Anaerobic Biotransformation of Nitro-Compounds to Amines by Bovine Rumen Fluid

Microorganims of the bovine rumen fluid biocatalyzed the reduction of nitro-compound substrates to yield the respective amines. This enzymatic process, using ruminal contents, has rarely been reported in associa- tion with the bioreduction of nitro groups. The biotransformation reactions catalyzed by this system were de- pendent of both the electronic characteristics and the area/volume of the nitro-substrates confirming the processes are enzymatic. The semi-preparative scale biotransformation went by in good yield showing the rumen fluid may be employed in the synthesis of amines under very mild conditions and, moreover, it may have application in the bioremediation of nitro-compounds.

Two-dimensional porous Cu-CuO nanosheets: Integration of heterojunction and morphology engineering to achieve high-effective and stable reduction of the aromatic nitro-compounds

The morphology and heterojunction engineering are effective ways to boost the performance of Cubased catalysts. Herein, we have reported the designed synthesis of two-dimensional Cu-Cu O heterojunction nanosheets(2D Cu-Cu O NS) based on 3-aminopropyl-triethoxysilane(APTES, KH550) aided synthetic strategy. The APTES can act as both the ligand and alkali(-OH) source to guide the large-scale synthesis of 2D Cu-based precursor, which can transform into 2D Cu-Cu O NS by the controllable post-treatment.The Si species from APTES can protect the particles from the severe aggregation and growth, guaranteeing the formation of 2D sheets composed of small-sized Cu-Cu O heterojunction(about 20 nm). The heterojunction interfaces can provide plentiful active sites to boost the catalytic ability. The 2D sheets can provide large accessible surface, being conducive to the contact of the catalyst and reactants. Benefiting from above virtues, the 2D Cu-Cu O NS showed the superior catalytic performance for the reduction of a series of nitro compounds, being superior to most reported non-noble metal-based catalysts. Notably,it exhibited good re-cycled performance with no obvious performance degradation after 10 consecutive catalysis. The present study will be promising to promote the application of the Cu-based catalysts, due to its ability to control the morphology and potential for the large-scale synthesis.

Fabrication of hierarchical MXene-based AuNPs-containing core-shell nanocomposites for high efficient catalysts

MXene is a new type of layered two-dimensional transition metal carbide materials differing from graphene, demonstrating intriguing chemical/physical properties. Here the chemical modification of MXene and next fabrication of core-shell MXene-COOH@(PEI/PAA)_n composites have been investigated. The obtained MXene-based composites were treated with gold nanoparticles to form MXene—COOH@(PEI/PAA)_n@AuNPs nanocomposites, and their catalytic properties for nitro-compounds were studied. The prepared nanocomposites demonstrated good catalytic activity and reproducibility, showing potential applications in composite catalysts and environmental fields.

Synthesis, characterization and fluorescence quenching of conjugated polymer containing triphenylamine group

Poly(triphenylamine-p-phenylenevinylene)s with two different end-groups were obtained through a Wittig polycondensation.The structures of two copoly-mers were characterized.Ultraviolet and visible spectro-scopy(UV-Vis)and photoluminescence(PL)spectra show the end-capped polymer emits intensive green light in both solution and film state.Their applications in the detection of nitro compounds were investigated,and the results show high fluorescence quenching sensitivity of the end-capped polymer towards o-nitrotoluene(o-NT).When the concentration of o-NT was 21.5×10^(-3) mol/L,the fluorescence quenching reached 96%.Additionally,after the exposure of polymer film in three different quenchers such as dinitrotoluene(DNT),p-nitrobenzo-quinone(p-BQ)and p-nitrotoluene(p-NT)for 600 s,its fluorescence quenching reached 93.6%,11.5%and 77.9%,respectively.This kind of polymer has great advantages in preparation and may find applications in the detection of nitro explosives.