The recent discovery of superconductivity in iron arsenide compounds RFeAsO (R= rare earth) or AFe 2 As 2[1~8] (A= alkaline earth) attracts great attention due to the unexpected high T c in the system containing ferromagnetic elements like Fe. Similar to high T c cuprates, the superconductivity in iron arsenide is related to a layered structure. Searching for new superconductors with [FeAs] layer but of simpler structure will be of scientific significance either to build up new multilayered superconductors that may reach higher T c or to study the mysterious underlined superconducting mechanism in iron arsenide compounds. Here we report that a new superconducting iron arsenide system LiFeAs was found. The compound crystallizes into structure containing [FeAs] conducting layer that is interlaced with Li charge reservoir. Superconductivity was observed with T c up to 18 K in the compounds.

Carbon quantum dots (CQDs) are promising nanomaterials since they have smaller particle size, excellent biocompatibility, and low toxicity. However, no  one has found their high-scale inhibition performance so far. In this article, a new kind of green scale inhibitor, carboxyl carbon quantum dots (CCQDs), was synthesized through a simple method of thermal decomposition of citric acid. The as-prepared CCQDs have excellent scale inhibition performance for CaSO4 and BaSO4. With a static test of scale inhibition at a temperature of 0–80 °C, the antiscaling efficiency can reach 100% with low additions of CCQDs.

Mechanically robust, hollow carbon nanotube composite spheres that are permeable to large chemical species were prepared by a layer-by-layer assembly and templating technique.

An optofluidic laser based on a hollow-core negative-curvature fiber (HC-NCF) is proposed and demonstrated. The submicron-thick circular capillary tubes embedded in the cladding of the HC-NCF act as antiresonant elements and are used as both a resonator and dye microfluidic channels. A stable optofluidic dye laser with a low threshold of 15.14 nJ/mm2 is achieved. The laser is compact and robust and exhibits directional output.