jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Yoyo Hinuma | Takashi Toyao | Takashi Kamachi | Zen Maeno | Satoru Takakusagi | Shinya Furukawa | Ichigaku Takigawa | Ken‐ichi Shimizu
Source: The Journal of Physical Chemistry (article, 2018-01-01)
Field: Materials Science — Materials Chemistry

Density Functional Theory Calculations of Oxygen Vacancy Formation and Subsequent Molecular Adsorption on Oxide Surfaces The surface oxygen vacancy formation energy (EOᵥₐc) is an important parameter in determining the catalytic activity of metal oxides. Estimating these energies can therefore lead to data-driven design of promising catalyst candidates. In the present study, we determine EOᵥₐc for various insulating and semiconducting oxides. Statistical investigations indicate that the band gap, bulk formation energy, and electron affinity are factors that strongly influence EOᵥₐc. Electrons enter defect states after O desorption, and these states can be in the valence band, mid-gap, or in the conduction band. Subsequent adsorption of O₂, NO, CO, CO₂, and H₂ molecules on an O-deficient surface is also investigated. These molecules become preferentially adsorbed at the defect sites, and EOᵥₐc is identified as the dominant factor that determines the adsorption mode as well as a descriptor that shows good correlation with the adsorption energy. Chemistry ; Adsorption ; Band gap ; Oxide ; Desorption ; Density functional theory ; Oxygen ; Catalysis ; Molecule ; Vacancy defect ; Valence (chemistry) ; Metal ; Chemical physics ; Density of states ; Physical chemistry ; Inorganic chemistry ; Computational chemistry ; Crystallography ; Condensed matter physics ; Organic chemistry Catalytic Processes in Materials Science ; Machine Learning in Materials Science ; Gas Sensing Nanomaterials and Sensors
Authors: Vinay I. Hegde | Muratahan Aykol | Kirklin, Scott | Wolverton, Chris
Source: arXiv (Cornell University) (article, 2018-08-31)
Field: Materials Science — Materials Chemistry

The Phase Stability Network of all Inorganic Materials One of the holy grails of materials science, unlocking structure-property relationships, has largely been pursued via bottom-up investigations of how the arrangement of atoms and interatomic bonding in a material determine its macroscopic behavior. Here we consider a complementary approach, a top-down study of the organizational structure of networks of materials, based on the interaction between materials themselves. We unravel the complete "phase stability network of all inorganic materials" as a densely-connected complex network of 21,000 thermodynamically stable compounds (nodes) interlinked by 41 million tie-lines (edges) defining their two-phase equilibria, as computed by high-throughput density functional theory. We find that the node connectivity in the materials network has a lognormal distribution, and the connectivity decreases with the number of elemental constituents in a material. Analyzing the topology of this network of materials has the potential to uncover new knowledge inaccessible from traditional atoms-to-materials paradigms. Using the connectivity of nodes in the phase stability network, we derive a rational, data-driven metric for material reactivity, the "nobility index", and quantitatively identify the noblest materials in nature. Phase (matter) ; Materials science ; Stability (learning theory) ; Chemical engineering ; Chemistry ; Computer science ; Engineering ; Organic chemistry X-ray Diffraction in Crystallography ; Material Science and Thermodynamics ; Solidification and crystal growth phenomena
Authors: Christian Wülker | Gregory S. Chirikjian
Source: arXiv (Cornell University) (preprint, 2018-11-28)
Field: Materials Science — Biomaterials

Quantizing Euclidean motions via double-coset decomposition Concepts from mathematical crystallography and group theory are used here to quantize the group of rigid-body motions, resulting in a "motion alphabet" with which to express robot motion primitives. From these primitives it is possible to develop a dictionary of physical actions. Equipped with an alphabet of the sort developed here, intelligent actions of robots in the world can be approximated with finite sequences of characters, thereby forming the foundation of a language in which to articulate robot motion. In particular, we use the discrete handedness-preserving symmetries of macromolecular crystals (known in mathematical crystallography as Sohncke space groups) to form a coarse discretization of the space $\rm{SE}(3)$ of rigid-body motions. This discretization is made finer by subdividing using the concept of double-coset decomposition. More specifically, a very efficient, equivolumetric quantization of spatial motion can be defined using the group-theoretic concept of a double-coset decomposition of the form $\Gamma \backslash \rm{SE}(3) / \Delta$, where $\Gamma$ is a Sohncke space group and $\Delta$ is a finite group of rotational symmetries such as those of the icosahedron. The resulting discrete alphabet is based on a very uniform sampling of $\rm{SE}(3)$ and is a tool for describing the continuous trajectories of robots and humans. The general "signals to symbols" problem in artificial intelligence is cast in this framework for robots moving continuously in the world, and we present a coarse-to-fine search scheme here to efficiently solve this decoding problem in practice. Group (periodic table) ; Mathematics ; Euclidean group ; Rigid body ; Motion (physics) ; Homogeneous space ; Discretization ; Symmetry group ; Euclidean space ; Pure mathematics ; Computer science ; Mathematical analysis ; Artificial intelligence ; Geometry ; Physics ; Classical mechanics ; Quantum mechanics Diatoms and Algae Research ; Enzyme Structure and Function ; Supramolecular Self-Assembly in Materials
Authors: Jeffrey L. Krichmar | William Severa | Salar M. Khan | John Olds
Source: arXiv (Cornell University) (preprint, 2018-12-03)
Field: Materials Science — Materials Chemistry

Making BREAD: Biomimetic strategies for Artificial Intelligence Now and\n in the Future The Artificial Intelligence (AI) revolution foretold of during the 1960s is\nwell underway in the second decade of the 21st century. Its period of\nphenomenal growth likely lies ahead. Still, we believe, there are crucial\nlessons that biology can offer that will enable a prosperous future for AI. For\nmachines in general, and for AI's especially, operating over extended periods\nor in extreme environments will require energy usage orders of magnitudes more\nefficient than exists today. In many operational environments, energy sources\nwill be constrained. Any plans for AI devices operating in a challenging\nenvironment must begin with the question of how they are powered, where fuel is\nlocated, how energy is stored and made available to the machine, and how long\nthe machine can operate on specific energy units. Hence, the materials and\ntechnologies that provide the needed energy represent a critical challenge\ntowards future use-scenarios of AI and should be integrated into their design.\nHere we make four recommendations for stakeholders and especially decision\nmakers to facilitate a successful trajectory for this technology. First, that\nscientific societies and governments coordinate Biomimetic Research for\nEnergy-efficient, AI Designs (BREAD); a multinational initiative and a funding\nstrategy for investments in the future integrated design of energetics into AI.\nSecond, that biomimetic energetic solutions be central to design consideration\nfor future AI. Third, that a pre-competitive space be organized between\nstakeholder partners and fourth, that a trainee pipeline be established to\nensure the human capital required for success in this area.\n Multinational corporation ; Stakeholder ; Energy (signal processing) ; Artificial intelligence ; Computer science ; Pipeline (software) ; Operations research ; Business ; Engineering ; Economics ; Management Machine Learning in Materials Science ; Fuel Cells and Related Materials
Authors: Won Bin Im | Yoon Hwa Kim | Ha Jun Kim | Zhenbin Wang | Jungmin Ha | Joanna McKittrick | Shyue Ping Ong
Source: ECS Meeting Abstracts (article, 2018-07-23)
Field: Materials Science — Materials Chemistry

(Invited) Data-Mining, a New Sr<sub>2</sub>LiAlO<sub>4</sub>:Eu<sup>2+</sup>/Ce<sup>3+</sup> Phosphor for Solid-State Lighting Applications There is a critical need for new earth-abundant phosphors to enable next-generation, highly efficient solid-state lighting. Here, we report the discovery of Sr 2 LiAlO 4 , the first known Sr-Li-Al-O quaternary crystal, via a carefully-targeted data-driven structure prediction and screening effort using density functional theory calculations. Sr 2 LiAlO 4 is predicted and experimentally confirmed to be a thermodynamically and thermally stable phosphor host that can be excited with near-UV/blue sources. The Eu 2+ and Ce 3+ -activated Sr 2 LiAlO 4 phosphors exhibit broad emissions at l max ~ 512 nm (green-yellow) and l max ~ 434 nm (blue), respectively, with excellent thermal quenching resistance of &gt; 88% intensity at 150°C. A prototype phosphor-converted white LED utilizing Sr 2 LiAlO 4 -based phosphors yields an excellent color rendering index exceeding 90. Sr 2 LiAlO 4 therefore exhibits great potential for industrial applications in low-cost, high-color-quality WLEDs. Figure 1 Phosphor ; Excited state ; Color rendering index ; Materials science ; Solid-state ; Analytical Chemistry (journal) ; Crystal structure ; Optoelectronics ; Chemistry ; Crystallography ; Physics ; Physical chemistry ; Atomic physics Luminescence Properties of Advanced Materials
Authors: Bosen Qian
Source: TUScholarShare (Temple University) (article, 2018-01-01)
Field: Materials Science — Materials Chemistry

Theoretical and Numerical Study of Transverse Thermoelectrics Thermoelectric materials are capable of direct conversion of thermal energy to electrical energy and vice versa. Their applications include thermoelectric coolers, generators, as well as sensors. Conventional thermoelectric devices consist of multiple units of p-type and n-type semiconducting elements, in which electrical current and heat flux flow parallel to each other. In contrast, transverse thermoelectric devices could decouple electrical current and heat flux such that they flow perpendicular to each other. Transverse thermoelectricity could be realized in single-phase anisotropic materials or composite materials with engineered anisotropy. Studies have shown that composite transverse thermoelectric materials could provide a better performance than their single-phase counterparts. In this dissertation proposal, two configurations of transverse thermoelectric composites are examined using both analytical and numerical methods. Mathematical models are established to calculate the effective properties of anisotropic thermoelectric composites by analyzing the representative unit cells using the Kirchhoff circuit law (KCL) and the Thevenin’s theorem followed by tensor transformation. Thermoelectric figure of merit (ZT), power factor, as well as cooling performance (maximum cooling temperature ΔTmax) of transverse thermoelectrics are studied. Comparisons between the mathematical models and numerical simulation showed good agreement, while some discrepancies are observed and discussed. Since transverse composite thermoelectrics can decouple the electrical and thermal transports, they can offer new opportunities for device design including thin film sensors and cascading coolers, as well as for performance enhancement such as improved power factors. Transverse plane ; Thermoelectric materials ; Physics ; Materials science ; Engineering physics ; Thermoelectric effect ; Engineering ; Thermodynamics ; Structural engineering Advanced Thermoelectric Materials and Devices ; Thermal properties of materials ; Thermography and Photoacoustic Techniques
Authors: Alberto Baggioli | Antonino Famulari
Source: Virtual Community of Pathological Anatomy (University of Castilla La Mancha) (article, 2018-01-01)
Field: Chemistry — Organic Chemistry

Can a whole nanoparticle accurately describe a single C60 fullerene when it comes to weak electrostatic interactions technologically-relevant processes, from printing and powder coating to the removal of fine dust from coal-fired power plant emissions. C60 fullerene, owing to its peculiar mechanical and electronic properties, has been oftentimes used as a model nanoparticle in the study of e.g. cluster conductivity and Coulomb fission, allowing for a deeper understanding on e.g. cluster polarizability and charge transfer among spherical or nearly-spherical particles.&#13;\nSeveral classical models describing the interaction between two spherical particles or a spherical particle and a point charge can be found in literature, involving either metallic or dielectric particles [1]. However, attaching macroscopic properties, such as dielectric or metallic character, to a nanometer-sized object is not straightforward. The C60 case has in fact spawned what is now an on-going debate on the matter [2-6].&#13;\nIn this talk, new insights from DFT simulation of neutral C60 molecules interacting with selected electron donors and acceptors are presented, and compared to both literature model interactions (in which point charges are preferred to chemically meaningful ligands) and classical model interactions.&#13;\n[1] E.B. Lindgren et al. Phys. Chem. Chem. Phys. 18 (2016) 5883.&#13;\n[2] A.J. Stace et al. Phys. Chem. Chem. Phys. 13 (2011) 18339.&#13;\n[3] H. Zettergren et al. Phys. Chem. Chem. Phys. 14 (2012) 16360.&#13;\n[4] G. Raggi et al. Phys. Chem. Chem. Phys. 15 (2013) 20115.&#13;\n[5] H. Zettergren et al. Phys. Chem. Chem. Phys. 16 (2014) 14969.&#13;\n[6] F. Lindén et al. J. Chem. Phys. 145 (2016) 194307. Fullerene ; Nanoparticle ; Nanotechnology ; Physics ; Materials science Fullerene Chemistry and Applications ; Nanotechnology research and applications ; Carbon Nanotubes in Composites
Authors: Meysam Karami Rad
Source: Preprints.org (review, 2018-08-14)
Field: Materials Science — Materials Chemistry

Effect of Transport Properties on Thermoelectric Generators Design, A review Abstract Due to the relatively low efficiency of thermoelectric (TE) generators, they have mostly been used in niche applications where the unique properties of TE generators outweigh their lack of efficiency, or conditions where it is more reasonable to base the optimal design on maximum generated power rather than maximum efficiency. The aim of this work is to investigate how the different fundamental transport properties (Seebeck coefficient, thermal conductivity and electrical resistivity) in materials with equal figure of merit (ZT) impact TE module design and maximum power output. Further, we discuss and review the strategies to enhance material properties and the latest studies on the TE module performance. It is shown, that by increasing the power factor by a factor of 15 and decreasing the thermal conductivity by 13.33 in order to maintain ZT=1, power output is increased by 45%. This effect is stronger in lower module fill factor and thermal resistance of the heat source and heat sink. Figure of merit ; Thermal conductivity ; Thermoelectric generator ; Thermoelectric effect ; Power factor ; Heat sink ; Materials science ; Seebeck coefficient ; Thermoelectric materials ; Work (physics) ; Maximum power principle ; Engineering physics ; Thermal resistance ; Thermal ; Energy conversion efficiency ; Electrical resistivity and conductivity ; Power (physics) ; Electrical engineering ; Optoelectronics ; Mechanical engineering ; Thermodynamics ; Composite material ; Physics ; Engineering Advanced Thermoelectric Materials and Devices ; Thermal properties of materials ; Thermal Radiation and Cooling Technologies
Authors: Yufei Chen | Chengbao Geng | Yang Han | Mingzhuo Chai | Hongyuan Guo | Chunyan Yue | Yingyi Ma
Source: Journal of Nanomaterials (article, 2018-11-19)
Field: Materials Science — Polymers and Plastics

Micromorphology and Mechanical and Dielectric Properties of Bismaleimide Composite Modified by Multiwalled Carbon Nanotubes and Polyethersulfone Multiwalled carbon nanotubes (MWCNTs) were modified by oxidizing agent to obtain O-MWCNTs, and the surface of it was coated with active group. 4,4<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M1"><mml:msup><mml:mrow/><mml:mrow><mml:mo>′</mml:mo></mml:mrow></mml:msup></mml:math>-Diaminodiphenylmethane bismaleimide (MBMI) was used as matrix, 3,3<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M2"><mml:msup><mml:mrow/><mml:mrow><mml:mo>′</mml:mo></mml:mrow></mml:msup></mml:math>-diallyl bisphenol A (BBA) and bisphenol-A diallyl ether (BBE) were used as reactive diluent, polyethersulfone (PES) as toughening agent, and O-MWCNTs as modifier; OMWCNT/PES-MBAE composite was prepared through in situ sol-gel method. The effect of PES and OMWCNTs on the mechanical and dielectric properties of composite was analyzed, and the microstructure was examined by transmission electron microscope (TEM) and scanning electron microscope (SEM). The mechanism of composite toughened by PES and OMWCNTs was observed and analyzed. The results showed that Diels-Alder reaction between MBMI and allyl compounds occurred completely and unsaturated double bond disappeared. O-MWCNTs and PES resin dispersed smoothly in polymer matrix and were used as reinforcement, and PES resin and O-MWCNTs could synergistically improve the properties of the composite and exhibited a typical ductile fracture. The impact and bending strengths were 16.09 kJ/m 2 and 153.57 MPa, which were 74.32% and 53.08% higher than those of the MBAE matrix, respectively, and the dielectric constant and the dielectric loss were 3.76 (100 Hz) and 2.79 × 10 −3 (100 Hz), when the content of PES was 2 wt% and O-MWCNTs was 0.02 wt%. The outstanding properties of the material made it play an important role in high-performance insulating material applications. Materials science ; Composite number ; Composite material ; Scanning electron microscope ; Microstructure Synthesis and properties of polymers ; Epoxy Resin Curing Processes ; Polymer Nanocomposites and Properties
Authors: Alexander Ruf
Source: mediaTUM – the media and publications repository of the Technical University Munich (Technical University Munich) (article, 2018-01-01)
Field: Chemistry — Spectroscopy

Previously unknown organomagnesium compounds in astrochemical context In the course of these years, I have relied on the Quantum chemical ; Context (archaeology) ; Chemical stability ; Astrochemistry ; Fragmentation (computing) ; Chemistry ; Chemical process ; Meteorite ; Molecule ; Astrobiology ; Nanotechnology ; Chemical space ; Physics ; Chemical physics ; Astrophysics ; Materials science ; Organic chemistry ; Computer science ; Interstellar medium ; Galaxy ; Drug discovery Mass Spectrometry Techniques and Applications ; Chemical Reactions and Mechanisms ; Chemical Reaction Mechanisms
Authors: Emil Gustavsson
Source: Gothenburg University Publications Electronic Archive (Gothenburg University) (article, 2018-11-15)
Field: Chemistry — Spectroscopy

Isotope labeling of proteins for spectroscopic studies Protein structural dynamics have been closely tied to the molecular mechanisms controlling for example enzyme activities. In my work, I have mainly studied the bacteriophytochrome from Deinococcus radiodurans. Phytochromes are photoreceptors that monitor the level, intensity, duration and color of environmental light to regulate numerous fundamental photomorphogenic processes in plants, fungi, and bacteria. In order to monitor the dynamic nature of such proteins, they are preferably investigated in solution. NMR and IR spectroscopy are ideal techniques for studying proteins in solution, but can suffer from spectral overlap on larger systems. To investigate large proteins, such as the phytochromes studied in this thesis, biochemical modifications can be applied. Introduction of isotopes, either uniformly, amino acid-selectively or site-selectively make it possible to study the dynamics of large proteins even down to selected residues. In this thesis, I developed and applied uniform, amino acid-selective and site-selective methods to isotopically label proteins, primarily a bacteriophytochrome. Solution NMR and IR spectroscopy were then applied to probe the structural dynamics of these proteins. The investigations reveal both how structural heterogeneity couples to the photomodulation in phytochromes, and how isomerization of the chromophore is linked to the global structural rearrangement in the sensory receptor. Further, the bacteriophytochrome knot region was investigated, and the results suggest the knot as a novel signaling pathway in phytochromes. Site-selective isotope labeling, together with femtosecond IR spectroscopy, could also confirm an intermediate state in GFP fluorescent signaling. My work has enabled spectroscopic investigations to monitor active sites and structural dynamics of proteins in a highly selective manner. It revealed structural and dynamical information underpinning the function of phytochrome photoreceptors. Isotope ; Chemistry ; Radiochemistry ; Physics ; Nuclear physics Mass Spectrometry Techniques and Applications ; Metabolism and Genetic Disorders ; Amino Acid Enzymes and Metabolism
Authors: W Thiel | Y Nanba | T Ishimoto | M Koyama | Q Li | R Garcia-Muelas | N Lopez | K Bourzac | R Service | M Giles | Y Suchorski | S Grnborg | T Stecher | K Reuter | H Oberhofer | M Mellmer | K Voitchovsky | D Giofre | J Segura | F Stellacci | M Ceriotti | R Gaillac | A Kubas | E Kolsbjerg | A Peterson | B Hammer | T Markland | D Tabor
Source: Nature Catalysis (article, 2018-08-07)
Field: Materials Science — Materials Chemistry

Powering catalysis with supercomputers Catalysis ; Chemistry ; Nanotechnology ; Computer science ; Materials science ; Organic chemistry Machine Learning in Materials Science ; Electrocatalysts for Energy Conversion ; Hydrogen Storage and Materials
Authors: Khidhir Alhameedi | Björn Bohman | Amir Karton | Dylan Jayatilaka
Source: RUNE (Research UNE) (article, 2018-02-14)
Field: Chemistry — Spectroscopy

Predicting the primary fragments in mass spectrometry using ab initio Roby–Gould bond indices There is currently a lack of computational methods supporting the elucidation of unknown compounds by mass spectrometry. In this study, we develop and evaluate seven different protocols, based on the ab initio Roby-Gould bond indices [Gould et al., Theor. Chem. Acc., 2008, 119, 275] for predicting the mass-to-charge ratio of the highest intensity peak (base peak) in electron impact mass spectra. The protocols are applied to a dataset of 75 molecules, including five directly targeted semiochemicals. The Roby-Gould bond indices are also surveyed exhaustively, for the first time, for a dataset of 103 molecules with 682 C-C bonds. For neutral species we find that the bond indices are, as may be expected, highly correlated with the bond length; for cations, although there is a correlation, the bond indices are more variable. One of our protocols, protocol MG, correctly predicts the base peak in the mass spectra for 65 out of 75 cases. The correct base peak was calculated for three out of five targeted natural products. Ab initio ; Mass spectrometry ; Molecule ; Bond energy ; Ab initio quantum chemistry methods ; Bond length ; Bond order ; Mass spectrum Mass Spectrometry Techniques and Applications ; Computational Drug Discovery Methods ; Metabolomics and Mass Spectrometry Studies