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Acta Mechanica Solida Sinica 2022年第2期35卷 344-356页

作者： M.K.Ramezani S.Ramesh j.Purbolaksono R.Das Centre of Advanced Manufacturing and Materials Processing Department of Mechanical EngineeringFaculty of EngineeringUniversity of MalayaKuala Lumpur 50603Malaysia Department of Mechanical Engineering University of PertaminaJakarta 12220Indonesia Sir Lawrence Wackett Aerospace Research Centre School of EngineeringRMIT UniversityMelbourneVI 3000Australia

In this work,the stress intensity factors(SIFs)for a wide range of semi-elliptical surface cracks with different inclination angles in a cylindrical bar subjected to pure tension were investigated *** main parameters considered to evaluate the SIFs were the crack size ratio(a/d),the crack aspect ratio(a/c),and the crack inclination angle(0).The dual-boundary element met hod implemented in software BEASY was used to compute the SIF values for *** her more,the general closed-form solutions were proposed to evaluate the corresponding SIFs for Mode I,Mode II and Mode III types of fracture through curve fitting *** solutions can provide accurate and reliable values of stress intensity factors for a crack on a cylindrical bar under pure tension in a rapid way compared to those obtained using computational *** addition,these results can be used as inputs for failure studies and life evaluations of cracked cylinder under working conditions.

关键词： Stress intensity factor Surface crack Solid cylinder Closed-form solution Dual-boundary element method

Control of the carrier-envelope phases of a synchronously pumped femtosecond optical parametric oscillator and its applications

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Chinese Science Bulletin 2008年第5期53卷 642-651页

作者： SUN jingHua Barry j S Gale Derryck T Reid Ultrafast Optics Group School of Engineering and Physical Sciences Heriot-Watt University Edinburgh EH14 4AS UK Laboratory of Optical Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China

The intrinsic synchronization, multi-color outputs and related carrier-envelope phases (CEP) among pulses bring advantages to synchronously pumped femtosecond optical parametric oscillators and the pumping sources for broadband frequency comb generation and ultrashort waveform coherent syn-thesis. In this paper, we discuss our latest research results in this field, which cover the following as-pects: the phase relationship and energy conservation law in an OPO and related experimental verifi-cation; control of the pumping Ti:sapphire femtosecond laser's CEP by self-referencing technology, and its repetition-rate locking by piezoelectric transducer (PZT); CEP locking of the pulses from the OPO by beating the non-phase-matched visible outputs against pump supercontinuum to obtain a driving signal for a fast PZT on the OPO end mirror; the generation of a broadband frequency comb spanning from 400 nm to 2.4 μm with 1.2 kHz bandwidth; and the realization of coherent interference between phase controlled pump pulses and signal second harmonic pulses.

关键词：光学参数振荡器载波包络相同步控制超短光脉冲

Nonmonotone adaptive trust region method based on simple conic model for unconstrained optimization

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Frontiers of Mathematics in China 2014年第5期9卷 1211-1238页

作者： Lijuan ZHAO Wenyu SUN Raimundo j. B. de SAMPAIO School of Mathematical Sciences Jiangsu Key Laboratory for NSLSCS Nanjing Normal University Nanjing 210023 China Department of Social Science Teaching Nanjing Institute of Railway Technology Nanjing 210031 China PPGEPS Pontifical Catholic University of Parana (PUCPR) Curitiba Parana Brazil

We propose a nonmonotone adaptive trust region method based on simple conic model for unconstrained optimization. Unlike traditional trust region methods, the subproblem in our method is a simple conic model, where the Hessian of the objective function is approximated by a scalar matrix. The trust region radius is adjusted with a new self-adaptive adjustment strategy which makes use of the information of the previous iteration and current iteration. The new method needs less memory and computational efforts. The global convergence and Q-superlinear convergence of the algorithm are established under the mild conditions. Numerical results on a series of standard test problems are reported to show that the new method is effective and attractive for large scale unconstrained optimization problems.

关键词： Nonmonotone technique conic model trust region method largescale optimization global convergence

Simulation of the effect of quantum dot location on a quantum dot p-i-n junction solar cell

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International journal of Modeling, Simulation, and Scientific Computing 2017年第4期8卷 140-150页

作者： C.j.Kant K.B.K.Mayya Department of Solar Energy School of Technology Pandit Deendayal Petroleum UniversityRaisan Gandhinagar382007 GujaratIndia

The investigation of the new generation of a photovoltaic cell for the optimized parameters is mainly carried out using modeling and simulation,because the fabrication of quantum structures is still a ***,new models to simulate realistic devices are *** the past,the Drift Diffusion equation has been exploited to simulate quantum well solar cells by introducing various assumptions and new *** Equilibrium Green Function’s Formalism has been widely used to study the transport in the nanostructures of the photovoltaic *** have developed a model of simulating quantum dot(QD)p-i-n junction solar cell by hybridizing the Drift Diffusion Equation and the Transfer Hamiltonian *** developed model is applied to a QD p-i-n junction solar cell to determine the optimized position of the QD within the intrinsic *** results show that when the QD is placed closer to the edges of the i-region,the highest possible efficiency is observed.

关键词： Photovoltaic quantum dot efficiency

EIS STUDY ON ZINC RICH PAINTS IN 3.5% NaCl SOLUTION BY DOUBLE-CELL TEST

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Acta Metallurgica Sinica(English Letters) 2002年第3期15卷 299-306页

作者： DM. Xie, j.M. Hu, j.M. Wang and j.Q. ZhangDepartment of Chemistry, Zhejiang University, Hangzhou 310027, ChinaState Key Laboratory for Corrosion and Protection of Metals, Institute of Metal Research, The Chinese Academy of Sciences, Shenyang 110016, China Dept. of Chem. Zhejiang Univ. Hangzhou 310027 China

This paper discussed the possibility of obtaining electrochemical impedance spectroscopy (EIS) responses of zinc rich paints (ZRP) using serial double-cell (SDC). The influence of counter electrode was outlined. An equivalent circuit (ES) for the double-cell was then discussed. The relationship between EC, the time constant, the parameters in EC of SDC and those of two single sells was discussed. The results gained by serial double cell test are consistent with those of single cell test. It can be concluded that double cell test method can be used to study ZRP completely.

关键词： Electrodes Equivalent circuits Sodium chloride Spectroscopy Zinc

Trait plasticity, not values, best corresponds with woodland plant success in novel and manipulated habitats

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journal of Plant Ecology 2013年第3期6卷 201-210页

作者： Robert j.Warren II jeffrey K.Lake Department of Biology SUNY Buffalo State1300 Elmwood AvenueBuffaloNY 14222USA Department of Biology Adrian CollegeAdrianMI49221USA

Aims The clustering of plants with similar leaf traits along environmental gradients may arise from adaptation as well as acclimation to het-erogeneous habitat *** the forces that shape plant leaf traits requires both linking variation in trait morphology with abiotic gradients and linking that trait variation with plant per-formance under varying abiotic *** the spectrum of plant types,shade-tolerant evergreen herbs are relatively low in trait plasticity,compared to deciduous and sun-adapted *** plants employ stress-tolerant strategies for survival,which coincide with relatively static trait morphologies,slow growth and hence a lower ability to adjust to changing environmental *** We investigate how the survival of two ecologically similar under-story evergreen species,Asarum arifolium and Hepatica nobilis,cor-responds with variation in six commonly measured functional traits(leaf area,specific leaf area,plant height,leaf number,leaf length and shoot mass)along natural and experimental abiotic *** examine temporal(the period 2007-9)and spatial(100 km)variations in these traits after(i)translocating 576 plants across a span from the southerm Appalachian Mountains in NC,USA,to the Piedmont,GA,USA,which includes north-and south-facing slope habitats and(ii)the experimental manipulation of diffuse light and soil *** findings We find that when translocated into a novel habitats,with novel environmental conditions that often are more extreme than the source habitat,both species appear capable of considerable mor-phological acclimation and generally converge to similar trait *** nobilis does not exhibit mean trait values particu-larly different from those of ***,but it demonstrates much greater phenotypic *** results indicate that relatively conservative plant species nonetheless acclimate and survive across heterogeneous environmental conditions.

关键词： Functional traits Asarum arifolium Hepatica nobilis niche specific leaf area understory

Using an ILU/Deflation Preconditioner for Simulation of a PEMFuel Cell Cathode Catalyst Layer

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Communications in Computational Physics 2013年第8期14卷 537-573页

作者： Kyle j.Lange Pang-Chieh Sui Ned Djilali Institute of Integrated Energy Systems University of VictoriaBCCanada Department of Mechanical Engineering University of VictoriaBCCanada Currently at Lawrence Livermore National Laboratory LivermoreCAUSA

Numerical aspects of a pore scale model are investigated for the simulation of catalyst layers of polymer electrolyte membrane fuel *** heat,mass and charged species transport together with reaction kinetics are taken into account using parallelized finite volume simulations for a range of nanostructured,computationally reconstructed catalyst layer *** effectiveness of implementing deflation as a second stage preconditioner generally improves convergence and results in better convergence behavior than more sophisticated first stage *** behavior is attributed to the fact that the two stage preconditioner updates the preconditioning matrix at every GMRES restart,reducing the stalling effects that are commonly observed in restarted GMRES when a single stage preconditioner is *** addition,the effectiveness of the deflation preconditioner is independent of the number of processors,whereas the localized block ILU preconditioner deteriorates in quality as the number of processors is *** total number of GMRES search directions required for convergence varies considerably depending on the preconditioner,but also depends on the catalyst layer microstructure,with low porosity microstructures requiring a smaller number of *** improved model and numerical solution strategy should allow simulations for larger computational domains and improve the reliability of the predicted transport *** preconditioning strategies presented in the paper are scalable and should prove effective for massively parallel simulations of other problems involving nonlinear equations.

关键词： Deflation PEM fuel cell catalyst layer pore scale model porous media preconditioner

Achieving single-lobed far-field patterns of broad area laser diode with external cavity feedback

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Chinese Optics Letters 2003年第6期1卷 334-336页

作者：葛剑虹陈军 Andreas Hermerschmidt H.j.Eichler The State Key Laboratory of Modern Optical Instrumentation Zhejiang University Hangzhou 310027 Optisches Institut Technische Univeisitat Berlin StraBe des 17. Juni 135 10623 Berlin Germany

We demonstrate a technique for single transverse mode operation of high-power broad area laser diode (BAL). In the experiment, the HR mirror is used as an external cavity mirror and the grating is used as a wavelength selective component. By tiling the HR mirror and the grating, the number of transverse modes oscillating in the cavity can be limited and the spectral bandwidth of the laser diode can be reduced. A single-lobed near diffraction-limited laser beam with the beam divergence (FWHM) of 0.43°, the spectral line-width of 0.7 nm and the output power of 350 mW are obtained. With the feedback, the power density of the output laser beam is increased 6 times in comparison with the free running.

关键词： Cavity resonators Diffraction gratings High power lasers Mirrors

Three-year follow-up in advanced pediatric keratoconus:thin corneas may not have pachymetry properly assessed after crosslinking

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International journal of Ophthalmology(English edition) 2020年第10期13卷 1561-1566页

作者： Rosalia Antunes-Foschini Sidney júlio Faria-e-Sousa Hospital das Clínicas Medical School of Ribeirao PretoUniversity of Sao PauloRibeirao Preto 14049-900Brazil Department of Ophthalmology OtorhinolaryngologyHead and Neck SurgeryMedical School of Ribeirao PretoUniversity of Sao PauloRibeirao Preto 14049-900Brazil

AIM:To analyze the crosslinking(CXL)effects in pediatric keratoconus,and to identify the patients’corneal characteristics whose pachymetry could not be adequately evaluated by Scheimpflug method after ***:Consecutive pediatric patients with progressive keratoconus underwent CXL were ***-corrected visual acuity(BCVA)and spheric equivalent(SE)were measured before and after *** CXL,groups 1 and 2 were divided based on the posterior surface Pentacam quality specifications(QS):"OK"(Group 1)and"not OK"(Group 2).The mean(RmF and RmB)and minimum(RminF and RminB)radius of curvatures of the anterior and posterior corneal surfaces,and the thinnest pachymetry(Pmin)were measured preoperatively at 3,6,12,24,and 36 *** was ***:Twenty-six patients(14 men,mean age 14±1.8 y)and median Kmax of 59.9 D initially and 61.4 D preoperatively were *** was not different before and 24 mo after *** 2 statistically differed to group 1 in that SE was more myopic before and with no difference 24 mo after CXL;RmF and RmB were steeper and Pmin was thinner *** 2,in which pachymetric changes could not be adequately evaluated after surgery,presented with significant RmF flattening,a shift to hyperopia,and more haze after ***:Patients whose pachymetry could not be adequately evaluated after CXL had steeper and thinner corneas before *** predictive factors for impaired QS after CXL are RmF,RmB,and *** advanced keratoconus,alternative methods to analyze pachymetry and the posterior surface should be considered.

关键词： keratoconus cross-linking corneal pachymetry corneal topography corneal opacity

A New Glucoside from Ceratostigma willmottianum

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Chinese Chemical Letters 1997年第10期8卷 873-874页

作者： Yue, jM Zhao, Y Xu, j Lin, ZW Sun, HD ACAD SINICA KUNMING INST BOTLAB PHYTOCHEMKUNMING 650204PEOPLES R CHINA

Ceratoside A (1), a new compound was isolated from the butanol-soluble fraction of Ceratostigma willmottianum, Its structure was determined by the utilization of 2D-NMR techniques.

关键词： A New Glucoside from Ceratostigma willmottianum CI