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Semi-analytical weight function method for center-cracked circular disk subjected to diametral compression

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Journal of Central South university of Technology 2001年第2期8卷 99-104页

作者： CHEN Feng, SUN Zong qi, XU Ji cheng (The key laboratory of Nonferrous Metal Materials science and Engineering, Central South university, Changsha 410083, china) 1. The key laboratory of Nonferrous Metal Materials science and Engineering Central South University 410083 Changsha China

Büeckner Rice weight function method was used to analyse mixed mode fracture of center cracked circular disk subjected to uniaxial compression. Based on Wu Carlsson procedure semi analytical modes Ⅰ and Ⅱ weight functions were derived from corresponding reference displacement fields and stress intensity factors calculated by finite element method. Normalized mode Ⅰ and mode Ⅱ stress intensity factors, f Ⅰ, f Ⅱ , were derived from the obtained semi analytical weight functions. The results were then fitted into polynomials, the precision is within 0.5%. It is interesting to note that when the inclined angle θ of a crack is less than 15°, the f Ⅰvalues are positive. when θ =15°, the f Ⅰ values are positive for the crack length a varying from 0.1 to 0.7, but when a =0.8, the f Ⅰ takes the negative value -0.51. When θ >15°, all the f Ⅰ values become negative, which denotes that the compression shear mode is achieved at crack tips. These results are very useful in the investigation of mixed mode fracture of brittle materials.

关键词： weight function stress intensity factor compression center cracked circular disk

Design and analysis on a Gires-Tournois resonator based interleaver

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Optoelectronics Letters 2009年第1期5卷 51-53页

作者：王秀琳黄文财张宇蔡志平 Department of Physics Jimei University Department of Physics Xiamen University Department of Electronic Engineering Xiamen University

A flat-top interleaver,in which a mirror on one arm of the Michelson interferomefer is replaced by a G-T resonator,is *** the interleaver,the parameters including the channel spacing of 50 GHz,ripple less than 0.05 dB,-0.5 dB passband of 43 GHz(86% of the spacing),-30 dB stopband of 42 GHz(84% of the spacing),and a channel isolation higher than 40 dB,are achieved.

关键词： Design and analysis on a Gires-Tournois resonator based interleaver THz

Revisiting the difference of temperature-rate relationships of autotrophic and heterotrophic planktona meta-analysis on intraspecific and interspecific relationships

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Revisiting the difference of temperature-rate relationships ...

Ⅱ conjugation in the butadiene

中国藻类学会第八次会员大会暨第十六次学术讨论会

作者： Binzhang Chen 1,State key laboratory of Marine Environmental science,Environmental science Research Center,xiamen university,361.05 xiamen,Fujian,china

＜正＞I revisit the possible difference of temperature-growth rate relationships between autotrophic and heterotrophic *** a meta-analysis on published studies on temperature and growth rates of autotrophic and heterotrophic plankton under resource-replete conditions,I find that,while significant heterogeneity exists among phylogenetic groups,the mean temperature coefficient of intraspecific growth rates of phytoplankton defined as the activation energy in the Arrhenius equation is not significantly different from the ’canonic’ 0.65 eV predicted by the Metabolic Theory of Ecology,but the mean activation energy of interspecific growth rates of phytoplankton is close to 0.32 eV predicted *** difference of the mean activation energy of intraspecific phytoplankton growth rates from theoretical derivation might result from the widespread C02 concentrating mechanisms in phytoplankton,which minimizes the problem of *** difference of the activation energy between intraspecific versus interspecific phytoplankton growth rates might reflect the strategy of cold-adaptation in phytoplankton,but not in heterotrophic plankton,for which the mean activation energies of both intraspecfic and interspecific growth rates are close to 0.65 *** mean activation energies of intraspecific ingestion and clearance rates of heterotrophic plankton are also insignificantly different from 0.65 *** results suggest that when investigating the response of plankton systems to increasing temperature,the knowledge of the changes in community structure is important.

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Chinese Journal of Chemistry 1995年第1期13卷 27-32页

作者： MO, Yi-Rong WU, Wei ZHANG, Qian-ErDepartment of Chemistry, xiamen university, xiamen, Fujian 361.05, china

The π electronic delocalization in trans-C4H6 and cis-C4H6 has been investigated in the frame of ab initio valence bond theory with 6-31G basis set. The result shows that the Csp2-Csp2 single bond length (1.506 A) is only about 0.024 A shorter than the Csp3-Csp3 bond, thus the central bond length shortening would be mainly due to π conjugation. The theoretical resonance energies of the trans-C4H6 and cis-C4H6 are 8.48 and 7.44 kcal/mol, respectively.

关键词： Butadiene valence bond delocalization.

Distribution and germination of viable diatom resting stage cells in sediments of the East china Sea

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Acta Oceanologica Sinica 2010年第5期29卷 121-128页

作者： ZHANG Yuyu LU Songhui ZHANG Chuansong GAO Yahui key laboratory of Ministry of Education for Coast and Wetland Ecosystems School of Life Sciences Xiamen University Xiamen 361005 China Research Center for Harmful Algae and Aquatic Environment Jinan University Guangzhou 510632 China College of Life science South China Normal University Guangzhou 510631 China College of Chemistry and Chemical Engineering Ocean University of China Qingdao 266100 China

The abundance and temporal patterns of viable diatom resting stage cells in sediments of the East china Sea in 2006 have been *** abundance of viable resting stages was enumerated with the most probable number（MPN） ***,25 diatom species（including varieties） belonging to 16 genera were *** resting stage cells were common,on the order of 103 to 106 cells/g dry *** abundant taxa included Skeletonema marina,***,Chaetoceros curvisetus and Thalassiosira spp.,with Skeletonema accounting for 83.3% of the *** effects of temperature（10,15,20,25 ℃）,salinity（20,25,30,35 psu） and light intensity（0,300,4 000,8 000 lux） on the germination of resting stages in sediment samples were also *** results showed that light intensity had a significant positive effect on the germination of diatom resting stage cells（p 〈0.01） and that diatoms could not germinate in *** and salinity had no noticeable effects on the *** present study suggests that there are abundant diatom resting cells in sediments of the East china Sea,which could serve as a ＂seed bank＂ in the phytoplankton population succession and contribute to the initiation of algal blooms.

关键词： diatom germination MPN resting stages seed bank sediment

Enrichment mechanisms of rare earth elements in marine hydrogenic ferromanganese crusts

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science china Earth sciences 2011年第2期54卷 197-203页

作者： JIANG XueJun1,2,LIN XueHui1,2,YAO De3,4 & GUO WeiDong5 1 key laboratory of Marine Oil and Gas Resources and Marine Environment,Ministry of Land and Resources,Qingdao 266071,china 2 Qingdao Institute of Marine Geology,china Geological Survey,Qingdao 266071,china 3 Institute of Resources and Environment,Shandong university of Technology,Zibo 255049,china 4 Institute of Oceanology,Chinese Academy of sciences,Qingdao 266071,china 5 Department of Oceanography,xiamen university,xiamen 361.05,china 1. key laboratory of Marine Oil and Gas Resources and Marine Environment Ministry of Land and Resources Qingdao 266071 China2. Qingdao Institute of Marine Geology China Geological Survey Qingdao 266071 China3. Institute of Resources and Environment Shandong University of Technology Zibo 255049 China4. Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China5. Department of Oceanography Xiamen University Xiamen 361005 China

A series of selective extraction experiments were conducted on marine hydrogenic ferromanganese crusts from the seamount near the Line Island to investigate the distribution of rare earth elements （REEs） and the mechanisms of combination between REEs and the hydrogenic ferromanganese crusts. The enrichment of REEs in hydrogenic ferromanganese crusts is attributed mainly to the mineral or oxide/hydroxide of the crust rather than the growth environment. The REEs are present mainly in amorphous ferric oxide/hydroxide rather than in 6-MnO2. Amorphous ferric oxide/hydroxide preferentially combines free REE3＋, while 6-MnO2 combines the REE-carbonate complexes in modern seawater. The REEs in seawater are combined more strongly with amorphous ferric oxide/hydroxides than with 6-MnO2. The positive Ce anomaly in hydrogenic ferromanganese crusts results from the oxidation of soluble Ce3＋ to insoluble Ce4＋ by the actively soluble oxygen of the bottom current rather than by the oxidation of δ-MnO2.

关键词： rare earth elements hydrogenic ferromanganese crust selective extraction experiment geochemistry combinationmechanism

Thermodynamic database of the phase diagrams in the Mg-Al-Zn-Y-Ce system

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Rare Metals 2006年第5期25卷 441-447页

作者： LIU Xingjun WANG Cuiping WEN Mingzhong CHEN Xing PAN Fusheng Department of Materials science and Engineering Xiamen University Xiamen 361005 China College of Materials science and Engineering Chongqing University Chongqing 400045 China

The Mg-Al-Zn-Y-Ce system is one of the key systems for designing high-strength Mg alloys. The purpose of the present article is to develop a thermodynamic database for the Mg-Al-Zn-Y-Ce multicomponent system to design Mg alloys using the calculation of phase diagrams （CALPHAD） method, where the Gibbs energies of solution phases such as liquid, fcc, bcc, and hcp phases were described by the subregular solution model, whereas those of all the compounds were described by the sublattice model. The thermodynamic parameters describing Gibbs energies of the different phases in this database were evaluated by fitting the experimental data for phase equilibria and thermodynamic properties. On the basis of this database, a lot of information concerning stable and metastable phase equilibria of isothermal and vertical sections, molar fractions of constituent phases, the liquidus projection, etc., can be predicted. This database is expected to play an important role in the design of Mg alloys.

关键词： thermodynamic database CALPHAD method phase diagram Mg-Al-Zn-Y-Ce system magnesium alloys

Implementation of a multiple round quantum dense coding using nuclear magnetic resonance

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science china(Physics,Mechanics & Astronomy) 2005年第6期48卷 706-715页

作者： ZHANG Jingfu1, XIE Jingyi2, WANG Chuan1, DENG Zhiwei3, LU Zhiheng4, & LONG Guilu1,5 1. key laboratory For Quantum Information and Measurements of MOE, Department of Physics, Tsinghua university, Beijing 100084,china 2. Department of Materials science and Engineering, Beijing Normal university, Beijing 100875, china 3. Testing and analytical Center, Beijing Normal university, Beijing 100875,china 4. Department of Physics, Beijing Normal university, Beijing 100875, china 5. key laboratory For atomic and Molecular Nanosciences, Tsinghua university, Beijing 100084,china 1. key laboratory For Quantum Information and Measurements of MOE Department of Physics Tsinghua University 100084 Beijing China 2. Department of Materials science and Engineering Beijing Normal University 100875 Beijing China 3. Testing and analytical Center Beijing Normal University 100875 Beijing China 4. Department of Physics Beijing Normal University 100875 Beijing China 5. key laboratory For Atomic and Molecular Nanosciences Tsinghua University 100084 Beijing China

A multiple round quantum dense coding scheme based on the quantum phase estimation algorithm is proposed and implemented in a three qubit nuclear magnetic resonance (NMR) quantum computer. Using an m + 1 qubit system, Bob can transmit one of 2m+1 messages to Alice, through manipulating only one qubit and exchanging it between Alice and Bob for m rounds. The information capacity is enhanced to m + 1 bits as compared to m bits in a classical scheme. The scheme has been demonstrated in NMR system, and the experimental results show a good agreement between theory and experiment.

关键词： quantum dense coding, multiple round, nuclear magnetic resorance

Rhodamine B doped silica nanoparticle labels for protein microarray detection

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science china Chemistry 2010年第4期53卷 747-751页

作者： WANG Ying1, LI ZhongHui1, ZHONG WenYing2, LI Hui2, XU DanKe1 & CHEN HongYuan1 1key laboratory of analytical Chemistry for Life science, Ministry of Education School of Chemistry and Chemical Engineering, Nanjing university, Nanjing 210093, china 2Department of analytical Chemistry, china Pharmaceutical university, Nanjing 210009, china 1. key laboratory of analytical Chemistry for Life science Ministry of Education School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China2. Department of Analytical Chemistry China Pharmaceutical University Nanjing 210009 China

A core-shell Rhodamine B-doped SiO2 nanoparticle was synthesized and its fluorescent intensity was found to be 1000 times higher than that of individual Rhodamine B molecule. The doped nanoparticles were further conjugated with streptavidin and the resulting nanoparticles were used in the detection of reverse-phase protein microarrays, in which human IgG of various concentrations was first immobilized on aldehyde-modified glass slides and then biotinlyated goat anti human IgG as well as the labeled nanoparticles were sequentially conjugated. The calibration curve is linear over the range from 800 fg to 500 pg and the limit of detection is 100 fg, which is 8 times lower than that of streptavidin-labeled Cy3 fluorescent dyes. The dyedoped SiO2 nanoparticles show potentials for the protein array detection.

关键词： Rhodamine B SiO2 nanoparticles protein detection protein microarrays