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101.
We reformulate various versions of infinitely divisible cascades proposed in the literature using stochastic equations. This approach sheds a new light on the differences and common points of several formulations that have been recently provided by several teams. In particular, we focus on the simplification occurring when the infinitely divisible noise at the heart of such model is stable: an independently scattered random measure becomes a stable stochastic integral. In the last section we discuss the D-dimensional generalization.  相似文献   
102.
Catalyzed by ytterbium(III) triflate hydrate [Yb(OTf)3.xH20], the Michael addition and cyclocondensation of α,β-unsaturated ketones with active methylene compounds to afford the 1,4-adducts and benzo[b]pyran derivatives, respectively were studied.  相似文献   
103.
Over the last couple of years molecular imaging has been rapidly developed to study physiological and pathological processes in vivo at the cellular and molecular levels. Among molecular imaging modalities, optical imaging stands out for its unique advantages, especially performance and cost-effectiveness. Bioluminescence tomography (BLT) is an emerging optical imaging mode with promising biomedical advantages. In this survey paper, we explain the biomedical significance of BLT, summarize theoretical results on the analysis and numerical solution of a diffusion based BLT model, and comment on a few extensions for the study of BLT.  相似文献   
104.
For describing various complex nonlinear phenomena in the realistic world, the higher-dimensional nonlinear evolution equations appear more attractive in many fields of physical and engineering sciences. In this paper, by virtue of the Hirota bilinear method and Riemann theta functions, the periodic wave solutions for the (2+1)-dimensional Boussinesq equation and (3+1)-dimensional Kadomtsev Petviashvili (KP) equation are obtained. Furthermore, it is shown that the known soliton solutions for the two equations can be reduced from the periodic wave solutions.  相似文献   
105.
在CH3OH/H2O混合溶剂中,经2,4,6-三(2-吡啶基)-1,3,5-三嗪(tptz)、草酸和新制Ni(OH)2/NiCO3反应合成得到配合物[Ni(H2O)(tptz)(C2O4)]·4H2O.单晶X-射线衍射分析表明:它与已报道的[M(H2O)(tptz)(C2O4)]·4H2O(M=Co(2)、Cu(3)、Zn(4))配合物同晶形,属三斜晶系,P1空间群,晶胞参数a=7.760(2)A,b=12.116(2)A,c=13.031(3)A,α=78.76(4)°,β=83.84(3)°,γ=78.69(3)°,V=1175.3(5)A^3,Z=2,Dc=1.543,F(000)=562,R1=0.0472,wR2=0.1350,GOF=1.088.在配合物的结构基础上与同晶形结构进行比较分析,并研究了它们的IR及TG/DTA测试表征.  相似文献   
106.
Let μΩ^mb be the commutator generalized by μΩ, the n-dimensional Marcinkiewicz integral, and b ∈ BMO(R^n). The author establishes the weighted weak LlogL-type estimates for μΩ^mb when Ω satisfies a kind of Dini conditions, which improves the known result essentially.  相似文献   
107.
108.
朱森  苏丽  王立飞 《东北数学》2008,24(3):196-206
Abstract: We consider an approximation problem related to strongly irreducible operators, that is, does the direct sum of a strongly irreducible operator in B∞(Ω) and certain operator have a small compact perturbation which is a strongly irreducible operator in B∞(Ω)? In this paper, we prove that the direct sum of any strongly irreducible operator in B∞(Ω) and certain biquasitriangular operator have small compact perturbations which are strongly irreducible operators in B∞(Ω).  相似文献   
109.
Two Cd(Ⅱ) complexes, Cd2L2Cl2 (1) and Cd2L2(NCS)2 (2) (HL = N-(3-methoxylsalicylidene)-3-dimethylaminopropylamine) were synthesized and determined by EA, IR, TG and single-crystal X-ray diffraction. The crystallographic data are as follows: monoclinic, space group P21/n, a = 9.2710(9), b = 18.0069(18), c = 18.5562(19) A^°, β= 99.741(4)°, V = 3053.1(5), Z = 4,μ = 1.605, F(000) = 1536, R = 0.0264 and wR = 0.0699 for 1; orthorhombic, space group Pca21, a = 16.196(3), b = 11.506(2), c = 36.126(7) A^°, V = 6732(2), Z = 8,μ = 1.428, F(000) = 3264, R = 0.0376 and wR = 0.0877 for 2. There are two geometrically different octahedral Cd(Ⅱ) atoms, with N4O2 and O4Cl2 donor sets for 1 while N4O2 and N2O4 for 2. In the dinuclear Cd(Ⅱ) centers, the Cd(Ⅱ) atoms are held together by two deprotonted phenolate oxygen atoms from tetradentate L^- ligands. The thermal gravity data show two step decompositions with the residues of CdO for two complexes.  相似文献   
110.
利用球体随机旋转性好的特点,将包装样品的容器装入球内并放在样品旋转台中,在两台速度不同,方向垂直的步进电机带动下,球在旋转台上随机转动,实现对包装容器内的样品进行连续随机扫描,以达到减小由于包装容器的非均匀性对测量结果的影响,样品旋转装置由球面板、四根支柱,底座、步进电机及步进电机控制电路组成。采用两台型号为57BYG503的步进电机驱动球体旋转,步进电机控制器可对两台电机进行单独控制,并具有正反转功能,其转速分为2、5、8、12、16、20转/min六档,可连续长时间工作。  相似文献   
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