| 单词 | chemical bond |
| 例句 | Using only the most abundant gases that were present on the early Earth and almost any energy source that breaks chemical bonds, we can produce the essential building blocks of life. Cosmos 1980-01-01T00:00:00Z “British brains dream up a chemical bond stronger than gravity!” Black Swan Green 2006-04-10T00:00:00Z Unlike the other constituents, they obeyed no simple-minded rules telling us the angles at which they would form their respective chemical bonds. Double Helix 1968-02-27T00:00:00Z But since the linkages between the nucleotides involved only the phosphate and sugar groups, our assumption that the same type of chemical bond linked all the nucleotides together was not affected. Double Helix 1968-02-27T00:00:00Z Schrödinger imagined a chemical with multiple chemical bonds stretching out along the length of the “chromosome fiber.” The Gene 2016-06-02T00:00:00Z The team say that the pH-sensitive adhesive system could serve as a novel, and recyclable, middle ground between structural adhesives with fixed chemical bonds and peel-off adhesive films that bond using physical interactions. Recycling of water-based adhesive achieved by changing pH 2023-11-13T05:00:00Z The polyurethanes created here have new 'dynamic' chemical bonds, which means that despite their thermoset structure, they can be reshaped by exchanges of chemical bonds under relatively mild reaction conditions. Capture or reuse CO2 as a chemical source for the production of sustainable plastics 2023-11-13T05:00:00Z Developing new ways to break and reform chemical bonds is one of the main tasks of basic chemical research. Charged 'molecular beasts' the basis for new compounds 2023-11-03T04:00:00Z Named VPR, the material can hold its form and has strong internal chemical bonds at low temperatures. Stronger, stretchier, self-healing plastic 2023-11-02T04:00:00Z The hardness of materials is determined by the strength of the chemical bonds that are formed between the electrons of the neighbouring atoms. Conduction electrons drive giant, nonlinear elastic response in Sr2RuO4 2023-10-26T04:00:00Z Structural adhesive systems, such as two-component adhesives, form chemical bonds when they react and cannot be separated again along the adhesive interface. Recycling of water-based adhesive achieved by changing pH 2023-11-13T05:00:00Z These chemical reactions are indispensable for forming essential chemical bonds during the synthesis of a chemical compound. Novel catalyst for green production of fine chemicals and pharmaceuticals 2023-10-13T04:00:00Z To create the desired chemical bonds with a high yield, chemists usually implement complex, multi-step strategies involving numerous intermediates. An electrical switch to control chemical reactions 2023-10-12T04:00:00Z Nature stores energy in chemical bonds, and hydrogen contains the highest energy density in relation to its weight. New catalyst could provide liquid hydrogen fuel of the future 2023-10-12T04:00:00Z For one, breaking a chemical bond is a fundamental process in nature where electrons that are shared between two atoms separate out into unbound atoms. What is an attosecond? A physical chemist explains the tiny time scale that earned a Nobel prize 2023-10-10T04:00:00Z Well, hair proteins contain many permanent chemical bonds. Why Hair Turns Curly and Frizzy in the Summer, according to Chemistry 2023-08-16T04:00:00Z He received his Nobel Prize in 1992 for work on electron transfer reactions, a deceptively simple theory describing how electrons move between molecules in chemical reactions without breaking chemical bonds. A Caltech Nobel laureate celebrates his 100th birthday. Then he gets back to work 2023-07-21T04:00:00Z These bonds form when an electron is shared between two elements and are the strongest and most common form of chemical bond in living organisms. Concepts of Biology 2013-04-25T00:00:00Z But the chemical bonds that make up plastics are made to last and, of the seven billion tonnes ever created, less than 10% has been recycled. Could waste plastic become a useful fuel source? 2023-03-13T04:00:00Z The previously shared electrons undergo ultrafast changes during this process, and attosecond pulses made it possible for researchers to follow the real-time breaking of a chemical bond. What is an attosecond? A physical chemist explains the tiny time scale that earned a Nobel prize 2023-10-10T04:00:00Z Scientists started looking at hydrogen mixed with one other element, surmising that the chemical bonds might help compress the hydrogen atoms. A Room-Temperature Superconductor Discovery Aims to Overcome Resistance 2023-03-08T05:00:00Z And they perform better than previous efforts because they form tighter chemical bonds, the researchers say, maintaining their structure and function in conditions where DNA and RNA enzymes unfurl. Lab-Made Enzymes Could Chop Up the Virus That Causes COVID 2023-02-20T05:00:00Z Which type of bond represents a weak chemical bond? Concepts of Biology 2013-04-25T00:00:00Z Now the race is on to find the best way to break those chemical bonds and reclaim the Earth's precious resources locked into plastic. Could waste plastic become a useful fuel source? 2023-03-13T04:00:00Z By providing shorter snapshots of atoms and molecules, attosecond spectroscopy has helped researchers understand electron behavior in single molecules, such as how electron charge migrates and how chemical bonds between atoms break. What is an attosecond? A physical chemist explains the tiny time scale that earned a Nobel prize 2023-10-10T04:00:00Z Proteins are, in essence, chains of amino acids linked together by chemical bonds. The water paradox: How did the first life form in a hostile liquid? 2022-11-15T05:00:00Z One of the things we built in was this understanding of chemical bond angles and also evolutionary history using a process called multisequence alignment. One of the Biggest Problems in Biology Has Finally Been Solved 2022-10-31T04:00:00Z A molecule is a chemical structure consisting of at least two atoms held together by a chemical bond. Concepts of Biology 2013-04-25T00:00:00Z Just milliseconds later, when the molecules pinged the mass spectrometer, they had formed chemical bonds called dipeptides. Ocean spray may have created conditions for life to form on Earth, new study suggests 2022-10-07T04:00:00Z A recent theoretical analysis of the chemical bonds holding DNA together, however, suggests that these effects might occur far more frequently than once thought—and act as a major source of genetic mutations. Quantum Tunneling Makes DNA More Unstable 2022-09-21T04:00:00Z For best results, apply the finish paint within hours of the primer drying to get the best mechanical and chemical bond between the two linked layers! Ask the Builder: Time-tested exterior painting secrets 2022-09-20T04:00:00Z For best results, apply the finish paint within hours of the primer drying to get the best mechanical and chemical bond between the two linked layers. Perspective | How to get the best result when painting exterior wood 2022-09-07T04:00:00Z Because of these vacancies in the outermost shells, we see the formation of chemical bonds, or interactions between two or more of the same or different elements that result in the formation of molecules. Concepts of Biology 2013-04-25T00:00:00Z It's more like jostling a sack full of magnetic Legos, which fit together easily and are attracted to each other through chemical bonds. Ocean spray may have created conditions for life to form on Earth, new study suggests 2022-10-07T04:00:00Z Damage to DNA consists of breaks in chemical bonds or other changes in the structural features of the DNA chain, leading to changes in the genetic code. College Physics for AP Courses 2015-08-12T00:00:00Z Thinking in terms of overlapping atomic orbitals is one way for us to explain how chemical bonds form in diatomic molecules. Chemistry 2019-02-14T00:00:00Z Protein shape is critical to its function, and this shape is maintained by many different types of chemical bonds. Biology for AP Courses 2022-06-09T00:00:00Z Chemical reactions involve changes in the chemical bonds that join atoms in compounds. Miller & Levine Biology 2018-01-01T00:00:00Z These chemical bonds store this energy for later use in the process of respiration. Environmental Biology 2018-09-06T00:00:00Z For elements that do not have a full outer shell, the outermost electrons can interact with the outermost electrons of nearby atoms to create chemical bonds. Physical Geology 2015-01-01T00:00:00Z In comparison to chemical bond energies, nuclear binding energies are vastly greater, as we will learn in this section. Chemistry 2019-02-14T00:00:00Z The proteins that perform that task interact with the polymer without forming new chemical bonds. Biology for AP Courses 2022-06-09T00:00:00Z Whenever chemical bonds are formed or broken, energy is released or absorbed. Miller & Levine Biology 2018-01-01T00:00:00Z The fact that energy can be released by the breakdown of certain chemical bonds implies that those bonds have potential energy. Environmental Biology 2018-09-06T00:00:00Z Compounds that are held together by chemical bonds are called molecules. An Introduction to Geology 2017-01-01T00:00:00Z When this radiation encounters living cells, it can cause heating, break chemical bonds, or ionize molecules. Chemistry 2019-02-14T00:00:00Z However, increasing or decreasing the temperature outside of an optimal range can affect chemical bonds within the active site in such a way that they are less well suited to bind substrates. Biology for AP Courses 2022-06-09T00:00:00Z As the candle burns, chemical bonds between carbon and hydrogen atoms in the wax are broken. Miller & Levine Biology 2018-01-01T00:00:00Z The type of potential energy that exists within chemical bonds, and is released when those bonds are broken, is called chemical energy. Environmental Biology 2018-09-06T00:00:00Z With 11 positively charged protons in the nucleus and 10 negatively charged electrons in two shells, sodium when forming chemical bonds is an ion with an overall net charge of +1. An Introduction to Geology 2017-01-01T00:00:00Z For example, alpha and beta particles emitted from nuclear decay reactions possess much higher energies than ordinary chemical bond energies. Chemistry 2019-02-14T00:00:00Z These chemical bonds thereby store this energy for later use in the process of respiration. Biology for AP Courses 2022-06-09T00:00:00Z These new bonds are at a lower energy state than the original chemical bonds in the wax. Miller & Levine Biology 2018-01-01T00:00:00Z Atoms combine to form molecules, which are chemical structures consisting of at least two atoms held together by a chemical bond. Environmental Biology 2018-09-06T00:00:00Z If the vibrations are violent enough, chemical bonds are broken and the crystals melt releasing the ions into the melt. An Introduction to Geology 2017-01-01T00:00:00Z We will discuss chemical bonds and see how to predict the arrangement of atoms in a molecule later. Chemistry 2019-02-14T00:00:00Z Which type of bond exemplifies a weak chemical bond? Biology for AP Courses 2022-06-09T00:00:00Z All living cells store energy in the chemical bonds of certain compounds. Miller & Levine Biology 2018-01-01T00:00:00Z Covalent bonds are the strongest and most common form of chemical bond in organisms. Environmental Biology 2018-09-06T00:00:00Z A compound is a substance composed of two or more elements joined by chemical bonds. Anatomy and Physiology 2013-06-19T00:00:00Z In this section, we will explore the typical method for depicting valence shell electrons and chemical bonds, namely Lewis symbols and Lewis structures. Chemistry 2019-02-14T00:00:00Z During chemical reactions, certain chemical bonds are broken and new ones are formed. Biology for AP Courses 2022-06-09T00:00:00Z The atoms in compounds are held together by chemical bonds. Miller & Levine Biology 2018-01-01T00:00:00Z One such mechanism, called methylation, involves a methyl group—a methane molecule that is missing one of its four hydrogen atoms, leaving a chemical bond free to attach to another atom or molecule. How Parents’ Trauma Leaves Biological Traces in Children 2022-06-25T04:00:00Z A more or less stable grouping of two or more atoms held together by chemical bonds is called a molecule. Anatomy and Physiology 2013-06-19T00:00:00Z A molecule consists of two or more atoms joined by strong forces called chemical bonds. Chemistry 2019-02-14T00:00:00Z You’ve learned that the activation energy required for many reactions includes the energy involved in manipulating or slightly contorting chemical bonds so that they can easily break and allow others to reform. Biology for AP Courses 2022-06-09T00:00:00Z The main types of chemical bonds are ionic bonds and covalent bonds. Miller & Levine Biology 2018-01-01T00:00:00Z Yet within a millisecond every protein in an organism will fold into its very own specific shape – the lowest-energy arrangement of all the chemical bonds that make up the protein. A celebrated AI has learned a new trick: How to do chemistry 2022-06-20T04:00:00Z Chemical energy is the form of potential energy in which energy is stored in chemical bonds. Anatomy and Physiology 2013-06-19T00:00:00Z The ability of an atom to attract a pair of electrons in a chemical bond is called its electronegativity. Chemistry 2019-02-14T00:00:00Z A molecule is a chemical structure consisting of at least two atoms held together by one or more chemical bonds. Biology for AP Courses 2022-06-09T00:00:00Z Weak Interactions The strongest chemical bonds are ionic or covalent. Miller & Levine Biology 2018-01-01T00:00:00Z Progress was swift because in each case, these so-called biopolymers come together from a relatively small number of building blocks that can all be linked by making the same chemical bond. Machine builds druglike organic molecules in a snap 2022-02-08T05:00:00Z Chemical reactions, in which chemical bonds are broken and formed, require an initial investment of energy. Anatomy and Physiology 2013-06-19T00:00:00Z Atoms must be close together to form chemical bonds. Chemistry 2019-02-14T00:00:00Z Logically, when two atoms chemically bond to form a molecule, their electrons, which form the outermost region of each atom, come together first as the atoms form a chemical bond. Biology for AP Courses 2022-06-09T00:00:00Z The metals caused carbon bonds in molecules to break apart and then rearrange themselves in different ways, creating new chemical bonds. Robert H. Grubbs, Nobel laureate in chemistry, dies at 79 2021-12-25T05:00:00Z Cusack, Hadden-Paton and Sella are accorded only bare outlines of characters; other than their chemical bond — and a few whiffs of sexual attraction — no interesting connections are forged in their encounters. Review | Broadway’s ‘Flying Over Sunset’ comes in for a crash landing 2021-12-13T05:00:00Z Instead, atoms link by forming a chemical bond. Anatomy and Physiology 2013-06-19T00:00:00Z Ionizing radiation is the most harmful because it can ionize molecules or break chemical bonds, which damages the molecule and causes malfunctions in cell processes. Chemistry 2019-02-14T00:00:00Z The electrons of the outermost energy level determine the energetic stability of the atom and its tendency to form chemical bonds with other atoms to form molecules. Biology for AP Courses 2022-06-09T00:00:00Z Hydrogels are made of polymer strands that stick together in two ways: chemical bonds known as cross-links, and entanglements, in which one polymer chain weaves around another. This long-lasting hydrogel could be used to replace damaged human tissues 2021-11-02T04:00:00Z When UV light gets absorbed, the photons of light transfer their energy to and damage the chemical bonds of the genetic material. The ultraviolet light most effective at killing coronavirus is also the safest to use around people 2021-11-01T04:00:00Z Each moment of life, atoms of oxygen, carbon, hydrogen, and the other elements of the human body are making and breaking chemical bonds. Anatomy and Physiology 2013-06-19T00:00:00Z The chemical bonds are so strong that they don’t degrade or do so only slowly in the environment and remain in a person’s bloodstream indefinitely. EPA unveils strategy to regulate toxic ‘forever chemicals’ 2021-10-18T04:00:00Z However, since not all elements have enough electrons to fill their outermost shells, atoms form chemical bonds with other atoms thereby obtaining the electrons they need to attain a stable electron configuration. Biology for AP Courses 2022-06-09T00:00:00Z They chose to simulate a chain of point masses connected by springs, designed to represent atoms connected by chemical bonds, then observe what happened to energy as it moved around on the chain. An Unsung Female Pioneer of Computer Simulation 2021-09-29T04:00:00Z These break chemical bonds in the plastic's molecules, like a jeweler snipping bracelet links. Tiny Robots Could Clean Up Microplastic Pollution 2021-09-14T04:00:00Z The chemical bond between the second and third phosphate groups, termed a high-energy bond, represents the greatest source of energy in a cell. Anatomy and Physiology 2013-06-19T00:00:00Z The chemical bonds that held you together at the molecular level continue to break in the minutes and months after you die. Opinion | What Is Death? 2020-12-18T05:00:00Z Molecules that share the same chemical bonds but are mirror images of each other. Biology for AP Courses 2022-06-09T00:00:00Z Perhaps someday we will harness the power of nature and use chemical bonds and biological materials to do our labor for us. September 2020: The Art and Science of Efficient Manufacturing 2020-09-26T04:00:00Z Because the chemical bonds that hold the compounds together don’t break down easily, they last a very long time – a reality that has led to a commonly used name for the group: “Forever chemicals.” Why dangerous ‘forever chemicals’ are allowed in US drinking water 2020-09-24T04:00:00Z She and her colleagues are exploring whether adding compounds called oxalates will speed this process further by weakening chemical bonds in the tailings. Industrial waste can turn planet-warming carbon dioxide into stone 2020-09-03T04:00:00Z The small part of the observatory that I’m working on is the glue-free chemical bond used to attach the fibres to the mirrors. Measuring ripples in the curvature of space-time 2020-07-26T04:00:00Z Since heat helps to break the chemical bonds in plastic, it’s possible that exposure to high temperatures increases the rate of chemical migration from the container into the food. Are plastic containers safe for our food? Experts say it’s hard to know 2020-02-18T05:00:00Z The drug sulfasalazine, widely used for rheumatoid arthritis, Crohn's disease and ulcerative colitis, does nothing unless gut bacteria metabolize it into an active form by breaking a chemical bond. How Gut Microbes Shape Our Response to Drugs 2020-01-19T05:00:00Z Just like polymers, wood contains chemical bonds that emit the right kind of infrared radiation, says Li. The super-cool materials that send heat to space 2019-12-30T05:00:00Z Those that are sufficiently energetic to eject electrons from an atom and cleave chemical bonds are known as ionizing radiation. Don't Fall Prey to Scaremongering about 5G 2019-10-28T04:00:00Z When the material is exposed to green LED light, its chemical bonds strengthen to produce a hard, stable structure. Nine universities under 50 in the fast lane 2019-10-22T04:00:00Z It uses laser light to identify the types of chemical bonds in a sample. Warm-blooded velociraptors? Fossilized proteins unravel dinosaur mysteries 2019-10-08T04:00:00Z You talk about hate in terms of chemical bonds and “gelation theory”. The physics professor who says online extremists act like curdled milk 2019-08-23T04:00:00Z Their internal chemistry uses visible and ultraviolet light to break chemical bonds and digest essential molecules, while rejecting infrared photons that are not energetic enough to be useful in this process. In Search of Green Dwarfs 2019-06-03T04:00:00Z Researchers believe that in that primordial gas, neutral helium reacted with hydrogen ions to form the first chemical bond joining the very first molecule. Astronomers have spotted the universe’s first molecule 2019-04-17T04:00:00Z For example, stability can be examined by calculating the total energy of electrons and ions in the given configuration; the lower the energy, the firmer the chemical bonds. Beware of plausible predictions of fantasy materials 2019-02-26T05:00:00Z She tracked fossilization reactions in her experiments with modern samples and concluded that the ratio of two key types of chemical bonds in a fossil's Raman spectrum might point to metabolic rate. Warm-blooded velociraptors? Fossilized proteins unravel dinosaur mysteries 2019-10-08T04:00:00Z In this case, the nanowires rearranged chemical bonds between carbon atoms, which is also what’s needed to convert methanol to ethanol. Ultraviolet light could provide a powerful new source of green fuel 2019-02-19T05:00:00Z In atoms, electrons occupy discrete, fuzzy clouds called orbitals that surround the nucleus, and those with the highest energy are the ones involved in forming chemical bonds and ions. Extreme chemistry: experiments at the edge of the periodic table 2019-01-29T05:00:00Z Many enzymes form covalent chemical bonds to the reacting molecule as part of their strategy for catalysing reactions. Enzymes engineered to trap reaction intermediates 2018-12-11T05:00:00Z Releasing oxygen from its chemical bonds is more energy-intensive than heating ice. How to build a Moon base 2018-10-23T04:00:00Z Then they heated the resin to temperatures as high as 200 degrees Celsius to cure it, forging strong chemical bonds. Scientists Create Artificial Wood That Is Water- and Fire-Resistant 2018-10-23T04:00:00Z And the technique previously used to decipher what atoms were present required busting the molecules apart, giving little insight into the chemical bonds that held them together in the first place. First "Photos" of Ocean Carbon Molecules Hold Clues to Future Warming 2018-08-08T04:00:00Z Restriction enzymes are often portrayed as molecular scissors because they cut chemical bonds in DNA. What is genetic modification? 2018-08-05T04:00:00Z Going down this group, from oxygen to sulfur to selenium, an atom’s tendency to attract electrons in a chemical bond towards itself decreases. Stable and switchable electric polarization in two dimensions 2018-07-29T04:00:00Z High-frequency light has sufficient energy to break apart chemical bonds, causing DNA damage. Why mobile phones are NOT a health hazard 2018-07-21T04:00:00Z And all that loose chlorine was tearing up the ozone layer, ripping up the chemical bonds of high-flying molecules that protect Earth’s surface from ultraviolet radiation. Earth's Ozone Layer is Under Attack--Again 2018-05-22T04:00:00Z If there is a ridge of electron density — like that associated with a chemical bond — tilting helps the atomic force microscope to obtain a clear contrast with the background. How atomic imaging is being pushed to its limit 2018-03-19T04:00:00Z “When you cut something with a knife, in the end, you’re cutting some chemical bonds,” Carroll said. Space X sent a cute red Tesla Roadster into space. Here’s what’ll probably happen to it 2018-02-08T05:00:00Z The heat melts the chemical bonds between the hydrogen and oxygen atoms. New Form of Water, Both Liquid and Solid, Is ‘Really Strange’ 2018-02-05T05:00:00Z The pressure and heat encourage the formation of chemical bonds between large numbers of hydrogen atoms and neighboring atoms in adjacent nanofibers of cellulose, greatly strengthening the material. Stronger Than Steel, Able to Stop a Speeding Bullet--It's Super Wood! 2018-02-07T05:00:00Z Wheat gluten—a protein from wheat flour commonly used as a meat substitute—may be able to rebuild broken chemical bonds in hair protein, according to a new study. Want to cure your hair’s split ends? Try washing them with wheat gluten 2018-02-06T05:00:00Z They’re uncovering the nature of chemosynthetic processes in caves — how microorganisms use energy from chemical bonds, rather than light energy as in photosynthesis, to produce organic matter — and their significance to the cave food web. A lot can go wrong when you’re a professor who does research by cave diving 2018-01-12T05:00:00Z She wanted to see evidence that the researchers’ novel molecules formed stable chemical bonds with cellulose. A Glowing Cotton Study That Might Have Deserved Less Glowing Reviews 2017-09-21T04:00:00Z Another possibility is that earthquake lights are a manifestation of triboluminescence, which refers to light released when chemical bonds are broken through rubbing, crushing or scratching. What caused the mysterious lights in the night sky after Mexico’s earthquake? 2017-09-15T04:00:00Z Scientists say the way it shines light on targets will permit, for example, chemical bonds to be filmed in the instant that they are made or broken. XFEL: Brilliant X-ray laser comes online - BBC News 2017-09-01T04:00:00Z However, by lowering the salt content of the water in the reservoir, BP thinks this will make the chemical bonds of that chain relax. Future energy: The technology allowing more oil extraction - BBC News 2017-07-12T04:00:00Z Doing this creates both a mechanical and chemical bond between the primer and finish coat of paint. Perspective | How to find paint for outdoor furniture that will last in harsh conditions 2017-05-29T04:00:00Z They also hooked their setup to a solar cell and showed that a record 13.4% of the energy in the captured sunlight was converted into the CO’s chemical bonds. Cheap catalysts turn sunlight and carbon dioxide into fuel 2017-06-06T04:00:00Z The act of forming, breaking, and reforming the chemical bond, he said, deepened the reading experience. Postscript: Frank Deford 2017-05-30T04:00:00Z Scientists discovered that the wax worm is able to break down the chemical bonds in polyethylene, a widely produced plastic used in packaging, bags and other everyday materials. A very hungry caterpillar may help slow plastic pollution, researchers say 2017-04-29T04:00:00Z Wax also contains a chemical bond found in polyethylene. These pesky caterpillars seem to digest plastic bags 2017-04-24T04:00:00Z The chemical bonds between the urea and hydroxyapatite molecules prevent the urea from decomposing too quickly. ‘Slow-release’ fertilizer boosts crop yields, reduces environmental damage 2017-02-03T05:00:00Z Over time, the salts may have hardened the wood through chemical bonds. The Brilliance of a Stradivari Violin Might Rest Within Its Wood 2016-12-20T05:00:00Z "Nickel behaves chemically in a way that is very similar to iridium; it loves to make strong chemical bonds with iron, just like iridium," he told BBC News. Team hunts tracer of 'dinosaur killer' asteroid - BBC News 2016-12-13T05:00:00Z Many of the hair relaxers and dyes contained lye which is used to break down chemical bonds in hair. Beauty Products Marketed to Black Women May Contain More Hazardous Chemicals: Report 2016-12-06T05:00:00Z The key to the work, Stoddart says, was the development of a new type of chemical bond, a mechanical linkage that allows components to interact in a controlled and repeated manner. Updated: World's smallest gadgets bag Nobel chemistry prize 2016-10-05T04:00:00Z The radiation breaks the gasses’ chemical bonds, forming radicals, which in turn, are broken apart and recombined by radiation. Why Pluto’s Moon Charon Wears a Red Cap 2016-09-14T04:00:00Z Many historians consider this to be the first scientific account of a catalyst: a material that speeds reactions by making or breaking chemical bonds, without being consumed. The new breed of cutting-edge catalysts 2016-09-05T04:00:00Z But they could not watch the actual dynamics of the process because the breaking and shifting of chemical bonds occurred too quickly. Ahmed H. Zewail, Nobel-Prize-Winning Chemist, Dies at 70 2016-08-05T04:00:00Z With such advances, it became possible to watch as chemical bonds formed, broke and formed again. Ahmed Zewail, Nobel laureate who sparked a ‘revolution in chemistry,’ dies at 70 2016-08-03T04:00:00Z It also sharply reduced the efficiency of converting the energy in the electricity to chemical bonds in the fuel. Microbe-linked solar panels are better than plants at converting sunlight to energy 2016-06-02T04:00:00Z In the 1850s, Kekulé developed the familiar chain-like representation of molecules using letters—indicating the constituent atoms—joined by lines representing “chemical bonds.” How Visionaries in Visualization Moved Science Forward 2016-05-06T04:00:00Z It opened the way to deep insights into atomic and molecular behavior, and into the formation of chemical bonds. Walter Kohn, onetime refugee who became Nobel laureate in chemistry, dies at 93 2016-04-24T04:00:00Z His theoretical research into atomic behavior and the formation of chemical bonds enabled scientists to develop new molecules that formed the basis for innovative materials custom designed for medicines and for advances in electronics. Walter Kohn, Nobel-Winning Scientist, Dies at 93 2016-04-25T04:00:00Z But if the temperature is raised above the plasticity threshold, then the TBD kicks in by creating chemical bonds between the polymer chains. New material can fold itself into hundreds of shapes 2016-01-08T05:00:00Z The repairs, she explained, involve the making and breaking of chemical bonds. Nobel Prize in chemistry shared by American, Swedish and Turkish scientists for DNA repair 2015-10-07T04:00:00Z “These mechanisms are fundamentally about the making and breaking of chemical bonds,” she said. Discovery of DNA Repair Methods Nails 2015 Chemistry Nobel Prize 2015-10-07T04:00:00Z The task essentially boils down to running combustion in reverse, injecting energy from the sun or other renewables into chemical bonds. Feature: There’s too much carbon dioxide in the air. Why not turn it back into fuel? 2015-09-10T04:00:00Z They nestle there, forming a temporary chemical bond that triggers the receptor to send its “HOT!” message through the nervous system. Scientists Expose The Molecular Origami Behind Chili Pepper Heat 2015-06-10T04:00:00Z Dr. Rich moved to the California Institute of Technology as a research fellow in the lab of Linus Pauling, who would receive the Nobel Prize in Chemistry in 1954 for his work on chemical bonds. Alexander Rich Dies at 90; Confirmed DNA’s Double Helix 2015-05-05T04:00:00Z In other words, she was “rearranging the chemical bonds of the glue to create a polymer,” said Talbott, president of Millikin’s student chapter of the American Chemical Society. EXCHANGE: Millikin chemistry students combine fun, science 2015-04-05T04:00:00Z Heating causes the weak chemical bonds that keep these proteins entangled to break. Shape-Shifting Science: Molding Hard-Boiled Eggs 2015-04-02T04:00:00Z So far, such setups aren’t very efficient; typically they convert less than 1% of the incoming solar energy into chemical bonds. Feature: There’s too much carbon dioxide in the air. Why not turn it back into fuel? 2015-09-10T04:00:00Z Not that this would be easy, since we’re talking about chemical bonds being broken. Solving The Super Weird Chemical Mystery Of Powdered Alcohol Drinks 2015-03-13T04:00:00Z No one knows why ultraviolet photons do not normally break the chemical bonds in the molecule when they hit it, but it is assumed that melanin’s electrons redistribute — and diffuse — the energy among themselves. Saudi Arabia opens top-notch laser lab 2015-02-16T05:00:00Z The work confirms that vibrational bonds—fleeting though they may be—should be added to the list of known chemical bonds. Chemists Confirm the Existence of New Type of Bond 2015-01-28T05:00:00Z The dominant group of organisms they found there, archaea, survived and grew by consuming the energy found in the chemical bonds of ammonium. Researchers Discover Life Beneath Antarctica 2014-08-20T04:00:00Z The next version, beefed up with stronger chemical bonds, stayed together a little too well, forming a flat crepe that didn’t have any of the fluffiness of an egg. Coming Soon to a Walmart Near You: The Eggless Egg 2014-08-18T04:00:00Z “If we could just make one chemical bond at a time, in isolation, chemistry would be trivial,” he says. Organic synthesis: The robo-chemist 2014-08-05T04:00:00Z Chemical energy is another form of potential energy stored in molecular chemical bonds. Fact or Fiction?: Energy Can Neither Be Created Nor Destroyed 2014-08-05T04:00:00Z Similarly, alter the electromagnetic force, and the chemical bonds between atoms would be too weak or too strong to build the diversity of molecular structures that allows such incredible complexity in the cosmos. Is Earth’s Life Unique in the Universe? 2014-08-04T04:00:00Z Intrinsic systems use the reversible nature of certain chemical bonds to incorporate healing properties directly into the material. Self-healing plastic inspired by blood 2014-05-09T07:26:19Z “When magma cools quickly, it creates very small crystals. These ones interlocked, and chemical bonds developed between them,” says Martin Gillespie, a geologist at the British Geological Survey. From Scottish Magma to Sochi Ice: The Geologic History of Curling Stones 2014-02-08T17:00:00Z Physicists have been studying black phosphorus — a layered material held together by weak chemical bonds — since the 1960s. Phosphorene excites materials scientists 2014-02-05T18:21:02.448Z Good vibrations: Researchers tune the chemical bonds of buckyballs. Physics Week in Review: January 25, 2014 2014-01-25T05:52:03Z This technique captures chemical bond breaking and bond making in real time, providing detailed mechanistic information about the progress of a chemical reaction. Q&A: A man of many dimensions 2013-10-16T17:21:35.633Z The last big question in chemistry was 'what is the nature of the chemical bond?' — and that was answered almost 100 years ago with the advent of quantum mechanics. Q&A: A lateral thinker 2013-10-16T17:21:26.370Z A unique insight of the trio's work was to use computer simulations to combine quantum mechanics, which explains the making and breaking of chemical bonds, with classical Newtonian mechanics, which captures the movement of proteins. Scientists who took chemistry into cyberspace win Nobel Prize 2013-10-09T19:21:16Z Carbyne is a chain of carbon atoms held together by double or alternating single and triple chemical bonds. Material could be strongest yet 2013-10-10T11:52:19Z They discovered that charged particles are stabilized by radicals — reactive molecules with spare, unbound electrons that form when chemical bonds are broken on a surface. Vitamin E and Other Antioxidants Dispel Static Electricity 2013-09-20T15:45:03.497Z Does it mean the energy required to break all the chemical bonds in a substance? Excerpts From The Mad Scientist s Handbook: So You're Ready to Vaporize a Human 2013-09-12T17:45:14.177Z A growing number of cognitive scientists now believe that this cocktail-shaker approach could improve students’ comprehension of a wide array of scientific concepts, whether chemical bonds, parallel evolution, the properties of elementary particles or pre-algebra. Cognitive Science Meets Pre-Algebra 2013-09-02T19:22:05Z He sends his pieces of acrylic through the accelerator’s electron beam, which is designed to break chemical bonds in plastics. Fermilab Physicist Makes "Frozen Lightning" Art with Accelerators 2013-07-23T23:15:00.603Z Photo by Kathleen Raven The holy grail of energy storage may lie in chemical bonds, but a process for making this happen remains unknown. Energy storage, rare metals and the next ice age 2013-07-04T18:15:02.430Z The theory of bonding provided tantalizing explanations, but it was crystallography that allowed us to confirm the common provenance of molecules and the true nature of the chemical bond. Lindau 2013: Chemistry and diversity 2013-06-21T14:45:17.900Z Linus Pauling is one of these heroes, and I admire his contributions to the nature of the chemical bond and elucidation of its structure as well as his activism against war and nuclear weapons tests. 30 under 30: Designing New Ways to Stop Tumors 2013-06-16T17:15:00.313Z It noted that “in order to understand the nature of chemical bonds, the function of molecules in biological contexts, and the mechanism and dynamics of reactions, knowledge of the exact molecular structure is absolutely necessary.” Jerome Karle, 94, Dies; Nobelist for Crystallography 2013-06-15T03:09:10Z However, it is not the forces of energy trapped in chemical bonds or even the awesome power of the atom that we are now beginning to unleash, but human potential itself. Why 140 Characters Are Better Than A Flying Car 2013-05-11T12:29:26Z The process of marrying the screen to the tablet using different forms of chemical bonds prevents condensation, delivers cleaner text, improves contrast, and reduces glare and light reflectivity making the tablet easier to read outdoors. Why You Want The Microsoft Surface Pro (And Why You Don't) 2013-04-05T13:50:33Z The easiest representation would be the tactile models built and produced by chemists to aid with their visualization and analysis of various chemical bonds and isomers in stereochemistry. The Science and Art of Diagramming: Culturing Life and Chemical Sciences, Part II 2013-04-05T12:45:00.527Z When infrared light is transmitted through or reflected from a given sample, certain wavelengths are absorbed more than others by the vibrating chemical bonds. Organic versus Conventional: A Scanner May Say Which Is Healthier 2013-03-01T13:15:00.217Z Fiber-reactive dyes form permanent covalent chemical bonds with cellulose, making this dyeing process a relatively permanent one. Staining Science: Make the Boldest, Brightest Dye! 2013-02-21T15:15:00.307Z And then there are the schemes that store energy directly in chemical bonds, like splitting water to sequester hydrogen, or making more familiar fuels such as petrol. Petrol from air revisited: The energy storage debate 2012-11-01T14:40:17Z When asked what he would use Titan for, Nichols said he thought there was “fascinating” research to be done in chemical physics, specifically simulating the breaking of chemical bonds. Oak Ridge and NVIDIA unveil Titan supercomputer 2012-10-29T07:01:00Z The enzyme bonds to the substrate with a weaker chemical bond, a hydrogen bond or hydrophobic bond, for example. Enzymes: the little molecules that bake bread 2012-09-28T13:45:00.217Z Chemically, antibiotics are much more complex than anti-cancer or anti-viral drugs, looking more like a spider's web with their intricate patterns of chemical bonds. Caves key to fighting superbugs 2012-09-09T23:51:22Z Each polymer forms networks using different types of chemical bond: alginate molecules are linked together by ionic bonds, and polyacrylamide molecules by stronger covalent bonds. Super-Stretchy Hydrogel Can Take a Hit 2012-09-06T15:15:00.227Z These have allowed researchers to examine fast processes such as the making and breaking of chemical bonds, the study of which earned Ahmed Zewail . Team clocks shortest laser pulse 2012-09-06T09:16:34Z But the shock of any impact — a hard fall, or incoming bullet — will cause those chemical bonds to strengthen so the molecules lock into place and the fabric becomes instantly rigid. Walking on... Custard? Fun with Non-Newtonian Fluids 2012-09-05T20:45:12.803Z Once retrieved, the barnacles will be kept in an aquarium, and the researchers will examine gene expression in the animals and chemical bonds in the adhesive. Getting a Grip on the Goose Barnacle 2012-07-31T14:45:05.853Z The enzymes involved in these pathways often perform a spectacular, elegant dance in which multiple chemical bonds are formed with exquisite timing and selectivity. Gene duplication frees up enzymes for molecular promiscuity 2012-07-28T11:45:06.120Z That, in turn, may render chemical bonds shorter and stronger, making molecules trapped within such fields as much as 25% smaller, scientists estimate. ScienceShot: Unusual Molecules Form Near White Dwarfs 2012-07-19T19:05:00Z The way the hydrogen atoms fit themselves into the interface changes the nature of the chemical bonds between the two layers. 'Baked' graphene makes transistor 2012-07-18T07:26:31Z That timescale is even quicker than the making and breaking of chemical bonds. Physicists Invent First Tabletop X-Ray Source 2012-06-08T20:45:03.767Z The chemical bonds link the keratin molecules are what give a hair strand its strength and flexibility as well as its predictable response to humidity. Hairy Science: Measuring Humidity with a Hair Hygrometer 2012-04-19T14:15:00.237Z "It will now be possible to investigate at the single-molecule level how charge is redistributed when individual chemical bonds are formed between atoms and molecules on surfaces," said lead author of the research Fabian Mohn. Electric image of single molecule 2012-02-26T20:19:54Z The high-pressure water breaks chemical bonds within the lobsters' biological cells. Pressure Prepares Lobsters for Long-Distance Delivery 2011-12-07T16:02:00Z When you heated the paper, the heat caused some of the chemical bonds to break down, freeing the carbon. Invisible Ink Reveals Cool Chemistry 2011-11-03T14:15:03.317Z The nonionizing radiation given off by cellphones is too weak to break chemical bonds or damage DNA. Well: Piercing the Fog Around Cellphones and Cancer 2011-06-06T21:38:34Z Previous Posts The “breaking of the very strong chemical bond between two nitrogen atoms” is not so much biological but achieved by lightning strikes around the planet. Scientist at Work: Q. and A. on the Nitrogen Cycle 2011-05-26T15:57:10Z ANAHEIM, CALIFORNIA—Nearly all the energy we use on this planet starts out as sunlight that plants use to knit chemical bonds. Spinning the Sun's Rays Into Fuel 2011-03-28T20:30:02Z In other words, they flipped a switch, which allowed them to change the electrical conductivity of the silicon without making or breaking a single chemical bond within the surface. Flipping the World's Smallest Light Switch 2011-03-25T16:05:32Z With ChemJuice, just drag your finger across the touch screen to draw a chemical bond and tap the screen to delete an atom or bond or change its type. From iPhones to SciPhones 2011-03-18T13:45:11.480Z Dr. Herberman said skeptics about the risks of cellphones have focused on the fact that the type of radiation they emit is too weak to break chemical bonds and cannot plausibly be implicated in cancer. Well: Cellphone Use Tied to Changes in Brain Activity 2011-02-22T21:31:34Z Those telltale chemical bonds provide clues about how the material was preserved, says Cody. The Mystery of the Stone Scorpion 2011-02-10T22:11:53Z The heat and electric charges of the plasma break the chemical bonds in the waste, vaporising it. Waste disposal: Turning garbage into gas 2011-02-03T11:11:23Z Nevertheless, the ability to adjust the orientation of a single chemical bond within a molecule is a new benchmark in the precise mechanical control of matter. Flipping the World's Smallest Light Switch 2011-03-25T16:05:32Z As we have seen, Grotthus imagined that it was the electric forces which sheared the ions past each other and loosened the chemical bonds holding the opposite parts of each dissolved molecule together. Encyclopaedia Britannica, 11th Edition, Volume 9, Slice 2 "Ehud" to "Electroscope" 2011-01-29T03:00:23.777Z The squares are stacked in an offset manner, and each square forms chemical bonds with four squares in the layers above and four below. Not Your Parents' Carbon: A New Type of Crystalline Graphite 2011-01-27T18:45:00.330Z He also discovered DNA sequences for an enzyme the microbes deploy to break methane's chemical bonds. Bacteria devoured methane gas from gulf oil spill, scientists say 2011-01-06T19:20:00Z Phosphorus chains form the backbone of DNA and its chemical bonds, particularly in a molecule known as adenosine triphosphate, the principal means by which biological creatures store energy. With Arsenic-Eating Microbe, New Thinking on What Constitutes Life 2010-12-02T17:53:00Z The research is basic science, but Yoo says it shows it is possible to store mechanical energy into the chemical energy of a material with such strong chemical bonds. Researchers Use Super-High Pressures To Create Super Battery 2010-07-09T13:31:00Z It was a painstaking process, requiring researchers to add chemical bonds to stabilize the replica so that it wouldn't collapse and lose its shape. Advance in Quest for HIV Vaccine 2010-07-09T03:43:00Z A carotenoid molecule, for instance, is shaped like a barbell, a shape with a pattern of chemical bonds that absorbs everything except a yellow or orange color, which is what we then see. Dinosaur-era plants learned the value of scent and sensibility 2010-04-13T04:00:00Z X-rays are in the category of "ionizing radiation" -- that is, waves with enough energy to tear the electrons off atoms and break chemical bonds. 2010-02-02T05:00:00Z The chemical bonds of this phosphorus in the molecules of nucleic substances were determined in later work. History of Phosphorus The nature of the chemical bond, and the structure of molecules and crystals. U.S. Copyright Renewals, 1967 July - December This disrupts the chemical bonds for critically important cell structures like the cytoplasm, which carries the cell's genetic blueprints, and also produces chemical constituents which can cause as much damage as the original ionizing radiation. Worldwide Effects of Nuclear War: Some Perspectives |
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