An orthogonal approach to the creation of multiple nanoscale templates from a single supramolecular block copolymer system is presented. The enabling feature of this strategy is the design of block copolymers that incorporate independent degradation chemistries which permits each block copolymer to be addressed individually and sequentially. By blending a block copolymer containing H-bond donor...

In dynamic force spectroscopy, a (bio-)molecular complex is subjected to a steadily increasing force until the chemical bond breaks. Repeating the same experiment many times results in a broad distribution of rupture forces, whose quantitative interpretation represents a formidable theoretical challenge. In this study we address the situation that more than a single molecular bond is involved i...

Photocatalysis has recently opened up new avenues for the generation of radical species under visible light irradiation conditions. A particularly fascinating class of photocatalyzed transformations relies on the activation of stable boron species with visible-light since it allows the creation of boryl and/or carbon radicals through single electron transfer or energy transfer without the need ...

A new mechanism of H2 activation is reported to occur on a carbene-ligated rhodathiaborane that features metal-thiaborane bifunctional synergistic effects. The key is the creation of vacant coordination sites by an isonido-nido structural transformation leading to the heterolytic H-H bond splitting.

Rhodium-catalyzed intramolecular alkynylsilylation of alkynes is described. The reaction proceeds through syn-insertion by a cationic rhodium/triarylphosphine catalyst, representing the first alkynylsilylation of alkynes via the cleavage of a C(sp)-Si bond by transition-metal catalysis. A highly enantioselective variant is also described for the creation of a silicon stereogenic center.

This study investigated the influence of the composition of self-etching primer adhesive systems on the morphology of acid-base resistant zones (ABRZs). One-step self-etching primer systems (Clearfil Tri-S Bond, G-Bond, and One-Up Bond F Plus) and two-step self-etching primer systems (Clearfil SE Bond, Clearfil Protect Bond, UniFil Bond, and Mac Bond II) were used in this study. Each adhesive w...

BACKGROUND When partial coverage restorations (veneers, inlays, onlays…) must be cemented to dentin, bond strength may not reach the same predictable values as to enamel. The purpose of this study was: 1. To compare, with a shear bond test, the bond strength to dentin of a total-etch and a self-etching bonding agent. 2. To determine whether creating microretention improves the bond strength to ...

The chemical bond arises from a redistribution of electronic charge when atoms are brought in close proximity. The bond in a solid results from the superposition of charge densities of all atoms in the system. In an atom all electrons reside in their ground states at equilibrium. Only a few low lying excited states are typically accessed. The chemical bond in the solid consists of excited elect...

In the same way that gases react with surfaces from above, solid-state point defects such as interstitial atoms can react from below. Little attention has been paid to this form of surface chemistry. Recent bulk selfdiffusion measurements near the Si 100 surface have quantified Si interstitial annihilation rates, and shown that these rates can be described by an annihilation probability that va...

In this paper we examine a series of hydrocarbons with structural features which cause a weakening of the C-H bond. We use theoretical calculations to explore whether the carbon-centered radicals R(*) which are created after breaking the bond can be stabilized enough so that they resist the addition of molecular oxygen, i.e. where the reaction R(*) + O(2) --> ROO(*) becomes energetically unfavo...