Sentences with phrase «carbon hydrogen bond»

«The key is to tune the shape of the template to create a subtle bias towards the targeted carbon hydrogen bond,» said Yu.

Not exact matches

Methane — a compound made up of one carbon atom bonded to four of hydrogen — is, according to the Intergovernmental Panel on Climate Change, 25 times as potent as carbon dioxide.

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

They are called saturated because hydrogens fill all the bonds in the carbons, soaking the molecule in hydrogen.

They are also all saturated fats, chains of single - bonded carbon atoms with hydrogen atoms neatly lined up on either side of each carbon.

But when the music stops, the hydrogens go back to bind again to the carbons, and they don't always come down in the same positions on the remaining double bonds.

Another major advantage the catalysts have is that, while they are general in what substrate they can oxidize, they are very specific about which carbon - hydrogen bonds they cut — so much so that they target a certain spot on amino acids like proline, leucine or valine even when they are part of a much larger peptide chain.

White's group is working on catalysts that can modify a wider range of amino acids, particularly those with electron - rich aromatic functionality, which compete with the carbon - hydrogen bonds for oxidation using the current catalyst.

A main advantage to the catalysts, which oxidize bonds between carbon and hydrogen, is that they preserve the amino acid's sense of chirality.

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.

At this temperature, the pressure in the reactor reaches 34 atmospheres, helping to break down the bonds between the hydrogen and carbon atoms in the polymer chains.

Complex organic molecules, consisting of carbon bonded with other elements like oxygen and hydrogen, are common in the Milky Way, but it was uncertain whether they would be produced in certain dwarf galaxies like the neighboring Large Magellanic Cloud.

About four billion years ago, the strength of those hydrogen - carbon bonds allowed increasingly complex molecules — amino acids, DNA, and proteins — to form from the primordial soup, making life possible.

Free radicals attack weak carbon - hydrogen bonds and are a major source of the kind of oxidative cell damage that can occur in conditions such as coronary artery disease, neurological disorders and retinal ailments.

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

He has spent his career focused on just one bond, a link between a carbon and a hydrogen atom in a molecule of methane, the main component of natural gas.

They make good fuels because the energy stored in the bonds between carbon and hydrogen is abundant and easy to release in combustion with oxygen.

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.

Instead of a hydrophilic alcohol group (an oxygen - hydrogen molecule bound to a hydrogen - saturated carbon atom), the final lignin polymer contained a hydrophobic aldehyde group (a carbon atom double - bonded to an oxygen atom).

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.

The amalgamation of these techniques provided a fully characterized structure, one in which the dissolved carbon dioxide acts as a hydrophobe, having formed only very weak hydrogen bonds to the surrounding water molecules.

Scientists from Tomsk Polytechnic University together with their colleagues from USA and Japan have proposed a novel way to address the most important and fundamental challenge of organic chemistry, i.e. breaking a bond between carbon and hydrogen atoms to form new organic substances.

In order to obtain new compounds, it is necessary to break the bond of carbon and hydrogen to form carbon - carbon bond,» explains the researcher.

«Unsaturated hydrocarbons contain only two types of bonds, carbon - hydrogen and carbon - carbon.

Herein we demonstrate that a photoredox - mediated hydrogen atom transfer protocol can efficiently and selectively install deuterium (D) and tritium (T) at α - amino sp3 carbon - hydrogen bonds in a single step, using isotopically labeled water (D2O or T2O) as the source of hydrogen isotope.

«Hydrocarbons — compounds made out of carbon and hydrogen or having a carbon - hydrogen bond — are used in daily life all the time — from clothes to toothbrushes,» said Partha Basu, chair and professor of chemistry and biological chemistry at IUPUI.

These elements helped to carry out CH - activation, i.e. to break the bond between carbon and hydrogen in molecules and to create a new carbon - carbon bond and thereby obtain new promising substances.

As the water boiled away, the hydrogen escaped into interstellar space while the oxygen came back down and bonded with carbon atoms.

This lack of oxygen enables them to maintain their hydrogen - carbon bonds, a necessary ingredient for the production of oil and gas.

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

Melanie Sanford, a chemist the University of Michigan, Ann Arbor, who focuses on using metal - based agents, primarily palladium, to catalyze reactions that substitute hydrogen in carbon - hydrogen bonds with other atoms or functional groups.

For example, instead of stealing an electron from double - bonded carbons or a nearby propagating chain, the carbon atom with the free radical sometimes steals an entire hydrogen atom from another chain end.

Trinuclear copper - oxo clusters were identified that exhibit a high reactivity towards activation of carbon - hydrogen bonds in methane and its subsequent transformation to methanol.

Polyethylene consists of a chain of single - bonded carbon atoms, each still carrying its two hydrogen atoms.

The result was a picture of the bonds linking the carbon and hydrogen atoms that make up the flat molecule pentacene.

For example, questions such as «What happens to the rest of the bonds in a chain of carbon rings if you pinch a hydrogen atom off the end?»

Instead, Wang and his colleagues identified a relationship between a feature of the bonds linking carbon and hydrogen in methane molecules — a quality they deemed «clumpiness» — and the rate at which methane was produced: The clumpier the bond, the slower the rate of methanogenesis.

At that temperature, carbonate (a weak, non-hazardous base) can break the hydrogen - carbon bond.

When carbon dioxide gas entered the mix, the gas molecules broke hydrogen bonds in the water molecules, making the ice more brittle.

«Cheap, energy - efficient and clean reaction to make chemical feedstock: Combining experimental and computer chemistry, scientists find the conditions to break carbon - hydrogen bonds at low temperature with cheap titanium in place of rare metals.»

Natural gases, such as methane and ethane, have strong carbon - hydrogen (C - H) bonds that are difficult to break.

Again, the first one stripped off hydrogens from adjacent carbon atoms in both the long polyethylene chains and short alkanes to form double bonds; the second split the molecules and randomly stitched split molecules back together.

These are simulated crystal structures of virgin - DEB and T4H - DEB (chemically known as 1,4 - distyrylbenzene, a trans - isomer of DEB intermediate product after the capture of first 4 atomic hydrogen with 2 CH bonds on opposing sides of the carbon chain).

Now, researchers have explored how and why this volatility varies during hydrogenation, suggesting that a previously underappreciated effect from carbon - hydrogen bonds in the molecule is the main culprit.

He knew he needed to find metals that were deft at breaking the carbon - hydrogen bonds that are at the heart of methane, ethane, and propane, short hydrocarbons known as alkanes, and then add in oxygen atoms that would transform the alkanes into alcohols.

According to conventional thought, the resulting carbon - hydrogen bond is nonpolar — neither end of the barbell structure is more negatively or positively charged than the other.

Their analysis suggests that the carbon - hydrogen bonds in DEB play a key role in the molecule's volatile behavior.

Previous research had overlooked these collective interactions among carbon - hydrogen bonds in organic crystals, Dinh said.

«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.

Depending on how the carbon - hydrogen bonds are arranged and how many there are in the intermediate DEB products, the molecules can either attract or repel one another, and thus be less or more volatile, respectively.