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Effects of Doped Elements on Electrochemical Performance of Ni(OH)_2 Materials

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Chemical Research in Chinese Universities 2007年第4期23卷 452-455页

作者： lee Chang-sheng School of Chemical Engineering and Technology Tianjin University

High energy ball milling （HEBM） method was applied to synthesize Ni （OH）2 with different doped elements sub-stitution for Ni^2＋. The morphology, structure and electrochemical behavior of prepared powders were studied. The re-suits reveal that all the synthesized Ni（OH）2 particles were in sub-micron sizes and greatly agglomerated. Co-, Mg-,Fe- or Mn-doped Ni （OH） 2 was of β-phase with 0.400-0.500 nm crystal interlayer distance, while A1- and Zn-doped products displayed a-phase with larger crystal interlayer spaces. The electrochemical mechanisms of synthe-sized Ni（OH）2 electrodes were discussed by EIS spectra. The specific capacity of Co-doped Ni （OH）2 is 245 mA·h · g^-1, i. e. , 60 mA· h · g^-1 higher than that of Al-doped electrode, which has the highest discharging plat-form of a mid-voltage of 1.30 V.

关键词： Nickel hydroxide High energy ball milling method Metallic ion adulteration Electrochemical discharging capacity

Control of petroleum-hydrocarbon contaminated groundwater by intrinsic and enhanced bioremediation

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Journal of Environmental Sciences 2010年第6期22卷 864-871页

作者： Chih-Ming Kao Rao Y.Surampalli Mu-sheng lee Institute of Environmental Engineering "National" Sun Yat-Sen University U.S.Environmental Protection Agency Environmental Protection Bureau Kaohsiung City Government

In the first phase of this study, the effectiveness of intrinsic bioremediation on the containment of petroleum hydrocarbons was evaluated at a gasoline spill site. Evidences of the occurrence of intrinsic bioremediation within the BTEX （benzene, toluene, ethylbenzene, and xylenes） plume included （1） decreased BTEX concentrations; （2） depletion of dissolved oxygen （DO）, nitrate, and sulfate; （3） production of dissolved ferrous iron, methane, and CO2; （4） deceased pH and redox potential; and （5） increased methanogens, total heterotrophs, and total anaerobes, especially within the highly contaminated areas. In the second phase of this study, enhanced aerobic bioremediation process was applied at site to enhance the BTEX decay rates. Air was injected into the subsurface near the mid-plume area to biostimulate the naturally occurring microorganisms for BTEX biodegradation. Field results showed that enhanced bioremediation process caused the change of BTEX removal mechanisms from anaerobic biodegradation inside the plume to aerobic biodegradation. This variation could be confirmed by the following field observations inside the plume due to the enhanced aerobic bioremediation process：（1） increased in DO, CO2, redox potential, nitrate, and sulfate, （2） decreased in dissolved ferrous iron, sulfide, and methane, （3） increased total heterotrophs and decreased total anaerobes. Field results also showed that the percentage of total BTEX removal increased from 92% to 99%, and the calculated total BTEX first-order natural attenuation rates increased from 0.0092% to 0.0188% per day, respectively, after the application of enhanced bioremediation system from the spill area to the downgradient area （located approximately 300 m from the source area）.

关键词： petroleum hydrocarbon groundwater natural attenuation intrinsic bioremediation

Mimetic Preparation of Analogues of Territrem B, A Potent Acetylcholinesterase Inhibitor

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Chinese Chemical Letters 2000年第12期11卷 1045-1048页

作者： Yu ZHAO Yuan Ling KU Shoei sheng lee Laboratory of Phytochemistry Kunming Institute of BotanyChinese Academy of SciencesKunming 650204 School of Pharmacy College of MedicineNational Taiwan UniversityTaipei 10018

A mimetic synthesis of a potent acetylcholinesterase inhibitor, Territrem B, was carried out from the naturally occurring jujubosides. The anti-AChE activity of the product, which possesses the 2-en-1-one pharmacophore and the aromatic ring, was measured. The aromatic ring moiety seemed to be less influencing when comparing with the 2-en-1-one moiety.

关键词： acetylcholinesterase inhibitor territrem B analogues jujubosides

Preparation of AChE Inhibitors From Jujubogenin

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Chinese Chemical Letters 2000年第8期11卷 671-674页

作者： Yu ZHAO Yuan Ling KU Shoei sheng lee Laboratory of Phytochemistry Kunnming Institute of BotanyChinese Academy of SciencesKunming 650204 School of Pharmacy College of MedicineNational Taiwan UniversityTaipei 10018

A dammarane derivative dihydrojujubogenin-2-en-1-one, which possesses a skeleton and pharmacophore partially similar to those of Territrem B, a potent AChE inhibitor, was synthesized via three different paths. The ant... 详细信息

关键词： Alzheimer disease (AD) acetylcholinesterase AChE inhibitor pharmaceutical chemistry jujubogenin Territrem B analogues

Tunable multiband terahertz metamaterials using a reconfigurable electric split-ring resonator array

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Light(Science & Applications) 2014年第1期3卷 211-218页

作者： Fusheng Ma Yu-sheng Lin Xinhai Zhang Chengkuo lee Department of Electrical and Computer Engineering National University of SingaporeSingapore 117576Singapore Institute of Materials Research and Engineering A*STARSingapore 117602Singapore

We demonstrate micromachined reconfigurable metamaterials working at multiple frequencies simultaneously in the terahertz *** proposed metamaterial structures can be structurally reconfigured by employing flexible microelectromechanical system-based cantilevers in the resonators,which are designed to deform out of plane under an external *** proposed metamaterial structures provide not only multiband resonance frequency operation but also polarization-dependent *** kinds of metamaterials are investigated as electric split-ring resonator(eSRR)arrays with different positions of the *** moving the position of the split away from the resonator’s center,the eSRR exhibits anisotropy,with the dipole resonance splitting into two *** dipole–dipole coupling strength can be continuously adjusted,which enables the electromagnetic response to be tailored by adjusting the direct current(DC)voltage between the released cantilevers and the silicon *** observed tunability of the eSRRs is found to be dependent on the polarization of the incident terahertz *** polarization-dependent tunability is demonstrated by both experimental measurements and electromagnetic simulations.

关键词： MEMS reconfigurable metamaterials split-ring resonator terahertz tunability

A Facile Synthesis of Monodisperse Au Nanoparticles and Their Catalysis of CO Oxidation

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Nano Research 2008年第3期1卷 229-234页

作者： sheng Peng Youngmin lee Chao Wang Hongfeng Yin sheng Dai Shouheng Sun Department of Chemistry Brown UniversityProvidenceRhode Island 02912USA Chemical Sciences Division Oak Ridge National LaboratoryTennessee 37831USA

Monodisperse Au nanoparticles(NPs)have been synthesized at room temperature via a burst nucleation of Au upon injection of the reducing agent t-butylamine-borane complex into a 1,2,3,4-tetrahydronaphthalene solution of HAuCl4·3H2O in the presence of *** as-synthesized Au NPs show size-dependent surface plasmonic properties between 520 and 530 *** adopt an icosahedral shape and are polycrystalline with multiple-twinned *** deposited on a graphitized porous carbon support,the NPs are highly active for CO oxidation,showing 100%CO conversion at-45°C.

关键词： Nanoparticle synthesis Au nanoparticles catalysis CO oxidation

IDSH: An Improved Deep Supervised Hashing Method for Image Retrieval

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Computer Modeling in Engineering & Sciences 2019年第11期121卷 593-608页

作者： Chaowen Lu Feifei lee Lei Chen sheng Huang Qiu Chen School of Optical-Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghai200093China Major of Electrical Engineering and Electronics Graduate School of EngineeringKogakuin University1-24-2Nishi-shinjukuSinjuku-kuTokyo163-8677Japan

Image retrieval has become more and more important because of the explosive growth of images on the *** image retrieval methods have limited image retrieval performance due to the poor image expression abhility of visual feature and high dimension of *** is a widely-used method for Approximate Nearest Neighbor(ANN)search due to its rapidity and ***,Convolutional Neural Networks(CNNs)have strong discriminative characteristics which are used for image *** this paper,we propose a CNN architecture based on improved deep supervised hashing(IDSH)method,by which the binary compact codes can be generated *** main contributions of this paper are as follows:first,we add a Batch Normalization(BN)layer before each activation layer to prevent the gradient from vanishing and improve the training speed;secondly,we use Divide-and-Encode Module to map image features to approximate hash codes;finally,we adopt center loss to optimize *** experimental results on four large-scale datasets:MNIST,CIFAR-10,NUS-WIDE and SVHN demonstrate the effectiveness of the proposed method compared with other state-of-the-art hashing methods.

关键词： Image retrieval convolutional neural network hash functions center loss

EXPERIMENTAL STUDY OF VENTILATED SUPERCAVITIES WITH A DYNAMIC PITCHING MODEL

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Journal of Hydrodynamics 2008年第4期20卷 456-460页

作者： lee Qi-tao XUE Lei-ping HE You-sheng Department of Engineering Mechanics Shanghai Jiaotong University Shanghai 200240 China

An investigation of the ventilated supercavitation for a supercavitating vehicle pitching up and down in the supercavity was carded out in a high-speed water tunnel. The emphasis is laid on the understanding of the interaction of the vehicle aft body with the cavity boundary. The flow characteristics were measured and the stability of supercaviting flow with different pitching frequencies and amplitudes was analyzed. In particular, the objectives of this study are to understand the effect of the impact upon the cavity distortion, and to quantify the impact process by investigating the evolution of the pressure inside the cavity and then the loads on the vehicle during the pitching motion. It is also shown that the evolution of the pressure detected in different,as inside the supercavity, is coherent and uniform during the periods of the pitching motion. This study is of direct relevance to reliable and accurate prediction of hydrodynamic loads associated with the slamming and impact on supercavitating vehicles.

关键词： supercavitating flow pitching motion water tunnel ventilated cavitation impact

Approximation of Nearest Common Fixed Point of Nonexpansive Mappings in Hilbert Spaces

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Acta Mathematica Sinica,English Series 2007年第10期23卷 1889-1896页

作者： Shi sheng ZHANG H.W. JOSEPH lee Chi Kin CHAN Department of Mathematics Yibin University Yibin 644007 P. R. China Department of Mathematics Sichuan University Chengdu 610064 P. R. China Department of Applied Mathematics The Hong Kong Polytechnic University Hung Horn Kowloon Hong Kong P. R. China

The purpose of this paper is to study the convergence problem of the iteration scheme xn＋l = λn＋1y ＋（1 - λn＋1）Tn＋1xn for a family of infinitely many nonexpansive mappings T1, T2,... in a Hilbert space. It is proved that under suitable conditions this iteration scheme converges strongly to the nearest common fixed point of this family of nonexpansive mappings. The results presented in this paper extend and improve some recent results.

关键词： common fixed point family of nonexpansive mappings nearest point projection iterative scheme