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101.
GenShuiCHENG JiWenHU MingQiuZHANG MingWeiLI DingShuXIAO MinZhiRONG 《中国化学快报》2004,15(12):1501-1504
The present work studies the electrical conduction performance of carbon blaak (CB) filled poly(ethylene oxide) (PEO) composites. The addition of CB leads to reduced matrix crystallinity as the fillers which are partly situated inside the lamellae and hinder the growth of PEO crystallites. As a result, the electrical percolation behavior is related with the matrix morphology. 相似文献
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设E是Hausdorff测度正有限的广义齐次自相似集,本文证明了s维Hausdorff测度是E上唯一的非扩张概率测度. 相似文献
104.
§ 1 IntroductionM-band wavelets are used in a lotof applications such asspeech coding,image analysisand image coding[1 ,2 ] .When applied to the low-rate subband image coding,the symmetricextension method[3] has been shown to outperform the circular convolution method andyield both objective and subjective quality improvementat image boundaries.The symmet-ric extension method requires linear-phase scaling filters and wavelet filters.Two-bandbiorthogonal symmetric waveletbases have been const… 相似文献
105.
The distinctive characteristics of the modern Pearl River delta formation and development are divided phases, diversity and imbalance in spatial and temporal. The delta was moving seaward gradually in a long period after the last Holocene glacial stage and the ancient drowned Pearl River estuary was predominated by tide. The delta was expanding quickly since fluvial force was turned to be leading status about 2500 years ago. The sediment grain size was changing longitudinally from coarser to finer. As well as the finer sediment may be reworked and redistributed shoreward by tidal current nearby the river mouth. And the fluvial-dominated delta is developed by the mutual deposition reflected in the vertical direction. According to the spatial difference of land-ocean interaction, the main body of the Pearl River delta which is the fluvial-dominated and protruding seaward is coupled with or concomitant with the estuaries and tide-dominated deltas which are adjoined to both sides of the main part like two wi 相似文献
106.
In this paper, the problem of when the sub-direct sum of two strictly diagonally dominant P-matrices is a strictly diagonally dominant P-matrix is studied. In particular, it is shown that the subdirect sum of overlapping principal submatrices of strictly diagonally dominant P-matrices is a strictly diagonally dominant P-matrix. It is also established that the 2-subdirect sum of two totally nonnegative matrices is a totally nonnegative matrix under some conditions. It is obtained that a partial totally nonnegative matrix, whose graph of the specified entries is a monotonically labeled 2-chordal graph, has a totally nonnegative completion. Finally, a positive answer to the question (IV) in Fallat and Johnson [Shaun M. Fallat, C.R. Johnson, J.R. Torregrosa, A.M. Urbano, P-matrix completions under weak symmetry assumptions, Linear Algebra Appl. 312 (2000) 73-91] is given for P0-matrices. 相似文献
107.
Zong Xiju~ Zhao Yi~ Yin Zhaoyang~ Chi Tao~ Dept.of Math. Zhongshan Univ. Guangzhou China. First Middle School of Tengzhou Shandong China. School of Control Science Engineering Jinan Univ. Jinan China 《高校应用数学学报(英文版)》2007,(3)
In this paper,the boundary control problem of a distributed parameter system described by the Schrdinger equation posed on finite intervalα≤x≤β: iyt yxx |y|~2y=0, y(α,t)=h_`1(t),y(β,t)=h_2(t)for t>0(S) is considered.It is shown that by choosing appropriate control inputs(h_j),(j=1,2)one can always guide the system(S)from a given initial stateφ∈H~s(α,β),(s∈R)to a terminal stateΨ∈H~s(α,β),in the time period[0,T].The exact boundary controllability is obtained by considering a related initial value control problem of Schrdinger equation posed on the whole line R.The discovered smoothing properties of Schrdinger equation have played important roles in our approach;this may be the first step to prove the results on boundary controllability of(semi-linear)nonlinear Schrdinger equation. 相似文献
108.
Shun Fu ZHOU Jing Yu SU Long Mei ZENG* School of Chemistry Engineering Zhongshan University Guangzhou 《中国化学快报》2001,(12)
The 1, 3-dipolar cycloaddition reaction between 3-hydroxypyridiniun betaines and a great variety of dipolarphiles, such as CH2=CH-CN, CH2=CH-COCH3, CH2=CH-COOCH3, CH2=CH(CH3)-COOCH3 were first investigated by Alan R. Katritzky et al.1-3. Generally, the olefinic dipolarphiles containing a strongly electron-withdrawing group are more active. Vinyl acetate 2 is an electron-rich dipolarphile, it is very difficult to carry out 1, 3-dipolar cycloaddition reaction with 3-hydropyridin… 相似文献
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