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Study on superprism effect in the multilayer optical thin film stack

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光学精密工程 2005年第4期13卷 454-458页

作者： SUN Xue-zheng GU Pei-fu CHEN hai-xing JIN Bo li hai-feng liU Xu State Key Laboratory of Modern Optical Instrumentations Zhejiang University Hangzhou 310027 China

Researches show that multilayer optical thin film stack can exhibit superprism effect due to their large abnormal dispersions. We investigated and simulated this effect numerically in a 1-D non-periodic film structure-Fabry-Perot filters (FPF), which possess drastic change in phase and large group delay around wavelength of peak transmittance, and fabricated this device to realize remarkable superprism effect. We tested experimentally with the maximum spatial separation shift up to 65 μm, and the experimental result is in good agreement with the theory. Compared with the traditional prism, the total thickness of our structure is only 3.3 μm, and our prism shows a stronger angular resolution of 1.8°/nm.

关键词：薄膜涂覆技术多层膜 FPF

Theoretical Studies on the Structures and Reactions of Halocarbenoids(Ⅰ)Structures and Stability of Chlorocarbenoid CHCl_2

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Chemical Research in Chinese Universities 1997年第3期13卷 256-261页

作者： li li Ji-hai, feng Sheng-yu,liu Wei (Chemical College,Shandong University,Jinan, 250100) SHANDONG UNIV CHEM COLLJINAN 250100PEOPLES R CHINA

The chlorocarbenoid , CHCl2li , was studied by means of ab initio molecular or- bital theory. Three equilibrium structures and two isomerization transition states were located. The calculations showed that the three-membered ring structure is the most stable. The 'classical tetrahedral' structure is not the local minimum on the potential energy surface.

关键词： Chlorocarbenoid isomeric structure Ab initio molecular orbital calcu- lation

Thermal Expansion Behavior of Amorphous Fe-Si-B Alloys

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Journal of Iron and Steel Research International 2011年第6期18卷 74-78页

作者： SU Chao NIU Yu chao li hai feng HUANG Guo wei WANG Xian-zhong School of Materials Science and Engineering Shandong Jianzhu University Jinan 250101 Shandong China

To study the thermal expansion of amorphous Fe-Si-B alloys, the amorphous Fe1.8Si9B1.3 and Fe73.5Nb3-CU1Si13.5B3 and their crystallized alloys were detected using thermal dilatometer. The results indicate that at the same temperature, the relative length change （ΔL/L0） values of the two Fe-based amorphous alloys decrease with increasing heating rate, but those of their crystallized alloys show an opposite trend. It is concluded that the effect of heating rate on the ΔL/L0 of amorphous and crystallized alloys is related to free volume and defects, respectively.

关键词： amorphous alloy thermal expansion heating rate free volume defect

EXPERIMENTAL AND NUMERICAL INVESTIGATION OF FREE SURFACE VORTEX

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Journal of Hydrodynamics 2008年第4期20卷 485-491页

作者： li hai-feng CHEN Hong-xun MA Zheng ZHOU Yi Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China China Ship Scientific Research Center Wuxi 214082 China

An experimental model was set up to investigate the formation and evolution of the free surface vortex. A Particle Image Velocimetry （PIV） was used to measure the free surface vortex flow field at different development stages. Flow visualization was used to locate the vortex position and find its structure. Empirical formulas about the critical submergence and the whole field structure were obtained. It is found that the tangential velocity distribution is similar to that of the Rankine vortex and the radial velocity changes little in the vortex functional scope. Vortex starts from the free surface and gradually intensifies to air entrainment vortex. The vortex core moves during the formation and evolution of the free surface vortex. Based on the experimental model, the vortex position and structure were predicted by numerical simulation combined with a vortex model and compared with that of the experiments, which shows satisfactory agreement.

关键词： free surface vortex Particle Image Velocimetry (PIV) numerical simulation rankine vortex

FORMATION AND INFLUENCING FACTORS OF FREE SURFACE VORTEX IN A BARREL WITH A CENTRAL ORIFICE AT BOTTOM

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Journal of Hydrodynamics 2009年第2期21卷 238-244页

Based on the Navier-Stokes equations with considering the effect of the Coriolis force, the finite volume method was employed to discretize the governing equations, the SIMPLE method was adopted to solve the discretized equations, and the flow field in a barrel with an outlet at the center of the bottom was simulated. The numerical results agree well with the experimental data. From the Lagrangian, the relations among the acceleration, the Coriolis force and the viscosity force were analyzed. The results show that the Coriolis force is the major factor that causes the formation of the vortex. The flow fields in the flume under different incoming flow conditions were numerically simulated using the software Fluent. The numerical simulations show good agreement with the experiments for the shape and position of the vortex.

关键词： free surface vortex Coriolis force numerical simulation

Mathematical Simulation of Burden Distribution in COREX Melter Gasifier by Discrete Element Method

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Journal of Iron and Steel Research International 2012年第9期19卷 36-42页

作者： li hai-feng , LUO Zhi-guo , ZOU Zong-shu , SUN Jun-jie , HAN li-hao , DI Zhan-xia ( Northeastern University , Shenyang 110004 , liaoning , China ) [a] Northeastern University Shenyang 110004 Liaoning China

COREX process is one of the earliest industrialized smelting reduction ironmaking technology.A numerical simulation model based on discrete element method ( DEM ) has been developed to analyze the burden distribution in the melter gasifier of COREX *** DEM considering the collisions between particles can directly reproduce the charging *** burden trajectory , the location and the burden surface profile are analyzed in melter gasifier with a mixing charging of coal and direct reduction iron ( DRI ) at the same *** the porosity of packed bed has an important effect on the gas flow distribution of melter gasifier , a method to calculate porosity has been *** distribution of DRI and coal and the porosity in the radial direction are given under different charging patterns , which is necessary to judge the gas flow distribution and provide base data for further researching the melter gasifier for the next work in the *** research results can be used to guide the operation of adjusting charging and provide important basis for optimizing the charging patterns in order to obtain the reasonable gas distribution.

关键词： COREX melter gasifier burden distribution gas distribution discrete element method

Synthesis and Spectrum Properties Studies of Tropolone Azo

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复旦学报（自然科学版） 2007年第5期46卷 774-775页

作者： li hai-feng, hai Ji-li, WANG Zi-wei, DONG Jin-long, REN Jian-guo(School of Chemistry & Chemical Engineering,ShanXi University,Taiyuan 030006,China) School of Chemistry & Chemical Engineering ShanXi University Taiyuan 030006

1 Results Tropolone,2-hydroxy-2,4,6-cycloheptatrienone,an isomer of benzoic acid,a seven-membered,non-benzenoid aromatic molecule possessing three double bonds conjugated with a carbonyl *** studies of tropolone forms complexes[1] with many metals became more important because of their potential application in the field of material science,agriculture and *** the course of our studies on the chemistry of 5-substituted tropolone derivatives[2],the synthesis of new tropolone azo derivatives ...

关键词： synthesis tropolone azo 13C NMR

Existence, Uniqueness and Blow-up of Generalized Solutions to General Nonlinear Filtration Equations

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Chinese Quarterly Journal of Mathematics 2008年第2期23卷 301-308页

作者： HUO Zhen-hong li hai-feng Department of Mathematics Zhongyuan Institute of Technology Zhengzhou 450007 China

In this paper, we consider nonnegative solutions to Cauchy problem for the general nonlinear filtration equations ut -Dj （α^ij （x, t, u）Diψ（u））＋b^i （t, u）Diu＋C（x, t, u） = 0, and obtain the existence, un... 详细信息

关键词： nonlinear filtration equation Cauchy problem generalized solution existence uniqueness blow-up

Elemental sulfur effects on Pb and Zn uptake by Indian mustard and winter wheat

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Journal of Environmental Sciences 2003年第6期15卷 836-840页

作者： CUI Yan-shan, WANG Qing-ren , DONG Yi-ting, li hai-feng (Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

A pot experiment was conducted to investigate the influence of elemental sulfur to contaminated soil on plant uptake by a heavy metal hyperaccumulator, Indian mustard(Brassica juncea) and a field crop, winter wheat(***). Elemental sulfur(S) with different rates was carried out, they were 0(S 0), 20(S 20), 40(S 40), 80(S 80), and 160(S 160) mmol/kg respectively. Extra pots with the same rates of S but without plants were used for soil sampling to monitor pH and CaCl 2-extractable heavy metal changes. The results showed that S enhanced phytoextraction of Pb and Zn from contaminated soil. Application S effectively decreased soil pH down to 1.1 as the most at the rate of S 160. The concentrations of CaCl 2-extractable Pb and Zn in soil and uptake of Pb and Zn by the plants were increased with soil pH decreased. A good correlation between CaCl 2-extractable Pb/Zn and soil pH was found(R 2 Pb = 0.847 and R 2 Zn = 0.991, n=25). With S application, soil CaCl 2-extractable Pb and Zn concentrations, concentration of Pb and Zn in plants and the amount of removal by plant uptake were significantly higher than those without S. Under the treatment of S 160, the highest CaCl 2-extractable Pb and Zn were observed, they were 4.23 mg/kg and 0.40 mg/kg, 2.7 and 2.0 times as that of the control(S 0) respectively. At the highest rates of S(S 160), both Indian mustard and winter wheat reached the highest uptake of Pb and Zn. The highest Pb concentrations in wheat and Indian mustard were 32.8 mg/kg and 537.0 mg/kg, all 1.8 times as that of the control, and the highest Zn concentrations in wheat and Indian mustard were 215.5 mg/kg and 404.0 mg/kg, 2.4 and 2.0 times as that of the control respectively. The highest removals of Pb and Zn from the contaminated soil were 0.41 mg/pot and 0.31 mg/pot by Indian mustard in the treatment of S 160 through 50 days growth.

关键词： elemental sulfur Pb Zn uptake contaminated soil