Sentences with phrase «by hydrogen bonds»

DNA (DeoxyriboNucleic Acid) a molecule composed of two chains of nucleic acid bases held together by hydrogen bonds in a pattern resembling a flexible twisted ladder.

Why it matters: At high pressures and low temperatures, like those found in permafrost or on the ocean's floor, water molecules organize into complex hydrate lattices that are held together by hydrogen bonds.

P1 behavior was first investigated by STM at the liquid / solid interface: as an exemple, an arrangement of the molecules on HOPG presenting a quasi-square lattice (a = 2.1 nm, b = 2.2 nm, α = 94 °) self - assembled by hydrogen bonds between the pyridine unit and the methyl groups borne by the p - xylene core will be described, indicating strong intermolecular interactions between the molecules P1 leading to a supramolecular self - assembly independent of the underlying HOPG structure.

These protein crystals are held together by hydrogen bonds, one of the weakest chemical bonds, and have an important role in defining the mechanical properties of silk.

When water (H2O) freezes into ice, the molecules are bound together in a crystalline lattice held together by hydrogen bonds.

In this salt, dihydrogenphosphate chains run through the crystal, held together by hydrogen bonds.

When the water is drained away Berglund found that the fibres join together into networks held by hydrogen bonds, forming flat sheets of «nanopaper».

On the atomic level, the layers are joined together by hydrogen bonds.

Water molecules are linked together by hydrogen bonds that break and form several thousands of billions of times per second.

In the double - helix configuration, two strands of DNA are joined to each other by hydrogen bonds in an arrangement known as base pairing.

Not exact matches

The diamond - like structural unit consists of six - sided rings of carbon atoms bonded together in chains surrounded by a halo of hydrogen atoms.

BY AFFECTING the way molecules bind to each other, hydrogen bonds are responsible for water's high boiling point, ice's propensity to float and DNA's signature double helix.

In principle, the wave function, denoted by Greek letter psi, can be used to reveal these energy levels for any given atom or molecule, although in practice this has only been done for the very simplest — the hydrogen atom and molecule (made of two hydrogen atoms bonded together).

Like water, it is held together by the powerful bonds between hydrogen and oxygen atoms, so ethanol can not travel through most petroleum pipelines.

The rays do this by causing molecules in the ring known as amide groups to shuffle from opposite sides of the carbon bond to the same side, loosening hydrogen bonds in the process.

Hydrogen atoms which diffuse inside the cages only bond weakly to them, so the gas can be recovered simply by heating the material slightly.

Ethylene (or IUPAC name ethene) is the simplest alkene hydrocarbon, consisting of four hydrogen atoms and two carbon atoms connected by a double bond.

You report on the redefinition by the International Union of Pure and Applied Chemistry (IUPAC) of hydrogen bond participants to...

First, the chemists release the hydrogen from its bonds with carbon by mixing methane with oxygen, throwing in a catalyst, and turning up the heat.

It turned out that the negative compressibility of sodium amidoborane crystals has to be a consequence of the elongation of the chemical bonds between nitrogen and hydrogen and boron and nitrogen, caused by the abrupt formation of new hydrogen bonds between adjacent molecules in the crystal.

The components are held together by relatively weak and reversible interactions — e.g., hydrogen bonding and aromatic stacking.

Atoms of most elements, such as hydrogen, oxygen and carbon, form tight chemical bonds by sharing electrons with their neighbours in order to give each atom a stable configuration of electrons.

DNA sequence discrimination by CAP derives both from sequence - dependent distortion of the DNA helix and from direct hydrogen - bonding interactions between three protein side chains and the exposed edges of three base pairs in the major groove of the DNA.

In a hair strand, the keratin molecules are mainly held together by two forces: chemical cross-links between cysteines (a type of amino acid) and weaker hydrogen bonds.

The hydrogen bonds can be disrupted by water vapor in the air, with each keratin binding to water in the air instead of each other.

These are stabilised mainly by weak interactions — such as hydrogen bonds, intramolecular interactions, and inter molecular dispersive forces, — between the backbone and the lateral chain of their amino acids.

So researchers are looking for materials that can stabilise hydrogen by weakly bonding with it.

While the strong sigma or covalent bonds were explained by the new theories of quantum mechanics, hydrogen bonds were seen as nothing more than an electrostatic attraction between charged particles and were explained according the principles of classical physics.

Also, the pressure exerted on the water is so high that hydrogen bond interactions with the graphene surface are overcome by the attractive van der Waals atomic interaction that draws together the graphene planes.

When combined with hydrogen peroxide, TAMLs neutralize many contaminants by breaking their chemical bonds.

This fact, along with the computer simulation, suggests that the mechanical force provided by actin can restructure CPEB into a longer fiber with new hydrogen bonds between the coils.

Intramolecular insertion of metal nitrenes into carbon - hydrogen bonds to form γ - lactam rings has traditionally been hindered by competing isocyanate formation.

«Water could be the most abundant source of hydrogen if one could separate the hydrogen from its strong bond with oxygen in the water by using a catalyst.»

This reveals the subtle balance between hydrogen bonding and the adhesion imparted by such polyphenolic compound.

«The Ru catalyst precisely distinguishes butadiene and substituted acetylene molecules and new carbon - carbon bonds are formed among a butadiene with two acetylenes just by migration of the terminal hydrogen atoms in butadiene.

Inside the AlloSphere, researchers such as Van de Walle use a joystick to maneuver through three - dimensional constellations of the oxygen, hydrogen and zinc atoms (linked by a complex lattice of chemical bonds) that make up these conductors.

All of them are shown to be affected by a single protein in their picosecond hydrogen bond dynamics

Whereas the first is explained by H - bond with the proteins, the retarded hydrogen bond dynamics around hydrophobic residues is at first glance surprising and can be explained by the additional imposed steric constraints on the water molecules at hydrophobic sites.

However, by stacking large numbers of these sheets, spider silk fails «gracefully», with the hydrogen bonds breaking one by one under an external force.

Thus, we designed and synthesized new molecular architectures based on the 3D Janus tecton concept, suitable for self - assembly on surface by supramolecular interactions such as coordination, halogen bond or hydrogen bond.3 Here we present two different model pyridyl end - capped molecules: the pedestal P1, and the naked pillar NP pedestal incorporating a cyclophane core.

Almost as clearly as a textbook diagram, this image made by a noncontact atomic force microscope reveals the positions of individual atoms and bonds, in a molecule having 26 carbon atoms and 14 hydrogen atoms structured as three connected benzene rings.

Hydrogen - bond acidic polymers are most widely used on acoustic wave sensors, which use sound waves in quartz chips to detect the vapors that are absorbed by the polymer.

Protein - protein complexes show good complementarity in surface shape and polarity and are stabilized largely by weak interactions, such as burial of hydrophobic surface, hydrogen bonds, and van der Waals forces.

For instance, the calcium hydride molecular ion (made of one calcium ion and one hydrogen ion bonded together) used by NIST in their experiments has 100 possible rotational states.

The enzyme, Tang's team reports, resembles the video - game character «Pac - Man,» with two bowl - shaped halves joined by a hinge at one end and held closed, most of the time, by a latch of hydrogen bonds on the other end.

Saturated: A fatty acid is saturated when all available carbon bonds are occupied by a hydrogen atom.

For example, the hydrogen bonding interaction between the phenolic — OH and the o - methoxy groups in curcumin influences the O - H bond energy and H atom abstraction by free radicals, thus making it a better scavenger of free radicals compared to other curcuminoids such as BDMC.

They differ from saturated fats by having fewer hydrogen atoms bonded to their carbon chains.

Saturated fats like coconut oil and tallow, are extremely stable because they pack together tightly courtesy of very straight carbon bonds that are all occupied by hydrogen atoms.

Your style will stay in place until these temporary hydrogen bonds are broken by moisture leaving or entering the hair shaft.