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Science china(Information Sciences) 2012年第1期55卷 90-97页

作者： RAO Lei1&YANG DongXiao1,2 1Department of Information Science and Electronic Engineering,zhejiang university,hangzhou 310027,china 2Research Center for Terahertz Technology,zhejiang university,hangzhou 310027,china 1. Department of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China2. Research Center for Terahertz Technology Zhejiang University Hangzhou 310027 China

Terahertz transmission spectra through both single-layered and double-layered sub-wavelength metal hole arrays were calculated using rigorous mode-matching *** dispersion relations of the single-layered and double-layered metal hole arrays were obtained by FDTD *** are three anomalous peaks in the spectrum of the double-layered metal hole array,which arise from the three surface electromagnetic modes appearing in the dispersion *** comparing the transmission spectra and the dispersion relations of the single-layered and double-layered metal hole arrays,it was found that the two surface electromagnetic modes at higher frequencies are introduced by the single-layered metal hole array,while the one at lower frequencies is introduced by the double-layered metal hole *** validity of the analysis was qualitatively verified by the experimental *** structure can be finely designed for potential applications,such as wideband filtering.

关键词： surface electromagnetic modes double-layered metal hole array terahertz

COMPUTING EIGENVECTORS OF NORMAL MATRICES WITH SIMPLE INVERSE ITERATION

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Journal of Computational Mathematics 2003年第5期21卷 657-670页

作者： Zhen-yue Zhang Tiang-wei Ouyang (Department of Mathematics, zhejiang university, Yuquan Campus, hangzhou 310027, china) Department of Mathematics Zhejiang University Yuquan Campus Hangzhou 310027

It is well-known that if we have an approximate eigenvalue A of a normal matrix A of order n, a good approximation to the corresponding eigenvector u can be computed by one inverse iteration provided the position, say kmax, of the largest component of u is known. In this paper we give a detailed theoretical analysis to show relations between the eigenvector u and vector Xk, k = 1, … ,n, obtained by simple inverse iteration, i.e., the solution to the system (A - I)x = ek with ek the kth column of the identity matrix I. We prove that under some weak conditions, the index kmax is of some optimal properties related to the smallest residual and smallest approximation error to u in spectral norm and Probenius norm. We also prove that the normalized absolute vector v = |u|/||u|| of u can be approximated by the normalized vector of (||x1||2, … ||xn||2)T- We also give some upper bounds of |u(k)| for those 'optimal' indexes such as Fernando's heuristic for kmax without any assumptions. A stable double orthogonal factorization method and a simpler but may less stable approach are proposed for locating the largest component of u.

关键词： Eigenvector Inverse iteration Accuracy Error estimation.

Method for determining effective flame emissivity in a rotary kiln incinerator burning solid waste

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Journal of zhejiang university-Science A(Applied Physics & Engineering) 2012年第12期13卷 969-978页

作者： Jin-cai DU1,2,Qun-xing HUANG1,Jian-hua YAN1 (1State Key Laboratory of Clean Energy Utilization,zhejiang university,hangzhou 310027,china) (2School of Aeronautics and Astronautics,zhejiang university,hangzhou 310027,china) 1. State Key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou 310027 China 2. School of Aeronautics and Astronautics Zhejiang University Hangzhou 310027 China

Temperature is the most important parameter for the improvement of combustion efficiency and the control of *** order to obtain accurate flame temperatures in a rotary kiln incinerator using non-intrusive thermographic method,the effective flame emissivity was studied.A combined narrow-and wide-band model and Mie scattering method were used to calculate the radiative properties for gases and fly-ash particles under different combustion *** effects of the air/waste ratio and fly-ash particles on the effective flame emissivity were *** results of numerical calculations showed that the effective emissivity decreased from 0.90 to 0.80 when the air/waste ratio increased from 1.0 to 1.8,and the effect of the fly-ash particles was ignorable under the conditions discussed in this *** measurement results indicated that the accuracy of the thermographic temperature measurements improved significantly if the setting of the flame emissivity was adjusted according to the air/waste ratio.

关键词： Thermographic temperature measurement Effective flame emissivity Rotary kiln incinerator Air/waste equivalenceratio

analysisES OF GENE EFFECTS ON SOME COCOON CHARACTERS IN SILKWORM MORIL

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生物数学学报 1994年第4期9卷 10-17页

作者： Duan Jialong Zhu Jun (Anhui Agricultulal university,Hefei 230061,Anhui)(Zhejia Agricultural Uuiversity,hangzhou 310029,zhejiang)

*** of genetic variance and covariance for individual characters showed that cocoon weight was controlled by both gene direct effect and maternal effect;Cocoon shell weight was controlled by gene direct effect mainly;Cocoon shell ratio was mainly due to maternal effect and se x-linked *** of genetic covariance components of each pair of ch aracters indicated that there were high significant positive relationships among most of genetic effects except maternal additive effect in cocoon weight and cocoon shell *** was a high positive relationship idirect effect between cocoon weight and cocoon shell ratio,but in cytop lasm effect and maternal effect were high negative relationships between *** there were high positive relationships in direct effect and maternal dominance between cocoon shell weight and cocoon shell *** of gene effects pointed out that sex-chromosome effects （Σi8=1Lii） on cocoon weight and cocoon shell weight both were lar ger positive values,that means cocoon weight and cocoon shell weight of females are generally higher than those of males in Silkworm. Standardized donmiance directions of direct effects on cocoon weight and cocoon shell weight were high positive values,but standardized domiance directieon of maternal effects on both of them were high negative values,it showed the two characters had larger heterosis in F1 generation and depressed in F2 ***-chromosome effect （Σi8=1Lii） on cocoon she11 ratio was high negative value,explaining that females usually have lower cocoon shell ratio than *** domiance directions of direct effect and maternal effect on cocoon shell ratio were not significant,predicting that the heterosis of cocoon shell ratio in F1 generation is not obvious comparing to cocoon weight and cocoon shell weight.

关键词： Silkworm Cocoon characters Genetical analysis

Analytical solution and semi-analytical solution for anisotropic functionally graded beam subject to arbitrary loading

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Science china(Physics,Mechanics & Astronomy) 2009年第8期52卷 1244-1256页

作者： HUANG DeJin1,2,DING HaoJiang1 & CHEN WeiQiu3 1 Key Laboratory of Soft Soils and Geoenvironmental Engineering,Ministry of Education,zhejiang university,hangzhou 310027,china 2 Faculty of Engineering,Ningbo university,Ningbo 315211,china 3 Department of Engineering Mechanics,zhejiang university,hangzhou 310027,china Key Laboratory of Soft Soils and Geoenvironmental Engineering Ministry of Education Zhejiang University Hangzhou 310027 China Faculty of Engineering Ningbo University Ningbo 315211 China Department of Engineering Mechanics Zhejiang University Hangzhou 310027 China

Analytical and semi-analytical solutions are presented for anisotropic functionally graded beams subject to an arbitrary load,which can be expanded in terms of sinusoidal *** plane stress problems,the stress function is assumed to consist of two parts,one being a product of a trigonometric function of the longitudinal coordinate(x) and an undetermined function of the thickness coordinate(y),and the other a linear polynomial of x with unknown coefficients depending on *** governing equations satisfied by these y-dependent functions are *** expressions for stresses,resultant forces and displacements are then deduced,with integral constants determinable from the boundary *** the analytical solution is derived for the beam with material coefficients varying exponentially or in a power law along the thickness,the semi-analytical solution is sought by making use of the sub-layer approximation for the beam with an arbitrary variation of material parameters along the *** present analysis is applicable to beams with various boundary conditions at the two *** numerical examples are presented for validation of the theory and illustration of the effects of certain parameters.

关键词： anisotropic material functionally graded arbitrary loading stress function analytical solution semi-analytical solution

Surface investigation on Upilex-S polymide film iradiated by vacuum ultraviolet radiation

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Rare Metals 2007年第S1期26卷 168-174页

作者： LIU Yuyan1),GONG Xianyun2),WAN Zhimin3),and DU Xingwen4.1) Department of Applied Chemistry,Harbin Institute of Technology,Harbin 150001,china 2) Department of Life Science and Chemistry,Harbin university,Harbin 150001,china 3) analysis and {4. Center,Harbin Institute of Technology,Harbin 150001,china 4. Center for Composite Materials,Harbin Institute of Technology,Harbin 150001,china Harbin Inst Technol Dept Appl Chem Harbin 150001 Peoples R China Harbin Univ Dept Life Sci & Chem Harbin 150001 Peoples R China Harbin Inst Technol Ctr Anal & Measurement Harbin 150001 Peoples R China Harbin Inst Technol Ctr Composite Mat Harbin 150001 Peoples R China

Vacuum ultraviolet radiation of Upilex-S polyimide film 25 μm thick was performed using a gas jet type of vacuum ultraviolet simulator which gives unfixed wavelength from 5 nm to 200 *** redeposited on the films were observed and the nanoparticles formed on the surface consist mainly of carbon *** in the composition and the chemical characteristics of film surface after radiation were identified by X-ray photoelectron spectroscopy(XPS).Relative O content in the radiated area was found to be higher,while N content was lower than in the pristine *** indicates that Upilex-S polyimide film releases N atoms as volatile *** the C1s,O1s envelopes were fitted using Multipak Spectrum *** surface morphologies on iradiated area were examined by Atomic Force Microscope(AFM).Pieces of radiant products protrude from the eradiated surface,leading to considerable roughness for the iradiated *** the surface transmittance of Upilex-S film after radiation reduces.

关键词： vacuum ultraviolet radiation Upilex-S polyimide film

Electrochemical properties of some cobalt antimonides as anode materi-als for lithium- ion batteries

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Rare Metals 2003年第4期22卷 298-303页

作者： ZHAO Xinbing, CAO Gaoshao, ZHANG Lijuan, and XIE JianDepartment of Materials Science and Engineering, zhejiang university, hangzhou 310027, china Department of Materials Science and Engineering Zhejiang University Hangzhou 310027

Some cobalt antimonides have been prepared and studied as the candidate anodematerials for lithium ion batteries. Reversible capacities of 4.4.4.3 and 54. mA.h.g^(-1) weremeasured at the first cycle for as-solidified CoSb_2, CoSb_3 and annealed CoSb_3 respectively. A lowlithium ions diffusion coefficient in the order of 10^(16) m^2.s^(-1) was estimated from thecoulometric titration measurements in the annealed CoSb_3 electrode. It was found that theelectrochemical properties of fine powders are significantly better than coarse powders. However theSEM picture shows that the nano-sized CoSb_3 powders gathered to larger granules, which worsenssomewhat the capacity retention of the nano-sized materials, although the volume capacities of theannealed and ball milled CoSb_3 remain near twice of that of graphite after 50 cycles.

关键词： Electrochemistry cobalt antimonides electrochemical analysis anodematerials lithium-ion batteries

STEREOCHEMICAL CONTROL IN PROPYLENE POLYMERIZATION CATALYZED BY UNBRIDGED METALLOCENE CATALYSTS

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Chinese Journal of Polymer Science 2001年第4期19卷 407-413页

作者： Yin-bang Zhu Zhi-qiang Fan Tariq Yasin Lin-xian Feng Department of Polymer Science and Engineering zhejiang university hangzhou 310027, china zhejiang Univ Dept Polymer Sci & Engn Hangzhou 310027 Peoples R China

Two unbridged metallocene catalysts, bis(2,4.7-trimethylindenyl)zirconium dichloride (met-I) and bis(2,4.6-trimethylindenyl)zirconium dichloride (met-II), which are different in the position of substituents on the six-membered ring of the indenyl ligands were synthesized. The effect of substituents in the two metallocenes on the propylene polymerization was studied in the presence of methylaluminoxane (MAO) and triisobutylaluminium (TIBA). From the analysis of microstructure determined by C-13-NMR, it was demonstrated that the polymers produced by met-II have higher [mmmm] isotactic sequences than that of met-I. Using a mechanism based on model statistical analysis, it was found that chain-end model was dominant for met-I. However, met-II obeys the concurrent two-sites model during polymerization, which can be attributed to the existence of 'racemic-like' conformer in its system.

关键词： unbridged metallocene propylene polymerization elastomeric polypropylene stereochemical mechanism

Hydriding-dehydriding properties of Mg_2Ni alloy modified by ball-milling in tetrahydrofuran

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Rare Metals 2004年第2期23卷 138-142页

作者： CHEN Changpin WANG Wei CHEN Yun CHEN Lixin WANG Qidong Department of Materials Science and Engineering, zhejiang university hangzhou 310027, china Department of Materials Science and Engineering Zhejiang University Hangzhou 310027 China

A new approach of ball-milled Mg_2Ni in tetrahydrofuran (THF) to improve thehydriding kinetics of Mg_2Ni alloy is suggested and studied. It is found that the modified alloydisplayed the improved activity for hydriding even at relatively low temperature (e.g., 323-373 K).In the case of the sample milled in THF for 20 h, the hydrogen content (mass fraction) reaches 1.6 %at 323 K, 2.1% at 34. K and 3.4. at 4.8 K, respectively. The use of THF during grinding led to thechange of the structure, which is reflected by the broadening and weakening of the diffraction peaksin the XRD spectra. The XPS analysis shows that Mg (2s) binding energy peak of Mg_2Ni aftermodification shifted from a lower binding energy to a higher one, indicating the charge transferencebetween Mg and THF and the formation of catalytically active electron donor-acceptor (EDA)complexes on the surface of modified Mg_2Ni alloy.

关键词： metal materials Mg_2Ni alloy ball-milling tetrahydrofuran hydriding-dehydriding property

Inheritance and Expression of Potato Proteinase Inhibitor Gene II(pinII)in Transgenic Rice

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Journal of Integrative Agriculture 2003年第7期 25-32页

作者： CHENG Zhong-yi and XUE Qing-zhong(Department of Agronomy, Agriculture and Biotechnology College, zhejiang university, hangzhou 310029, P.R.china)

The inheritance and expression of bar gene and pinII gene were studied in three transgenic rice lines and their F2 hybrid populations, which were created through hybridization with a PGMS line, ZAU11S. By Basta painting, PCR analysis and determining of the inhibitory trypsin activity, the results show that bar gene and pinII gene in rice F2 population fit the simple Mendel’s low of inheritance and close linkage, but a few plants in F2 have not sufficiently expressed. The wound inducible pin II gene has an expression regulated spatially and temporally, and the signal transduction pathway is not only upward, but also downward. The inducible expression of pin II in different rice transgenic lines is not completely coincident.

关键词： Transgenic rice pin II gene bar gene Inheritance Inducible expression