Evolution has created in bees, butterflies, and beetles something optical engineers have been struggling to achieve for years — precisely organized biophotonic crystals that can be used to improve solar cells, fiber-optic cables, and even cosmetics and paints.
Think about your favorite toys as a child. Did they light up or make funny noises when you...
The secret desire of urban daydreamers staring out their office windows at the sad brick walls...
A new semiconductor compound is bringing fresh momentum to the field of spintronics, an emerging breed of computing device that may lead to smaller, faster, less power-hungry electronics. Created from a unique low-symmetry crystal structure, the compound is the first to build spintronic properties into a material that's stable at room temperature and easily tailored to a variety of applications.
Proteins are the building blocks of all living things, and they exist in virtually unlimited varieties, most of whose highly complex structures have not yet been determined. Those structures could be key to developing new drugs or to understanding basic biological processes. But figuring out the arrangement of atoms in these complicated, folded molecules usually requires getting them to form crystals large enough to be observed in detail.
Nature packs away carbon in chalk, shells and rocks made by marine organisms that crystallize calcium carbonate. Now, research suggests that the soft, organic scaffolds in which such crystals form guide crystallization by soaking up the calcium like an "ion sponge". Understanding the process better may help researchers develop advanced materials for energy and environmental uses, such as for removing carbon dioxide from the atmosphere.
The time frames, in which electrons travel within atoms, are unfathomably short. For example, electrons excited by light change their quantum-mechanical location within mere attoseconds. But how fast do electrons whiz across distances corresponding to the diameter of individual atomic layers?
Enzymes are catalysts that speed up chemical reactions in living organisms and control many cellular biological processes by converting a molecule, or substrate, into a product used by the cell. For scientists, understanding details of how enzymes work is essential to the discovery of drugs to cure diseases and treat disorders.
A team of researchers led by North Carolina State University has found that stacking materials that are only one atom thick can create semiconductor junctions that transfer charge efficiently, regardless of whether the crystalline structure of the materials is mismatched.
Univ. of Tennessee, Knoxville’s College of Engineering has made recent headlines for discoveries that, while atomically small, could impact our modern world. The team focused on the role of epilayer-substrate interactions in determining orientational relations in van der Waals epitaxy.
As the installation of photovoltaic solar cells continues to accelerate, scientists are looking for inexpensive materials beyond the traditional silicon that can efficiently convert sunlight into electricity. Theoretically, iron pyrite could do the job, but when it works at all, the conversion efficiency remains frustratingly low. Now, a Univ. of Wisconsin-Madison research team explains why that is.
A new crystallographic technique, called fast time-resolved crystallography, developed in the U.K. is set to transform scientists’ ability to observe how molecules work. Although this method, also known as Laue crystallography, has previously been possible, it has required advanced instrumentation that is only available at three sites worldwide. Only a handful of proteins have been studied using the traditional technique.
The key to creating a material that would be ideal for converting solar energy to heat is tuning the material’s spectrum of absorption just right: It should absorb virtually all wavelengths of light that reach Earth’s surface from the sun—but not much of the rest of the spectrum, since that would increase the energy that is reradiated by the material, and thus lost to the conversion process.
Diamonds aren’t just a girl’s best friend, they’re also R&D’s best friend—or at least a new acquaintance. Many laboratories and companies are embracing synthetic diamond for its elevated super properties in applications ranging from analytical instruments and biomedical sensors to electronics and lasers to water purification.
One of the most important molecules on Earth, calcium carbonate crystallizes into chalk, shells and minerals the world over. In a study led by Pacific Northwest National Laboratory, researchers used a powerful microscope that allows them to see the birth of crystals in real time, giving them a peek at how different calcium carbonate crystals form, they report in Science.
A new concept in metallic alloy design has yielded a multiple-element material that not only tests out as one of the toughest on record, but, unlike most materials, the toughness as well as the strength and ductility of this alloy actually improves at cryogenic temperatures. This multi-element alloy was synthesized and tested through a collaboration of researchers.
In the developing brain, special proteins that act like molecular tugboats push or pull on growing nerve cells, or neurons, helping them navigate to their assigned places amidst the brain’s wiring. How a single protein can exert both a push and a pull force to nudge a neuron in the desired direction is a longstanding mystery that has now been solved by scientists from Dana-Farber Cancer Institute.
Neurons communicate with each other through electrical signals that are generated by chemicals, which bind to structures on neurons called neuroreceptors. One neuroreceptor, called 5HT3-R, is involved in a variety of neurological disorders. Scientists in Switzerland have revealed for the first time the 3-D structure of this crucial neuroreceptor.
Biological physicists at Rice Univ. have succeeded in analyzing transmembrane protein folding in the same way they study the proteins’ free-floating, globular cousins. They have applied energy landscape theory to proteins that are hard to view because they are inside cell membranes. The method should increase the technique’s value to researchers who study proteins implicated in diseases and possibly in the creation of drugs to treat them.
Prothrombin is an inactive precursor for thrombin, a key blood-clotting protein, and is essential for life because of its ability to coagulate blood. Using x-ray crystallography, researchers have published the first image of this important protein. By removing disordered sections of the protein’s structure, scientists have revealed its underlying molecular mechanism for the first time.
The term “crowdsourcing” was coined in 2006 and since then has seen its definition broadened to a wide range of activities involving a network of people. A challenging problem that might benefit from crowdsourcing, according to recently published research, is the phase problem in x-ray crystallography. Retrieving the phase information has plagued many scientists for decades when trying to determine the crystal structure of a sample.
Researchers in Australia have discovered how algae that survive in very low levels of light are able to switch on and off a weird quantum phenomenon that occurs during photosynthesis. The function in the algae of this quantum effect, known as coherence, remains a mystery, but it is thought it could help them harvest energy from the sun much more efficiently.
Using synchrotron light, scientists have pioneered a new way to analyze delicate biomolecules. The new approach, called protein serial crystallography, is made possible by a new class of high-intensity x-ray sources called free-electron lasers and could reveal the atomic structure of proteins that were previously inaccessible to synchrotrons.
Using a doped-graphene matrix to slow down and then trap atoms of the precious metal osmium, researchers in the U.K. have shown the ability to control and quantify the growth of metal-crystals. When the trapped atoms come into contact with further osmium atoms they bind together, eventually growing into 3-D metal-crystals. They have called this new technique nanocrystallometry.
Melanin—and specifically, the form called eumelanin—is the primary pigment that gives humans the coloring of their skin, hair and eyes. It protects the body from the hazards of ultraviolet and other radiation that can damage cells and lead to skin cancer, but the exact reason why the compound is so effective at blocking such a broad spectrum of sunlight has remained something of a mystery.
The ability to control crystals with light and chemistry could lead to chameleon-style color-changing camouflage for vehicle bodies and other surfaces. Univ. of Michigan researchers discovered a template-free method for growing shaped crystals that allows for changeable structures that could appear as different colors and patterns.
Researchers from the NIST Center for Nanoscale Science and Technology have observed electromagnetically induced transparency at room temperature and atmospheric pressure in a silicon nitride optomechanical system. This work highlights the potential of silicon nitride as a material for producing integrated devices in which mechanical vibrations can be used to manipulate and modify optical signals.
An unwanted byproduct from a bygone method of glass production, the crystal devitrite could find a new use as an optical diffuser in medical laser treatments, communications systems and household lighting. For years, the properties of this material were not studied because it was considered as just a troublemaker in the glass-making process and needed to be eliminated.
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