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Transmission Properties of One-Dimensional Photonic Crystals Containing Anisotropic Metamaterials

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Chinese Physics Letters 2010年第6期27卷 93-96页

作者： zhang li-wei YAN ling-ling ZHAO Yu-Huan liU li School of Physics and Chemistry Henan Polytechnic University Jiaozuo 454000 Pohl Institute of Solid State Physics Tongji University Shanghai 200092

The transmission properties of one-dimensional photonie crystals （1DPCs） containing anisotropic metamaterials are theoretically studied. It is shown that the 1DPCs can possess a similar zero average index （zero-n） gaps, the edges of zero-~ gap are weakly dependent on the incident angles, scale length and the polarization of the electromagnetic wave. When an impurity is introduced, a defect mode appears inside the zeron gap with a very weak dependence on incident angles and sealing. It is found that in such photonic crystals, a transmitted Gaussian pulse with its carrier frequency lying in the lower gap edge, in the defect mode and in the bandgap, can experience a positive or negative group delay and hence a subluminal, *** or superluminal propagation with small distortions. These properties of the photonic crystals have potential applications in the transfer of information.

关键词： CRYSTAL optics ANISOTROPY METAMATERIALS POLARIZATION of electromagnetic waves SCAliNG laws (Statistical physics) POINT defects GAUSSIAN processes ENERGY gaps (Physics)

Experimental Study of Tunneling modes in Photonic Crystal Heterostructure Consisting of Single-Negative Materials

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Chinese Physics Letters 2012年第6期29卷 159-162页

作者： zhang li-wei zhang Ye-Wen HE li WANG You-Zhen School of Physics and Chemistry Henan Polytechnic UniversityJiaozuo 454000 Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology Pohl Institute of Solid State PhysicsTongji UniversityShanghai 200092

The pair structure and the photonic crystal heterostructure consisting of ε-negative and μ-negative materials are successfully fabricated by using the transmission line *** experimentally investigate the tunneling mode properties by simulating and measuring the scattering parameters and phase *** is shown that the pair structure and the photonic crystal heterostructures possess tunneling modes when the general zero average permittivity and zero average permeability condition are *** the tunneling frequency,the field (voltage)mainly concentrates in the center of the constructed structures based on the amplification of the evanescent ***,the tunneling mode of the photonic crystal heterostructure has zero phase *** characteristics have potential applications in design of zero phase delay filters.

关键词： scattering heterostructure tunneling

Effects of seed aerosols on the growth of secondary organic aerosols from the photooxidation of toluene

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Journal of Environmental Sciences 2007年第6期19卷 704-708页

作者： HAO li-qing WANG Zhen-ya HUANG Ming-qiang FANG li zhang wei-jun Laboratory of Environmental Spectroscopy Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences Hefei 230031 China

Hydroxyl radical （.OH）-initiated photooxidation reaction of toluene was carried out in a self-made smog chamber. Four individual seed aerosols such as ammonium sulfate, ammonium nitrate, sodium silicate and calcium chloride, were introduced into the chamber to assess their influence on the growth of secondary organic aerosols （SOA）. It was found that the low concentration of seed aerosols might lead to high concentration of SOA particles. Seed aerosols would promote rates of SOA formation at the start of the reaction and inhibit its formation rate with prolonging the reaction time. In the case of ca. 9000 pt/cm^3 seed aerosol load, the addition of sodium silicate induced a same effect on the SOA formation as ammonium nitrate. The influence of the four individual seed aerosols on the generation of SOA decreased in the order of calcium chloride〉sodium silicate and ammonium nitrate〉ammonium sulfate.

关键词： toluene photooxidation secondary organic aerosol seed aerosol

Digital mapping in agriculture and environment

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Journal of Integrative Agriculture 2019年第2期18卷 249-250页

作者： SHI Zhou zhang wei-li TENG Hong-fen College of Environmental and Resource Sciences Zhejiang University Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences

Global demand for soil data and information for maintaining and improving agricultural productivity and environmental health is *** accurate and rapid digital maps of soil characteristics are of key importance for evaluation of soil fertility,precision management of crop inputs,estimation of carbon stocks,and modeling ecological responses as well as environmental threats.

关键词： DSM Digital mapping environment

Noise character analysis and the restraint of self-pulsation laser diodes

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Optoelectronics Letters 2008年第3期4卷 168-171页

作者： JIANG Ning PAN wei LUO Bin zhang wei-li ZHENG Di Institute of Optical Communication and Optical Devices South West Jiaotong University Chengdu 610031 China

We calculate the Langevin noise sources of self-pulsation laser diodes,analyze the effects of active region noise and saturable-absorption region noise on the power fluctuation as well as period fluctuation,and propose a novel method to restrain the noise effects. A visible SIMUliNK model is established to simulate the system,the results indicate that the effects of noise in absorption region can be ignored;that with the increase of DC injecting current,the noise effects enhance power jitter,and nevertheless,the period jitter is decreased;and that with external sinusoidal current modulating the self-pulsation laser diode,the noise-induced power jitter and period jitter can be suppressed greatly. This work is valuable for clock recovery in all-optical network.

关键词：噪音分析分析方法激光二极管预防措施

Tri-n-butylphosphane catalyzed ring opening of aziridines with secondary amines

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Chinese Chemical Letters 2012年第6期23卷 657-660页

作者： Wan Xuan zhang li Su wei Gang Hu Jie Zhou Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules Hubei University Wuhan 430062 China

Ring opening of aziridine with dialkyl amine took place readily in the presence of catalytic amounts of tri-n-butylphosphane （10 mol%） in the mixture of CH3CN/H20 （10：1）, giving corresponding vicinal diamines in mediate to high yields （58-95%） with good regioselectivitie, while aromatic secondary amine could not react under the same conditions. Tri-n-butylphosphane exhibited different catalytic selectivity to amines from Lewis acid catalysts.

关键词： Aziridines Ring-opening reaction Secondary amine Tfi-n-butylphosphane Vicinal diamine

Comparison of energy consumption and economic performance of organic and conventional soybean production——A case study from Jilin Province, China

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Journal of Integrative Agriculture 2015年第8期14卷 1561-1572页

作者： zhang li-wei Til Feike Jirko Holst Christa Hoffmann Reiner Doluschitz Institute of Farm Management (410c) University of Hohenheim Institute for Strategies and Technology Assessment Julius Kühn-Institut Federal Research Centre for Cultivated Plants

Modern agriculture heavily depends on energy consumption, especially fossil energy, but intensive energy input increases the production cost for producers and results in environmental *** agricultural production is considered a more sustainable system, but there is lack of scientific research on the energy consumption between organic and conventional systems in *** analysis and comparison of energy use between the two systems would help decision-makers to establish economic, effective and efficient agricultural ***, the objectives of the present study are to analyze energy inputs, outputs, energy efficiency, and economic benefits between organic and conventional soybean（Glycine max（L.） Merrill） production.A total of 24 organic farmers and 24 conventional farmers in Jilin Province, China, were chosen for investigation in 2010 production *** energy input was 71.55 GJ ha–1 and total energy output was 96.18 GJ ha–1 in the organic system, resulting in an energy efficiency（output/input） of *** energy input was 9.37 GJ ha–1 and total energy output was 113.4 GJ ha–1 in the conventional system, resulting in the energy efficiency of *** huge discrepancy in energy inputs and respective efficiencies lies in the several times higher nutrient inputs in the organic compared to the conventional production ***, the production costs ha–1 were 33% higher, and the net income ha–1 25% lower in the organic compared to the conventional soybean production *** is recommended to improve fertilizer management in organic production to improve its energetic and economic performance.

关键词： energy consumption fossil energy economic benefit organic agriculture soybean production Jilin Province China

Chaotic Solitons in Deoxyribonucleic Acid (DNA) Interacting with a Plane Wave

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Communications in Theoretical Physics 2001年第10期36卷 503-508页

作者： HAI Wen-Hua XIAO Yi FANG Jian-Shu zhang Xi-li HUANG wei-li Department of Physics Hunan Normal University Changsha 410081 China Department of Physics Huazhong University of Science and Technology Wuhan 430074 China Department of Physics Hunan Normal University Changsha 410081 China Department of Physics Hunan Normal University Changsha 410081 China Department of Physics Hunan Normal University Changsha 410081 China

Theoretical analysis of the DNA dynamics reveals that interaction between the single solitons and plane wave implies Smale-horseshoe chaos in the double helices. Solutions of the chaotic solitons are derived from a direct perturbation technique. It is demonstrated that to produce the bounded chaotic solitons, velocities of the solit ons nust be the same and equal to propagation velocity of the plane wave in DNA. The result shows that the DNA structure may be destroyed by the long action of an electromagnetic wave. It also supplies a useful method for controlling the velocities and unboundedness of the DNA motion in a tumour cell by using a plane wave.

关键词： chaos, soliton, deoxyribonucleic acid, plane wave, interaction

A wideband CMOS variable gain low noise amplifier

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High Technology Letters 2010年第2期16卷 194-198页

作者：李海松 li Zhiqun zhang Hao li wei Wang Zhigong Institute of RF-＆OE-ICS Southeast University Nanjing 210096 P.R.China

In this paper, a novel structure of linear-in-dB gain control is introduced. Based on this structure, a wideband variable gain low noise amplifier （VGLNA） has been designed and implemented in 0.18μm RF CMOS technology. The measured resuhs show a good linear-in-dB gain control characteristic with 15 dB dynamic range. It can operate in the frequency range of MHz and consumes 30mW from 1.8V power supply. The minimum noise figure is 4.1 dB at the 48 - 860 maximum gain and the input P1dB is greater than - 16.5dBm.

关键词： low noise amplifier (LNA) wideband linear-in-dB CMOS