simulated by the heat-mass transfer analogy,i.e.,gases of different density are effused into an an air crossflow at a constant *** efficient large-eddy simulation method for low subsonic flows based on an implicit dual time-stepping scheme combined with low mach number preconditioning is *** numerical results and experimental velocity data measured using two-component particle-image velocimetry (PIV) are in excellent *** results show the dynamics of the flow field in the vicinity of the jet hole,i.e.,the recirculation region and the inclination of the shear layers,to be mainly determined by the velocity ***,evaluating the cooling efficiency downstream of the jet hole the mass flux ratio proves to be the dominant similarity parameter,i.e.,the density ratio between the fluids and the velocity ratio have to be considered

关键词：航空推进系统仿真横向流动式喷气密度比速率冷却效率薄雾冷却

Non-monotonic temperature evolution of nonlocal structure–dynamics correlation in CuZr glass-forming liquids

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Chinese Physics B 2021年第7期30卷 370-375页

作者： w J Jiang m Z Li Department of Physics and Beijing Key Laboratory of Opto-electronic Functional materials&micro-nano Devices Renmin University of ChinaBeijing 100872China

The structure–dynamics correlations in a nonlocal manner were investigated in CuZr metallic glass-forming liquids via classical molecular dynamics simulations.A spatial coarse-graining approach was employed to incorporate the nonlocal structural information of given structural order parameters in the structure–dynamics *** is found that the correlation between structure order parameters and dynamics increases with increasing coarse-graining length and has a characteristic length ***,the characteristic correlation length exhibits a non-monotonic temperature evolution as temperature approaches glass transition temperature,which is not sensitive to the considered structure order *** results unveil a striking change in the structure–dynamics correlation,which involves no fitting theoretical *** findings provide new insight into the structure–dynamics correlation in glass transition.

关键词： metallic glass-forming liquid structure–dynamics correlation molecular dynamics simulation