scholarly journals Mechanical-Bond-Induced Exciplex Fluorescence in an Anthracene-Based Homo[2]catenane

2020 ◽  
Vol 142 (17) ◽  
pp. 7956-7967 ◽  
Author(s):  
Amine Garci ◽  
Yassine Beldjoudi ◽  
Mohamad S. Kodaimati ◽  
Jessica E. Hornick ◽  
Minh T. Nguyen ◽  
...  
Keyword(s):  
Mechanical Bond ◽  
Exciplex Fluorescence

Comparative Study of Acid Etching on Dental Enamel

2018 ◽  
Vol 69 (10) ◽  
pp. 2913-2915
Author(s):  
Daniela Jumanca ◽  
Anamaria Matichescu ◽  
Atena Galuscan ◽  
Laura Cristina Rusu ◽  
Cornelia Muntean
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Experimental Study ◽  
Orthophosphoric Acid ◽  
Dental Enamel ◽  
Acid Etching ◽  
Sealing Material ◽  
Mechanical Bond ◽  
Materials Used ◽  
Scanning Electron

This experimental study aims to analyse the effectiveness of various materials used in demineralisation of dental enamel. This work aims to create a mechanical bond by filling the pegs with sealing material. In order to achieve this goal, five teeth were compared using different concentrations of orthophosphoric acid and exposure times. In this regard, five different tests were performed and the results were analysed using the SEM technique (scanning electron microscopy). These comparative analyses revealed that etching using 35% orthophosphoric acid for one minute and etching using Icon Etch for two minutes were the most effective.

Study on Surfacing Technics of 18CrNiWA Engine Crankshaft Surfacing Welding with Flux-Cored Wire

2014 ◽  
Vol 926-930 ◽  
pp. 246-249 ◽  
Author(s):  
Yu Feng Zhang ◽  
Min Rui Li ◽  
Jian Cheng Wang
Keyword(s):  
Metal Powder ◽  
Ultrafine Particles ◽  
High Hardness ◽  
High Fracture Toughness ◽  
Strengthening Effect ◽  
High Fracture ◽  
Cored Wire ◽  
Mechanical Bond ◽  
Engine Crankshaft

It discussed repairing the worn engine crankshaft with chromium series metal powder-cored wire. The Mo, Mn, V, Ti metal powder and the SiC ultrafine particles, WC nanopowder added in chromium series metal powder-cored wire. That made the surfacing layer obtained high bonding strength, high hardness, and obtained high fracture toughness. The result indicated the SiC ultrafine particles/WC nanopowder could promotion the in-situ reaction in the surfacing layer, formed the dissemination strengthening, the melting strengthening and so on multi-mechanism strengthening effect. SiC and the metal matrix was not merely the mechanical bond, the partial regions were by the chemical bond. That realized in the structure continuity. And the repaired crankshaft surface wear-resisting disposition enhanced 24% than the original.

Symbiotic Control in Mechanical Bond Formation

2016 ◽  
Vol 55 (40) ◽  
pp. 12387-12392 ◽  
Author(s):  
Yuping Wang ◽  
Junling Sun ◽  
Zhichang Liu ◽  
Majed S. Nassar ◽  
Youssry Y. Botros ◽  
...  
Keyword(s):  
Bond Formation ◽  
Symbiotic Control ◽  
Mechanical Bond

Exciplex Fluorescence Visualization Systems for Pre-Combustion Diagnosis of an Automotive Gasoline Engine

1996 ◽  
Author(s):  
Jong U. Kim ◽  
Brage Golding ◽  
Harold J. Schock ◽  
Philip Keller ◽  
Daniel G. Nocera
Keyword(s):  
Gasoline Engine ◽  
Automotive Gasoline ◽  
Visualization Systems ◽  
Exciplex Fluorescence

scholarly journals Mechanically axially chiral catenanes and noncanonical mechanically axially chiral rotaxanes

2022 ◽  
Author(s):  
Stephen Goldup ◽  
John Maynard ◽  
Peter Gallagher ◽  
David Lozano ◽  
Patrick Butler
Keyword(s):  
Building Blocks ◽  
Biological Properties ◽  
Mirror Image ◽  
Symmetry Properties ◽  
Covalently Bonded ◽  
Axially Chiral ◽  
Mechanical Bond ◽  
A Chain ◽  
Lord Kelvin ◽  
Molecular Rings

Abstract The term chiral was introduced by Lord Kelvin over a century ago to describe objects that are distinct from their own mirror image. Chirality is relevant in many scientific areas, but particularly chemistry because different mirror image forms of a molecule famously have different biological properties. Chirality typically arises in molecules due to a rigidly chiral arrangement of covalently bonded atoms. Less generally appreciated is that molecular chirality can arise when molecules are threaded through one another to create a mechanical bond. For example, when two molecular rings with chemically distinct faces are joined like links in a chain the resulting structure is chiral even when the rings themselves are not. We re-examined the symmetry properties of such mechanically axially chiral catenanes and in doing so identified a straightforward route to these molecules from simple building blocks. This also led to the discovery of a previously overlooked mechanical stereogenic unit that can arise when such a ring encircles a dumbbell-shaped axle to generate a rotaxane. These insights allowed us to produce the first highly enantioenriched axially chiral catenane and the same approach gave access to a molecule containing the newly identified noncanonical axially chiral rotaxane motif. With methods to access these structures in hand, the process of exploring their properties and applications can now begin.

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