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A DFT Study on the Reaction Mechanism Involved in the Synthesis of Sodium Azide via Hydrazine Hydrate Method

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Chinese Journal of Structural Chemistry 2018年第7期37卷 1045-1051页

作者：孙华云李明晶刘永军 School of Metallurgy Shandong Vocational College of Industry School of Chemistry and Chemical Engineering Shandong University

Sodium azide is a widely used inorganic compound. Besides the commonly used method of ＂Wislicenus process＂ which uses ammonia, nitrous and sodium as materials, the hydrazine hydrate route is also employed for the preparation of sodium azide particularly in laboratory. However, because many species are involved in the reaction system, the reaction details for the hydrazine hydrate route are still unclear. A comprehensive understanding of the reaction mechanism may provide meaningful help for optimizing the production process. In this work, the reaction mechanism for the synthesis of sodium azide by hydrazine hydrate route has been studied using density function theory（DFT） method. On the basis of our calculations, the reaction details, including the energetics of ten elementary steps, the structures of intermediates and transition states as well as the influence of inorganic acids and alcohols, were illuminated at the atomistic level. Both the two steps, the generation of key intermediate（NH2-NH-NO） and the trans-cistransformation of NH2-NH-NO, are suggested to be the possible rate-limiting step, corresponding to the energy barriers of 20.3 and 22.7 kcal/mol, respectively. In the early reaction steps to generate NH2-NH-NO, the main role of sulphuric acid is to donate proton, which can be replaced by nitric acid or hydrochloric acid. From the energy point of view, isopropanol has similar reactivity as methanol and ethanol.

关键词： sodium azide hydrazine hydrate DFT method isopropanol sulphuric acid

Robust H_∞ Filter Design for Time-delay Systems with Saturation

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International Journal of Automation and computing 2013年第4期10卷 368-374页

作者： Xiao-Fang Hong Yu-Zhen Wang Hai-Tao Li School of Control Science and Engineering Shandong University Department of Electrical and Automation Shandong Labor Vocational and Technical College

This paper investigates the H∞ filtering problem for a class of linear continuous-time systems with both time delay and saturation. Such systems have time delay in their state equations and saturation in their output equations, and their process and measurement noises have unknown statistical characteristics and bounded energies. Based on the Lyapunov-Krasovskii stability theorem and the linear matrix inequalities （LMIs） technique, a generalized dynamic filter architecture is proposed, and a filter design method is developed. The linear H∞ filter designed by the method can guarantee the H∞ performance. The parameters of the designed filter can be obtained by solving a kind of LMI. An illustrative example shows that the design method proposed in this paper is very effective.

关键词： H∞ filter saturation time delay nonlinear system linear matrix inequality.

Repeat-until-success measurement-based scheme for controlled phase gates in a cavity

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Chinese Optics Letters 2009年第1期7卷 82-84页

作者：李德存韩春兰冯勋立 shandong vocational and Trade college Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences

We propose a new repeat-until-success （RUS） measurement-based scheme to implement quantum controlled phase gates according to the effect of dipole-induced-transparency （DIT） in a cavity and single-photon interference at a 50：50 beam-splitter. In our scheme, the DIT effect can appropriately attach a photon to the state of the dipoles according to their initial state, and in this way, a suitably encoded dipole-photon state is thus prepared. The measurement of the photon after it passing through a 50：50 beam-splitter can project the encoded matter-photon state to either a desired phase gate operation for the matter qubits or to their initial states. The recurrence of the initial state permits us to implement the desired entangling gate in a RUS way.

关键词： Telecommunication networks

The dynamical properties of a Rydberg hydrogen atom between two parallel metal surfaces

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Chinese Physics B 2011年第3期20卷 191-197页

作者：刘伟李洪云杨善迎林圣路 News Center University of Jinan Department of Information Engineering Laiwu Vocational and Technical College college of Physics and Electronics Shandong Normal University

This paper presents the dynamical properties of a Rydberg hydrogen atom between two metal surfaces using phase space analysis methods. The dynamical behaviour of the excited hydrogen atom depends sensitively on the atom-surface distance d. There exists a critical atom-surface distance dc = 1586 a.u. When the atom-surface distance d is larger than the critical distance de, the image charge potential is less important than the Coulomb potential, the system is near-integrable and the electron motion is regular. As the distance d decreases, the system will tend to be non-integrable and unstable, and the electron might be captured by the metal surfaces.

关键词： Poincare surfaces of section chaos the phase space analysis methods

Hurst's Exponent Determination for Radial Distribution Functions of In, Sn and In-40 wt%Sn Melt

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Chinese Physics Letters 2011年第12期28卷 59-62页

作者： ZHOU Yong-Zhi LI Mei GENG Hao-Ran YANG Zhong-Xi SUN Chun-Jing School of Materials Science and Engineering University of Jinan Jinan 250022 shandong Transport vocational college Weifang 261206

Hurst's exponent of radial distribution functions(RDFs)within the short-range scope of In,Sn and In-40 wt%Sn melts are determined by the rescaled range analysis ***'s exponents H are between 0.94 and 0.97,which display long−range *** short-range scope,the number of particles from a reference particle belongs to fractional Brownian *** RDF serials are randomly scrambled,Hurst's exponents all dramatically dropped,which proves long-range dependence.H irregularly varies as the temperature rises,but the change tendency is not consistent with the correlation radius rc.

关键词： method motion belongs

Ferroelectric properties of sol-gel derived Nd-doped SrBi_4Ti_4O_(15) thin films

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Journal of Rare Earths 2008年第4期26卷 575-578页

作者：范素华张丰庆王培吉任艳霞 Department of Materials Science and Engineering Shandong Jianzhu University Department of Science University of Jinan Jiyuan vocational and Technical college

Neodymium-doped strontium bismuth titanate （SrBi4-xNdxTi4O15） ferroelectric thin films were fabricated using the sol-gel method on Pt/Ti/SiO2/Si substrates. The influence of Nd content on the microstructure and ferroelectric properties of SrBi4-xNdxTi4O15 thin films were systematically studied. The results indicated that the SrBi3.88Nd0.12Ti4O15 （SBNT0.12） thin films had better ferroelectric properties, with a remanent polarization of （2Pr） of 34.3 μC/cm^2 and a coercive field （2Ec） of 220 kV/cm. This could be attributed to the fact that SBNT0.12 ferroelectric thin films consisted of more and larger ball-like grains, approximately 150-200 nm, with structure distortion, which greatly contributed to the improvement of the ferroelectric properties of the films. Furthermore, the film exhibited a good fatigue resistant property. The value of 2Pr after 10^10 switching cycles did not change significantly. The SrBi3.88Nd0.12Ti4O15 films were promising candidates for the application of FeRAMs.

关键词： SrBi4-xNdxTi4O15 thin films sol-gel method ferroelectric properties rare earths

Waveform Distortions in Femtosecond Laser Pulses Transmitting through Coated Optical Fiber Probes

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Chinese Physics Letters 2010年第6期27卷 221-224页

作者： LIU Gui-Yuan HAN Jun-Ling LIU Man TENG Shu-Yun CHENG Chuan-Fu college of Physics and Electronics Shandong Normal University Jinan 250014 School of Science Shandong 3ianzhu University Jinan 250101 Department of Electronic Engineering Jinan vocational college Jinan 250103

We calculate the light field in metal-coated optical fiber probes under illumination of femtosecond laser pulses with the three-dimensional finite-difference time-domain method. By choosing the maximum of the calculated light field data in the time period of one light wave cycle at each spatial point, we obtain the amplitude distributions instead of the conventional light field distribution of a time instant. It is found that with an incident plane wave pulse of y-polarization, the output amplitude distributions of y-polarization have roughly a circled-cross-like pattern with two arc-like zero-amplitude zones. By analyzing the y-polarized waveforms versus time at the points near the arc-like zero-amplitude zones, we find that waveform distortions appear at points in the neighborhood of the zero amplitude lines and in the time intervals when two wave-packets overlap.

关键词： ELECTRIC distortion FEMTOSECOND lasers SURFACE coatings OPTICAL fibers FINITE differences TIME-domain analysis OPTICAL polarization

Synthesis of one-dimensional GaN nanorods by Tb intermediate layer with different thicknesses

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Rare Metals 2016年第12期35卷 937-939页

作者： Jin-Hua Chen Ping Shi Yu-Lan Li Xue-Lei Sun Cheng-Shan Xue Ji-Yuan Guo Department of Mechanical and Electrical Engineering Zhenjiang Vocational Technical College college of Physics and Electronics Shandong Normal University college of Mathematics and Physics Jiangsu University of Science and Technology

GaN nanorods were synthesized by magnetron sputtering and ammonification system, and the thickness of Tb intermediate layer was changed to study the effect on GaN nanorods. The resultant was tested by scanning electron microscopy （SEM）, X-ray diffraction （XRD）, transmission electron microscopy （TEM）, high-resolution transmission electron microscopy （HRTEM）, and photo- luminescence （PL） spectra. The results show that the thickness of Tb layer has an evident effect on the modality, quality, and luminescence properties of GaN nanorods. PL spectra at room temperature show a very strong emission peak at 368 nm and a weak emission peak at 387 nm, and the intensities of the peak for the produced samples reach the maximum when Tb layer is 20 nm. Finally, the optimal thickness of 20 nm of Tb intermediate layer for synthe- sizing GaN nanostructures is achieved.

关键词： GaN nanorods Tb intermediate layer Single crystal Photoluminescence

Helical particle manipulation based on power-exponent-phase acoustic vortices generated by a sector transducer array

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Chinese Physics B 2023年第6期32卷 333-341页

作者：王青东胡彦涛王胜利李洪宇 college of Ocean Science and Engineering Shandong University of Science and TechnologyQingdao 266590China Department of Modern Architecture Linyi Vocational CollegeLinyi 276017China

The characteristics of traditional acoustic vortices(AVs) were verified by the cross-sectional axisymmetric pressure distributions with perfect phase spirals around the center pressure null. In order to generate a non-axisymmetric pressure distribution, the concept of power-exponent-phase was first introduced into the formation of AV beams, named “powerexponent-phase acoustic vortices(PAVs)” in this paper. Based on a ring-array of sector transducers, the helical distribution of the low-pressure valley in cross-sections of PAVs, which enables particles to move from a distant position to the center low-potential well along a certain spiral passageway, was proved theoretically. The particle manipulation behavior for PAVs with a power order of 2 is numerically modeled and experimentally confirmed. The results show that PAVs with a nonaxisymmetric spiral pressure distribution can be used to realize the directional transport of particles in an enlarged scope,suggesting prospective application potential in biomedical engineering.

关键词： acoustic vortices power-exponent-phase spiral potential well sector transducer array particle manipulation