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1.
周治修 《浙江大学学报(理学版)》2004,31(6):610-613
ZULLI L首先构造了一个用于计算纽结Kauffman尖括号多项式的模2矩阵,纽结的trip矩阵.为了构造链环的trip矩阵,引入了一个带标识的穿有m个孔的圆盘来取代纽结情形下的圆盘,其中m为链环的分支数.主要结果为:定理若状态S是从状态AA…A经过i1,i2,…,ip位置上的标记替换(A换成B)而得的状态.设Ts是将trip矩阵T的左上角的n×n子块中ai1i1,ai2i2,…,aipip之值进行替换(0→1或1→0)所得的矩阵,则#(L|S)=n+m-秩(Ts).因此计算链环Kauffman尖括号多项式就归结为计算一组模2矩阵的秩. 相似文献
2.
We study the cone-manifolds whose singular sets are obtained by orbifold and spontaneous surgeries on components of the Borromean rings. We establish existence of geometric structures on these manifolds. For manifolds with hyperbolic structure we obtain an integral representation for volumes. 相似文献
3.
提出级联佛克脱型原子滤光器(Linked VADOF)的新构想。从理论上分析并计算了级联佛克脱型原子滤光器的透射谱。结果表明,级联佛克脱型原子滤光器将佛克脱型原子滤光器的多峰改造为单峰结构,具有比佛克脱型原子滤光器更窄的线宽和更高的噪声抑制比。将这种新型结构应用于激光信标锁频。该锁频方案提高了信标光频率的稳定性。在此基础上,给出了发射端采用级联佛克脱型原子滤光器锁频,接收端采用法拉第型原子滤光器(FADOF)滤光的新型卫星激光链路系统。外场初步联调实验表明了该系统的可行性。 相似文献
4.
AnEstimateofInequalityofSignatureandNullityforLinks¥LiQisheng(李起升)(Dept.OfMath.HenanUniversity,Kaifeng475001)Abstract:Aninequ... 相似文献
5.
ZHANG Qi-Wei WANG Gui-Xian 《结构化学》2007,26(5):551-554
The title compound, [Cu(dpa)(2,2'-bipy)(H2O)2]n 1 (H2dpa = diphenic acid and 2,2'- bipy = 2,2'-bipyridine), has been synthesized and its structure was determined by single-crystal X-ray diffraction. The crystal is of orthorhombic, space group P212121 with a = 10.597(4), b = 11.317(4), c = 17.630(7) , V = 2114.3(14) 3, C24H20CuN2O6, Mr = 495.97, Z = 4, Dc = 1.558 g/cm3, μ = 1.079 mm-1, F(000) = 1020, Flack value = 0.052(18), R = 0.0430 and wR = 0.1016 for 3381 observed reflections (I > 2σ(I)). In compound 1, the dpa ligands link metal ions into helical structures in the same direction. 相似文献
6.
Simulation of aerated lagoon using artificial neural networks and multivariate regression techniques
Karla Patricia Oliveira-Esquerre Aline C. da Costa Roy Edward Bruns Milton Mori 《Applied biochemistry and biotechnology》2003,106(1-3):437-449
The aim of this study was to develop an empirical model that provides accurate predictions of the biochemical oxygen demand
of the output stream from the aerated lagoon at International Paper of Brazil, one of the major pulp and paper plants in Brazil.
Predictive models were calculated from functional link neural networks (FLNNs), multiple linear regression, principal components
regression, and partial least-squares regression (PLSR). Improvement in FLNN modeling capability was observed when the data
were preprocessed using the PLSR technique. PLSR also proved to be a powerful linear regression technique for this problem,
which presents operational data limitations. 相似文献
7.
A systematic quantum chemical characterization of intrinsic structure, energies and spectral properties of all the studied cross-link adducts formed by the novel trans platinum with thiazole ligand has been carried out at B3LYP/6-31G^* level of theory with the Lanl2dz pseudo potential basis set for the Pt atom. Special attention has been paid to the relative stability of these complexes and the factors that probably alter the order of the relative stability. The important influence of hydrogen bond on the structures, the energies and the spectral property was revealed. Other factors that contribute to relative stability including solvation effect, entropy and electronic delocalization energy were taken into account. The stability energy of the whole complex, and the interaction energy between two purine bases and the [Pt-(NH3)thiazole]^2+ group were adopted to study the interplay among subsystems and their contribution to relative stability of all the studied cross-link model. Finally, basic spectral properties of these complexes including H(8) chemical shifts of all the studied complexes and the VCD (vibrational circular dichroism) spectra of two pairs of GG chelate enantiomers, were provided in order to define the structure of the most possible duplex bearing novel trans platinum drug lesions. 相似文献
8.
E. J. Janse van Rensburg E. Orlandini D. W. Sumners M. C. Tesi S. G. Whittington 《Journal of statistical physics》1996,85(1-2):103-130
We consider a discrete ribbon model for double-stranded polymers where the ribbon is constrained to lie in a three-dimensional lattice. The ribbon can be open or closed, and closed ribbons can be orientable or nonorientable. We prove some results about the asymptotic behavior of the numbers of ribbons withn plaquettes, and a theorem about the frequency of occurrence of certain patterns in these ribbons. We use this to derive results about the frequency of knots in closed ribbons, the linking of the boundary curves of orientable closed ribbons, and the twist and writhe of ribbons. We show that the centerline and boundary of a closed ribbon are both almost surely knotted in the infinite-n limit. For an orientable ribbon, the expectation of the absolute value of the linking number of the two boundary curves increases at least as fast as n, and similar results hold for the twist and writhe. 相似文献
9.
The mononuclear vanadium(Ⅴ) complex with 2-hydroxyl-1-naphthaldehyde isoncotinoyl hydrazone was synthesized and characterized by single-crystal X-ray diffraction.The crystal is of monoclinic,space group P2 1/n with a = 10.3153(15),b = 7.4024(11 ),c = 24.413(4) (A),β= 101.911(2)°,V= 1824.0(5) (A)3,Z = 4,Mr = 427.28,Dc = 1.556 g/cm3,F(000) = 880,μ(MoKα) =0.591,the final R = 0.0372 and wR = 0.0926.The vanadium(Ⅴ) atom adopts a distorted square-pyramidal geometry coordinated by the tridentate ligand and two oxygen atoms.The hydrogen bonds and strong π…π stacking interactions link the complex molecules into a 3-D network structure. 相似文献
10.
WANG Jian-Guo XIAO Yong-Jun Li Zheng-Ming SONG Hai-Bin 《结构化学》2007,26(5):501-504
The crystal structure of the title compound (C17H16N4O3S2, Mr = 388.46) has been determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/c with a = 13.688(2), b = 16.704(3), c = 8.3308(12) , β = 99.474(6)o, V = 1878.8(5) 3, Mr = 388.46, Z = 4, Dc = 1.373 g/cm3, μ = 0.308 mm–1, F(000) = 808, R = 0.0389 and wR = 0.0917. X-ray analysis reveals that the crystal structure involves intermolecular N–H…O and N–H…N hydrogen bonds, which link the molecules into a layer parallel to the ac plane. 相似文献