Current Chemistry News: Scientific Reports and Press Releases

How Handedness Arises

Wed, 9 May 2012 00:35:05 GMT

How Handedness Arises

UCLA chemists solved a molecular mystery, and report the discovery in the journal Nature Communications.

Image: Achiral triangles form chiral super-structures.

Colored patches represent parallelogram outlines around pairs of triangles that have formed chiral super-structures.

Parallelograms having different 'handedness' and orientations are color-coded and superimposed over each other.

[Credit: Thomas G. Mason and Kun Zhao]

Ultrasmall Cadmium Selenide Nanocrystals Brighten the Future of Lighting

Wed, 9 May 2012 00:12:48 GMT

Ultrasmall Cadmium Selenide Nanocrystals Brighten the Future of Lighting

Vanderbilt researchers have boosted the efficiency of a novel source of white light called quantum dots more than tenfold, making them of potential interest for commercial applications.

Image: Enhanced and original white light quantum dots.

Pictured is a vial holding original white-light quantum dots on the left and a vial holding the enhanced quantum dots on the right.

[Credit: Rosenthal Lab]

Catalytic Production of Renewable Xylene

Tue, 1 May 2012 07:53:28 GMT

Catalytic Production of Renewable Xylene

Chemical engineers at UMass Amherst find high-yield method of making p-xylene from biomass.

Image: Reasearchers investigated a renewable route to p-xylene from biomass-derived dimethylfuran and ethylene with zeolite catalysts.

Cycloaddition of ethylene and 2,5-dimethylfuran and subsequent dehydration to p-xylene has been achieved with 75% selectivity using a H-Y zeolite and an aliphatic solvent at 300 �C.

[Credit: University of Massachusetts, Amherst]

A New Nanotube-based Chemoresistive Sensor for Ethylene

Mon, 30 Apr 2012 19:49:28 GMT

A New Nanotube-based Chemoresistive Sensor for Ethylene

Comparing apples and oranges: New sensor can accurately measure fruits' ripeness, helping prevent loss of produce from spoilage.

Image: The selective detection of ethylene gas using a carbon nanotube-based devices is described in the journal Angewandte Chemie.

[Credit: MIT]

A New Technique that will Transform Epigenetics Research

Thu, 26 Apr 2012 22:08:58 GMT

A New Technique that will Transform Epigenetics Research

Scientists at the University of Cambridge and the Babraham Institute have demonstrated a new technique that will transform epigenetics research: The quantitative sequencing of 5-methylcytosine and 5-hydroxymethylcytosine at single-base resolution.

Image: The centre of the diagram shows levels of 5mC and 5hmC chemical modifications along a chromosome (section of DNA). The cycle illustrates that after addition to DNA, 5mC (blue) can be converted to 5hmC (red) and then subsequently removed.

[Credit: Miguel Branco]

Custom Designed Protein Crystals

Thu, 26 Apr 2012 00:28:05 GMT

Custom Designed Protein Crystals

Protein design is technique that is increasingly valuable to a variety of fields, from biochemistry to therapeutics to materials engineering. University of Pennsylvania chemists have taken this kind of design a step further; using computational methods, they have created the first custom-designed protein crystal.

Image: Illustration of the researchers' target protein crystal.

[Credit: Christopher MacDermaid, University of Pennsylvania]

A Molecular Walker

Wed, 25 Apr 2012 23:52:31 GMT

A Molecular Walker

A small molecule moves independently along a track.

Image: A molecule is able to walk back and forth upon a five-foothold pentaethylenimine track without external intervention. The 1D random walk is highly processive (mean step number 530) and exchange takes place between adjacent amine groups in a stepwise fashion. The walker performs a simple task whilst walking: quenching of the fluorescence of an anthracene group sited at one end of the track.

[Credit: Angewandte Chemie International Edition]

Cement Hydration

Fri, 20 Apr 2012 11:51:09 GMT

Cement Hydration

The first seconds in a building�s life: X-ray diffraction studies of cement hydration on the millisecond scale.

Image: Highly dynamic hydration processes that occur during the first seconds of cement hydration were studied by time-resolved synchrotron X-ray diffraction.

Polycarboxylate ether additives were found to influence the formation of the initial crystalline hydration products on a molecular level.

[Credit: Angewandte Chemie International Edition]

The Chemical Composition of Caramel

Sat, 14 Apr 2012 18:18:51 GMT

The Chemical Composition of Caramel

Sticky stuff: Jacobs researchers reveal the sweet secret of caramel.

Image:

At least 4000 chemical components can be found in caramel.

[Cedit: iStockphoto]

Improved Mussel Adhesive

Sat, 14 Apr 2012 14:05:53 GMT

Improved Mussel Adhesive

Biocompatible, waterproof, self-healing, and reversible: A new adhesive for medical applications?

Image: Bioinspired underwater chemical bonding with the possibility of phototriggered debonding is reported. A four-arm star-poly(ethyleneglycol) end-functionalized by nitrodopamine was synthesized.

[Credit: Angewandte Chemie International Edition]

Microfluidic Electrochemical DNA Amplification

Sat, 14 Apr 2012 13:07:28 GMT

Microfluidic Electrochemical DNA Amplification

Everything flows in rapid diagnostic tests: A new amplification technique allows for the rapid, sensitive, and quantitative detection of pathogenic DNA.

Image: A microfluidic electrochemical loop-mediated isothermal amplification platform is reported for rapid, sensitive, and quantitative detection of pathogen genomic DNA at the point of care.

[Credit: Angewandte Chemie International Edition]

Processes at the Surface of Catalysts

Tue, 10 Apr 2012 20:27:09 GMT

Processes at the Surface of Catalysts

Using infrared spectroscopy, scientists detect that oxygen defects act as active centers.

Image: Defect concentration on rutile surfaces of both monocrystals and powder particles can be determined by infrared spectroscopy using carbon monoxide as a probe molecule [Graphics: Dr. M. Xu, RUB].

Monorhaphis chuni: A Living Climate Archive

Mon, 2 Apr 2012 20:22:56 GMT

Monorhaphis chuni: A Living Climate Archive

An 11,000 year-old deep-sea sponge provides a record of past environmental changes in the sea.

Image: Microscopic image of a glass sponge. The image shows a one millimeter cross section of the skeleton of Monorhaphis chuni. The lamellae grew inside outwards during the 11,000 years. The chemical elements incorporated during this period show that the water temperature in its environment changed significantly several times.

[Credit: Werner E. G. M�ller, University Medical Center Mainz]

In Vivo Study of the Selenium Metabolism

Tue, 27 Mar 2012 19:49:52 GMT

In Vivo Study of the Selenium Metabolism

Keeping track to selenium metabolism: Spanish and Danish researchers have developed a method for the in vivo study of the unknown metabolism of selenium, an essential element for living beings. The technique can help clarify whether or not it possesses the anti-tumour properties that have been attributed to it and yet have not been verified through clinical trials.

Imagey: The technique allows for infinitesimal amounts of selenium to be quantified in their different chemical forms.

[Credit: J. Giner et al.]

Efficient Fluorescent Labeling of the RNA

Tue, 20 Mar 2012 21:35:21 GMT

Efficient Fluorescent Labeling of the RNA

Scientists of the University of Innsbruck, Austria, tested a new chemical modification of RNA molecules successfully for the first time. The results of the close cooperation of two research groups of the Centre for Molecular Biosciences (CMBI) have been published in the journal ACS Chemical Biology.

Image: A fluorescent dye lightens up the modified RNA in the cell.

[Credit: University of Innsbruck]

Solvent-free Luminescent Organic Liquids

Fri, 16 Mar 2012 13:59:42 GMT

Solvent-free Luminescent Organic Liquids

Glowing white: researchers develop uncharged organic substances that are luminescent liquids at room temperature and require no solvent.

Image: Isolation of a π-core by covalently attached flexible hydrocarbon chains has been employed to synthesize blue-emitting oligo(p-phenylenevinylene) (OPV) liquids with tunable viscosity and optical properties.

[Credit: Angewandte Chemie]

A New Structure-Control Strategy to Tune and Optimize NP Catalysis

Mon, 12 Mar 2012 19:35:26 GMT

A New Structure-Control Strategy to Tune and Optimize NP Catalysis

Touch of gold improves nanoparticle fuel-cell reactions.

Image: Gold atoms create orderly places for iron and platinum atoms, then retreat to the periphery of the fuel cell, where they scrub carbon monoxide from fuel reactions. The tighter organization and cleaner reactions extend the cell's performance life.

[Credit: Sun Lab/Brown University]

N-omega-Amino Acids in Antarctic Meteorites

Fri, 9 Mar 2012 19:50:14 GMT

N-omega-Amino Acids in Antarctic Meteorites

Meteorites reveal another way to make life's components

Image: A meteorite is analyzed in the study at its collection site in Antarctica.

[Credit: Antarctic Search for Meteorites program, Case Western Reserve University]

Single Atoms as Catalysts in Hydrogen-Related Reactions

Thu, 8 Mar 2012 21:20:38 GMT

Single Atoms as Catalysts in Hydrogen-Related Reactions

A new strategy for selective heterogeneous hydrogenations.

Image: A team of researchers have discovered that individual atoms can catalyze industrially important chemical reactions such as the hydrogenation of acetylene, a development with potentially significant economic and environmental benefits. The team found that individual atoms of costly palladium (yellow peaks) when placed in the surface of copper metal help break apart hydrogen molecules (grey circles) into atoms, facilitating important chemical reactions. These single atom alloys save money because they use less precious metal than conventional catalysts. They also yield less chemical byproduct waste, so they are better for the environment.

[Image/Figure courtesy of Sykes Laboratory-Tufts University]

DnaK: A Key Player of Protein Folding

Thu, 8 Mar 2012 20:24:52 GMT

Max Planck scientists identify one of the key players of the folding process: the molecular chaperone DnaK.

Electrochemical Small-Angle Neutron Scattering

Thu, 8 Mar 2012 20:12:21 GMT

Electrochemical Small-Angle Neutron Scattering

2 for 1: Simultaneous size and electrochemical measurement of nanomaterials.

Image: Schematic of NIST's 'eSANS' cell. A highly porous, sponge-like carbon electrode maximizes surface area for electrochemical reactions while structural details like particle size and configuration are measured using neutron scattering (image at left).

[Credit: Prabhu/NIST]

A Star-Shaped with a Magnetic Core

Wed, 7 Mar 2012 09:41:42 GMT

A Star-Shaped Molecule with a Magnetic Core

PDMAEMA stars as 'premium vectors' for the life sciences: magnetic nanoparticles.

Image: Schematic presentation of the new magnetic vectors: PDMAEMA arms attached to a crystalline iron oxide core stretch in all directions. The nanoparticle thus assumes a star-shaped appearance.

The abbreviation PDMAEMA stands for poly(2-(dimethylamino)ethylmethacrylat).

[Credit: Department of Process Biotechnology, University of Bayreuth]

New Method for the Detection of Chiral Molecules

Tue, 6 Mar 2012 23:42:51 GMT

New Method for the Detection of Chiral Molecules

Image or Mirror Image? - Chiral recognition by femtosecond laser.

Image: A circular dichroism effect in the +/- 10 % regime on randomly oriented chiral molecules in the gas phase is demonstrated. The signal is derived from images of photoelectron angular distributions (see picture) produced by resonance-enhanced multiphoton ionization and allows the enantiomers to be distinguished. To date, this effect could only be generated with a synchrotron source. The new tabletop laser-based approach will make this approach for more accessible.

[Credit: Angewandte Chemie]

Actinide-Specific Decontaminating Agents

Tue, 6 Mar 2012 23:11:13 GMT

Actinide-Specific Decontaminating Agents

Responding to the radiation threat - Berkeley Lab researchers developing promising treatment for safely decontaminating humans exposed to radioactive actinides.

Image: This octadentate HOPO is a sequestering agent that can encapsulate actinides, such as this plutonium atom (gold), into tightly bound cage-like complexes for excretion out of the body.

[Image by Zosia Rostomian, Berkeley Lab]

Synthesizing Catalysts that are all Edge

Fri, 24 Feb 2012 15:47:15 GMT

Synthesizing Catalysts that are all Edge

Breakthrough in designing cheaper, more efficient catalysts for fuel cells.

Image:

Redesigned catalyst for producing hydrogen.

Molybdenite (top) is a popular catalyst, but reactions take place only at edge sites (circle) where a molybdenum-sulfur-sulfur triangle protrudes.

UC Berkeley/LBNL chemists have created molecules (bottom) with only an active site triangle that efficiently convert water to hydrogen.

[Credit: Christopher Chang and Jeffrey Long, UC Berkeley]

Tellurium Found in Space

Tue, 21 Feb 2012 19:52:27 GMT

Tellurium Found in Space

Tellurium detected for the first time in ancient stars.

Image: Ultra pure tellurium crystal.

Using near-ultraviolet spectra obtained with the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope,scientists detect neutral tellurium in three metal-poor stars.

[Credit: MIT]

Black Arsenic

Fri, 17 Feb 2012 14:05:36 GMT

Black Arsenic

Synthesis and identification of metastable compounds.

Image: All metastable and stable phases can be identified for the solid solution arsenic/phosphorus by a combination of quantum-chemical calculations and investigations of the phase formation. Reaction paths for phase formations and transitions in situ were also evaluated. The results show that orthorhombic black arsenic (o-As) is metastable in pure form and has only been previously obtained by stabilizing impurities.

[Credit: Angewandte Chemie]

Hyperstoichiometry

Fri, 17 Feb 2012 13:20:12 GMT

Hyperstoichiometry

Tiny silver particles trap mercury: Hyperstoichiometric reaction between mercury ions and silver nanoparticles.

Image: As the diameter of silver particles is decreased below a critical size of 32 nm, the molar ratio of aqueous Hg^II to Ag⁰ drastically increases beyond the conventional Hg/Ag ratio of 0.5:1, leading to hyperstoichiometry with a maximum ratio of 1.125:1. Therein, around 99 % of the initial silver is retained to rapidly form a solid amalgam with reduced mercury.

[Credit: Angewandte Chemie]

Sugars Found in the Gas Phase

Thu, 16 Feb 2012 23:52:58 GMT

Sugars Found in the Gas Phase

The quest for sugars involved in origin of life; team from University of the Basque Country manage to isolate a sugar in gas phase for first time in history.

Image: The search for sugars in interstellar space is hampered by a lack of spectroscopic information.

D-Ribose is now the first C₅ sugar observed in the gas phase using microwave spectroscopy. The rotational spectrum revealed six conformations of free ribose, adopting preferentially �-pyranose rings and higher-energy a-pyranose forms. No evidence of a-/�-furanoses or linear forms was found, unlike biological systems, where �-furanoses are found in RNA.

[Credit: Angewandte Chemie, DOI 10.1002/anie.201107973]

New molecule can tangle up DNA for more than 2 weeks

Tue, 14 Feb 2012 20:53:11 GMT

New molecule can tangle up DNA for more than 2 weeks

Molecule is important step along the path to someday creating drugs that can go after rogue DNA directly.

Image:

Snaking Through the Ladder - The image shows a model of the "threading tetra-intercalator" bound up in the double helix of a DNA sequence.

[Credit: Brent Iverson]

MoleculaRnetworks:

Tue, 14 Feb 2012 08:54:08 GMT

MoleculaRnetworks: A PageRank for Atoms

WSU chemist applies Google software to webs of the molecular world.

Image: work discusses scripts for processing molecular simulations data written using the software package R: A Language and Environment for Statistical Computing.

[Credit: Wiley Periodicals, Inc.]

A Molecular Carpet" Made of 2-Dimensional Polymers

Mon, 13 Feb 2012 20:02:53 GMT

A Molecular Carpet Made of 2-Dimensional Polymers

Startling results in synthetic chemistry presented in Nature Chemistry: ordered 2-dimensional polymers created for the first time.

Image:

The regular (periodic) structure of the two-dimensional polymer is shown in images taken with a transmission electron microscope (TEM).

Each bright spot corresponds to a monomer molecule.

[Credit: Empa/ETH Zurich]

Hydrogen from Acidic Water

Thu, 9 Feb 2012 23:22:41 GMT

Hydrogen from Acidic Water

Berkeley Lab researchers develop a potential low cost alternative to platinum for splitting water.

Image: Using a molybdenite complex and thePY5Me₂ ligand, Berkeley Lab researchers synthesized a molecule that mimics catalytically active triangular molybdenum disulfide edge-sites.

The result is an entire layer of catalytically active material.

Molybdenum atoms are shown as green, sulfur as yellow.

[Credit: Berkeley Lab]

A Carbon Dioxide Absorbing Zeolite

Thu, 9 Feb 2012 17:06:27 GMT

NIST provides octagonal window of opportunity for carbon capture.

Matryoshka Molecules

Tue, 7 Feb 2012 23:17:26 GMT

Matryoshka Molecules

A bronze matryoshka doll - The metal in the metal in the metal: New way to highly efficient catalysts and nanotubes with unusual symmetry.

Image: Just like in the Russian wooden toy, a hull of 12 copper atoms encases a single tin atom.

This hull is, in turn, enveloped by 20 further tin atoms.

With their large surfaces these structures can serve as highly efficient catalysts.

[Credit: TUM]

Macroporous Polystyrene

Tue, 7 Feb 2012 23:02:38 GMT

Macroporous Polystyrene

All foamed up: synthesis of macroporous polystyrene through polymerization of foamed emulsions.

Image: An ideal template for the production of macroporous polystyrene can be prepared from foamed oil-in-water emulsions containing styrene, water, glycerol, and sodium dodecylsulfate. After addition of a photoinitiator the mixture is polymerized with UV light and the foam structure of the precursor is transferred to the polymer. The resulting materials display densely packed cells with windows between adjacent pores (SEM image; scale bar: 250 �m).

[Credit: Angewandte Chemie]

Luminescent Nanocrystals

Thu, 2 Feb 2012 11:01:39 GMT

Luminescent Nanocrystals

Bright lights of purity: Berkeley Lab researchers discover why pure quantum dots and nanorods shine brighter.

Image: Ion exchange of semiconductor nanocrystals yielded materials with poor optoelectronic properties such as low photoluminescence quantum yields. The reason for the low quantum yields of these nanocrystals are impurities at the level of a few atoms per nanocrystal ...

[Credit: Berkeley Lab]

Toxic Amino Acids

Thu, 2 Feb 2012 10:05:02 GMT

Toxic Amino Acids

Deadly chinese mushrooms: Amino acids revealed as cause of deaths in Yunnan province.

Image: Two unusual and toxic amino acids, 2R-amino-4S-hydroxy-5-hexynoic acid and 2R-amino-5-hexynoic acid have been isolated from the fruiting bodies of the mushroom Trogia venenata.

[Credit: Angewandte Chemie]

Oxygen as Insulator, Semiconductor and Metal

Thu, 2 Feb 2012 09:47:19 GMT

Oxygen as Insulator, Semiconductor and Metal

Oxygen molecule survives to enormously high pressures - RUB researcher calculates stability thresholds and structures of solid oxygen.

Image - Structures of solid oxygen under high pressure:

At 1.9 TPa, oxygen polymerizes and assumes a square spiral-like structure, which is semi-conducting ,,,

[Figure: Jian Sun]

Jupiter's 'Trojans' on an Atomic Scale

Sat, 28 Jan 2012 09:26:08 GMT

Jupiter's 'Trojans' on an Atomic Scale

The planet Jupiter keeps asteroids on stable orbits - and in a similar way, electrons can be stabilized in their orbit around the atomic nucleus; calculations carried out at the Vienna University of Technology have now been verified in an experiment.

Image: The Bohr model assumes that the electron moves around the nucleus, much like a planet around its star.

[Credit: Vienna University of Technology]

Sulfur Chemistry of Exploding Stars

Fri, 20 Jan 2012 19:08:51 GMT

Sulfur Chemistry of Exploding Stars

Meteorite contains evidence of formation of sulfur molecules in the ejecta of a supernova explosion.

Image: Star dust from a supernova - the electron microscopic image shows a silicon carbide grain from the meteorite Murchison. The approximately one micrometer small grains originate from a supernova as an isotopic analysis has shown. Isotopes are forms of an element with different weights.

[Credit: Peter Hoppe, Max Planck Institute for Chemistry]

The Great Gas Hydrate Escape

Thu, 19 Jan 2012 00:23:16 GMT

The Great Gas Hydrate Escape

Computer simulations revealing how methane and hydrogen pack into gas hydrates could enlighten alternative fuel production and carbon dioxide storage industries.

Image: A computer simulation of methane, also known as natural gas, escaping from a methane hydrate. Many of these methane hydrate subunits combine to form a chunk of ice that burns, and this simulation shows how methane can get out without collapsing the entire structure ...

[Credit: Sotiris Xantheas, PNNL]

Amphotericin B - New Studies on the Mechanism of Action

Tue, 17 Jan 2012 19:38:08 GMT

Amphotericin B - New Studies on the Mechanism of Action

Powerful drug's surprising, simple method could lead to better treatments.

Image: This is a model of amphotericin, the most relied-upon drug for treating fungal infections, despite its toxicity.

[Credit: Martin Burke]

Continuous-Flow Synthesis of Artemisinin

Tue, 17 Jan 2012 15:03:57 GMT

Continuous-Flow Synthesis of Artemisinin

Anti-malaria drug synthesised with the help of oxygen and light.

Image: A continuous-flow process that converts dihydroartemisinic acid into artemisinin is shown to be an inexpensive and scalable process that can ensure a steady, affordable supply of artemisinin.

[Credit: Angewandte Chemie International Edition]

Electrodissolution of Platinum

Mon, 16 Jan 2012 13:56:05 GMT

Electrodissolution of Platinum

Recycling platinum by electrochemical dissolution in an ionic liquid.

Image: A noncorrosive, basic ionic liquid has been developed as a solvent system for the electrodissolution of platinum. The metal is dissolved at an ultrahigh rate, and the facile recovery of pure platinum and platinum alloys from the same solution is achieved without any additional treatment of the solution or exchange of the medium.

[Credit: Angewandte Chemie International Edition]

2-D Networks from Boron Acids

Tue, 10 Jan 2012 10:40:44 GMT

2-D Networks from Boron Acids

The art of molecular carpet-weaving: Synthesis of well-ordered COF monolayers.

Image: A scanning electron microscopy image with a superimposed molecular model.

Two different straightforward synthetic approaches are presented to fabricate long-range-ordered monolayers of a covalent organic framework (COF) on an inert, catalytically inactive graphite surface.

[Credit: TU Munich]

Flerovium and Livermorium

Sat, 3 Dec 2011 12:12:42 GMT

Flerovium and Livermorium

Livermore and Russian scientists propose new names for elements 114 and 116.

Image: The IUPAC recommended new proposed names for elements 114 and 116, the latest heavy elements to be added to the periodic table.

Scienists Make Graphene Suitable for Organic Chemistry

Tue, 29 Nov 2011 20:07:00 GMT

Scientists Make Graphene Suitable for Organic Chemistry

Graphene lights up with new possibilities: Rice researchers' two-step technique makes graphene suitable for organic chemistry.

Image: Making a superlattice with patterns of hydrogenated graphene is the first step in making the material suitable for organic chemistry. The process was developed in the Rice University lab of chemist James Tour.

[Credit: Tour Lab/Rice University]

Supercool Liquid Water

Mon, 28 Nov 2011 18:57:54 GMT

Supercool Liquid Water

Utah chemists: Water doesn't have to freeze until minus 55 Fahrenheit.

Image: The box here is full of liquid water, which is not shown (white). Supercooled liquid water starts to become 'intermediate ice' (green) on the way to freezing into ice (red) well below the 32 degrees F that people normally consider water's freezing point. University of Utah chemists calculated that supercold water finally must freeze at minus 55 F.

[Credit: University of Utah]

BN-Methylcyclopentane: A Liquid-based Hydrogen Storage Material

Tue, 22 Nov 2011 23:23:55 GMT

BN-Methylcyclopentane: A Liquid-based Hydrogen Storage Material

New material may boost efforts to convert gasoline infrastructure into one based on hydrogen.

Image: Stored hydrogen releases in the presence of iron chloride via a storage technology created in the University of Oregon lab of Shih-Yuan Liu.

[Courtesy of Shih-Yuan Liu]