http://phys.org/ en-us Phys.org internet news portal provides the latest news on science including: Physics, Nanotechnology, Life Sciences, Space Science, Earth Science, Environment, Health and Medicine. (Phys.org) —Reach for a tall glass of iced tea. Don't drink. Look at the glass instead. The glass is an amorphous solid, consisting of molecules jumbled in disarray. It's the complete opposite of the ice in your drink. Ice is a crystalline solid made up of water molecules arranged in a repeat pattern. http://phys.org/news286617671.html Physics Wed, 01 May 2013 09:01:17 EST news286617671 Applying femtosecond X-ray methods, researchers at the Max-Born-Institute in Berlin (Germany) and the Ecole Polytechnique Federale de Lausanne (Switzerland) observed an extremely fast, collective electron transfer of ~100 molecular ions after excitation of a single electron in a crystal of transition metal complexes. http://phys.org/news285408964.html Physics Wed, 17 Apr 2013 09:16:13 EST news285408964 Whether gas trapped under a frozen water layer flows through cracks or bursts out depends on the layer's depth and temperature, according to scientists at Pacific Northwest National Laboratory. The water isn't crystalline ice; it is amorphous solid water, which is disordered and often described as a "frozen" liquid. The team proved that in some cases, gases trapped under amorphous water films are released via fissures that form during crystallization. For thicker trapped gas layers, the gas can escape abruptly before crystallization. This work graced a cover of The Journal of Chemical Physics. http://phys.org/news285229426.html Physics Mon, 15 Apr 2013 07:40:05 EST news285229426 New findings on the growth of ice clusters in Polar Stratospheric Clouds could help clarify the process of ozone depletion in the atmosphere. http://phys.org/news262861166.html Space & Earth Mon, 30 Jul 2012 09:59:35 EST news262861166 (Phys.org) -- Krzysztof Szalewicz, professor of physics and astronomy at the University of Delaware, and Rafal Podeszwa of the University of Silesia Institute of Chemistry in Poland have developed and validated a more accurate method for predicting the interaction energy of large molecules, such as biomolecules used to develop new drugs. http://phys.org/news256382564.html Chemistry Wed, 16 May 2012 10:23:09 EST news256382564 By delving into the interactions between a hydrogen molecule and muonic hydrogen, the heaviest hydrogen isotope to date, a team of researchers from academia and Pacific Northwest National Laboratory created a popular paper. http://phys.org/news249206950.html Chemistry Thu, 23 Feb 2012 08:30:01 EST news249206950 Lead sulfide (PbS) forms when an equal number of lead and sulfur atoms exchange electrons and bond together in cubic crystals. Now scientists have determined that a structure comprising 32 lead-sulfur pairs is the smallest possible cubic arrangement that exhibits the same coordination as bulk lead sulfide. (The coordination number is the number of nearest neighbors each atom in the crystal has.) http://phys.org/news246040210.html Physics Tue, 17 Jan 2012 16:40:02 EST news246040210 Hydrogen, normally a gas, may act like a metal when squeezed under extreme pressure. In that state, competing chemical and physical effects determine its properties, said Nobel laureate Roald Hoffmann, Cornell's Frank H.T. Rhodes Professor in Humane Letters and professor emeritus of chemistry. http://phys.org/news237803678.html Physics Fri, 14 Oct 2011 09:39:15 EST news237803678 Rapid cooling of ordinary water or compression of ordinary ice: either of these can transform normal H2O into an exotic substance that resembles glass in its transparency, brittleness, hardness, and luster. Unlike everyday ice, which has a highly organized crystalline structure, this glass-like material's molecules are arranged in a random, disorganized way. Scientists have studied glassy water for decades, but the exact temperature at which water acquires glass-like properties has been the subject of heated debate for years, due to the difficulty of manipulating pure glassy water in laboratories. http://phys.org/news236254236.html Physics Mon, 26 Sep 2011 11:10:47 EST news236254236 Benzocaine, a commonly used local anesthetic, may more easily wiggle into a cell's membrane when the membrane is made up of compounds that carry a negative charge, a new study shows. The finding could help scientists piece together a more complete understanding of the molecular-level mechanisms behind pain-blocking medicines, possibly leading to their safer and more effective use. http://phys.org/news236254009.html Chemistry Mon, 26 Sep 2011 11:07:03 EST news236254009 (PhysOrg.com) -- Knowing the structure of a molecule is an important part of understanding it, but quite often it’s even more important to know how the molecule moves -- more specifically, the vibrational dynamics that drive and control its interactions with other molecules in chemical reactions. That’s particularly true of proteins, the enormously complex molecular structures found at the heart of important life processes such as cell signaling, ion transport, and other functions. But most of the available techniques for studying the vibrational properties of a protein run into some vexing limitations, especially when probing the lower frequencies at which the proteins actually do their job. http://phys.org/news234696151.html Physics Thu, 08 Sep 2011 11:10:01 EST news234696151 Water and ice may not be among the first things that come to mind when you think about single-walled carbon nanotubes (SWCNTs), but a Japan-based research team hoping to get a clearer understanding of the phase behavior of confined water in the cylindrical pores of carbon nanotubes zeroed in on confined water's properties and made some surprising discoveries. http://phys.org/news227976548.html Nanotechnology Wed, 22 Jun 2011 15:49:39 EST news227976548 Protein molecules inside cells are constantly reorganizing themselves, driven by very tiny forces exerted by all the other molecules in their crowded environment. Most experimental techniques and theoretical/computational models are necessarily built around much greater driving forces. A new theoretical model reported in the Journal of Chemical Physics investigates the unfolding of fibronectin under gentler conditions. http://phys.org/news205490452.html Chemistry Tue, 05 Oct 2010 10:00:01 EST news205490452 Polymer-based photovoltaic cells have some real advantages compared to the currently used semiconductor-based cells. They are easy to make and the materials are cheap. The challenge is to figure out how to make efficient cells while keeping the manufacturing cost low. http://phys.org/news204910237.html Chemistry Tue, 28 Sep 2010 16:30:58 EST news204910237 At its most basic level, understanding chemistry means understanding what electrons are doing. Research published in the Journal of Chemical Physics not only maps the movement of electrons in real time but also observes a concerted electron and proton transfer that is quite different from any previously known phase transitions in the model crystal, ammonium sulfate. By extending X-ray powder diffraction into the femtosecond realm, the researchers were able to map the relocation of charges in the ammonium sulfate crystal after they were displaced by photoexcitation. http://phys.org/news204267085.html Physics Tue, 21 Sep 2010 05:51:46 EST news204267085 Because one of the main bottlenecks in determining the structure of protein molecules is producing good isolated single crystals, improved crystallization techniques would be useful in a wide range of genomics and pharmaceutical research. http://phys.org/news203674576.html Physics Tue, 14 Sep 2010 09:16:43 EST news203674576 An octopus-like polymer can "walk" along the wall of a narrow channel as it is pushed through by a solvent. Now research in The Journal of Chemical Physics, which is published by the American Institute of Physics, provides a theoretical model that compares the transport characteristics of straight- and branched-chain polymers in smooth channels as well as in channels whose walls interact with the polymer -- work that could aid in the development of carrier molecules for delivering drugs at a controlled rate in the body. http://phys.org/news200070721.html Chemistry Tue, 03 Aug 2010 16:12:17 EST news200070721 (PhysOrg.com) -- Polymer strands wriggle their way through nanometer-sized pores in a membrane to get from here to there and do their jobs. New theoretical research by Rice University scientists quantifies precisely how long the journey takes. http://phys.org/news199635756.html Nanotechnology Thu, 29 Jul 2010 16:10:01 EST news199635756 Drug delivery inside the body is a complicated process. Compounds travel through a maze of aqueous solutions, lipid membranes, and barriers between the blood and tissues like the brain. Research reported in the American Institute of Physics publication the Journal of Chemical Physics presents a theoretical model that accurately predicts the hydration free energy (HFE) of a wide variety of organic compounds. http://phys.org/news199468194.html Chemistry Tue, 27 Jul 2010 16:50:07 EST news199468194 Recently, academic debate has been swirling around the existence of unusual quantum mechanical effects in the most ubiquitous of phenomena, including photosynthesis, the process by which organisms convert light into chemical energy. http://phys.org/news198945939.html Physics Wed, 21 Jul 2010 15:45:53 EST news198945939 The movement of long chain polymers through nanopores is a key part of many biological processes, including the transport of RNA, DNA, and proteins. New research reported in The Journal of Chemical Physics, which is published by the American Institute of Physics, describes an improved theoretical model for this type of motion. http://phys.org/news198318870.html Chemistry Wed, 14 Jul 2010 10:10:01 EST news198318870 Research reported in The Journal of Chemical Physics, which is published by the American Institute of Physics, provides the first real-time measurements of the time dependence of the individual steps of dissociation of a complex consisting of two rare gas atoms and a halogen molecule. http://phys.org/news198318262.html Physics Wed, 14 Jul 2010 09:24:42 EST news198318262 (PhysOrg.com) -- All proteins self-assemble in a fraction of the blink of an eye, but it can take a long time to mimic the process. And there has been no guarantee of success, even with the most powerful computers - until now. http://phys.org/news197658752.html Chemistry Tue, 06 Jul 2010 18:12:53 EST news197658752 Old glass is not the same as new glass -- and the difference is not just due to manufacturing techniques. Unlike crystalline solids, glasses change as they age, increasing packing density and stability. Ideally, a glass should be cooled slowly, maybe over 10,000 years or so, but that is not usually practical. http://phys.org/news197048921.html Physics Tue, 29 Jun 2010 17:10:02 EST news197048921 As you go about your day-to-day activities, tiny bubbles of nitrogen come and go inside your tissues. This is not a problem unless you happen to experience large changes in ambient pressure, such as those encountered by scuba divers and astronauts. During large, fast pressure drops, these bubbles can grow and lead to decompression sickness, popularly known as "the bends." http://phys.org/news196442169.html Physics Tue, 22 Jun 2010 16:16:26 EST news196442169 An understanding of particle diffusion in the presence of constrictions is essential in fields as diverse as drug delivery, cellular biology, nanotechnology, materials engineering, and spread of pollutants in the soil. When a driving force is applied, displacement of particles occurs as well as diffusion. http://phys.org/news195901827.html Physics Wed, 16 Jun 2010 11:10:01 EST news195901827 The secret life of water just got weirder. For years water has been known to exist in 15 phases -- not just the merry threesome of solid, liquid and gas from grade school science. Now, University of Utah chemists have confirmed the coexistence of ice and liquid after water crystallizes at very low temperatures. http://phys.org/news195901507.html Physics Wed, 16 Jun 2010 10:05:21 EST news195901507 By mixing and matching choices from a buffet of 30 to 70 options, scientists are modeling water's behavior in surface and subsurface reactions and in heterogeneous atmospheric processes such as the formation of clouds. But, how accurate are the models built with this approach, known as density functional theory (DFT)? http://phys.org/news189329799.html Chemistry Thu, 01 Apr 2010 08:50:01 EST news189329799 (PhysOrg.com) -- Combining experimental and theoretical methods, scientists at the Pacific Northwest National Laboratory gained a more complete picture of the electronic structure of a stable, soluble uranium ion and the bonds it forms. This study included an important first: the first nuclear magnetic resonance (NMR) spectroscopy data for solid UO22+. Previous studies examined the ion in the liquid state. The new data provided insights into how the elements bond together to form molecules and how the molecules combine to form clusters. http://phys.org/news187979566.html Chemistry Tue, 16 Mar 2010 18:00:03 EST news187979566 (PhysOrg.com) -- Most parts of living organisms come packaged with ribbons. The ribbons are proteins—chains of amino acids that must fold into three-dimensional structures to work properly. But when for any reason the ribbons fold incorrectly, bad things can happen, and in humans misfolded-protein disorders include Alzheimer's and Parkinson's diseases. http://phys.org/news168097445.html Physics Wed, 29 Jul 2009 15:00:06 EST news168097445