Naphtha Reforming Over Zeolite-Hybrid-Type Catalysts

Author(s):  
R. L. Freed ◽  
M. J. Kelley

The commercial introduction of Pt-Re supported catalysts to replace Pt alone on Al2O3 has brought improvements to naphtha reforming. The bimetallic catalyst can be operated continuously under conditions which lead to deactivation of the single metal catalyst by coke formation. Much disagreement still exists as to the exact nature of the bimetallic catalyst at a microscopic level and how it functions in the process so successfully. The overall purpose of this study was to develop the materials characterization tools necessary to study supported catalysts. Specifically with the Pt-Re:Al2O3 catalyst, we sought to elucidate the elemental distribution on the catalyst.


2021 ◽  
Vol 60 (4) ◽  
pp. 2122-2126
Author(s):  
Marta A. Fik-Jaskółka ◽  
Izabela Pospieszna-Markiewicz ◽  
Giovanni N. Roviello ◽  
Maciej Kubicki ◽  
Wanda Radecka-Paryzek ◽  
...  

Information ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 10
Author(s):  
Stavroula Tzima ◽  
Georgios Styliaras ◽  
Athanasios Bassounas

Escape Rooms are presently considered a very popular social entertainment activity, with increasing popularity in education field, since they are considered capable of stimulating the interest of players/students and enhancing learning. The combined game mechanics have led to blended forms of Escape Rooms, the Serious Escape Games (SEGs) and the hybrid type of Escape Rooms that uses Augmented Reality (AR)/Virtual Reality technology, a type that is expected to be widely used in the future. In the current study, the MillSecret is presented, a multi-player Serious Escape Game about local cultural heritage, where the players must solve a riddle about the cultural asset of watermills. MillSecret uses AR technology and it was designed to be conducted in the real-physical environment and in an informal educational context. The paper describes the game, its implementation, the playing process, and its evaluation, which aimed to study the feasibility of game conduction in outdoor settings and the views and experience of players with the game, the local cultural heritage and local history. Evaluation results reveal, among other findings, a very positive first feedback from players that allows us to further evolve the development of the game.


Epigenomes ◽  
2021 ◽  
Vol 5 (1) ◽  
pp. 5 ◽  
Author(s):  
Ryohei Wada ◽  
Wataru Yoshida

N6-methyladenine modification (m6dA) has recently been identified in eukaryote genomic DNA. The methylation destabilizes the duplex structure when the adenine forms a Watson–Crick base pair, whereas the methylation on a terminal unpaired adenine stabilizes the duplex structure by increasing the stacking interaction. In this study, the effects of m6dA modification on the thermal stability of four distinct telomeric G-quadruplex (G4) structures were investigated. The m6dA-modified telomeric oligonucleotide d[AGGG(TTAGGG)3] that forms a basket-type G4 in Na+, d[(TTAGGG)4TT] that forms a hybrid-type G4 in K+ (Form-2), d[AAAGGG(TTAGGG)3AA] that forms a hybrid-type G4 in K+ (Form-1), and d[GGG(TTAGGG)3T] that forms a basket-type G4 with two G-tetrads in K+ (Form-3) were analyzed. Circular dichroism melting analysis demonstrated that (1) A7- and A19-methylation destabilized the basket-type G4 structure that formed in Na+, whereas A13-methylation stabilized the structure; (2) A15-methylation stabilized the Form-2 G4 structure; (3) A15- and A21-methylations stabilized the Form-1 G4 structure; and (4) A12-methylation stabilized the Form-3 G4 structure. These results suggest that m6dA modifications may affect the thermal stability of human telomeric G4 structures in regulating the biological functions.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 888
Author(s):  
Hiro Uemachi ◽  
Yuuya Kasahara ◽  
Keisuke Tanaka ◽  
Takumi Okuda ◽  
Yoshihiro Yoneda ◽  
...  

Nucleic acid aptamers have attracted considerable attention as next-generation pharmaceutical agents and delivery vehicles for small molecule drugs and therapeutic oligonucleotides. Chemical modification is an effective approach for improving the functionality of aptamers. However, the process of selecting appropriately modified aptamers is laborious because of many possible modification patterns. Here, we describe a hybrid-type systematic evolution of ligands by exponential enrichment (SELEX) approach for the generation of the artificial nucleic acid aptamers effective against human TROP2, a cell surface protein identified by drug discovery as a promising target for cancer therapy. Capillary electrophoresis SELEX was used for the pre-screening of multiple modified nucleic acid libraries and enrichment of TROP2 binding aptamers in the first step, followed by functional screening using cell-SELEX in the second step for the generation of cell-internalizing aptamers. One representative aptamer, Tac-B1, had a nanomolar-level affinity to human TROP2 and exhibited elevated capacity for internalization by cells. Because of the growing interest in the application of aptamers for drug delivery, our hybrid selection approach has great potential for the generation of functional artificial nucleic acid aptamers with ideal modification patterns in vitro.


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