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Rod-coil block copolymers (BCPs) can self-assemble into nanostructures that are useful for the fabrication of nanodevices. However, BCPs are generally difficult to self-assemble into highly ordered nanostructures due to their low chain mobility and strong rod-rod interaction. A facile approach is developed to achieve rapid self-assembly of rod-coil BCPs by blending them with selective additive and annealing in vacuum. Poly(diethyl hexyl oxy-p-phenylene vinylene)-b-poly(methyl methacrylate) (DEHPPV-b-PMMA or PVM) was used as a model copolymer to validate this approach. By adding 30 wt% of a rod-selective additive, p-phenylene vinylene (PV), into the PVM containing 67% (v/v) PMMA, the copolymer can easily self-assemble into lamellae structure at 150 °C for 1.5hr under 0.05 torr. This is a significant improvement over the 200 °C for 60 h for the sample without additive and vacuum annealing. This energy conservation process should have broad application in the fabrication of highly ordered nanostructure using BCPs.

To survive in a fiercely competitive business environment, it has become increasingly important for physical retailers to provide customers with services offering a better shopping experience. Many renovate and enlarge their shopping spaces to make their stores more enjoyable places to visit. The growth in social media and the use of mobile devices provide retailers with an opportunity to offer a context-aware guidance service to enhance customers' in-store shopping experience. In this research, by extracting and analysing shopping information (shopping context, visiting trajectory) and social information (user's interest, friends' influence), a contextual store shopping recommendation system is proposed to provide an appropriate route for first-time customers or those who are unfamiliar with a retailer's shopping space. Our experimental results show that the proposed model is effective in providing an appropriate shopping route and enhancing users' shopping experience, which could significantly improve the profitability and competitive advantage of the retailers. Mobile devices provides retailers with an opportunity to offer a context-aware guidance service for in-store shopping.We propose a contextual store shopping recommendation system for customers shopping path support.The proposed framework is developed based on extracting and analyzing shopping information and social information.The proposed model is effective in providing an appropriate shopping route and enhancing users shopping experience.

Scanning tunneling microscopy is utilized to investigate the local density of states of a CH3NH3PbI3–xClx perovskite in cross-sectional geometry. Two electronic phases, 10–20 nm in size, with different electronic properties inside the CH3NH3PbI3–xClx perovskite layer are observed by the dI/dV mapping and point spectra. A power law dependence of the dI/dV point spectra is revealed. In addition, the distinct electronic phases are found to have preferential orientations close to the normal direction of the film surface. Density functional theory calculations indicate that the observed electronic phases are associated with local deviation of I/Cl ratio, rather than different orientations of the electric dipole moments in the ferroelectric phases. By comparing the calculated results with experimental data we conclude that phase A (lower contrast in dI/dV mapping at −2.0 V bias) contains a lower I/Cl ratio than that in phase B (higher contrast in dI/dV).

The auhtors report 3D biomimetic scaffolds using polymer blend of polyurethane and cellulose for cardiac tissue engineering. The biocompatible and biodegradable polyurethane is designed, synthesized and characterized. By incorporating 10 wt% of naturally ordered cellulose into the polyurethane and electrospinning them into 3D scaffold, the scaffold exhibits good biocompatibility and mechanical property to support and accommodate constant cycles of contraction/expansion of cardiac tissue. The biocompatibility is further improved using scaffold fabricated from aligned fibers due to synergistic effects between cells and ordered macromolecules. The anisotropic structured scaffold is mimicked the extracellular matrix and has therapeutic potential in reconstruction of damaged myocardium.

A facile approach is reported to process rod-coil block copolymers (BCPs) into highly ordered nanostructures in a rapid, low-energy process. By introducing a selective plasticizer into the rod-coil BCPs during annealing, both the annealing temperature and time to achieve thermodynamic equilibrium and highly ordered structures can be decreased. This process improvement is attributed to enhanced chain mobility, reduced rod-rod interaction, and decreased rod-coil interaction from the additive. The novel method is based on kinetically facilitating thermodynamic equilibrium. The process requires no modification of polymer structure, indicating that a wide variety of desired polymer functionalities can be designed into BCPs for specific applications.

Scanning tunneling microscopy is utilized to investigate the local density of states of a CH