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941.
942.
Bin Yu 《Journal of Physics and Chemistry of Solids》2010,71(4):468-116
Casein, a natural biopolymer contained in milk, has been successfully intercalated into a Ca-Al-LDH host structure. Synthesis was performed by rehydration of tricalcium aluminate in the presence of casein. The resulting nanohybrids were characterized by powder X-ray diffraction (XRD), elemental analysis, infrared spectroscopy (IR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Further experiments revealed that the single protein strains intercalate instead of the entire casein sub micelles, which are present in milk. Additionally, the pure phospho protein fractions α- and β-casein, which make up ∼80 wt% of total casein were isolated and intercalated into the Ca-Al-LDH host structure, yielding a biopolymer-inorganic hybrid material. 相似文献
943.
The potential of using encapsulation by MEA, DEA and TEA to control the morphology of ZnO powders was investigated. The crystallite and particle size decreased as a function of aminoalcohol concentration. We found that aminoalcohols can inhibit the crystal growth of ZnO along the c-axis. A steric effect by TEA more strongly influenced the formation of different ZnO shapes than did MEA and DEA. The value of the band gap was dependent on the crystallite size, particle size and particle shape. 相似文献
944.
945.
946.
Summary. We derive error bounds for bivariate spline interpolants which are calculated by minimizing certain natural energy norms.
Received March 28, 2000 / Revised version received June 23, 2000 / Published online March 8, 2002
RID="*"
ID="*" Supported by the National Science Foundation under grant DMS-9870187
RID="**"
ID="**" Supported by the National Science Foundation under grant DMS-9803340 and by the Army Research Office under grant DAAD-19-99-1-0160 相似文献
947.
Gaven J. Martin 《Mathematische Annalen》2002,324(2):329-340
A uniformly quasiregular mapping, is a mapping of the m-sphere with the property that it and all its iterates have uniformly bounded distortion. Such maps are rational with respect to
some bounded measurable conformal structure and there is a Fatou-Julia type theory associated with the dynamical system obtained
by iterating these mappings. We begin by investigating the analogue of Siegel's theorem on the local conjuga cy of rotational
dynamics. We are led to consider the analytic continuation properties of solutions to the highly nonlinear first order Beltrami
systems. We reduce these problems to a central and well known conjecture in the theory of transformation groups; namely the
Hilbert-Smith conjecture, which roughly asserts that effective transformation groups of manifolds are Lie groups. Our affirmative
solution to this problem then implies unique analytic continuation and Siegel's theorem.
Received: 14 September 2000 / Revised version: 23 November 2001 / Published online: 5 September 2002
RID="*"
ID="*" Research supported in part by grants from the Marsden Fund and Royal Society (NZ). 相似文献
948.
Small compact perturbation of strongly irreducible operators 总被引:4,自引:0,他引:4
An operatorT onH is called strongly irreducible ifT is not similar to any reducible operators. In this paper, we shall say yes to answer the following question raised by D. A. Herrero.Given an operatorT with connected spectrum (T) and a positive number , can we find a compact operatorK with K < such thatT+K is strongly irreducible?Supported by National Natural Science Foundation of China(19901011), Mathematical Center of State Education Commission of China and 973 Project of China 相似文献
949.
In this paper, we obtain the general permutation formulas and composition formulas of singular integral of the Bochner-Martinelli type on a closed piecewiseC
(1) smooth manifold. As an application, we consider the corresponding singular integral equation of linear variable coefficients, and prove that the singular integral equation can be transformed to an equivalent Fredholm equation, whose characteristic equation has a unique solution in
, here
denotes the function set which satisfies the Hölder condition on D and holomorphically expands to domainD.Corresponding author. Project supported in part by the Mathematical Tian Yuan Foundation of China (Grant No. TY10126033). 相似文献
950.
Cornelis V. M. van der Mee André C. M. Ran Leiba Rodman 《Integral Equations and Operator Theory》2002,44(1):50-70
Polar decompositions with respect to an indefinite inner product are studied for bounded linear operators acting on a
space. Criteria are given for existence of various forms of the polar decompositions, under the conditions that the range of a given operatorX is closed and that zero is not an irregular critical point of the selfadjoint operatorX
[*]X. Both real and complex spaces
are considered. Relevant classes of operators having a selfadjoint (in the sense of the indefinite inner product) square root, or a selfadjoint logarithm, are characterized.The work of this author was partially supported by INdAM-GNCS and MURSTThe work of this author was partially supported by NSF grant DMS-9988579. 相似文献