Synthesis, characterization and catalytic performances of S2O8 2−/Al-x wt%Ce–Zn–O solid acid catalysts

Abstract

New types of S 2 O 8 2-/Al-x wt%Ce-Zn-O solid acid catalysts were prepared by the sol-gel method. Their catalytic performances for the synthesis of n-butyl acetate from acetic acid and n-butanol were investigated. The characterization of prepared catalysts was performed using XRD, IR, TG-DSC and SEM. The experimental results showed that the S 2 O 8 2-/Al-2.5 wt%Ce-Zn-O solid acid catalyst exhibited an optimal esterification performance with 98.71% esterification efficiency under the optimum synthesis conditions. Moreover, the S 2 O 8 2-/Al-2.5 wt%Ce-Zn-O solid acid catalyst retained its high activity with above 95% esterification efficiency after being used repeatedly for seven times, which indicated that the S 2 O 8 2-/Al-2.5 wt%Ce-Zn-O solid acid catalyst had excellent stability.

Exploiting the therapeutic potential of microRNAs in human cancer

“…In contrast, overexpression of miR-342 significantly inhibits tumor growth and lung metastasis in nude mice. This newly identified miR-342--DNMT1 link provides a potential therapeutic target for the treatment of CRC [10].…”

“…Silencing of miR-181 leads to a reduction in the motility and invasion of hepatocellular CSCs [5] miR-193a Increase in p53-deficient tumors p53 Chemotherapy causes p63/p73-dependent induction of miR-193a-5p, thereby limiting chemosensitivity due to miRNA-mediated feedback inhibition of p73 [4] miR-199a/b Decrease in HCC PAK4 Suppresses HCC growth through inhibiting PAK4/ Raf/MEK/ERK pathway both in vitro and in vivo [15] miR-200a Decrease in pancreatic cancer DCAMKL-1 siRNA-mediated knockdown of DCAMKL-1 in cancer cells induces miR-200a along with downregulation of EMT-associated transcription factors ZEB1, ZEB2, Snail, Slug and Twist [23] miR-340 Decrease in aggressive breast cancer c-Met Suppresses tumor cell migration and invasion through the regulation of MMP-2 and MMP-9 expression [19] miR-342 Decrease in CRC DNMT1 Dramatically reduces DNMT1 expression, which in turn reactivates ADAM23, Hint1, RASSF1A and RECK genes via promoter demethylation [10] miR-488* Decrease in PCa AR Downregulates the transcriptional activity of AR and inhibits the endogenous AR protein production [16] miR-499 Increase in highly invasive CRC FOXO4, PDCD4 Promotes CRC cell migration and invasion in vitro as well as lung and liver metastasis in vivo [18] miR-516a Decrease in highly metastatic GC Sulfatase 1 Atelocollagen-mediated delivery of a miR-516a-3p expression vector into orthotopic highly metastatic tumors may have a therapeutic application in blocking metastatic dissemination of GCs [22] miR-520b HBXIP [20] AR Thus miR-193a inhibition may provide a new therapeutic opportunity in p53-deficient tumors [4]. Cancer stem cells (CSCs) hold the extensive proliferative and self-renewal potential necessary to develop cancer.…”

A novel solid acid catalyst synthesized from ZnAl2O4 spinel and its application in the esterification of acetic acid and n-butyl alcohol

“…6-9 A nanosized sulfated ZnFe 2 O 4 catalyst with highly ordered mesoporous was found to be highly active towards commercially important ne chemicals. [12][13][14] Therefore, the ZnAl 2 O 4 spinel may be a promising carrier for solid acid. 11 Nevertheless, the literature on the catalytic applications of S 2 O 8 2À / ZnAl 2 O 4 catalyst is scanty.…”