A series of isostructural UiO-66-X (X = H, NH, Br, (OH), (SH)) catalysts have been successfully synthesized by modifying different functional groups on the ligand. The effects of the ligand modification of UiO-66 were investigated for their photocatalytic activity of Rhodamine B degradation under visible light. Surprisingly, UiO-66-NH and UiO-66-(OH) which have narrow bandgaps and excellent visible light absorption do not show outstanding photocatalytic performances compared to UiO-66 and UiO-66-Br. Electrochemical test results indicated that the conduction band potential of UiO-66-X and the separation efficiency of electrons were quite important in these photocatalytic reactions, other than the electronic effect as reported. Similar photocatalytic degradation behaviors were found for Congo red and methyl orange. Herein, we firstly reported different mechanisms of selective degradation in the case of UiO-66, which subverted the previous understanding of photodegradation behavior.

No abstract

No abstract

Objective. To probe into the early diagnosis value of transfer coefficient ( K trans ) and rate constant ( K ep ) of the dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) hemodynamic parameters in patients with hepatocellular carcinoma (HCC). Methods. Fifty patients with HCC diagnosed in our hospital from May 2017 to May 2020 were studied retrospectively as the patient group (PG), and 45 cases with benign liver nodules diagnosed in our hospital during the same period were collected as the control group (CG). K trans , K ep , and AFP levels were compared between PG and CG. The diagnostic value of K trans and K ep in HCC were observed, and their correlations with patient clinical data were analyzed. The diagnostic value of K trans and K ep combined with AFP in clinical staging, differentiation degree, and distant metastasis was compared. Results. K trans , K ep , and AFP were notably higher in cases than in controls ( P < 0.05 ), indicating their high diagnostic value in HCC. K trans and K ep present elevated expression in HCC patients with clinical stage III-IV, low differentiation, and distant metastasis ( P < 0.05 ). Furthermore, it is found that the combined detection with either K trans or K ep can improve the clinical diagnostic value of AFP in the clinical stage and differentiation of HCC. However, the combined diagnosis showed little effect in raising the sensitivity of AFP in distant metastasis. Conclusion. DCE-MRI hemodynamic parameters K trans and K ep have high clinical value in early diagnosis and differentiation of HCC patients.