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Chinese Journal of Electronics 2014年第2期23卷 361-365页

作者： YIN Hongtao fu Ping SUN zhen Automatic Test and Control Institute Harbin Institute of Technology

Discrete cosine transform(DCT) is an effective method to extract proper features for face recognition. Discrete cosine transform can only map the resource data to another data field instead of compress *** to select the DCT coefficients that are most effective for classification is an important problem. This paper proposes a novel method to search the best discriminant combination of DCT coefficients. A feature selection algorithm according to the separability criterion is used to preselect the DCT coefficients, and then follows a search algorithm based on binary particle swarm optimization and support vector machine to find an optimal combination of the DCT coefficient. The performance of the algorithm is assessed by computing the recognition rate and the number of selected features on ORL database and Cropped Yale database.

关键词： Separability criterion Binary particle swarm optimization Support vector machine Face recognition Feature selection

Design of non-polarizing thin film edge filters

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第6期7卷 1037-1040页

作者： GU Pei-fu zhenG zhen-rong State Key Laboratory of Modern Optical Instrumentation Zhejiang University Hangzhou 310027 China

The separation between s- and p-polarization components invariably affects thin film edge filters used for tilted incidence and is a difficult problem for many applications, especially for optical communication. This paper presents a novel design method to obtain edge filters with non-polarization at incidence angle of 45°. The polarization separation at 50% trans-mittance for a long-wave-pass filter and a short-wave-pass filter is 0.3 nm and 0.1 nm respectively. The design method is based on a broadband Fabry-Perot thin-film interference filter in which the higher or lower interference band at both sides of the main transmittance peak can be used for initial design of long-wave-pass filter or short-wave-pass filter and then can be refined to reduce the transmittance ripples. The spacer 2H2L2H or 2L2H2L of the filter is usually taken. Moreover, the method for expanding the bandwidth of rejection and transmission is explained. The bandwidth of 200 nm for both rejection region and transmission band is obtained at wavelength 1550 nm. In this way, the long-wave-pass and short-wave-pass edge filters with zero separation between two polarization components can easily be fabricated.

关键词： Thin film optics Interference edge filters Non-polarization design

Effect of SDBS on interfacial electron transfer at the liquid/liquid interface by thin layer method

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Chinese Chemical Letters 2009年第9期20卷 1115-1118页

作者： Xiu Hui Liu Cun Wu Dong Kai Zhang fu Peng Zhi zhen Ding xiao Quan Lu College of Chemistry & Chemical Engineering Northwest Normal University Lanzhou 730070 China

The effect of an adsorbed anionic surfactant sodium dodecyl benzene sulfonate （SDBS） on electron transfer （ET） reaction between ferricyanide aqueous solution and decamethylferrocene （DMFc） located on the adjacent organic phase was investigated for the first time by thin layer method. The adsorption of SDBS at the interface resulted in a decay in the cathodic plateau current of bimolecular reaction with increasing concentrations of SDBS in aqueous phase. However, the rate constant of electron transfer （ket） increased monotonically as the SDBS concentrations increased from 0 to 200 p, moFL. The experimental results showed that SDBS formed patches on the interface and influenced the structure of electrical double layer. 2009 xiao Quan Lu. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Anionic surfactant Liquid/liquid interface Electron transfer Thin layer method

Clustering Property of Wolf-Rayet Galaxies in the SDSS

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Chinese Journal of Astronomy and Astrophysics 2008年第2期8卷 211-218页

作者： Wei Zhang Xu Kong fu-zhen Cheng Center for Astrophysics University of Science and Technology of China Hefei 230026

We have analysed, for the first time, the clustering properties of Wolf-Rayet （W-R） galaxies, using a large sample of 846 W-R galaxies selected from the Data Release 4 （DR4） of the Sloan Digital Sky Survey （SDSS）. We compute the cross-correlation function between W- R galaxies and a reference sample of galaxies drawn from the DR4. We compare the function to the results for control samples of non-W-R star-forming galaxies that are matched closely in redshift, luminosity, concentration, 4000-A break strength and specific star formation rate （SSFR）. On scales larger than a few Mpc, W-R galaxies have almost the same clustering amplitude as the control samples, indicating that W-R galaxies and non-W-R control galaxies populate dark matter haloes of similar masses. On scales between 0.1-1 h^-1 Mpc, W-R galaxies are less clustered than the control samples, and the size of the difference depends on the SSFR. Based on both observational and theoretical considerations, we speculate that this negative bias can be interpreted by W-R galaxies residing preferentially at the centers of their dark matter haloes. We examine the distribution of W-R galaxies more closely using the SDSS galaxy group catalogue of Yang et al., and find that -82% of our W-R galaxies are the central galaxies of groups, compared to -74% for the corresponding control galaxies. We find that W-R galaxies are hosted, on average, by dark matter haloes of masses of 10^12.3M⊙, compared to 10^12.1M⊙ for centrally-located W-R galaxies and 10^12.7M⊙ for satellite ones. We would like to point out that this finding, which provides a direct observational support to our conjecture, is really very crude due to the small number of W-R galaxies and the incompleteness of the group catalogue, and needs more work in future with larger samples.

关键词： galaxies: distances and redshifts -- galaxies: starburst -- stars: Wolf-Rayet

Genome-wide analysis of the invertase genes in strawberry(Fragaria×ananassa)

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Journal of Integrative Agriculture 2021年第10期20卷 2652-2665页

作者： YUAN Hua-zhao PANG fu-hua CAI Wei-jian CHEN xiao-dong ZHAO Mi-zhen YU Hong-mei Institute of Pomology Jiangsu Academy of Agricultural Sciences/Jiangsu Key Laboratory for Horticultural Crop Genetic ImprovementNanjing 210014P.R.China

Sugar is an important material basis in fruit development,and strawberry fruit flavour and sweetness largely depend on the sugar content and ***(INVs)play an important role in the regulation of sugar accumulation because they irreversibly catalyse the hydrolysis of sucrose into the corresponding nucleoside diphosphate-glucose,glucose or fructose in *** this work,we provided a comprehensive analysis of the INV gene family in octoploid strawberry(Fragaria×ananassa),including the gene structure,chromosomal locations,conserved domains,and gene evolution and expression profiles during strawberry fruit *** study revealed that polyploid events resulted in the abundant amplification(almost three-or four-fold)of the INV gene in the F.×ananassa genome,and these amplified INV genes showed dominant expression in strawberry *** than half of the FaINVs transcripts with low expression had incomplete coding sequences by alternative *** studies have shown that cell wall invertases(CWINV)are involved in the regulation of phloem unloading and sink strength *** expression of FaCWINV1 was markedly upregulated during fruit development and strongly expressed in ripe ***,a significant correlation was observed between the total sugar content and the FaCWINV1 expression *** findings suggest that FaCWINV1 may be involved in sugar accumulation in strawberry *** together,the results of our study will be beneficial for further research into the functions of INVs in the regulation of fruit ripening.

关键词： strawberry sugar invertases fruit ripening

Experimental Quantum Key Distribution over 14.8 km in a Special Optical Fibre

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Chinese Physics Letters 2003年第5期20卷 608-610页

作者： GUIYou-zhen HANzheng-fu MOxiao-Fan GUOGuang-Can KeyLaboratoryofQuantumInformaiton UniversityofScienceandTechnologyofChinaChineseAcademyofSciencesHefei230026

We present an experimental set-up for quantum key distribution in a special optical fibre at the wavelength of 850 nm. The system employs the BB84 protocol to establish a secret key between Alice and Bob over 14.8 km. The key is encoded in the phase of very weak laser of average photon number 0.11 per pulse. The measured error rate is lower than 10%.

关键词：光学纤维量子通信编码量子传输光脉冲激光传输

Research on immunosensor based on porous silicon

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Optoelectronics Letters 2008年第5期4卷 328-330页

作者： XUE Tao LV xiao-yi JIA zhen-hong HOU Shi-bin ZHANG fu-chun School of physies Xinjiang University Urumgi 830046 China School of Electronic and Information Engineer Xi ＇an Jiaotong University Xi ＇an 710049 China School of Information Science ＆ Engineering Xinjiang University Urumqi 830046 China Key Laboratory of Biological Resources and Gene Engineering of Xinjiang College of Life Sciences and Technology Xinjiang University Urumgi 830046China.

Porous silicon is functionalized using thermal oxidation and silanization. The HYSA antibodies are immobilized to the porous surface in this paper. The changes in the reflection spectrum and photoluminescence spectrum are investigated when BSA are attached to the PS surface. The result shows that the luminescence peak of PS disappears. After the antigen-antibody reaction,the higher light emission is observed and the reflection spectrum also red shifts. Therefore,this research lays a foundation for the development of sensitive label-free optical immunosensor.

关键词：敏感器件硅硅烷化氧化 HYSA抗体

Photoactivated Circularly Polarized Room-Temperature Phosphorescence from Phenoselenazine Derivative and Its Application in Information Security

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Chinese Journal of Chemistry 2024年第20期42卷 2499-2506页

作者： Shiyao fu Yi Chen Yujun Xie zhen Li Institute of Molecular Aggregation Science Tianjin UniversityTianjin 300072China Joint Schoolof National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New City FuzhouFujian 350207China Hubei Key Lab on Organic and Polymeric Opto-Electronic Materials Department of ChemistryWuhan UniversityWuhanHubei 430072China

Room-temperature phosphorescence(RTP)materials have experienced rapid development due to their potential in organic light-emitting diode,information security,bioimaging,***,the design of chiral organic phosphors with circularly polarized RTP(CPP)property remains a formidable ***,we introduce a chiral perturbation approach using a combination of chiral binaphthol and phenoselenazine derivative to achieve *** photoactivated CPP in polystyrene(PS)film demonstrates a luminescence dissymmetry factor(glum),emission efficiency,and RTP lifetime up to 9.32×10^(–3),27.0%,and 40.0 ms,*** remarkable sensitivity of PS film to oxygen and temperature enables the adjustable emission colors,ranging from green to offwhite and blue under varying *** doping systems,utilizing hosts of triphenylphosphine and 9-phenylcarbazole,demonstrate an extended CPP lifetime of 85.9 ms and exhibit a persistent mechanoluminescence property with low pressure response threshold as low as 0.15 *** information security provided by this CPP material was attained via the using of diverse emission colors and afterglow generated by distinct UV irradiation times and host ***,it can also be achieved by observing different emission patterns using R-and *** research has presented a reliable approach for producing CPP materials with high emission efficiency and glum.

关键词： Room-temperature phosphorescence Circularly polarized luminescence Spin-orbit coupling Host-guest systems Multi-stimuli-responsive luminescence Phenoselenazine

Effects of initial grain size and strain on grain boundary engineering of high-nitrogen CrMn austenitic stainless steel

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International Journal of Minerals,Metallurgy and Materials 2018年第8期25卷 922-929页

作者： zhen-hua Wang Jian-jun Qi Wan-tang fu School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China HBIS Group Technology Research Institute Shijiazhuang 050023China

18 Mn18 Cr0.5 N steel with an initial grain size of 28–177 μm was processed by 2.5%–20% cold rolling and annealing at 1000°C for 24 h,and the grain boundary character distribution was examined via electron backscatter *** strain(2.5%) favored the formation of low-Σ *** this strain,the fraction of low-Σ boundaries was insensitive to the initial grain ***,specimens with fine initial grains showed decreasing grain size after grain boundary engineering *** fraction of low-Σ boundaries and the(Σ9 + Σ27)/Σ3 value decreased with increasing strain; furthermore,the specimens with fine initial grain size were sensitive to the ***,the effects of the initial grain size and strain on the grain boundary engineering were discussed in detail.

关键词： grain boundary engineering grain boundary character distribution grain size strain austenitic stainless steel

Morphology-controlled synthesis of Al/Fe_2O_3 nano-composites via electrospinning

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Chinese Chemical Letters 2015年第12期26卷 1535-1537页

作者： zhen Wang Tian-fu Zhang zhen Ge Yun-Jun Luo School of Materials and Engineering Beijing Institute of Technology

In this article, nano-scale Al/Fe2O3 composites with different morphologies were successfully obtained by a simple electrospinning technique, which is based on a surfactant（polyvinyl pyridine, PVP） in a mixture of N,N-dimethylformamide（DMF） and 2-propanol. The electrospun Al/Fe2O3 composites exhibited a crystal structure and phase composition by X-ray diffraction analysis. The different morphologies of the Al/Fe2O3 composites were also observed through scanning electron microscopy and transmission electron microscopy. It was found that the rather simple electrospinning method used to prepare the morphology-controlled Al/Fe2O3 composites may have the potential for preparation of propellants, explosives, and pyrotechnics in the future.

关键词： surfactant prepare calcination polyvinyl dispersed pyridine attributed metastable fabrication coated