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Categories: Chemistry: Inorganic Chemistry, Chemistry: Thermodynamics
Published Extending the playing field for organosulfurs: a new way to synthesize sulfinate esters
(via sciencedaily.com) Sulfinate esters, a type of organosulfur compounds, are typically synthesized using thiols. However, these substances are difficult to work with due to their unpleasant smell and oxidizability in air. Now, a research team has found a way to produce sulfinate esters through the direct oxidation of thioesters, which are easily accessible and stable. Their findings will help expand the field of organosulfur chemistry and hopefully lead to new applications in pharmaceuticals.
Published Grasping entropy: Teachers and students investigate thermodynamics through a hands-on model
(via sciencedaily.com) Though a cornerstone of thermodynamics, entropy remains one of the most vexing concepts to teach budding physicists in the classroom. Physics teachers designed a hand-held model to demonstrate the concept of entropy for students. Using everyday materials, the approach allows students to confront the topic with new intuition -- one that takes specific aim at the confusion between entropy and disorder.
Published Chemists devise a method for C-H activation of alcohols
(via sciencedaily.com) Chemists have extended a powerful molecule-building method -- called C-H activation -- to the broad class of chemicals known as alcohols.
Published How pulsating pumping can lead to energy savings
(via sciencedaily.com) Pumping liquids may seem like a solved problem but optimizing the process is still an area of active research. Any pumping application -- from industrial scales to heating systems at home -- would benefit from a reduction in energy demands. Researchers now showed how pulsed pumping can reduce both friction from and energy consumption of pumping. For this, they took inspiration from a pumping system intimately familiar to everyone: the human heart.
Published Pioneering beyond-silicon technology via residue-free field effect transistors
(via sciencedaily.com) Beyond-silicon technology demands ultra-high-performance field-effect transistors (FETs). Transition metal dichalcogenides (TMDs) provide an ideal material platform, but the device performances such as contact resistance, on/off ratio, and mobility are often limited by the presence of interfacial residues caused by transfer procedures. We show an ideal residue-free transfer approach using polypropylene carbonate (PPC) with a negligible residue for monolayer MoS2. By incorporating bismuth semimetal contact with atomically clean monolayer MoS2-FET on h-BN substrate, we obtain an ultralow Ohmic contact resistance approaching the quantum limit and a record-high on/off ratio of ~1011 at 15 K. Such an ultraclean fabrication approach could be the ideal platform for high-performance electrical devices using large-area semiconducting TMDs.
Published Deriving the fundamental limit of heat current in quantum mechanical many-particle systems
(via sciencedaily.com) Researchers have mathematically derived the fundamental limit of heat current flowing into a quantum system comprising numerous quantum mechanical particles in relation to the particle count. Further, they established a clearer understanding of how the heat current rises with increasing particle count, shedding light on the performance constraints of potential future quantum thermal devices.
Published Better cybersecurity with new material
(via sciencedaily.com) Digital information exchange can be safer, cheaper and more environmentally friendly with the help of a new type of random number generator for encryption. The researchers behind the study believe that the new technology paves the way for a new type of quantum communication.
Published Striking gold with molecular mystery solution for potential clean energy
(via sciencedaily.com) Hydrogen spillover is exactly what it sounds like. Small metal nanoparticles anchored on a thermally stable oxide, like silica, comprise a major class of catalysts, which are substances used to accelerate chemical reactions without being consumed themselves. The catalytic reaction usually occurs on the reactive -- and expensive -- metal, but on some catalysts, hydrogen atom-like equivalents literally spill from the metal to the oxide. These hydrogen-on-oxide species are called 'hydrogen spillover.'
Published Peering into nanofluidic mysteries one photon at a time
(via sciencedaily.com) Original source Researchers have revealed an innovative approach to track individual molecule dynamics within nanofluidic structures, illuminating their response to molecules in ways never before possible.
Published A step closer to digitizing the sense of smell: Model describes odors better than human panelists
(via sciencedaily.com) A main crux of neuroscience is learning how our senses translate light into sight, sound into hearing, food into taste, and texture into touch. Smell is where these sensory relationships get more complex and perplexing. To address this question, a research team are investigating how airborne chemicals connect to odor perception in the brain. They discovered that a machine-learning model has achieved human-level proficiency at describing, in words, what chemicals smell like.
Published Growing triple-decker hybrid crystals for lasers
(via sciencedaily.com) By controlling the arrangement of multiple inorganic and organic layers within crystals using a novel technique, researchers have shown they can control the energy levels of electrons and holes (positive charge carriers) within a class of materials called perovskites. This tuning influences the materials' optoelectronic properties and their ability to emit light of specific energies, demonstrated by their ability to function as a source of lasers.
Published Watching a bimetallic catalytic surface in action
(via sciencedaily.com) A team of researchers addressed the question: what happens to a Ga-promoted Cu surface under reaction conditions required for the synthesis of methanol? They found complex structural transformations of this bimetallic catalyst that might change the common view on the catalytically active surface structure.
Published Taking photoclick chemistry to the next level
(via sciencedaily.com) Researchers have been able to substantially improve photoclick chemistry. They were able to boost the reactivity of the photoclick compound in the popular PQ-ERA reaction through strategic molecular substitution. They now report a superb photoreaction quantum yield, high reaction rates and notable oxygen tolerance.
Published Surpassing the human eye: Machine learning image analysis rapidly determines chemical mixture composition
(via sciencedaily.com) Machine learning model provides quick method for determining the composition of solid chemical mixtures using only photographs of the sample.
Published A new way to capture and recycle carbon dioxide from industrial emissions
(via sciencedaily.com) Carbon capture is a promising method to help slow climate change. With this approach, carbon dioxide (CO¬¬2) is trapped before it escapes into the atmosphere, but the process requires a large amount of energy and equipment. Now, researchers have designed a capture system using an electrochemical cell that can easily grab and release CO2. The device operates at room temperature and requires less energy than conventional, amine-based carbon-capture systems.
Published New 'droplet battery' could pave the way for miniature bio-integrated devices
(via sciencedaily.com) Researchers have developed a miniature battery that could be used to power tiny devices integrated into human tissues. The design uses an ionic gradient across a chain of droplets -- inspired by how electric eels generate electricity. The device was able to regulate the biological activity of human neurons. This could open the way to the development of tiny bio-integrated devices, with a range of applications in biology and medicine.
Published Hotter quantum systems can cool faster than initially colder equivalents
(via sciencedaily.com) The Mpemba effect is originally referred to the non-monotonic initial temperature dependence of the freezing start time, but it has been observed in various systems -- including colloids -- and has also become known as a mysterious relaxation phenomenon that depends on initial conditions. However, very few have previously investigated the effect in quantum systems. Now, the temperature quantum Mpemba effect can be realized over a wide range of initial conditions.
Published A first for ferrocene: Organometallic capsule with unusual charge-transfer interactions
(via sciencedaily.com) An organometallic capsule that can reversibly assemble and disassemble in response to chemical stimuli was recently developed by chemists. Comprising ferrocene-based bent amphiphiles, this new capsule can act as a host for various types of guest molecules, such as electron acceptors and dyes. Thanks to the controllable release of its cargo, the capsule would find applications in catalysis, medicine, and biotechnology.
Published Direct power generation from methylcyclohexane using solid oxide fuel cells
(via sciencedaily.com) Original source Methylcyclohexane is very promising as a hydrogen carrier that can safely and efficiently transport and store hydrogen. However, the dehydrogenation process using catalysts has issues due to its durability and large energy loss. Recently, researchers have succeeded in using solid oxide fuel cells to generate electricity directly from methylcyclohexane and recover toluene for reuse. This research is expected to not only reduce energy requirements but also explore new chemical synthesis by fuel cells.
Published Quantum computer unveils atomic dynamics of light-sensitive molecules
(via sciencedaily.com) Researchers have implemented a quantum-based method to observe a quantum effect in the way light-absorbing molecules interact with incoming photons. Known as a conical intersection, the effect puts limitations on the paths molecules can take to change between different configurations. The observation method makes use of a quantum simulator, developed from research in quantum computing, and offers an example of how advances in quantum computing are being used to investigate fundamental science.