Biomedical subjects

Tao Tu

Publications and source records attributed to Tao Tu.

5 recordsLinked to original sources

PubMed2003

Highly regio- and enantioselective Heck reaction of N-methoxycarbonyl-2-pyrroline with planar chiral diphosphine-oxazoline ferrocenyl ligands.

[reaction: see text] A series of planar chiral diphosphine-oxazoline ferrocene ligands were effectively applied in the asymmetric arylation of N-methoxycarbonyl-2-pyrroline, and up to 99% ee was observed for the product 3. The regioselectivity of this reaction was strongly affected by the different precursors of the palladium species and the polarity of the solvent.

Ferrous Compounds↗

PubMed2003

Asymmetric catalysis with chiral ferrocene ligands.

Chiral ferrocene ligands have been widely used in asymmetric catalysis. The advantages of using ferrocene as a scaffold for chiral ligands are described, particularly those regarding planar chirality, rigid bulkiness, and ease of derivatization. The role of planar chirality in 1,2- and 1,1'-disubstituted ferrocene systems is discussed. By using a bulky ferrocene fragment, novel ferrocene ligands were designed, and high enantioselectivity and regioselectivity were achieved in the allylic substitution reaction of monosubstituted allyl substrates. Using the tunable electronic properties of a diphosphine-oxazoline ferrocenyl ligand, the regioselectivity of the intermolecular asymmetric Heck reaction was also examined.

Journal Article↗

PubMed2002

Renormalization group theory for perturbed evolution equations.

We show that proto-RG (renormaliation group) theory can be used to give a systematic description of the evolution of soltion of perturbed equations. The equations describing the deformation of its shape as the effect of perturbation are proto-RG equations. The RG approach may be simpler than inverse scattering theory (IST) and another approaches, because it dose not rely on any knowledge of IST. It is very concise and easy to understand.

Journal Article↗

PubMed2002

Iterative renormalization group for anomalous dimension in a nonlinear diffusion process.

We construct a classical successive method, the Picard method in integral equation theory, to make an iterative algorithm with the renormalization group (RG) approach to calculate the anomalous dimension in a nonlinear diffusion equation. We find our result improves than the original RG work because we begin with the var epsilonth RG solution, not the trivial fixed-point solution.

Journal Article↗

PubMed2002

Analysis on performance and optimization of frequency-domain near-infrared instruments.

Frequency-domain near-infrared techniques have been widely used to detect the optical properties of biological tissues noninvasively. In this paper we propose an analytical model to evaluate the performance of frequency-domain instruments. Based on the diffusion equation and the transfer properties of optoelectronic components, we treat all parts, including the medium, as two-port networks and apply systematic methods to answer questions concerning frequency-domain instruments. Experiments show that this method can reasonably reflect the properties of the instrument within an accuracy of 7%. This kind of method can be used to design suitable instruments for various applications. We also analyze the selection of the instrument parameters to achieve optimal performance at an efficient cost using this analytical model.

Fiber Optic Technology↗