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Chinese Journal of Chemical Physics 2014年第3期27卷 259-264页

作者： yu-jin zhang yu-zhi Song Chuan-kui Wang College of Physics and Electronics Shandong Normal University Jinan 250014 China

By numerically solving the Maxwell-Bloch equations using an iterative predictor-corrector finite-difference time-domain technique, we investigate propagating properties of a few-cycle laser pulse in a 4,4＇-bis（di-n-butylamino） stilbene （BDBAS） molecular medium when a static electric field exists. Dynamical two-photon absorption （TPA） cross sections are obtained and optical limiting （OL） behavior is displayed. The results show that when the static electric field intensity increases, the dynamical TPA cross section is enhanced and the OL behavior is improved. Moreover, both even- and odd-order harmonic spectral components are generated with existence of the static electric field because it breaks the inversion symmetry of the BDBAS molecule. This work provides a method to modulate the nonlinear optical properties of the BDBAS compounds.

关键词： Static electric field Optical limiting Two-photon absorption Organic molecule

General synthesis of sponge-like ultrafine nanoporous metals by dealloying in citric acid

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Nano Research 2016年第8期9卷 2467-2477页

作者： Hongjie Xu Shujie Pang yu jin Tao zhang ing 100191 China

A general method is proposed to synthesize ultrafine nanoporous Cu, Ag, and Ni with novel sponge-like morphologies, high porosities, and large surface areas. The materials are produced by dealloying Mgc~/IzsY10 （M = Cu, Ag, and Ni） metallic glasses in citric acid. Citric acid played a key role due to its capping effect, which reduced the surface diffusion of metals. A structural model consistent with the sponge-like morphology was constructed to calculate the porosity and the surface area. The mechanism of the dealloying process in citric acid, involving ligament formation and coarsening, was illustrated. The mechanism was capable of explaining the experimental trends of dealloying, especially the morphology. A glucose sensor, which can be further developed into a high-precision real-time glucose monitor for medical use, was constructed using sponge-like nanoporous copper. Our findings are not only relevant to understanding the dealloying mechanism of metallic glasses, but also provide promising materials for multiple applications.

关键词： sponge-like nanoporousmetals citric acid surface diffusion metallic glasses ultrafine structure

Structures and energetics of semicoherent interfaces of precipitates in hcp/bcc systems:A molecular dynamics study

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Journal of Materials Science & Technology 2021年第8期67卷 50-60页

作者： jin-yu zhang Fu-Zhi Dai Zhi-Peng Sun Wen-Zheng zhang Key Laboratory of Advanced Materials(MOE) School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Science and Technology of Advanced Functional Composite Laboratory Aerospace Research Institute of Materials&Processing TechnologyBeijing 100076China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610041China

α/β(hcp/bcc)interfaces are of great importance in the microstructure development and the mechanical properties of titanium and zirconium *** work contributes to the study of interface energetics and interfacial structures of the precipitate in the hcp/bcc system based on a simulation study using molecular statics(MS)and molecular dynamics(MD).The input orientation relationship(OR)was calculated based on the O-line *** on the energy of the interfaces containing the invariant line(IL),two preferred facets were determined by the Wulff construction,which explained the observed orientations of the habit plane(HP)and the side facet(SF).The deviation of the observed precipitate morphology from the equilibrium shape was discussed in terms of interface *** structures of the interfaces surrounding a three-dimensional(3 D)precipitate,including the preferred facets and the end face,were obtained at the atomic *** simulated dislocation structures and atomic structures in these interfaces are in good agreement with those of the experimental observations for Ti-Cr alloys.A method was suggested for modifying the O-cell structure with the guidance of the relaxed structure,yielding consistency between the calculated dislocation structure based on the generalized O-element approach and the simulation results.

关键词： Interface Misfit dislocation Precipitate

An Extended Method for Constructing Travelling Wave Solutions to Nonlinear Partial Differential Equations

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Communications in Theoretical Physics 2005年第3X期44卷 407-414页

作者： JIAO Xiao-yu WANG jin-Huan zhang Hong-Qing Department of Applied Mathematics Dalian University of Technology Dalian 116024 China

In this paper, an extended method is proposed for constructing new forms of exact travelling wave solutions to nonlinear partial differential equations by making a more general transformation. For illustration, we apply the method to the asymmetric Nizhnik-Novikov-Vesselov equation and the coupled Drinfel＇d-Sokolov-Wilson equation and successfully cover the previously known travelling wave solutions found by Chen＇s method .

关键词： soliton solution asymmetric Nizhnik-Novikov-Vesselov equation coupled Drinfel'd-Sokolov-Wilson equation

Lumped parameter model for resonant frequency estimation of a thermoacoustic engine with gas-liquid coupling oscillation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第3期12卷 232-237页

作者： Ke TANG Tian LEI Xiao-gang LIN Tao jin yu zhang Institute of Refrigeration and Cryogenics Zhejiang University Hangzhou 310027 China

Gas-liquid coupling oscillation is a novel approach to reducing the resonant frequency and to elevating the pressure amplitude of a thermoacoustic *** a thermoacoustic engine is used to drive low-frequency pulse tube refrigerators,the frequency matching between the thermoacoustic engine and the refrigerator plays an important *** on an acoustic-electric analogy,a lumped parameter model is proposed to estimate the resonant frequency of a standing-wave thermoacoustic engine with gas-liquid coupling ***,a simplified lumped parameter model is also developed to reduce the computation *** resonant frequency dependence on the mean pressure,the gas space volume,and the water column length is computed and *** impact of different working gases on the resonant frequency is also *** effectiveness of the models is validated by comparing the computed results with the experimental data of the gas-liquid coupling oscillation *** increase in the mean working pressure can lead to a rise in the resonant frequency,and a lower resonant frequency can be achieved by elongating the liquid *** comparison with nitrogen and argon,carbon dioxide can realize a lower frequency due to a smaller specific heat ratio.

关键词： Thermoacoustic engine Gas-liquid coupling oscillation Acoustic-electric analogy Resonant frequency

A molecular dynamics study on formation of the self-accommodation microstructure during phase transformation

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Journal of Materials Science & Technology 2019年第11期35卷 2638-2646页

作者： Zhi-peng Sun jin-yu zhang Fu-zhi Dai Ben Xu Wen-zheng zhang Key Laboratory of Advanced Materials(MOE) School of Materials Science and EngineeringTsinghua UniversityBeijing100084China Science and Technology of Advanced Functional Composite Laboratory Aerospace Research Institute of Materials and Processing TechnologyBeijing100076China

Self-accommodation microstructure,a typical crystallographic texture developed from phase transformation,is often observed in various *** this work,a molecular dynamics simulation was conducted to reveal the fine details of self-accommodation microstructure evolution during the phase transformation from austenite to ferrite in pure *** growth and shrinkage of ferrite grains with different orientation relationships(ORs)are interpreted based on the analysis combining the elastic interaction energy and the interfacial *** was found that the strain energy determines the priority of potential ORs,while the interfacial energy selects the specific preferred ORs to *** present atomistic process and energetic interpretation of the self-accommodation microstructure provide helpful insight into phase transformation textures observed in various alloys.

关键词： Self-accommodation microstructure Molecular dynamics Orientation relationship Elastic interaction energy Interfacial energy

An Easy Way to Quantify the Adhesion Energy of Nanostructured Cu/X(X=Cr,Ta,Mo,Nb,Zr) Multilayer Films Adherent to Polyimide Substrates

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Acta Metallurgica Sinica(English Letters) 2016年第2期29卷 181-187页

作者： Kai Wu jin-yu zhang Gang Liu Jiao Li Guo-Jun zhang Jun Sun State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong University School of Materials Science and Engineering Xi’an University of Technology

An approach based on film buckling under simple uniaxial tensile testing was utilized in this paper to quan- titatively estimate the interfacial energy of the nanostructured multilayer films （NMFs） adherent to flexible substrates. The interfacial energies of polyimide-supported NMFs are determined to be ~ 5.0 J/m2 for Cu/Cr, ~4.1 J/m2 for Cu/Ta, ~ 2.8 J/m2 for Cu/Mo, ~ 1.1 J/m2 for Cu/Nb, and ~ 1.2 J/m2 for Cu/Zr NMFs. Furthermore, a linear relationship between the adhesion energy and the interfacial shear strength is clearly demonstrated for the Cu-based NMFs, which is highly indicative of the applicability and reliability of the modified models.

关键词： Uniaxial tensile testing Nanostructured multilayer films Flexible substrates Bucklingbehaviors Adhesion energy

Theoretical Analysis on Optical Limiting Properties of Newly Synthesized Graphene Oxide-Porphyrin Composites

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Chinese Journal of Chemical Physics 2015年第3期28卷 257-262,I0001页

作者： yu-jin zhang Wen-jing Yang Jian-zhong Fan yu-zhi Song Chuan-kui Wang College of Physics and Electronics Shandong Normal University Jinan 250014 China

Optical limiting （OL） properties and two-photon absorption （TPA） of a series of covalently linked graphene oxide-porphyrin composite materials have been investigated by numerically solving the rate equations and field intensity equation with an iterative predictor-corrector finite-difference time-domain technique in nanosecond time domain. Our results show that graphene oxide-porphyrin composites exhibit enhanced OL behavior and possess larger TPA cross section compared with individual porphyrins. Interestingly~ unlike the previous result that porphyrin with heavier central metal shows better nonlinear abilities than that with- out metal substitute, graphene oxide-metal free porphyrin composite has stronger nonlinear absorption properties compared with graphene oxide-metal porphyrin composite. The com- putational results are in reasonable agreement with the experimental ones. Special attention has been paid to the influence of thickness of the medium and pulse width on TPA cross sections, which presents that larger TPA cross sections are obtained as the medium is thicker or the pulse duration is wider.

关键词： Optical limiting Two-photon absorption Graphene oxide Porphyrin

Plasmonic Core-Shell Nanostructures Enhanced Spectroscopies

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Chinese Journal of Chemistry 2022年第3期40卷 392-406页

作者： Jun Zhou Di-Ye Wei yu-jin zhang Hua zhang Jian-Feng Li State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringCollege of MaterialsCollege of EnergyFujian Key Laboratory of Advanced MaterialsXiamen UniversityXiamenFujian 361005China College of Optical and Electronic Technology China Jiliong UniversityHangzhouZhejiang 310018China

Core-shell nanostructures constituted by a plasmonic core and an ultrathin shell have drawn enormous attentions in enhanced spectroscopies,catalysis,energy,and other fields because of their splendid properties such as multifunctionality,stability,and *** this article,we summarized the endeavors made by our group in the past decade about the core-shell nanostructures in the shell-isolated nanoparticle-enhanced Raman spectroscopy(SHINERS)and plasmon-enhanced ***,the potential challenges and perspectives about core-shell nanostructures in spectroscopies have also been ***,we believe this article would provide an avenue for a comprehensive understanding of enhanced spectroscopies with core-shell nanostructures.

关键词： Raman spectroscopy Nanostructures Electrochemistry Heterogeneous catalysis In-situ characterization

Microwave-assisted regeneration of hypercrosslinked polymeric adsorbent saturated with nitrophenols

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Journal of Environmental Sciences 2006年第4期18卷 765-770页

作者： HAN Yong-zhong JIANG Li-yu CHEN jin-long zhang Quan-xing National Key Laboratory of Pollution Control and Resources Reuse School of the Environment Nanjing University Nanjing 210093 China

Thermal regeneration ofhypercrosslinked polymeric adsorbent （HPA） was performed at 67℃. Experiments were carried out using a multimode microwave oven operating at 2450 MHz and a thermostatic water bath so as to compare the effect of the different heating mechanisms on the regeneration efficiency of the HPA saturated with nitrophenols. The temperature rise action of the heterogeneous regeneration system under microwave irradiation was described. Additionally, a complete structure and chemical characterization of the regenerated HPA was also carried out in order to study the influence of the subsequent regeneration cycles on the structure and the adsorption capacities of the adsorbents. Structure characterization of the regenerated HPA was accomplished by means of the analysis of FTIR spectra.

关键词： polymeric adsorbent microwave irradiation adsorption structure