Current Chemistry News: Scientific Reports and Press Releases

Green Chemistry with Sunlight

Fri, 24 Jun 2011 10:46:25 GMT

Green Chemistry with Sunlight

Combining electrochemistry and photovoltaics to clean up oxidation reactions.

Image: �Electrochemistry can oxidize molecules with any oxidation potential, because the electrode voltage can be tuned or adjusted, or I can run the reaction in such a way that it adjusts itself. So I have tremendous versatility for doing things,� says Kevin Moeller. Moreover, the byproduct of electrochemical oxidation is hydrogen gas, so this too is a clean process. Bit electrochemistry can be only as green as the source of the electricity. The answer is to use the cleanest possible energy, solar energy captured by photovoltaic cells, to run electrochemical reactions.

[Credit: David Kilper/WUSTL]

A New Class of Superatoms

Fri, 24 Jun 2011 09:54:00 GMT

Researchers discover superatoms with magnetic shells.

A Remarkable Advance in NMR Spectroscopy

Thu, 19 May 2011 19:55:33 GMT

A Remarkable Advance in NMR Spectroscopy

Nuclear magnetic resonance with no magnets.

Image: Hydrogen molecules consist of two hydrogen atoms that share their electrons in a covalent bond. In an orthohydrogen molecule, both nuclei are spin up. In parahydrogen, one is spin up and the other spin down. The orthohydrogen molecule as a whole has spin one, but the parahydrogen molecule has spin zero.

[Credit: Lawrence Berkeley National Laboratory]

Cassyrane: A Hint of Blackcurrant

Thu, 19 May 2011 18:53:19 GMT

Olfactory properties and gas-phase structures of Cassyrane stereoisomers.

Sharpening the Nanofocus

Wed, 18 May 2011 10:52:19 GMT

Sharpening the Nanofocus

Berkeley Lab researchers use nanoantenna to enhance plasmonic sensing.

Image: This is a scanning electron microscopy image showing a palladium nanoparticle with a gold antenna to enhance plasmonic sensing.

[Image courtesy of Alivisatos group]

Photosynthesis or Photovoltaics?

Sun, 15 May 2011 13:14:02 GMT

Photosynthesis or Photovoltaics?

Which is more efficient at harvesting the sun's energy, plants or solar cells? This salient question and an answer are the subject of an article published in the May 13, 2011 issue of the journal Science.

Image: Although both photosynthesis and photovoltaics harvest energy from the sun, they operate in distinctly different ways producing different fuels. It is not a simple task to find common ground between the two in order to compare energy conversion efficiency [Credit: Bob Blankenship].

Silver Cycle

Thu, 12 May 2011 14:37:21 GMT

New evidence for natural synthesis of silver nanoparticles.

The First Sighting of Fluorine-14

Wed, 11 May 2011 12:05:46 GMT

The First Sighting of Fluorine-14

A recent discovery of an extremely exotic, short-lived nucleus called fluorine-14 in laboratory experiments may indicate that scientists are gaining a better grasp of the rules of strong interaction.

Image: This graph shows the flourine-14 supercomputer predictions (far-left) and experimental results (center). The striking similarities between these graphs indicate that researchers are gaining a better understanding of the precise laws that govern the strong force [Credit: James Vary].

Light-triggered Activation of Myosin

Wed, 11 May 2011 11:24:05 GMT

Light-triggered Activation of Myosin

Nano-motor with a light switch: light-triggered myosin allows real-time study of cells.

Image: The incorporation of a caging group onto the essential phosphoserine residue of myosin by protein semisynthesis enables light-triggered activation of the protein.

[Credit: Angewandte Chemie International Edition]

Direct Air Capture of Carbon Dioxide with Chemicals

Tue, 10 May 2011 17:17:49 GMT

The American Physical Society has released a new assessment - Direct Air Capture of CO₂ with Chemicals - to better inform the scientific community on the technical aspects of removing carbon dioxide from the atmosphere.

Infrared Nanospectroscopy With a Thermal Source

Tue, 10 May 2011 16:42:36 GMT

Infrared Nanospectroscopy With a Thermal Source

CIC nanoGUNE develops Nano-FTIR-nanoscale infrared spectroscopy with a thermal source.

Image: The tip is illuminated with the broadband infrared radiation from of a thermal source and the backscattered light is analyzed with a Fourier spectrometer, yielding local infrared spectra with a spatial resolution better than 100 nm. The displayed graph shows infrared spectra of differently processed oxides in an industrial semiconductor device.

[Copyright F. Huth, CIC nanoGUNE]

Road for Producing Nanoribbons of Graphane

Tue, 10 May 2011 16:11:58 GMT

Road for Producing Nanoribbons of Graphane

An international research team has discovered a new method to produce belts of graphene called nanoribbons.

Image: Reaction of single-walled carbon nanotubes (SWNTs) with hydrogen gas was studied in a temperature interval of 400-550 �C and at hydrogen pressure of 50 bar.

[Credit: The Swedish Research Council]

Polymer Films by Click Chemistry

Tue, 3 May 2011 09:55:41 GMT

Polymer Films by Click Chemistry

Signpost for chemical snaps: copper ions as morphogens for the formation of polymer films by click chemistry.

Image: A polymer film is obtained by the Cu(I)-catalyzed Sharpless click reaction between two polymers, bearing either azide or alkyne groups, both present simultaneously in a Cu(II) solution (see picture).

The Cu(I) morphogen is generated at an electrode by applying an adequate potential. This concept can be extended to supramolecular films formed by coordination complexes.

[Credit: Angewandte Chemie International Edition]

Metal-free Click Polymerization of Propiolates and Azides

Tue, 3 May 2011 09:37:15 GMT

Researchers have expanded the range of monomer pairs used in their established metal-free click polymerization of aroylacetylene-azides to propiolate-azides.

Ceria as Oxygen Storage

Thu, 28 Apr 2011 21:32:50 GMT

Ceria as Oxygen Storage

2D beats 3D: Ceria in platelet form stores more oxygen than nanocrystalline form.

Image: Small plate structure makes big difference: A facile synthetic method for high-quality ceria nanoplates enclosed by (100) facets involves the usage of a mineralizer. Compared to the 3D ceria nanomaterials prepared by combustion and hydrothermal treatment, the ceria nanoplates exhibit superior oxygen storage properties.

[Credit: Angewandte Chemie International Edition]

Lollipops with Side Effects

Wed, 27 Apr 2011 22:34:23 GMT

Lollipops with Side Effects

A plant's sugary offering betrays caterpillars to predatory ants.

Image: Freshly hatched Manduca sexta larva (tobacco hornworm) consuming trichomes of wild tobacco (Nicotiana attenuata).

[Credit: MPI Chemical Ecology: Ian Baldwin, Alexander Weinhold]

On the Way to Hydrogen Storage?

Thu, 21 Apr 2011 08:17:21 GMT

On the Way to Hydrogen Storage?

A magnesium hydride cluster as a model for a hydrogen storage material at the sub-nanometer level.

Image: The largest ligand-stabilized magnesium hydride cluster, containing 8 Mg²⁺ and 10H^- ions, is a model for the smallest sub-nanometer-sized hydrogen storage material.

[Credit: Angewandte Chemie]

Simulating Hydrocarbon Formation in the Deep Earth

Thu, 21 Apr 2011 07:48:39 GMT

Simulating Hydrocarbon Formation in the Deep Earth

A computer modeling study published in the journal Proceedings of the National Academy of Sciences shows that at deep Earth pressures and temperatures, longer hydrocarbons may be formed from the simplest one, the methane molecule.

Image: First-principles molecular dynamics simulation of liquid methane in contact with a hydrogen-terminated diamond surface at high temperature and pressure.

The spontaneous formation of longer hydrocarbons is readily found during these simulations.

[Credit: Eric Schwegler, Lawrence Livermore National Lab]

Temperature-Tunable Selective Methane Catalysis

Fri, 15 Apr 2011 19:51:19 GMT

Temperature-Tunable Selective Methane Catalysis

Scientists finely control methane combustion to get different products.

Image: This diagram shows how catalysts of two gold atoms can help convert methane into ethylene at room temperature (shown in red) and into formaldehyde at lower temperatures (shown in blue).

The research was conducted by scientists at the Georgia Institute of Technology and the University of Ulm. It appeared in the April 14, 2011, edition of The Journal of Physical Chemistry C.

[Credit: Uzi Landman]

Inside View of a Uranium Nanosphere

Fri, 15 Apr 2011 18:10:54 GMT

Inside View of a Uranium Nanosphere

Recipe for radioactive compounds aids nuclear waste and fuel storage pools studies.

Image: The diagrammatic image, viewed from upper left to bottom right, shows steps in the templated creation of radioactive compounds. In this case, the red spidery-looking shape is oxygen building a cage around tantalum (blue sphere) ; green sphere is potassium, pink is cesium. The yellow boxes are uranyl peroxide. Chemical attractions force the disparate parts to self-assemble. The background is a transmitted light-microscope image of crystals of the final product, U28.

[Credit: Sandia National Laboratories]

Antennal Transcriptome Characterized

Fri, 15 Apr 2011 17:41:38 GMT

Antennal Transcriptome Characterized

Molecular messages from the antennae: Scientists assemble genes involved in regulating olfaction in the antennae of a moth.

Image: With the help of its antennae this night-active tobacco hornworm (Manduca sexta) has been able to locate wild tobacco flowers by smell and is now enjoying the nectar.

[Credit: MPI for Chemical Ecology/Danny Kessler]

Occurrence of furan in coffee

Fri, 15 Apr 2011 17:27:53 GMT

Occurrence of furan in coffee

Coffee in capsules contains more furan than the rest.

Image: Coffee in capsules contains more furan than the rest, although the levels are still within safe health limits.

[Credit: SINC]

Hopping Protons

Fri, 15 Apr 2011 00:21:07 GMT

Hopping Protons

Dr. Burkhard Schmidt simulates proton transfer in amino acids and small peptides on MATHEON. Proton transfer plays a role in energy conversion within solar cells and fuel cells, for example, and applies to the energy flow in batteries. It is even relevant to the development of new drugs.

Image: Snapshot from ab Initio Molecular Dynamic Simulation.

[Credit: Dr. Burkhard Schmidt]

Uranium Chemistry

Tue, 12 Apr 2011 12:36:05 GMT

Uranium Chemistry

LANL researchers improve path to producing uranium compounds, candidates for advanced nuclear fuels. New method may also benefit superconductor R&D.

Image: This illustration shows the structures of UI₄(1,4-dioxane)₂ (left) and the UI₃(1,4-dioxane)_1.5 complexes.

The 1,4-dioxane derivatives of uranium iodides are easy to make and can be converted into a range of other compounds.

[Credit: Jaqueline Kiplinger, LANL]

Double-Stranded DNA Catenane

Tue, 12 Apr 2011 11:55:44 GMT

Double-Stranded DNA Catenane

The world's smallest wedding rings: 2 interlocking rings of DNA are only visible through the scanning force microscope.

Image: The world's smallest wedding rings are built up by two interlocked DNA-strands.

[Credit: Alexander Heckel]

New Bilyaer Nanocatalyst System for Tandem Catalysis

Tue, 12 Apr 2011 10:40:35 GMT

New Bilyaer Nanocatalyst System for Tandem Catalysis

Berkeley Lab researchers report tandem catalysis in nanocrystal interfaces: Could be a boon to green energy.

Image: In a unqiue new bilyaer nanocatalyst system, single layers of metal and metal oxide nanocubes are deposited to create two distinct metal-metal oxide interfaces that allow for multiple, sequential catalytic reactions to be carried out selectively and in tandem.

[Image courtesy of Yang group]

New Method to Identify Latent Fingerprints

Tue, 12 Apr 2011 10:04:12 GMT

New Method to Identify Latent Fingerprints

Caught red-handed: detection of latent fingerprints through release of fluorescein from a nanofiber mat.

Image: An electrospun nanofiber mat is used to identify latent fingerprints on various surfaces within 30 seconds and produce inkjet-printed patterns.

In contrast to classical approaches, the method is easy-to-operate, environmentally friendly, and has implications in other applied systems including chemical sensors, drug delivery, biological detection, and microreactors.

[Credit: Angewandte Chemie, DOI 10.1002/anie.201006537]

A New Test for Germs

Mon, 11 Apr 2011 17:59:39 GMT

Fluorescing DNAzymes detect metabolic products from bacteria.

New Database of Zeolite-like Materials

Tue, 5 Apr 2011 23:33:23 GMT

New Database of Zeolite-like Materials

Exploring the possibilities for zeolites: Rice University team creates database of 2.6 million varieties of molecular sieves.

Image:

Artist Kelly Harvey evoked images of the sea and a coral reef to hint at the diversity and quantity of structures in Rice University's new database of 2.6 million zeolite structures.

[Credit: Kelly Harvey]

Ruthenium Complex for Tumor Diagnostics

Tue, 5 Apr 2011 14:02:40 GMT

Ruthenium Complex for Tumor Diagnostics

Phosphorescent metal-organic coordination polymers for optical imaging.

Image: Phosphorescent nanoscale coordination polymers (NCPs) with unprecedentedly high dye loadings were coated with thin silica shells to tune the dye release kinetics.

Further functionalization of the NCP/silica particles with poly(ethylene glycol) (PEG) and PEG-anisamide enhanced their biocompatibility and targeting ability, allowing cancer-specific imaging of human lung cancer H460 cells.

[Credit: Angewandte Chemie International Edition]

Strontium-90 Sequestration by Biomineralization

Tue, 5 Apr 2011 12:33:34 GMT

Strontium-90 Sequestration by Biomineralization

Addressing the nuclear waste issue: pond alga could help scientists design effective method for cleaning up nuclear waste.

[Credit: ChemSusChem, Wiley, DOI 10.1002/cssc.201000448]

Amphiphilic Dendronized Homopolymers

Tue, 5 Apr 2011 12:21:27 GMT

A novel class of amphiphilic dendronized homopolymers has been reported by The Department of Polymer Materials, Shanghai University.

Polymerization in a Microreactor

Mon, 4 Apr 2011 12:39:51 GMT

Polymerization in a Microreactor

Small scale chemistry could lead to big improvements for biodegradable polymers.

Image: Typical NIST microreactor plate for studying enzyme catalyzed polymerization. The aluminum plate, topped with a transparent film, is approximately 40 millimeters by 90 mm. The channel, filled with plastic beads carrying the enzyme catalyst, is 2 mm wide and 1 deep.

[Credit: Kundu, NIST]

Alternating-Color Quantum Dots

Wed, 30 Mar 2011 12:02:15 GMT

Alternating-Color Quantum Dots

Twinkle, twinkle, quantum dot - new particles can change colors and tag molecules.

Image: Researchers at Ohio State University have invented fluorescent nano-particles that change color to tag molecules under the microscope. This series of photos shows a particle changing from red to green - and, at the 89-second mark, to yellow - over the course of two minutes.

[Image by Gang Ruan, courtesy of Ohio State University]

Hyperspectral Nanoscale Imaging

Wed, 30 Mar 2011 11:14:35 GMT

Hyperspectral Nanoscale Imaging

Next-generation chemical mapping on the nanoscale ...

[Image Credit: Nano Letters]

Epigenetic Reprogramming

Fri, 25 Mar 2011 14:17:42 GMT

Epigenetic Reprogramming

Saarbr�cker researchers show how parental genomes are reprogrammed at the start of life in mammals.

Image: Female and male-derived chromosomes of a fertilized egg of a mouse. The male-derived chromosomes appear red - their genom is already reprogrammated totally. The female-derived chromosomes (blue) are protected against the decoding process.

[Credit: Saarland University, Prof. Walter]

Catalytic Z-Selective Olefin Cross-Metathesis

Thu, 24 Mar 2011 18:19:31 GMT

Catalytic Z-Selective Olefin Cross-Metathesis

New method for preparation of high-energy carbon-carbon double bonds. BC and MIT researchers reveal power of new catalyst class and olefin metathesis process.

Image: The described catalyst controlled Z-selective cross-metathesis (CM) yields up to 98% Z-isomers.

[Credit: Nature]

Poly(propylene carbonate) Stereogradient

Tue, 22 Mar 2011 19:46:01 GMT

Poly(propylene carbonate) Stereogradient

Sorted building blocks: synthesis of stereogradient poly(propylene carbonate).

Image credit: Angewandte Chemie International Edition]

Crystal-Structure-Prediction of Sulfonimides

Tue, 22 Mar 2011 18:01:15 GMT

Crystal-Structure-Prediction of Sulfonimides

Tough crystal nut cracked: Correct prediction of all three known crystal structures of a sulfonimide.

Image: Past failures to predict the polymorphs of a sulfonimide using molecular mechanics have led to speculation that crystal-structure prediction may be of limited use owing to the kinetic nature of crystallization. An approach based on quantum mechanics now successfully predicts the three known polymorphs of this compound (molecule VI). Accurate lattice energy calculations are thus sufficient to predict the polymorphs of small organic molecules.

[Credit: Angewandte Chemie International Edition]

Primordial Soup Gets Spicier

Tue, 22 Mar 2011 17:44:32 GMT

Primordial Soup Gets Spicier

'Lost' samples from famous origin of life researcher could send the search for Earth's first life in a new direction.

Image: Preserved samples from a 1958 experiment done by "primordial soup" pioneer Stanley Miller contain amino acids created by the experiment. The samples had not undergone analysis until recently when Miller's former student Jeffrey Bada and colleagues discovered a wide range of amino acids.

[Credit: Scripps Institution of Oceanography, UC San Diego]

Synchrotron-based Chemical Imaging

Tue, 22 Mar 2011 15:28:52 GMT

Synchrotron-based Chemical Imaging

New imaging technique provides rapid, high-definition chemistry. Chemical images now much more detailed.

Image: IRENI-generated images (right) are 100 times less pixelated than in those from conventional infrared imaging (left). Using multiple beams from a synchrotron provided made the difference, providing enough light to obtain a detailed image of the sample. With this technique, the quality of the chemical images is now similar to that of optical microscopy.

[Credit: Carol Hirshmugl/Michael Naase]

About a New Vanadium Redox Flow Battery

Tue, 22 Mar 2011 12:25:03 GMT

About a New Vanadium Redox Flow Battery

Upgrading the vanadium redox battery: New electrolyte mix increases energy storage by 70 percent.

Image:

This artist's rendering of an upgraded vanadium redox battery shows how using both hydrochloric and sulfuric acids in the electrolyte significantly improves the battery's performance and could also improve the electric grid's reliability and help connect more wind turbines and solar panels to the grid.

[Credit: Pacific Northwest National Laboratory]

Neptunyl Interaction with Green Rust

Tue, 22 Mar 2011 12:06:02 GMT

Neptunyl Interaction with Green Rust

Green sludge can protect groundwater from radioactive contamination.

Image: University of Copenhagen chemists have shown that green rust is capable of capturing and containing almost any kind of pollution in soil due to its extreme chemical reactivity.

[Credit: Bo C. Christiansen/University of Copenhagen - NanoScience center]

On the Origin of An Enzyme

Tue, 22 Mar 2011 10:52:10 GMT

On the Origin of An Enzyme

Production of mustard oils: During the evolution of plants of the mustard family a leucine producing enzyme mutated into an enzyme that protects plants against herbivores.

Image: Plants of the mustard family, such as cabbage, produce glucosinolates that help to fend off herbivorous insects by reacting as part of 'mustard oil bombs'. Inserted into the photo is a three-dimensional model of the enzyme IPMS, which is involved in the formation not of glucosinolates, but of the amino acid leucine.

[Credit: MPI for Chemical Ecology/A. Schneider; enzyme model based on Koon, PNAS 101, 2004]

Chemically Selective Gas Sweetening

Tue, 22 Mar 2011 09:44:46 GMT

New method could improve economics of sweetening natural gas. ASSR could reduce amount of heat needed in purification process.

Nanocomposite for H Storage

Sun, 13 Mar 2011 21:28:27 GMT

Nanocomposite for H Storage

Berkeley Lab scientists achieve breakthrough in nanocomposite for high-capacity hydrogen storage.

Image: This schematic shows high-capacity magnesium nanocrystals encapsulated in a gas-barrier polymer matrix to create a new and revolutionary hydrogen storage composite material.

[Credit: Jeff Urban]

Fluorescent Chimeric Biomolecules

Thu, 10 Mar 2011 13:01:32 GMT

Fluorescent Chimeric Biomolecules

Synthetic biology: TUM researchers develop novel kind of fluorescent protein.

Image: JACS article - Biosynthesis of a fluorescent protein with extreme pseudo-Stokes shift by introducing a genetically encoded non-natural amino acid outside the fluorophore.

A novel kind of fluorescent protein relying on the intramolecular interplay between two different fluorophores, one of chemical origin and one of biological origin, was developed.

[Credit: A. Skerra / TUM]

Chemically Tuning of Enzymes

Thu, 10 Mar 2011 10:06:59 GMT

Chemically Tuning of Enzymes

Extra guest molecule in an enzyme's binding pocket enables methane oxidation.

Image: A new spin - The addition of chemically inert perfluoro carboxylic acids (green; see picture) to P450 enzymes results in dramatic activation of their catalytic activity as a result of the conversion of the Fe/heme from a low-spin to a high-spin state, and the reduction of the binding-pocket size.

Together these effects allow otherwise inert substrates such as propane and even methane to be oxidized.

[Credit: Angewandte Chemie International Edition]

Three-dimensional Chemical Patterns

Tue, 8 Mar 2011 11:39:23 GMT

Three-dimensional Chemical Patterns

Glowing spirals: chemical scaffolds guide living cells into precisely defined three-dimensional patterns.

Image: Falling into line - A method for the precise generation of durable 3D chemical patterns within stationary media was used to direct the chemotactic self-organization of living cells. A container with carefully positioned slits, through which a chemoattractant (yellow) can diffuse, controls the self-organization of Escherichia coli cells (green ellipsoids) expressing green fluorescent protein into a helical pattern (see fluorescence images).

[Credit: Angewandte Chemie]

Radon-220 Measurement

Tue, 8 Mar 2011 08:57:40 GMT

Accurate measurement of radioactive thoron possible at last.