Unveiling the Mechanism of Plasma-Catalytic Low-Temperature Water-Gas Shift Reaction over Cu/γ-AlO Catalysts.

The water-gas shift (WGS) reaction is a crucial process for hydrogen production. Unfortunately, achieving high reaction rates and yields for the WGS reaction at low temperatures remains a challenge due to kinetic limitations. Here, nonthermal plasma coupled to Cu/γ-AlO catalysts was employed to enable the WGS reaction at considerably lower temperatures (up to 140 °C).

Density Functional Theory Studies on the Hydrolysis of Levoglucosenone to 5-Hydroxymethylfurfural.

Selective conversion of lignocellulosic biomass-derived chemicals is of critical significance for sustainable fine and commodity chemical industries. Cellulose-derived levoglucosenone (LGO) has a promising potential for producing 5-hydroxymethylfurfural (HMF) with a substantial yield under acid conditions, but the mechanism is unidentified. Herein, we disclose the mechanism of LGO conversion to HMF in the aqueous phase without and with HSO as a catalyst by density functional theory (DFT) calculations for the first time.

Understanding the nature of NH-coordinated active sites and the complete reaction schemes for NH-SCR using Cu-SAPO-34 catalysts.

Cu-SAPO-34 zeolite catalysts show excellent NH3-SCR performance at low temperature, which is due to the catalytic capacity of copper species. Isolated CuII ions and CuIIOH are active sites, but their nature and role are not fully understood. This paper reports the DFT calculations in combination with ab initio thermodynamics to investigate NH3 and H2O coordination to copper species under typical NH3-SCR reaction conditions.

Irregular influence of alkali metals on Cu-SAPO-34 catalyst for selective catalytic reduction of NO with ammonia.

SCR activity of Cu-SAPO-34 catalyst was reduced by alkali metal ions. The alkali metals ions (Li, Na and K) have shown irregular influences on Cu-SAPO-34. The order of poisoning strengths under 400 °C was found to be: Na > K > Li, which is not consistent with the basicities of their corresponding metals.

Promoting effects of water on the NH-SCR reaction over Cu-SAPO-34 catalysts: transient and permanent influences on Cu species.

Cu-SAPO-34 catalysts with varied Cu loadings were synthesized through ion exchange to study the influence of water on the NH3-SCR reaction. The catalytic activities were evaluated by selective catalytic reduction of NO under a reactant feed in the presence/absence of water. Transient experiments were designed to study the response of NO conversion to the presence of water.

[Analysis and computational fluid dynamics simulation of hemodynamic influences caused by splenic vein thrombosis].

This paper aims to analyze the impact of splenic vein thrombosis (SVT) on the hemodynamic parameters in hepatic portal vein system. Based on computed tomography (CT) images of a patient with portal hypertension and commercial software MIMICS, the patient's portal venous system model was reconstructed. Color Doppler ultrasound method was used to measure the blood flow velocity in portal vein system and then the blood flow velocities were used as the inlet boundary conditions of simulation.

The co-effect of Sb and Nb on the SCR performance of the V2O5/TiO2 catalyst.

The effect of the Sb and Nb additives on the V(2)O(5)/TiO(2) catalyst for the selective catalytic reduction (SCR) of NO with NH(3) was investigated. The experimental results show that either Nb or Sb can improve the activity of V(2)O(5)/TiO(2) catalyst. Higher Nb loading led to higher N(2) selectivity.