jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Thomas Sayer | Yusef Farah | Rachelle Austin | Justin B. Sambur | Amber T. Krummel | Andrés Montoya−Castillo
Source: Nano Letters (article, 2023-06-13)
Field: Materials Science — Materials Chemistry

Trion Formation Resolves Observed Peak Shifts in the Optical Spectra of Transition-Metal Dichalcogenides Monolayer transition-metal dichalcogenides (ML-TMDs) have the potential to unlock novel photonic and chemical technologies if their optoelectronic properties can be understood and controlled. Yet, recent work has offered contradictory explanations for how TMD absorption spectra change with carrier concentration, fluence, and time. Here, we test our hypothesis that the large broadening and shifting of the strong band-edge features observed in optical spectra arise from the formation of negative trions. We do this by fitting an <i>ab initio</i> based, many-body model to our experimental electrochemical data. Our approach provides an excellent, global description of the potential-dependent linear absorption data. We further leverage our model to demonstrate that trion formation explains the nonmonotonic potential dependence of the transient absorption spectra, including through photoinduced derivative line shapes for the trion peak. Our results motivate the continued development of theoretical methods to describe cutting-edge experiments in a physically transparent way. Trion ; Spectral line ; Monolayer ; Materials science ; Photonics ; Molecular physics ; Absorption spectroscopy ; Absorption (acoustics) ; Transition metal ; Chemistry ; Condensed matter physics ; Chemical physics ; Optoelectronics ; Nanotechnology ; Physics ; Optics 2D Materials and Applications ; Perovskite Materials and Applications ; Graphene research and applications
Authors: Israa R. Shareef | Hiba K. Hussein | Basma L. Mahdi
Source: Advances in Science and Technology – Research Journal (article, 2023-11-21)
Field: Materials Science — Materials Chemistry

Experimental Investigation and Fuzzy Based Prediction of Titanium Alloy Performance During Drilling Process Recently, titanium and its alloys have been widely used in industry. Titanium alloys are difficult to machine due to high tool wear, cutting temperature, and edge formation. Thus, this analysis predicts how machining parameters, particularly drilling parameters, affect titanium work piece integrity. This study used Taguchi and fuzzy control software to calculate the effects of cutting parameters and drill tip angle on surface roughness maximal temperature in titanium alloy workpieces during dry drilling. Three 10 mm cutting tools have 106°, 118°, and 130° tip angles. Cutting tools are made of high-speed steel. The work piece model is a parallelogram with 100mm width, 150mm length, and 30mm thickness. Cutting settings include three spindle speeds. (500, 1000, and 1500) rpm with 0.1, 0.2, and 0.3 mm/rev feed rates. All simulations have the same hole depth (4 mm). We also estimated and discussed the rate of temperature change due to cutting settings. This prediction is used to diagnose and improve drilling, increase tool life, and safeguard the work piece. This reduces titanium drilling costs and effort. The machining model's work piece temperature is influenced by spindle speed and tool tip angle, but feed rate has no effect. Drillers can optimise drilling performance and obtain desired results including efficient penetration rates, shortened drilling time, and reduced equipment failure by regulating these parameters. Fuzzy Logic predicts drilling parameters on Titanium workpieces with encouraging results Materials science ; Drilling ; Titanium alloy ; Process (computing) ; Alloy ; Fuzzy logic ; Metallurgy ; Computer science ; Artificial intelligence Titanium Alloys Microstructure and Properties ; Hydrogen embrittlement and corrosion behaviors in metals ; Welding Techniques and Residual Stresses
Authors: Yingbing Liang | Shigesaburo Ogawa | Hiroshi Inaba | Kazunori Matsuura
Source: Frontiers in Molecular Biosciences (article, 2023-03-30)
Field: Materials Science — Materials Chemistry

Dramatic morphological changes in liposomes induced by peptide nanofibers reversibly polymerized and depolymerized by the photoisomerization of spiropyran Cytoskeletons such as microtubules and actin filaments are natural protein assemblies, which dynamically control cellular morphology by reversible polymerization/depolymerization. Recently, the control of polymerization/depolymerization of fibrous protein/peptide assemblies by external stimuli has attracted significant attention. However, as far as we know, the creation of an "artificial cytoskeleton" that reversibly controls the polymerization/depolymerization of peptide nanofiber in giant unilamellar vesicles (GUVs) has not been reported. Here, we developed peptide nanofiber self-assembled from spiropyran (SP)-modified <i>β</i>-sheet-forming peptides, which can be reversibly polymerized/depolymerized by light. The reversible photoisomerization of the SP-modified peptide (FKFEC<sup>SP</sup>KFE) to the merocyanine-peptide (FKFEC<sup>MC</sup>KFE) by ultraviolet (UV) and visible light irradiation was confirmed by UV-visible spectroscopy. Confocal laser scanning microscopy with thioflavin T staining and transmission electron microscopy of the peptides showed that the SP-peptide formed <i>β</i>-sheet nanofibers, whereas the photoisomerization to the merocyanine-peptide almost completely dissociated the nanofibers. The merocyanine peptide was encapsulated in spherical GUVs comprising of phospholipids as artificial cell models. Interestingly, the morphology of GUV encapsulating the merocyanine-peptide dramatically changed into worm-like vesicles by the photoisomerization to the SP-modified peptide, and then reversibly changed into spherical GUV by the photoisomerization to the MC-modified peptide. These dynamic morphological changes in GUVs by light can be applied as components of a molecular robot with artificially controlled cellular functions. Photoisomerization ; Merocyanine ; Biophysics ; Spiropyran ; Vesicle ; Peptide ; Depolymerization ; Polymerization ; Nanofiber ; Chemistry ; Photochemistry ; Materials science ; Nanotechnology ; Polymer chemistry ; Biochemistry ; Membrane ; Photochromism ; Organic chemistry ; Biology ; Polymer ; Isomerization Photochromic and Fluorescence Chemistry ; Supramolecular Self-Assembly in Materials ; Photoreceptor and optogenetics research
Authors: Nancy D’Arminio | Valentina Ruggiero | Giovanni Pierri | Anna Marabotti | Consiglia Tedesco
Source: Protein Science (article, 2023-12-15)
Field: Chemistry — Physical and Theoretical Chemistry

Emerging role of carbonyl–carbonyl interactions in the classification of beta turns Carbonyl-carbonyl interactions in peptides and proteins attracted considerable interest in recent years. Here, we report a survey of carbonyl-carbonyl interactions in cyclic peptides, depsipeptides, peptoids and discuss the relationship between backbone torsion angles and CO∙∙∙CO distances. In general, φ values in the range between -40° and -90° and between 40° and 90° correspond to CO∙∙∙CO distances below 3.22 Å. By extending the analysis of carbonyl-carbonyl interactions in different types of beta turns in proteins, we also highlight the role of direct or reciprocal carbonyl-carbonyl interactions in stabilizing the beta turn conformation for each specific type. We confirmed the new type II beta turn, detected by Dunbrack and coworkers, and named Pa, and detect the presence of a direct carbonyl-carbonyl interaction between the second and third residues of the turn. We also evidenced the existence of another new type II beta turn, named pA (following Dunbrack's notation), which represents the alternative conformation of Pa with opposite φ and ψ values and is characterized by a direct carbonyl-carbonyl interaction between the second and third residues of the turn. Finally, we show that the occurrence of CO∙∙∙CO interactions could be also advocated to explain from a chemical point of view the diversity of turn types. Carbonyl group ; Metal carbonyl ; BETA (programming language) ; Chemistry ; Stereochemistry ; Organic chemistry ; Computer science Crystallography and molecular interactions ; Protein Structure and Dynamics ; Computational Drug Discovery Methods
Authors: Katherine M. Collins | Nicola J. Evans | James H. Torpey | Jonathan M. Harris | Bethany A. Haynes | Amy H. Camp | Rivka L. Isaacson
Source: Microorganisms (article, 2023-04-20)
Field: Materials Science — Materials Chemistry

Structural Analysis of Bacillus subtilis Sigma Factors Bacteria use an array of sigma factors to regulate gene expression during different stages of their life cycles. Full-length, atomic-level structures of sigma factors have been challenging to obtain experimentally as a result of their many regions of intrinsic disorder. AlphaFold has now supplied plausible full-length models for most sigma factors. Here we discuss the current understanding of the structures and functions of sigma factors in the model organism, <i>Bacillus subtilis</i>, and present an X-ray crystal structure of a region of <i>B. subtilis</i> SigE, a sigma factor that plays a critical role in the developmental process of spore formation. Bacillus subtilis ; Sigma factor ; Sigma ; Six Sigma ; Biology ; Computational biology ; Spore ; Gene ; Physics ; Genetics ; Bacteria ; Gene expression ; Microbiology ; Chemistry ; Quantum mechanics ; Promoter Enzyme Structure and Function ; Bacterial Genetics and Biotechnology ; Bacteriophages and microbial interactions
Authors: Sanghyeok Yu | Young‐Soo Kim | Eunso Shin | Soon-Hong Kwon
Source: Micromachines (article, 2023-03-23)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Dynamic Beam Steering and Focusing Graphene Metasurface Mirror Based on Fermi Energy Control Beam steering technology is crucial for radio frequency and infrared telecommunication signal processing. Microelectromechanical systems (MEMS) are typically used for beam steering in infrared optics-based fields but have slow operational speeds. An alternative solution is to use tunable metasurfaces. Since graphene has gate-tunable optical properties, it is widely used in electrically tunable optical devices due to ultrathin physical thickness. We propose a tunable metasurface structure using graphene in a metal gap structure that can exhibit a fast-operating speed through bias control. The proposed structure can change beam steering and can focus immediately by controlling the Fermi energy distribution on the metasurface, thus overcoming the limitations of MEMS. The operation is numerically demonstrated through finite element method simulations. Beam steering ; Graphene ; Microelectromechanical systems ; Beam (structure) ; Materials science ; Optoelectronics ; Fermi energy ; Optical switch ; Optics ; Physics ; Nanotechnology Metamaterials and Metasurfaces Applications ; Plasmonic and Surface Plasmon Research ; Advanced Antenna and Metasurface Technologies
Authors: Manuel Katzer | Malte Selig | Dominik Christiansen | Mariana V. Ballottin | Peter C. M. Christianen | Andreas Knorr
Source: Physical Review Letters (article, 2023-10-02)
Field: Materials Science — Materials Chemistry

Impact of Optically Pumped Nonequilibrium Steady States on Luminescence Emission of Atomically Thin Semiconductor Excitons The interplay of the nonequivalent corners in the Brillouin zone of transition metal dichalcogenides (TMDCs) has been investigated extensively. While experimental and theoretical works contributed to a detailed understanding of the relaxation of selective optical excitations and the related relaxation rates, only limited microscopic descriptions of stationary experiments are available so far. Here we present microscopic calculations for the nonequilibrium steady state properties of excitons during continuous wave pumping exemplary for monolayer ${\mathrm{MoSe}}_{2}$. We find sharp features in photoluminescence excitation spectra and degree of polarization which result from phonon assisted excitonic transitions dominating over exciton recombination and intervalley exchange coupling. Exciton ; Photoluminescence ; Condensed matter physics ; Phonon ; Relaxation (psychology) ; Semiconductor ; Luminescence ; Materials science ; Excitation ; Brillouin zone ; Monolayer ; Polarization (electrochemistry) ; Non-equilibrium thermodynamics ; Atomic physics ; Physics ; Optoelectronics ; Nanotechnology ; Chemistry 2D Materials and Applications ; Perovskite Materials and Applications ; Luminescence and Fluorescent Materials
Authors: M. Magri | Pasquale Ciarletta
Source: Proceedings of the Royal Society A Mathematical Physical and Engineering Sciences (article, 2023-06-01)
Field: Materials Science — Polymers and Plastics

Mathematics meets the fashion industry on path to product innovation and sustainability Mathematics remains an endless source of inspiration for both the conception and the fabrication of clothes and fashion products. Over the last century, the prominent role of mathematics in the fashion industry has evolved together with the progress in computational resources and fabrication technologies. Nowadays, mathematics not only provides useful theoretical and computational tools to assist design and fabrication, but also acts as a catalyst of creativeness. This survey discusses the latest advances on mathematical models and methods in the fashion industry, restricting our attention to clothing design and multi-scale modelling, and their applications for digital manufacturing of textiles and garments. Particular focus is given to the usage of mathematics to drive product innovation and to reduce the environmental impact of the fashion industry in order to meet the Sustainable Development Goals of the United Nations. Clothing ; Product (mathematics) ; Sustainability ; Fashion industry ; Clothing industry ; Focus (optics) ; Product design ; Scale (ratio) ; Order (exchange) ; Engineering ; New product development ; Path (computing) ; Manufacturing engineering ; Computer science ; Architectural engineering ; Business ; Marketing ; Mathematics ; Political science Textile materials and evaluations ; Additive Manufacturing and 3D Printing Technologies ; Fashion and Cultural Textiles
Authors: Timothy Páez-Watson | Mark C.M. van Loosdrecht | A. Wahl
Source: Water Research (article, 2023-12-16)
Field: Materials Science — Biomaterials

From metagenomes to metabolism: Systematically assessing the metabolic flux feasibilities for “Candidatus Accumulibacter” species during anaerobic substrate uptake With the rapid growing availability of metagenome assembled genomes (MAGs) and associated metabolic models, the identification of metabolic potential in individual community members has become possible. However, the field still lacks an unbiassed systematic evaluation of the generated metagenomic information to uncover not only metabolic potential, but also feasibilities of these models under specific environmental conditions. In this study, we present a systematic analysis of the metabolic potential in species of "Candidatus Accumulibacter", a group of polyphosphate-accumulating organisms (PAOs). We constructed a metabolic model of the central carbon metabolism and compared the metabolic potential among available MAGs for "Ca. Accumulibacter" species. By combining Elementary Flux Modes Analysis (EFMA) with max-min driving force (MDF) optimization, we obtained all possible flux distributions of the metabolic network and calculated their individual thermodynamic feasibility. Our findings reveal significant variations in the metabolic potential among "Ca. Accumulibacter" MAGs, particularly in the presence of anaplerotic reactions. EFMA revealed 700 unique flux distributions in the complete metabolic model that enable the anaerobic uptake of acetate and its conversion into polyhydroxyalkanoates (PHAs), a well-known phenotype of "Ca. Accumulibacter". However, thermodynamic constraints narrowed down this solution space to 146 models that were stoichiometrically and thermodynamically feasible (MDF > 0 kJ/mol), of which only 8 were strongly feasible (MDF > 7 kJ/mol). Notably, several novel flux distributions for the metabolic model were identified, suggesting putative, yet unreported, functions within the PAO communities. Overall, this work provides valuable insights into the metabolic variability among "Ca. Accumulibacter" species and redefines the anaerobic metabolic potential in the context of phosphate removal. More generally, the integrated workflow presented in this paper can be applied to any metabolic model obtained from a MAG generated from microbial communities to objectively narrow the expected phenotypes from community members. Metabolic network ; Metagenomics ; Flux balance analysis ; Flux (metallurgy) ; Metabolic flux analysis ; Metabolic pathway ; Candidatus ; Biology ; Anaerobic exercise ; Ecology ; Chemistry ; Metabolism ; Biochemistry ; Genome ; Gene biodegradable polymer synthesis and properties ; Microbial Metabolic Engineering and Bioproduction ; Enzyme Catalysis and Immobilization
Authors: Alvin Muhammad Savero | Jong Ho Kim | Byantara Darsan Purusatama | Denni Prasetia | Se Hwi Park | Doan Van Duong | Nam–Hun Kim
Source: Forests (article, 2023-03-02)
Field: Chemistry — Organic Chemistry

Characterization of Anatomical and Non-Anatomical Properties for the Identification of Six Commercial Wood Species from Vietnamese Plantation Forests This study investigated the anatomical and non-anatomical characteristics of six wood species, Acacia mangium, Acacia hybrid, Dillenia pentagyna, Anacardium occidentale, Hevea brasiliensis, and Melaleuca cajuputi, from a plantation in Vietnam. The anatomical characteristics and non-anatomical characteristics were observed following the International Association of Wood Anatomists (IAWA) list. All species showed diffuse porosity and non-septate fibers. Exclusively solitary vessels were only observed in M. cajuputi. Vestured pits were observed in A. mangium, A. hybrid, and M. cajuputi, and tyloses were found in A. occidentale and H. brasiliensis. We observed vasicentric axial parenchyma in A. mangium, A. hybrid, A. occidentale, and H. brasiliensis, whereas diffuse axial parenchyma was observed in D. pentagyna and M. cajuputi. Further, prismatic crystals in the axial parenchyma cells existed in A. mangium, A. hybrid, and H. brasiliensis, and raphides in ray cells were observed in D. pentagyna. Silica bodies in ray cells were found in A. occidentale and M. cajuputi. H. brasiliensis exhibited the greatest vessel diameter and ray height, with D. pentagyna exhibiting the greatest fiber length and wall thickness. All the species showed considerable differences in heartwood fluorescence, water and ethanol extract colors, and froth test reactions. Parenchyma ; Acacia mangium ; Biology ; Botany ; Acacia ; Tracheid ; Hevea brasiliensis ; Xylem ; Materials science ; Composite material Wood and Agarwood Research ; Forest ecology and management ; Plant Pathogens and Fungal Diseases
Authors: Kalaiselvi Aramugam | Hazlee Azil Illias | Yern Chee Ching | Mohd Syukri Ali | Mohamad Zul Hilmey Makmud
Source: Energies (article, 2023-01-09)
Field: Materials Science — Materials Chemistry

Optimal Design of Corona Ring for 132 kV Insulator at High Voltage Transmission Lines Based on Optimisation Techniques The installation of a corona ring on an insulator string on a transmission line is one of the solutions to reduce the electric field stress surrounding the energised end of the insulator string. However, installing a corona ring with an optimum design to reduce the electric field magnitude on an insulator string is a challenging task. Therefore, in this work, a method to achieve the optimum design of a corona ring for 132 kV composite non-ceramic insulator string was proposed using two optimisation methods: the Imperialist Competitive Algorithm (ICA) and Grey Wolf Optimisation (GWO). A composite non-ceramic insulator string geometry with and without a corona ring was modelled in finite element analysis and used to obtain the electric field distribution in the model geometry. The electric field distribution was evaluated using a variation in the corona ring’s dimensions, i.e., the ring diameter, the ring tube diameter and the vertical position of the ring along the insulator string. From the results achieved, a comparison of the minimum electric field magnitude along the insulator string with a corona ring design shows that the minimum electric field magnitude is found to be lower using optimisation techniques compared to without using optimisation techniques by between 3.724% and 3.827%. Hence, this indicates the capability and effectiveness of the proposed methods in achieving the optimum design of a corona ring on an insulator string. Insulator (electricity) ; Corona ring ; Electric field ; Voltage ; Transmission line ; Corona (planetary geology) ; Corona discharge ; Electric power transmission ; High voltage ; Finite element method ; Electrical engineering ; Materials science ; Physics ; Engineering ; Structural engineering High voltage insulation and dielectric phenomena ; Thermal Analysis in Power Transmission ; Aerosol Filtration and Electrostatic Precipitation
Authors: Xu Han | Ryo Nakayama | Takefumi Kimura | Ryota Shimizu | Yasunobu Ando | Shigeru Kobayashi | Nobuaki Yasuo | Masakazu Sekijima | Taro Hitosugi
Source: Science and Technology of Advanced Materials Methods (article, 2023-05-04)
Field: Materials Science — Materials Chemistry

Tuning Bayesian optimization for materials synthesis: simulating two- and three-dimensional cases Compared to the optimization of a 1D synthesis parameter in materials synthesis, the optimization of multi-dimensional synthesis parameters is challenging for researchers. Bayesian optimization (BO) has shown high performance in optimizing high-dimensional synthesis parameters when appropriate hyperparameters are adopted. However, hyperparameter tuning for the kernel and acquisition functions used in BO is yet to be fully discussed by material researchers. In this study, we simulated materials synthesis under 2D and 3D synthesis conditions using artificial model functions with different process windows to investigate the effects of hyperparameters. The assumed parameters were temperature, oxygen partial pressure, and the sputtering power for thin-film deposition. Our findings indicate that estimating the process window and the range of physical property change based on the experience and knowledge of the materials researcher is crucial for tuning the hyperparameters of the kernel function. The simulations for high-dimensional search spaces case also indicate that the number of trials for optimization of synthesis conditions might reach several hundred or more. Therefore, the dimensionality and range of the search space must be limited based on the number of practical experiments, which is crucial for applying Bayesian optimization to materials synthesis. Our results facilitate fully automated and autonomous materials synthesis using BO and robotics for materials exploration in a high-dimensional search space. Bayesian optimization ; Bayesian probability ; Computer science ; Mathematical optimization ; Materials science ; Artificial intelligence ; Mathematics Machine Learning in Materials Science ; Manufacturing Process and Optimization ; Catalysis and Oxidation Reactions
Authors: Sterling G. Baird | Jason R. Hall | Taylor D. Sparks
Source: Computational Materials Science (article, 2023-03-30)
Field: Materials Science — Materials Chemistry

Compactness matters: Improving Bayesian optimization efficiency of materials formulations through invariant search spaces Degeneracy (biology) ; Curse of dimensionality ; Bayesian optimization ; Compact space ; Mathematical optimization ; Optimization problem ; Computer science ; Degenerate energy levels ; Mathematics ; Algorithm ; Physics ; Artificial intelligence Machine Learning in Materials Science ; Advanced Multi-Objective Optimization Algorithms ; Machine Learning and Data Classification