Amphiphilic liquid‐crystalline 4‐miktoarm star copolymers with a siloxane junction leading to cylindrically nanostructured templates for a siloxane‐based nanodot array

Well‐defined A₃B‐, A₂B₂‐, and AB₃‐type 4‐miktoarm star copolymers (M_n = 10,500–16,200, M_w/M_n = 1.16–1.18) consisting of poly(ethylene oxide) (PEO) and polymethacrylate bearing an azobenzene mesogen (PMA(Az)) as the arms and cyclotetrasiloxane as the core unit were synthesized using a combined route composed of a thiol‐ene click reaction and atom transfer radical polymerization. Microphase‐separated structures of the star copolymers in thin films with a thickness of approximately 100 nm were investigated by GISAXS and TEM. The A₃B‐type star‐(PEO)₃[PMA(Az)]₁ copolymer formed a more highly ordered PEO cylinder array with perpendicular alignment in the PMA(Az) matrix than that of the corresponding linear‐type block copolymer. The center‐to‐center distance of the PEO cylinders and the cylinder diameter were 13 and 4 nm, respectively. The highly ordered star‐(PEO)₃[PMA(Az)]₁ thin film was directly transferred to a siloxane‐based nanodot array by oxygen reactive ion etching. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1175–1188     

Study of optical response of spinel oxide by utilizing IR-THz spectromicroscopy

We performed a spectromicroscopic measurement on LiV₂O₄ in IR-THz (25 meV–1.5 eV) from 6–300 K under high pressures up to 20 GPa by using a DAC at the spectromicroscopy station (BL43IR) at SPring-8. At 40 K, a clear metal–insulator change was observed above 6 GPa in the optical conductivity spectra. The newly developed peak structure around 1 eV reflects the pseudo-gap forming under pressure at 40 K.     

Effects of entanglement on the scattering intensity of neutron compton scattering by a proton pair in solids

We calculate scattering functions S(q-->,omega) of neutron Compton scattering (NCS) for a proton (deuteron) pair in the entangled state caused by the indistinguishability of particles. From the calculation, it is concluded that the effect of entanglement on the scattering intensity is undetectable in NCS experiments because of their high energy transfer and broad energy resolution.     

Supramolecular nanocarrier of siRNA from PEG-based block catiomer carrying diamine side chain with distinctive pKa directed to enhance intracellular gene silencing

An siRNA nanocarrier formed through self-assembly of PEG-based block catiomer possessing two distinct amino groups with different pKa values in a side chain was developed. This design provided the carrier with a sufficient siRNA complexation and an assumed buffering capacity in the endosomes, allowing it to exhibit remarkable gene knockdown abilities as well as sufficient serum tolerability.     

Synthesis of conjugated oligomers having aromatic and enediyne units alternately in the backbone that show intense fluorescence emission

[structure: see text] Synthesis and fluorescence properties of pi-conjugated compounds having alternately an aromatic ring such as benzene, pyridine, and thiophene and an enediyne unit in the backbone are described.