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Strongest material

Carbon's New Champion

Rice University theorists calculate atom-thick carbyne chains may be strongest material ever.

Image: Rice University researchers have determined from first-principle calculations that carbyne would be the strongest material yet discovered.

The carbon-atom chains would be difficult to make but would be twice as strong as two-dimensional graphene sheets.

[Credit: Vasilii Artyukhov, Rice University].


Biomass catalytic tandem reaction

A Tandem for Biomass

Catalytic tandem reaction for the conversion of lignin and bio-oil by hydroxylation of phenols to form arenes.

Image: The conversion of lignin into low-boiling-point arenes instead of high-boiling-point phenols could greatly facilitate conventional refinery processes. A new procedure for the depolymerization of lignin and simultaneous conversion phenols into arenes is described.

[Source: Angewandte Chemie]


Reactant and Product Molecules

Direct Imaging of Covalent Bond Structure

Atom by atom, bond by bond, a chemical reaction caught in the act - Berkeley Lab scientists make the first-ever high-resolution images of a molecule as it breaks and reforms chemical bonds.

Image: The original reactant molecule, resting on a flat silver surface, is imaged both before and after the reaction, which occurs when the temperature exceeds 90 degrees Celsius. The two most common final products of the reaction are shown [Credit: Lawrence Berkeley National Laboratory and University of California at Berkeley].


Graphene/Boron for Batteries

Add Boron for Better Batteries

Rice University theorists say graphene-boron mix shows promise for lithium-ion batteries.

Image: A theory developed at Rice University determined that a graphene/boron compound would excel as an ultrathin anode for lithium-ion batteries. The compound would store far more energy than graphite electrodes used in current batteries [Credit: Vasilii Artyukhov/Rice University].


Integrated Artificial Photosynthesis Nanosystem

Nano-forest for Solar Water-splitting

Berkeley Lab researchers report first fully integrated artificial photosynthesis nanosystem.

Image: This is a schematic of the nanoscale tree-like heterostructures used for solar-driven water splitting in which TiO2 nanowires are grown on the upper half of a Si nanowire, and the two semiconductors absorb different regions of the solar spectrum. Insets display photoexcited electron-hole pairs separated at the semiconductor-electrolyte interface to carry out water splitting with the help of co-catalysts [Credit: Peidong Yang group/Berkeley Lab and UC Berkeley].


Beautiful Nano Flowers

Beautiful Nano-Flowers

Elaborate nanostructures blossom from a chemical reaction perfected at Harvard.

Image: These false-color SEM images reveal microscopic flower structures created by manipulating a chemical gradient to control crystalline self-assembly.

[Credit: Wim L. Noorduin, Harvard University].


Astatine

First Ionization Potential of Astatine

Scientists uncover the fundamental property of astatine, the rarest atom on Earth.

Image: An international team of scientists, including a University of York researcher, has carried out ground-breaking experiments to investigate the atomic structure of astatine (Z=85), the rarest naturally occurring element on Earth.

The element is of significant interest as its decay properties make it an ideal short-range radiation source for targeted alpha therapy in cancer treatment.


Hill Cap Cloud Thuringia 2010

Sulfate aerosols cool climate less than assumed

Life span of cloud-forming sulfate particles in the air is shorter than assumed due to a sulfur dioxide oxidation pathway which has been neglected in climate models so far.

Image: Measurement Station Schmücke. HCCT 2010 (Hill Cap Cloud Thuringia 2010) - A ground-based integrated study of chemical-aerosol-cloud interactions at the Schmücke Mountain in the Thuringian Forest in September/October 2010 [Credit: Dr. Stephan Mertes, TROPOS].


Gold/titanium dioxide catalyst in action

Mysterious Catalyst Explained

How tiny gold particles aid the production of plastic components.

Image: At the interface between a gold particle and the titanium dioxide surface, an oxygen molecule is activated by a charge transfer and becomes catalytically active. Thus, methanol can be efficiently and selectively oxidized to formaldehyde; water is produced as well.

[Credit: M. Farnesi Camellone, D. Marx]


Chemical memory of water

The Chemical History of the Oceans

The chemical memory of seawater: scientists examine the biomolecules dissolved in the ocean and read them like a history book of the sea.

Image: The subsequent analysis in the mass spectrometer generates a chemical fingerprint which indicates the origin of the organic substances.

[Credit: Yves Nowak, Alfred Wegener Institute].


Iridium-Catalyzed Hydrosilylation

Iridium Catalyzed Carbon Fixation

Made out of thin air - fixation of carbon dioxide through iridium catalyzed hydrosilylation.

Image: An air- and moisture-stable iridium(III) catalyst effectively promotes the hydrosilylation of carbon dioxide [Credit: Angewandte Chemie International Edition].


Decay of element 113

New Result in the Production of Ununtrium

Search for element 113 concluded at last - After many years of painstaking work, Japanese researchers prove third time's a charm.

Image: The observed decay chain of element 113 (Ununtrium). A chain of six consecutive alpha decays, produced in experiments at the RIKEN Radioisotope Beam Factory (RIBF), conclusively identifies the element through connections to well-known daughter nuclides.

[Credit: RIKEN]


Mercury detection

Mercury Detected with Nanotechnology

Inexpensive, super-sensitive device detects even low levels of toxic metals in water, fish.

Image: Commercial strip of glass covered with a film of 'hairy' nanoparticles, a kind of a 'nano-velcro,' that can be dipped into water to measure mercury levels.

[Credit: The Grzybowski Group, Northwestern University]


Azo-Propofol

Azo-Propofols

Shine and Rise - Light-activated Reversal of Anesthesia.

Azobenzene derivatives of propofol increase GABA-induced currents in the dark form and loose this property upon light exposure and thus function as photochromic potentiators. The coumpound can be employed as a light-dependent general anesthetic in translucent tadpoles.


Artemisinin

A Short, Low-cost Synthesis of Artemisinin

IU chemist develops new synthesis of most useful, yet expensive, antimalarial drug.

Key to the success of the strategy was the development of mild, complexity-building reaction cascades that allowed the use of readily available, affordable cyclohexenone as the key starting material.


Amphiphilic carbon dots

Fluorescent Carbon Dots

Luminescent ink from eggs: C-dots can be made by plasma pyrolysis and used as printer ink.

Image: How do you like your eggs? Amphiphilic carbon dots (CDs) with intense blue fluorescence have been produced from chicken eggs by treatment with plasma. They are used as effective 'fluorescent carbon inks' for multicolor luminescent inkjet and silk-screen printing.

[Credit: Angewandte Chemie]


Enzymatic etching

Enzymatic Etching

Enzymes dig channels - enzymatic etching used to build nano- and microscale surface topologies.

Image: [credit Angewandte Chemie]


Highest surface area material

New World Record Set for Highest Surface Area

Northwestern University researchers have broken a world record by creating two new synthetic materials with the greatest amount of surface areas reported to date.

Image: Researchers have synthesized, characterized, and computationally simulated the behavior of two new metal-organic framework (MOF) materials displaying the highest experimental Brunauer-Emmett-Teller (BET) surface areas of any porous materials reported to date (7000 m2/g).

[Credit: JACS, ACS]


Optimized results from photoluminescent probes

Optimizing the Sensitivity of Photoluminescent Probes

Rice University researchers fine-tune time-resolved spectroscopy for the study of molecular-scale fluorescent targets.

Image: Researchers at Rice are working to optimize results from photoluminescent probes essential to the study of microscopic structures like cells, proteins and DNA.

The technique doubled the efficiency of a hairpin-shaped probe called a molecular beacon (at left) to find a specific DNA sequence by maximizing the amount of signal pulled from the background noise.

[Credit: Marti Group/Rice University]


Dynamic Force Spectroscopy

The Way in Which Molecular Bonds Form and Rupture

Forcing the molecular bond issue: New and improved model of molecular bonding from researchers at Berkeley Lab's molecular foundry.

Image: Under dynamic force spectroscopy, the bonds of a molecular system are subjected to controlled stretching until the bonds break.

The new model enables researchers to predict the 'binding free energy' of a given molecular system, which is key to predicting how that molecule will interact with other molecules.

[Image courtesy of Jim DeYoreo, Berkeley Lab].


Supernova

Stellar Nucleosynthesis of Silver in Supernovae

Heidelberg scientist shows that silver and gold materialised in different stellar explosions.

Image: The illustration is an artist’s impression of the first moments of an explosion before the star is completely torn apart.

[Source: European Southern Observatory/ESO]


Methane producing fungus

Methane Source Discovered in the Underbrush

Max Planck Institute for Chemistry: Greenhouse gas is also released by fungi.

Image:

Methane producers in the underbrush - New research shows that fungi can also produce methane.

[Credit Katharina Lenhart]


Water-Splitting Catalysts

A Way to Improved Water-splitting Catalysts

Caltech chemists identify the molecular mechanism by which such catalysts work.

Image:

Harry Gray's group at Caltech added a set of ligands to cobalt, slowing the reaction so that they could observe a key intermediate and then determine the chemical mechanism.

[Credit: Caltech/Marinescu et al.]


Two-step procedure to detect blood cyanide

Fast Detection of Blood Cyanide

Rapid response in cases of smoke poisoning by a two-step procedure to detect blood cyanide.

Image: A chemosensor added to the blood sample detects cyanides [Credit: UZH].


Graphene Illustration

Mechanisms of Graphene Growth

Every atom counts in graphene formation - Rice University lab's nanoreactor theory could advance quality of material's growth.

Image: Rice University researchers have come up with a set of calculations to predict how graphene grows in the process known as chemical vapor deposition. The graph set against an illustration of graphene growing on a nickel catalyst shows the initial energy barrier a carbon atom must overcome to join the bloom; subsequent atoms face an ever-smaller energy barrier until the process begins again for the next line [Credit: Vasilii Artyukhov/Rice University].


More CO2 leads to less clouds

More Carbon Dioxide Leads to Less Clouds

A new feedback mechanism operating between vegetation and cloud formation could enhance the climate change.

Image: The increase in carbon dioxide in the atmosphere causes an evaporation decrease of plants. As a result fewer cumulus clouds form, more sunlight reaches the ground - the climate change intensifies.

[Picture: Bart van Stratum]


Surface sensitive spectroscopy

Anchored proteins

RUB-Biophysicists use surface-sensitive spectroscopy to analyse the interaction between proteins and pharmaceuticals.

Image: New Bochumer Combination Method - Infrared spectra provide information about structural changes in proteins.

To study proteins that are activated through ligand-binding, the Bochumer researchers anchored the molecules to a lipid bilayer (gray) via a His-Tag.

[Credit: Philipp Pinkerneil und J. Gueldenhaupt]




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More News (open access):


That caffeine in your drink - is it really 'natural?'

That caffeine in your tea, energy drink or other beverage - is it really natural? Scientists are reporting successful use for the first time of a simpler and faster method for answering that question. Their report appears in the American Chemical Society (ACS) journal Analytical Chemistry.

Maik A. Jochmann, Ph.D., and colleagues point to the growing consumer preference for foods and beverages that contain only natural ingredients. Coffee, tea, colas, energy drinks and other caffeine-containing drinks are the most popular beverages in the world. Food regulatory agencies require that caffeine be listed on package labels, but do not require an indication of whether the caffeine is from natural or synthetic sources. The scientists set out to develop a faster, simpler method for categorizing caffeine’s origins.

In the study, they describe use of a technique called stable-isotope analysis to differentiate between natural and synthetic caffeine. The test makes use of differences in the kinds of carbon isotopes – slight variations of the same element – found in caffeine made by plants and caffeine made in labs with petroleum-derived molecular building blocks. Their analysis, which takes as little as 15 minutes, found four products that contained synthetic caffeine, despite a “natural” label.

The authors acknowledge funding from the German Federal Ministry of Economics and Technology and the German Research Foundation.

Analytical Chemistry: "Caffeine in Your Drink: Natural or Synthetic?". Anal. Chem., 2012, 84 (6), pp 2805–2810; DOI: 10.1021/ac203197d.


Pig stomach mucins are effective as anti-viral agents for consumer products

Scientists are reporting that the mucus lining the stomachs of pigs could be a long-sought, abundant source of “mucins” being considered for use as broad-spectrum anti-viral agents to supplement baby formula and for use in personal hygiene and other consumer products to protect against a range of viral infections. Their study appears in ACS’ journal Biomacromolecules.

In the report, Katharina Ribbeck and colleagues point out that mucus, which coats the inside of the nose, mouth and vagina, is the immune system’s first line of defense. The slimy secretion traps disease-causing microbes, ranging from influenza virus to HIV (which causes AIDS) before they can cause infection. That has led to consideration of mucin, the main component of mucus, for use as an anti-viral agent in a variety of products. However, existing sources of mucins, such as breast milk, cannot provide industrial-sized quantities. Large amounts of mucus exist in the lining of pigs’ stomachs, and the authors set out to determine if pig mucus - already used as a component of artificial saliva to treat patients with “dry mouth,” or xerostomia - has the same anti-viral activity.

They found that pig mucus is effective at blocking a range of viruses, from strains of influenza to the human papilloma virus, which is associated with cervical and oral cancer. They report that pig mucins could be added to toothpastes, mouthwashes, wound ointments and genital lubricants to protect against viral infections. “We envision porcine gastric mucins to be promising antiviral components for future biomedical applications,” the report says.

The authors acknowledge the National Institutes of Health and the German Academic Exchange Service (DAAD).

Biomacromolecules: "Mucin Biopolymers as Broad-Spectrum Antiviral Agents". 2012, DOI 10.1021/bm3001292.




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Chemistry

Chemistry

DNA-templated synthesis

DNA-Templated Synthesis on Solid Support

Direction Selection: new method for template-directed DNA synthesis in the 3' and 5' directions.

Image: Controlled, stepwise chain extension was demonstrated both in the direction favored by nature (3'-extension) and in the direction typical for conventional DNA synthesizers (5') [Credit: Angewandte Chemie].


Fenton Reaction

Fenton Reaction Mystery Solved

Ames Laboratory scientists crack long-standing chemistry mystery.

Image: Scientists have long debated whether it was a hydroxyl (OH) radical or a form of iron known as the ferryl ion, [Fe(IV)O]2+, that functioned as the reaction intermediate for the Fenton reaction, with data to support both theories [Credit: Chemical Science.

[DOI 10.1039/C2SC20099F]


Fluorescent photoswitchable system

A New Fluorescent Photoswitchable System

Designing tiny molecules that glow in water to shed light on biological processes: University of Miami researchers are creating fluorescent molecules that can be turned on and off in aqueous environments to visualize activity within cells [Image credit: Francisco Raymo / University of Miami].


UTPtNWs

Synthesis of Ultrathin Superlong Platinum Nanowires

First high electrocatalytic active ultrathin platinum nanowires with aspect ratio of at least 104 become a reality.

[Image credit: Faming Gao; JACS]


Dual role for carbon dioxide

Dual Role for Carbon Dioxide

Continuous hydrogenation of carbon dioxide to pure formic acid in supercritical CO2.

Scheme: Pure formic acid can be obtained continuously by hydrogenation of carbon dioxide in a single processing unit.

[Credit: Angewandte Chemie]




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Physics

Physics

Heaviest elements

Superheavy Elements: Stabilizing Shell Effects Directly Measured

Results will help to pin down the 'Island of Stability'.

Image: Chart of nuclides in the region of the heaviest elements.

[Credit: Courtesy of Science/AAAS]


Two-Electron Model

The 'N-representability Problem' Solved

New method knocks out stubborn electron problem: A newly published article in Physical Review Letters eliminates one of the top unsolved theoretical problems in chemical physics as ranked by the National Research Council in 1995.

Illustration of the two-electron model:

David Mazziotti, a professor in chemistry at the University of Chicago, has solved a longstanding problem in quantum theory: how to compute the energies and properties of any atom or molecule in terms of just two of its electrons.

[Credit: Kasra Naftchi-Ardebili]


Metal-organic spin crossover molecule

A Metal-Organic Spin Crossover Molecule

By electricity, researchers switch the magnetic state and electric resistance of a single molecule on and off - Blueprint for novel, compact storage media.

Image: Using a scanning tunneling microscope tip, defined electricity pulses were applied to the molecule, which switches between different magnetic states.

[Credit: CFN/KIT]




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Biochemistry / Chemistry and Biology

Biochemistry

Mustard oils as chemical mace

Mustard Oils as Chemical Mace

A German-Danish team is now presenting new findings about mustard oils in plant science in Nature - with interesting prospects for agriculture.

Image: When caterpillars or other hungry insects feed on glucosinolate-containing plants like broccoli, the glucosinolates get in contact with the enzyme myrosinase, that releases mustard oils. These ward off the insects.

[Picture: Dietmar Geiger].


Activation of substrate water molecules

Some Key Secrets of Photosynthesis Unlocked

Research on the water oxidation reaction in plants and bacteria helps solve an important piece of the solar energy conversion puzzle; represents a major step toward a new generation of photovoltaics.

Image: Energy and Environmental Science - The structure and activation of substrate water molecules in the S2 state of photosystem II studied by hyperfine sublevel correlation spectroscopy [Credit: RPI].




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Chemistry and Medicine

Medicinal Chemistry

Strawberries as sunblock

Strawberry Extract as Sunblock

An experiment has shown that strawberry extract added to skin cell cultures acts as a protector against ultraviolet radiation as well as increasing its viability and reducing damage to DNA.

Image: The reported experiment shows that strawberry extract added to skin cell cultures acts as a protector against UVA rays.

[Credit: SINC]


Quinolone amide

With Quinolone Amides Against Tropical Parasites

There is an urgent need for better drugs to treat African sleeping sickness. Würzburg scientists have developed a very promising new agent, which is now to be further optimized.

Image: Chemical structure of the agent quinolone amide, which kills off the pathogens responsible for the African sleeping sickness [Credit: Georg Hiltensperger, Nicola Jones].


Metal-peptide complex

Metal-Peptide Complexes: A New Avenue to Better Medicines

German-American research team produces metal-peptide complexes.

Image: Via metal coordination, rhodium is bound between the two carbon rings.

[Credit: Florian Wieberneit, Raphael Stoll]




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Chemistry and Materials

Materials Chemistry

Bipyridine on gold surface

First Single-Molecule Measurement of Van Der Waals Interactions

Unraveling intricate interactions, 1 molecule at a time: In key step towards design of better organic electronic devices, Columbia engineering team makes first single-molecule measurement of Van Der Waals interactions at a metal-organic interface.

Image: This is a model structure illustrating the bonding of bipyridine to the rough gold surface through direct nitrogen-gold chemical bonding and indirect van der Waals bonding [Credit: Columbia Engineering].


Aerographite

Aerographite - The Lightest Material in the World

A network of porous carbon tubes that is three-dimensionally interwoven at nano and micro level - this is the lightest material in the world.

Image: An Aerographite in the making. It offers enormous potentials - e.g. for the production of batteries. Aerographite is water-repellent, jet-black (which is currently analysed) and electrically conductive.

[Credit: Kiel University]




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Chemistry and Nanotechnology

Nanochemistry

Photocatalytic Nanocrystal

Synthesis of Nanocrystals that Harvest Solar Energy

A new video protocol in Journal of Visualized Experiments focuses on the liquid phase synthesis of two nanocrystals that produce hydrogen gas or an electric charge when exposed to light.

Image: This is a schematic of the photocatalytic nanocrystal.

[Credit: Journal of Visualized Experiments]


Genetic Code for Gold Nanoparticle Morphologies

DNA Code Shapes Gold Nanoparticles

Genetic Code for Gold Nanoparticle Morphologies: DNA holds the genetic code for all sorts of biological molecules and traits.

Image: University of Illinois chemists found that DNA can shape gold nanoparticle growth similarly to the way it shapes protein synthesis, with different letters of the genetic code directing triangular gold nanoprisms to grow into gold circles, stars and hexagons.

[Credit: Zidong Wang and Yi Lu]


Antibacterial silver ions

Antibacterial Activity of Silver

Ions, not particles, make silver toxic to bacteria. Rice University researchers report too small a dose may enhance microbes' immunity.

Image: Silver ions delivered by nanoparticles to bacteria promote lysis, the process by which cells break down and ultimately die, which makes silver nanoparticles a superior and widely used antibacterial agent.

[Credit: Zongming Xiu/Rice University]


Marine biofouling

Bioinspired Nanoparticles against Marine Fouling

Vanadium pentoxide nanoparticles mimic natural enzymes and inhibit surface build-up of algae and bacteria.

Image: a) Biofouling at a boat hull; b) knotted wrack, Ascophyllum nodosum; c) Mode of action of bioinspired under water paints.

Like the natural enzyme vanadium bromoperoxidase vanadium pentoxid nanoparticles act as a catalyst for the formation of hypobromous acid from bromide ions (contained in sea water) and small amounts of hydrogen peroxide that are formed upon exposure to sun light.

[Source/Copyright: Tremel research group, JGU]




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Chemistry and Environment

Environmental Chemistry

N2O-reductase

Nitrous Oxide Decomposition Mechanism

How the N2O greenhouse gas is decomposed.

Image: The N2O-reductase enzyme possesses four reactive centers for the decomposition of nitrous oxide into elemental nitrogen.

[Source: BIOSS/ University of Freiburg]


Silver Cycle

New evidence for natural synthesis of silver nanoparticles.

The Shape of Sulfur

Sulfur Dioxide Emissions

Worldwide sulfur emissions rose between 2000-2005, after decade of decline. Shipping, China top emissions growth in new analysis of 150 years of emissions.

Image: Manmade sulfur dioxide emissions by country show a decline by the historically large emitters - Europe and the US - but increases in growing economies up to 2005.

[Credit: Smith et al., Atmos Chem Phys 2011].




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Geochemistry

Geohemistry

How salt in the rainforest becomes clouds

Formation of Aerosols in the Rainforest

Potassium salts from fungi and plants initiate the formation of aerosol particles upon which moisture from the air condenses.

Image - Plant salts in clouds over rainforests: organic compounds condensate at potassium salts out of plants and fungi, so that aerosol particles form. They act as condensation seeds for fog and cloud droplets. How and why plants emit nonvolatile anorganic salts is as of yet unknown.

[Credit: C. Poehlker, MPI for Chemistry]


Sugar found in space

Glycolaldehyde Found in a Solar-type Protostar

Building blocks of life found around young star.

Image: This is the first time sugar been found in space around such a star, and the discovery shows that the building blocks of life are in the right place, at the right time, to be included in planets forming around the star.

The astronomers used the Atacama Large Millimeter/submillimeter Array (ALMA) to detect the molecules.

[Credit: ESO/L. Calçada & NASA/JPL-Caltech/WISE Team]


Sulfate-respiring bacteria

Dolomite Formation

How does Dolomite form?

Scientists in Kiel show the influence of marine bacteria on mineral formation.

This picture shows the biofilm of a sulfate respiring bacteria species. Small white dots show Dolomite crystals.

Photo taken with a confocal laser microscope.

[Credit: ETH Zurich/Uni Zurich]









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