• Title/Summary/Keyword: Qingdao University

검색결과 295건 처리시간 0.032초

DISTRIBUTION CHARACTERISTICS AND AFFECTING FACTORS OF SPRING HETEROTROPHIC BACTERIA IN BOHAI SEA

  • Bai, Jie;Li, Kuiran;Li, Zhengyan;Gao, Huiwang;Wu, Zengmao
    • 한국환경보건학회:학술대회논문집
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    • 한국환경보건학회 2001년도 Proceedings of the 3rd Annual Meeting of Yellow Sea Environment
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    • pp.6-10
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    • 2001
  • Distribution characteristics, variation patterns and affecting factors of hetorotrophic bacteria were studied from April to May 1999 in Bohai Sea by standard Acridine Orange epifluorescence microscopy (AO method). The biomass in surface waters showed a small day-night variation, varying from 0.13-2.51$\mu\textrm{m}$$.$dm$\^$-3/ with an average of 0.84 $\mu\textrm{m}$$.$dm$\^$-3/. The biomass in bottom waters showed, however, a large variation, changing from 0.15-4.18 $\mu\textrm{m}$$.$dm$\^$-3/ with an average of 1.36 $\mu\textrm{m}$$.$dm$\^$-3/. The peak values were obtained at 5 and 11 am. The bottom water biomass showed a significant correlation with particulate organic carbon (r=0.639, p<0.05). Heterotrophic bacteria showed high biomass in nearshore waters and low values in offshore areas with a high biomass zone around Yellow Sea river mouth, which was consistent with the distribution of nutrients. The vertical distribution of heterotrophic bacteria showed biomass in bottom waters was higher than in surface water. The biomass of heterotrophic bacteria in Bohai Sea was similar with that in other marine waters.

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State-of-charge Estimation for Lithium-ion Batteries Using a Multi-state Closed-loop Observer

  • Zhao, Yulan;Yun, Haitao;Liu, Shude;Jiao, Huirong;Wang, Chengzhen
    • Journal of Power Electronics
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    • 제14권5호
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    • pp.1038-1046
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    • 2014
  • Lithium-ion batteries are widely used in hybrid and pure electric vehicles. State-of-charge (SOC) estimation is a fundamental issue in vehicle power train control and battery management systems. This study proposes a novel model-based SOC estimation method that applies closed-loop state observer theory and a comprehensive battery model. The state-space model of lithium-ion battery is developed based on a three-order resistor-capacitor equivalent circuit model. The least square algorithm is used to identify model parameters. A multi-state closed-loop state observer is designed to predict the open-circuit voltage (OCV) of a battery based on the battery state-space model. Battery SOC can then be estimated based on the corresponding relationship between battery OCV and SOC. Finally, practical driving tests that use two types of typical driving cycle are performed to verify the proposed SOC estimation method. Test results prove that the proposed estimation method is reasonably accurate and exhibits accuracy in estimating SOC within 2% under different driving cycles.

Assessment and Correction of the Spectral Quality for the Savart Polarization Interference Imaging Spectrometer

  • Zhongyi Han;Peng Gao;Jingjing Ai;Gongju Liu;Hanlin Xiao
    • Current Optics and Photonics
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    • 제7권5호
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    • pp.518-528
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    • 2023
  • As an effective means of remotely detecting the spectral information of the object, the spectral calibration for the Savart polarization interference imaging spectrometer (SPIIS) is a basis and prerequisite of information quantification, and its experimental calibration scheme is firstly proposed in this paper. In order to evaluate the accuracy of the spectral information acquisition, the linear interpolation, cubic spline interpolation, and piecewise cubic interpolation algorithms are adopted, and the precision of the quadratic polynomial fitting is the highest, whose fitting error is better than 5.8642 nm in the wavelength range of [500 nm, 820 nm]. Besides, the inversed value of the spectral resolution for the monochromatic light is greater than the theoretical value, and the deviation between them becomes larger with the wavelength increasing, which is mainly caused by the structural design of the SPIIS, together with the rationality of the spectral restoration algorithm and the selection of the maximum optical path difference (OPD). This work demonstrates that the SPIIS has achieved high performance assuring the feasibility of its practical use in various fields.

The effect of mechanical inhomogeneity in microzones of welded joints on CTOD fracture toughness of nuclear thick-walled steel

  • Long Tan;Songyang Li;Liangyin Zhao;Lulu Wang;Xiuxiu Zhao
    • Nuclear Engineering and Technology
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    • 제55권11호
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    • pp.4112-4119
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    • 2023
  • This study employs the microshear test method to examine the local mechanical properties of narrow-gap welded joints, revealing the mechanical inhomogeneity by evaluating the microshear strength, stress-strain curves, and failure strain. On this basis, the influence of weld joints micromechanical inhomogeneity on the crack tip opening displacement (CTOD) fracture toughness is investigated. From the root weld layer to the cover weld layer, the fracture toughness at the center of the weld seam demonstrates an increasing trend, with the experimental and calculated CTOD values showing a good correspondence. The microproperties of the welded joints significantly impact the load-bearing capacity and fracture toughness. During the deformation process of the "low-matching" microregions, the plastic zone expansion is hindered by the surrounding microregion strength constraints, thus reducing the fracture toughness. In contrast, during the deformation of the "high-matching" microregions, the surrounding microregions absorb some of the loading energy, partially releasing the concentrated stress at the crack tip, which in turn increases the fracture toughness.

A NONLINEAR CONJUGATE GRADIENT METHOD AND ITS GLOBAL CONVERGENCE ANALYSIS

  • CHU, AJIE;SU, YIXIAO;DU, SHOUQIANG
    • Journal of applied mathematics & informatics
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    • 제34권1_2호
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    • pp.157-165
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    • 2016
  • In this paper, we develop a new hybridization conjugate gradient method for solving the unconstrained optimization problem. Under mild assumptions, we get the sufficient descent property of the given method. The global convergence of the given method is also presented under the Wolfe-type line search and the general Wolfe line search. The numerical results show that the method is also efficient.

INFLUENCE AND BlOCONCENTRATlON OF PETROLEUM HYDROCARBON ASSOCIATED WITH OIL ON AND BY PLANKTON IN A MESOCOSM EXPERIMENT OF EAST CHINA SEA

  • Shi, Xiaoyong;Wang, Xiulin;Jiang, Yu;Han, Xiurong
    • 한국환경보건학회:학술대회논문집
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    • 한국환경보건학회 2001년도 Proceedings of the 3rd Annual Meeting of Yellow Sea Environment
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    • pp.42-48
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    • 2001
  • A kinetic model was presented to estimate the uptake/release rate constants and thereafter, bioconcentration factor, $k_1$, $k_2$ and BCF (bioconcentration factor), for the uptake of PH by plankton were obtained. Implies that PH(petroleum hydrocarbon) caused no significant influence on the uptake of $N-NO_3$, but significant influence on that of $P-PO_4$. In addition, the application of kinetic model for the bioconcentration of volatile organic toxic compound by organism suggests that the uptake of PH by plankton was an important process for the environmental capacity of PH.

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Electrochemical and Spectroscopic Studies on the Interaction between DNA and the Product of Enzyme-catalyzed Reaction of OPD-H2O2-HRP

  • Niu, S.Y.;Zhang, S.S.;Ma, L.B.;Jiao, K.
    • Bulletin of the Korean Chemical Society
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    • 제25권6호
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    • pp.829-832
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    • 2004
  • The pure product of 2,3-diaminophenazine was prepared by the enzyme-catalyzed reaction of ophenylenediamine-$H_2O_2$-horseradish peroxidase and characterized by UV/Vis spectroscopy, IR spectroscopy and NMR spectroscopy. The electrochemical behaviour of 2,3-diaminophenazine on the glassy carbon electrode was studied. The interaction between 2,3-diaminophenazine and deoxyribonucleic acid was studied by cyclic voltammetry method and UV/Vis spectroscopy, which indicated that the interaction between them is intercalation. The influence of reacting time was also studied. The binding ratio of the 2,3-diaminophenazine-DNA complex is calculated to be 1 : 2 and the binding constant is to be $5.07{\times} 10^3L{\cdot}mol^{-1}$ at room temperature.

Cloning and Expression of cDNA Encoding a Cysteine Protease Inhibitor from Clamworm and Its Possible Use in Managing Anoplophora glabripennis Motschulsky (Coleoptera: Cerambycidae)

  • Li, Shengnan;Guo, Daosen;Zhao, Boguang;Ye, Jianling;Tian, Jie;Ren, Wenqing;Ju, Yunwei;Cui, Peng;Li, Ronggui
    • Journal of Microbiology and Biotechnology
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    • 제20권8호
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    • pp.1243-1250
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    • 2010
  • A cDNA encoding a cysteine protease inhibitor (CPI) was isolated from the cDNA library of clamworm Perinereis aibuhitensis Grube. The deduced amino acid sequence analysis showed that the protein had 51%, 48%, and 48% identity with Zgc:153129 from Danio rerio, cystatin B from Theromyzon tessulatum, and the ChainA, stefin B tetramer from Homo sapiens, respectively. The gene was cloned into the intracellular expression vector pET-15b and expressed in Escherichia coli. The recombinant CPI (PA-CPI) was purified by affinity chromatography on Ni-charged resin and ion-exchange chromatography on DEAE-Sepharose FF. The relative molecular mass of PA-CPI was 16 kDa as deduced by SDS-PAGE. Activity analysis showed that the recombinant protein could inhibit the proteolytic activity of papain. A constitutive and secretive expression vector was also constructed, and the cDNA encoding CPI was subcloned into the vector for extracellular expression. Western blotting analysis results showed that the PA-CPI was secreted into the medium. Bioassay demonstrated that E. coli DH5${\alpha}$ harboring pUC18ompAcat-CPI showed a significant difference in mortality to the Asian longhorned beetle Anoplophora glabripennis compared with untransformed E. coli DH5${\alpha}$ and control.