Stereoelectronic effects on metallation of 1,3-dioxanes

Metallation of the acetal (H-2) proton in 1,3-dioxolanes, 1,3-dioxanes and open chain acetals is possible only if the proton can occupy an “equatorial-like” conformation.     

Highly efficient drug delivery with gold nanoparticle vectors for in vivo photodynamic therapy of cancer

A highly efficient drug vector for photodynamic therapy (PDT) drug delivery was developed by synthesizing PEGylated gold nanoparticle conjugates, which act as a water-soluble and biocompatible "cage" that allows delivery of a hydrophobic drug to its site of PDT action. The dynamics of drug release in vitro in a two-phase solution system and in vivo in cancer-bearing mice indicates that the process of drug delivery is highly efficient, and passive targeting prefers the tumor site. With the Au NP-Pc 4 conjugates, the drug delivery time required for PDT has been greatly reduced to less than 2 h, compared to 2 days for the free drug.     

Synthesis and Characterization of Homopolymers and Copolymers Containing closo‐[B12H12]2− Boron Cage Derivatives

Chains of cages : Neutral/ionic [B₁₂H₁₂]^2? boron‐cage‐functionalized methacrylate and styrene homopolymers or copolymers (see picture) are non‐crystalline solids, T_g increases as the number of B₁₂ cages in the chain of polystyrene increases, and homopolymers retain more weight than the copolymers when heated to 400 °C.

     

Large Strain Response of Kinematic Hardening Elastoplasticity with the Logarithmic Rate: Swift Effect in Torsion

Recently, a new Eulerian rate type kinematic hardening elastoplasticity model has been established by utilizing the newly discovered logarithmic rate. It has been proved that this model is unique among all the objective kinematic hardening elastoplastic models with all possible objective corotational stress rates and other known objective stress rates by virtue of the self-consistency criterion: the hypoelastic formulation intended for elastic behaviour must be exactly integrable to deliver a hyperelastic relation. The finite simple shear response of this model has been studied and shown to be reasonable for both shear and normal stress components. The objective of this work is to further study the large deformation response of this model, in particular the well-known Swift effect, in torsion of thin-walled cylindrical tubes with free ends. Analytical perturbation solution and numerical solution are presented for the case of linear kinematic hardening at large compressible deformation. It is shown that the prediction from the foregoing model is in good accord with experimental data reported in literature.