In-Depth Investigation of the Mechanism of Dehydration-Induced Phase Transformation from NbO(OH) to H-NbO: A Theoretical and Experimental Approach.

H-NbO is a promising energy material, which can be typically obtained from any other polymorph after conducting high temperature calcination (∼1273 K). Recently, a low-temperature dehydration from NbO(OH) was employed to prepare H-NbO at 723 K for 2 h, and yet the transformation mechanism has remained unclear in the literature. Here, the dehydration kinetic and phase transformation mechanism of the NbO(OH) were investigated for the first time by experiments, density functional theory, and molecular dynamics calculations.

The effects of Fe on sulfur-oxidizing bacteria (SOB) driven autotrophic denitrification.

With the short-term exposure to Fe, the mechanism of autotrophic denitrification and sulfide oxidation and the correlation between microbial community changes and environmental factors have been explored in the ADSOB process. RSM was used to optimize conditions for the maximum nitrate reduction and sulfide oxidation. About 88% of nitrate could be autotrophically denitrified to nitrogen by utilizing sulfide as the electron donor with the molar ratio C/N of 1.

In-situ synthesis of 3D GA on titanium wire as a binder- free electrode for electro-Fenton removing of EDTA-Ni.

Ethylenediaminetetraacetic acid (EDTA) could form stable complexes with toxic metals such as nickel due to its strong chelation. The three-dimensional (3D) macroporous graphene aerogels (GA), which was in-situ assembled by reduced graphene oxide (rGO) sheets on titanium wire as binder-free electrode, was presented as cathode for the degradation of EDTA-Ni in Electro-Fenton process. The X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscope (TEM) and Brunauer-Emmett-Teller (BET) results indicated 3D GA formed three dimensional architecture with large and homogenous macropore structure and surface area.

Treatment of Ni-EDTA containing wastewater by electrocoagulation using iron scraps packed-bed anode.

The unique electrocoagulator proposed in this study is highly efficient at removing Ni-EDTA, providing a potential remediation option for wastewater containing lower concentrations of Ni-EDTA (Ni ≤ 10 mg L). In the electrocoagulation (EC) system, cylindrical graphite was used as a cathode, and a packed-bed formed from iron scraps was used as an anode. The results showed that the removal of Ni-EDTA increased with the application of current and favoured acidic conditions.