Novel principle of seeded free electron lasers – Shanghai Institute of Applied Physics

Scientists at Shanghai Institute of Applied Physics (SINAP), Chinese Academy of Sciences demonstrated a novel principle of seeded free electron lasers, Echo-Enabled Harmonic Generation (EEHG) on Shanghai Deep UV Free Electron Laser (SDUV-FEL) facility. The result was published on Nature Photonics, Vol.6, No.6, 360-363, 2012.

The recent work done by the SINAP FEL team shows the first lasing of a free electron laser with the echo-enabled harmonic generation scheme, which is very promising for producing coherent laser at short wavelength down to the x-ray regime.

Source: CAS

Self-Healing Supramolecular Gels Developed at Zhejiang University

A research group at Zhejiang University headed by Prof. Huang Feihe recently developed a supramolecular gel with self-repair function, featuring large deformation and short recovery time. A relative paper was published in Angewandte Chemie International Edition.

Supramolecular gels are formed by colloidal particles tangling with non-covalent interactions. For the first time in the world, the research group headed by Prof. Huang developed two different kinds of supramolecular gels in simple process with excellent self-healing properties.

According to Dr. Zhang Mingming, the first author of the paper, the study used two different molecular cross-linking agents with pendent dibenzo[24]crown-8 units to develop two different kinds of supramolecular gels. Inside the gels there is a special axis-ring penetration structure which will be damaged with external stimulation. However, due to its stability, it will resume the penetration structure after a period of time. In experiments, these supramolecular gels will recover its elastic and viscous properties within one minute after being stretched to 100 times long. In 3 or 4 minutes, they will achieve complete self-repair.

Source: Zhejiang Univeristy News