The rhizosphere is colonized by a mass of microbes, including bacteria capable of promoting plant growth that carry out complex interactions. Here, by using a sterile experimental system, we demonstrate that Sphingomonas sp. Cra20 promotes the growth of Arabidopsis thaliana by driving developmental plasticity in the roots, thus stimulating the growth of lateral roots and root hairs. By investigating the growth dynamics of A. thaliana in soil with different water-content, we demonstrate that Cra20 increases the growth rate of plants, but does not change the time of reproductive transition under well-water condition. The results further show that the application of Cra20 changes the rhizosphere indigenous bacterial community, which may be due to the change in root structure. Our findings provide new insights into the complex mechanisms of plant and bacterial interactions. The ability to promote the growth of plants under water-deficit can contribute to the development of sustainable agriculture.

A series of composites of nanocrystalline TiO 2 with exposed {001} facets and high quality graphene sheets (GS) were synthesized via a one-step hydrothermal reaction in an ethanol-water solvent. The obtained {001} facets-exposed TiO 2 /GS photocatalysts were characterized by Raman spectroscopy (RS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction pattern (XRD), field emission scanning electron microscopy (SEM), transmission electron microscopy (TEM), ultraviolet visible (UV-vis) diffuse reflectance spectroscopy (DRS) and Electrical Impedance Spectroscopy (EIS). They showed a better photocatalyst properties than P25 and other normal TiO 2 /GS composites, which could be explained on the basis of the formation of chemical Ti-O-C bond and the formation of nano-sized Schottky interfaces at the contacts between TiO 2 and GS. The influence of the exposed {001} facets on the photocatalytic activity was investigated. The result showed that positively charged dye molecules are preferentially adsorbed onto the TiO 2 /GS composites due to the photogenerated charge gathered on GS. Overall, this work could provide new insights into the fabrication of TiO 2 -carbon composites as high performance photocatalysts and facilitate their application in addressing environmental protection issues.

We disclose in this study a Ni 6 AlO x catalyst prepared by coprecipitation for the reductive amination of biomass-derived aldehydes and ketones in aqueous ammonia under mild reaction conditions. The catalyst exhibited 99% yield toward 5-aminomethyl-2-furylmethanol in the reaction of 5-hydroxymethyl furfural with ammonia at 100 °C for 6 h under 1 bar H 2 . The catalyst was further extended to the reductive amination of a library of aromatic and aliphatic aldehydes and ketones with a yield in the range 81–90% at optimized reaction conditions. Besides, 5-hydroxymethylfurfural could react with a library of primary and secondary amines with yields in the range 76–88%. The catalyst could be easily recycled and reused without apparent loss of activity in four consecutive runs.

The selective N-monomethylation of amines is an important topic in fine chemical synthesis. Herein, for the first time, we described a selective N-monomethylation reaction of amines with paraformaldehyde and H in the presence of a CuAlO catalyst. A variety of amines, including primary aromatic amines, benzylamine and cyclohexylamine, as well as secondary amines, have been shown to be compatible with this reaction.