jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Mengting Chen | Lilusi Ma | Minxian Li | Xiaocui Fang | Yanlian Yang | Chen Wang
Source: ChemBioChem (article, 2024-12-13)
Field: Chemistry — Spectroscopy

Position‐Regulated Electrostatic Interactions for Single Amino Acid Revealed by Aspartic Acid‐Scanning Mutagenesis We have examined in this contribution the electrostatic interactions between single arginine and aspartic acid by analyzing the peptide-peptide binding characteristics involving arginine-aspartic acid, arginine-glycine, arginine-tryptophan and tryptophan-glycine interactions. The results of aspartic acid mutagenesis revealed that the interactions between arginine and aspartic acid have significant dependence on the position and composition of amino acids. While the primary interaction can be attributed to arginine-tryptophan contacts originated from the indole moieties with the main chains of 14-mers containing N-H and C=O moieties, pronounced enhancement could be identified in association with the electrostatic side-chain-side-chain interactions between arginine and aspartic acid. An optimal separation of 2~4 amino acids between two adjacent aspartic acid and tryptophan binding sites can be identified to achieve maximal enhancement of binding interactions. Such observed separation dependence may be utilized to unravel cooperative effects in heterogeneous interactions between single pair of amino acids. Aspartic acid ; Mutagenesis ; Amino acid ; Position (finance) ; Chemistry ; Amino acid residue ; Biochemistry ; Biophysics ; Mutation ; Biology ; Peptide sequence ; Gene Mass Spectrometry Techniques and Applications ; Analytical Chemistry and Chromatography ; Microfluidic and Capillary Electrophoresis Applications
Authors: Sarah Sanz Alonso | Yves Patrick Botchak Mouafi | Gabriel Micard | Giso Hahn | Barbara Terheiden
Source: SiliconPV Conference Proceedings (article, 2024-02-27)
Field: Materials Science — Materials Chemistry

Influence of Different Post Porosification Cleaning Steps on the Parameters of Porous Silicon Layer Stack To grow a defect-free epitaxial silicon wafer (EpiWafer) on a reorganized porous silicon layer stack, the surface must be closed, smooth and particle-free. A post-porosification cleaning step prior to reorganization should significantly reduce the density of (metallic) particles on the surface. In this paper we systematically investigate the influence of different post-porosification cleaning steps on the porous layer stack. The different cleaning steps have no significant effect on the layer thicknesses. On the other hand, the porosities change after the different cleaning steps. The change in porosity correlates very well with the oxidizing effect of the solution used: SC-1 cleaning has the strongest oxidizing effect, followed by ozone cleaning, piranha cleaning and HCl cleaning. A single HF dip has the smallest effect on porosity, showing the small influence of the native silicon oxide layer formed by aging on porosity. Except for the SC-1 cleaning, the other cleanings show no significant change in the Raman peak shift and therefore in stress compared to the as-etched sample. For the SC-1 cleaning, the increase in Raman peak shift and thus stress correlates well with the increase in porosity. After a reorganization step at 1120°C, it is observed that a higher porosity of the low porosity layer in the stack leads to larger pores. Stack (abstract data type) ; Layer (electronics) ; Materials science ; Silicon ; Porous silicon ; Porosity ; Environmental science ; Optoelectronics ; Nanotechnology ; Computer science ; Composite material ; Operating system Silicon Nanostructures and Photoluminescence ; Nanowire Synthesis and Applications ; Silicon and Solar Cell Technologies
Authors: Miyamoto, Yuki | Hiramoto, Ayami | Iwakuni, Kana | Kuma, Susumu | Enomoto, Katsunari | Nakayama, Naofumi | Baba, Masaaki
Source: Okayama University Scientific Achievement Repository (Okayama University) (article, 2024-04-09)
Field: Materials Science — Materials Chemistry

Analysis on high-resolution spectrum of the S1–S0 transition of free-base phthalocyanine A high-resolution absorption spectrum of the S-1-S-0 transition of free-base phthalocyanine was observed and analyzed with improved reliability. The spectrum, with a partially resolved rotational structure, was obtained by using the buffer-gas cooling technique and a single-mode tunable laser. Our new analysis reveals that the S-1 <- S-0 0(0)(0) band belongs to the a-type transition, where the electronic transition moment aligns parallel to the NH-HN direction, allowing the assignment of the S-1 state to B-1(3u). These results agree with a prior study using supersonic expansion and are well supported by theoretical calculations. Interestingly, the rotational constant B in the S-1 state, which is often smaller than that in the ground state for typical molecules, was found to be slightly larger than that in the S-0 (1)A(g) state. This suggests a change in the character of pi bonds with the electronic excitation. Ground state ; Molecular electronic transition ; Phthalocyanine ; Atomic electron transition ; Transition dipole moment ; Supersonic speed ; Absorption spectroscopy ; Moment (physics) ; Electronic structure Porphyrin and Phthalocyanine Chemistry ; Molecular Spectroscopy and Structure ; Photochemistry and Electron Transfer Studies
Authors: Zhongyuan Liu | Ruotian Gong | Benchen Huang | Yu Jin | Xinyi Du | Guanghui He | Eli Janzen | Yang Li | Erik Henriksen | James H. Edgar | Giulia Galli | Chong Zu
Source: arXiv (Cornell University) (preprint, 2024-04-23)
Field: Materials Science — Materials Chemistry

Temperature dependent spin-phonon coupling of boron-vacancy centers in hexagonal boron nitride The negatively charged boron-vacancy center ($\mathrm{V}_{\mathrm{B}}^-$) in hexagonal boron nitride (hBN) has recently emerged as a highly promising quantum sensor. Compared to the nitrogen-vacancy (NV) center in diamond, the change with temperature of the spin transition energy of $\mathrm{V}_{\mathrm{B}}^-$ is more than an order of magnitude larger, making it a potential nanoscale thermometer with superior sensitivity. However, the underlying mechanism of the observed large temperature dependence remains an open question. In this work, using isotopically purified $\mathrm{h}{}^{10}\mathrm{B}{}^{15}\mathrm{N}$, we systematically characterize the zero-field splitting, hyperfine interaction, and spin relaxation time of $\mathrm{V}_{\mathrm{B}}^-$ from 10 to 350$~$K. We carry out first-principle calculations of the $\mathrm{V}_{\mathrm{B}}^-$ spin-phonon interaction and show that a second-order effect from finite-temperature phonon excitations is responsible for the observed changes in experiments. By fitting our experimental results to a physically motivated model, we extract the dominant phonon mode which agrees well with our simulations. Finally, we investigate the dynamic nuclear spin polarization process at cryogenic temperatures. Our results provide key insights in $\mathrm{V}_{\mathrm{B}}^-$ centers and their utilization as nanoscale thermometers and phonon sensors. Hexagonal boron nitride ; Vacancy defect ; Boron ; Phonon ; Condensed matter physics ; Materials science ; Coupling (piping) ; Hexagonal crystal system ; Boron nitride ; Spin (aerodynamics) ; Crystallography ; Physics ; Nanotechnology ; Chemistry ; Metallurgy ; Nuclear physics ; Thermodynamics ; Graphene Boron and Carbon Nanomaterials Research ; Diamond and Carbon-based Materials Research ; Graphene research and applications
Authors: Dezhi Song | Fuyang Huang | Gang Yao | Haimin Zhang | Haiming Huang | Hang Yan | Jun Zhang | Qinghua Zhang | Lin Gu | Xucun Ma | Jinfeng Jia | Qi‐Kun Xue | Ye-Ping Jiang
Source: arXiv (Cornell University) (preprint, 2024-12-08)
Field: Materials Science — Electronic, Optical and Magnetic Materials

The re-entrant ferromagnetism due to symmetric exchange bias in two septuple-layer MnBi2Te4 epitaxial films MnBi2Te4 (MBT) is a typical magnetic topological insulator with an A-type antiferromagnetic (AFM) ground state. Here we prepared ultra-thin MBT films with controlled anti-site defects and observed rich doping-dependent magnetic behaviors. We find in one-septuple-layer MBT films a ferrimagnetic ground state and in two-septuple-layer ones a kind of re-entrant ferromagnetism (FM) that disappears with increased Bi-on-Mn doping in the FM Mn-layers. This re-entrant behavior is attributed to a kind of symmetric exchange-bias effect that arises in the presence of both AFM and FM sub-systems due to the introduction of high-dense Mn-on-Bi anti-site defects. Furthermore, all MBT films display spin-glass-like behaviors. Our work demonstrates rich magnetic behaviors originating from the competing magnetic interactions between Mn spins at different lattice positions in MBT. Ferromagnetism ; Condensed matter physics ; Exchange bias ; Epitaxy ; Layer (electronics) ; Materials science ; Nanotechnology ; Physics ; Magnetization ; Quantum mechanics ; Magnetic anisotropy ; Magnetic field Magnetic and transport properties of perovskites and related materials ; Magnetic properties of thin films ; Heusler alloys: electronic and magnetic properties
Authors: Gregory M Core
Source: OSTI OAI (U.S. Department of Energy Office of Scientific and Technical Information) (article, 2024-05-24)
Field: Materials Science — Materials Chemistry

ENYGF 2023 - Design of Temperature-controlled Fuel-salt Irradiation Experiment Idaho National Laboratory (INL) is developing a Molten salt Research Temperature-controlled Irradiation (MRTI) experimental capsule for the Neutron Radiography (NRAD) reactor. The experiment is envisaged to be versatile and able to host a variety of salt-wall material combinations. The first test is designed to contain actinide-bearing chloride salt, which previously has not been subjected to a neutron field. The main objectives of the experiment are to produce irradiated salt samples for Post Irradiation Examination (PIE), to evaluate salt behavior under irradiation, and to test in-situ sensors/instrumentation. The final design for the experiment completed in 2022, and fabrication of the experiment is underway. The salt is double encapsulated providing insulation and redundancy in the case of leakage. A gas-gap between the inner capsule and the outer container enables tuning of thermal conduction to the NRAD coolant by altering its thickness and its gas-mixture. An inert gas mixture ratio in the gas-gap ensures the configurations reached a targeted average salt temperature of 600oC, while avoiding salt freezing or exceeding material limits. A resistive heater placed within a thermowell and controls the temperature of the experiment (both when the reactor is on or off). The selected configurations can contain over 10 cm3 of fuel-bearing chloride salt, which is sufficient for the purposes of the post-irradiation examination (PIE) and provides sufficient volume for two submerged thermocouple probes to monitor salt temperature. The capsule wall material is Inconel 625, and weld qualifications for the assembly have been developed. A glove-box laser weld technique was refined as part of this process to ensure a leak-tight assembly for the salt-bearing assembly and reduce the risks of impurities permeating into the salt. This work was supported through the INL Laboratory Directed Research & Development (LDRD) Program under DOE Idaho Operations Office Contract DE-AC07-05ID14517. Irradiation ; Salt (chemistry) ; Environmental science ; Waste management ; Nuclear engineering ; Chemistry ; Engineering ; Physics ; Nuclear physics ; Organic chemistry Nuclear Materials and Properties ; Nuclear reactor physics and engineering ; Nuclear Engineering Thermal-Hydraulics
Authors: Payal Saha | Purbajyoti Bhagowati | Munima B. Sahariah
Source: AIP conference proceedings (article, 2024-01-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Effect of spin-orbit coupling on Mn1.5PtSn For spintronics applications, the materials which have high spin-polarization at the Fermi level are prospective materials. In this study, we investigated how spin-orbit coupling affected the electronic and magnetic characteristics of Mn1.5PtSn, an inverse tetragonal Heusler compound exhibiting both ferromagnetic and ferrimagnetic spin orders. By employing density functional theory calculations, we determined that at the ground state the ferrimagnetic configuration is more stable than the ferromagnetic one, in spite of the spin-orbit coupling. To validate our findings, we analyzed the density of states and band structure plots for the compound. Our results suggest that precise modification of the constituent atoms could transform this compound into a half-metallic material appropriate for spin-transfer-torque-based technology. Orbit (dynamics) ; Coupling (piping) ; Spin–orbit interaction ; Spin (aerodynamics) ; Computer science ; Astrobiology ; Physics ; Materials science ; Condensed matter physics ; Aerospace engineering ; Engineering ; Composite material Heusler alloys: electronic and magnetic properties ; ZnO doping and properties ; Metal and Thin Film Mechanics
Authors: Cheryl LaRose | Lisa Denomie | Wiikwedong ECD Collaborative
Source: American Indian Culture and Research Journal (article, 2024-05-08)
Field: Chemistry — Organic Chemistry

Niwiidosendimin (We Walk with Each Other) Five rivers flow into Gichigami (Lake Superior). Reflecting their surroundings, five early childhood education leaders in the Keweenaw Bay Indian Community have come together to strengthen early childhood teaching and systems of care and learning across four programs in the community. We are the Wiikwedong Early Childhood Development Collaborative, and this is our story of how we implemented Community-Based Inquiry to collaborate, share information and insights, and work with each other to create stronger early learning opportunities in our community. History ; Sociology Synthesis and Catalytic Reactions ; Click Chemistry and Applications ; Chemical Synthesis and Analysis
Authors: Ke Xu | Qiaolin Yang | Wenhao Liu | Rong Zhang | Zhi Wang | Jiandong Ye
Source: arXiv (Cornell University) (preprint, 2024-08-16)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Tailoring light holes in $β$-$Ga_{2}O_{3}$ via Anion-Anion Antibonding Coupling A significant limitation of wide-bandgap materials is their low hole mobility related to localized holes with heavy effective masses ($m_h^*$). We identify in low-symmetric wide-bandgap compounds an anion-anion antibonding coupling (AAAC) effect as the intrinsic factor behind hole localization, which explains the extremely heavy $m_h^*$ and self-trapped hole (STH) formation observed in gallium oxide ($β$-$Ga_{2}O_{3}$). We propose a design principle for achieving light holes by manipulating AAAC, demonstrating that specific strain conditions can reduce $m_h^*$ in $β$-$Ga_{2}O_{3}$ from 4.77 $m_0$ to 0.38 $m_0$, making it comparable to the electron mass (0.28 $m_0$), while also slightly suppresses the formation of self-trapped holes, evidenced by the reduction in the formation energy of hole polarons from -0.57 eV to -0.45 eV under tensile strain. The light holes show significant anisotropy, potentially enabling two-dimensional transport in bulk material. This study provides a fundamental understanding of hole mass enhancement and STH formation in novel wide-bandgap materials and suggest new pathways for engineering hole mobilities. Ion ; Antibonding molecular orbital ; BETA (programming language) ; Coupling (piping) ; Physics ; Materials science ; Crystallography ; Chemistry ; Nuclear physics ; Electron ; Atomic orbital ; Computer science ; Metallurgy ; Quantum mechanics Ga2O3 and related materials ; Semiconductor materials and devices ; Electronic and Structural Properties of Oxides
Authors: Won‐Jae Lee | Vincent Liu | Zhelun Zhang | Seung‐Hyun Kim | Ruotian Gong | Xinyi Du | Khanh Pham | Thomas Poirier | Zeyu Hao | James H. Edgar | Philip Kim | Chong Zu | Emily J. Davis | Norman Y. Yao
Source: arXiv (Cornell University) (preprint, 2024-06-17)
Field: Materials Science — Materials Chemistry

Intrinsic high-fidelity spin polarization of charged vacancies in hexagonal boron nitride The negatively charged boron vacancy ($\mathrm{V}_{\mathrm{B}}^-$) in hexagonal boron nitride (hBN) has garnered significant attention among defects in two-dimensional materials. This owes, in part, to its deterministic generation, well-characterized atomic structure, and optical polarizability at room temperature. We investigate the latter through extensive measurements probing both the ground and excited state polarization dynamics. We develop a semiclassical model based on these measurements that predicts a near-unity degree of spin polarization, surpassing other solid-state spin defects under ambient conditions. Building upon our model, we include the presence of nuclear spin degrees of freedom adjacent to the $\mathrm{V}_{\mathrm{B}}^-$ and perform a comprehensive set of Lindbladian numerics to investigate the hyperfine-induced polarization of the nuclear spins. Our simulations predict a number of important features that emerge as a function of magnetic field which are borne out by experiment. Materials science ; Hexagonal boron nitride ; Boron nitride ; Condensed matter physics ; Nitride ; Polarization (electrochemistry) ; Boron ; Hexagonal crystal system ; Spin polarization ; Crystallography ; Nanotechnology ; Physics ; Chemistry ; Nuclear physics ; Physical chemistry ; Graphene Diamond and Carbon-based Materials Research ; Semiconductor materials and devices ; Graphene research and applications
Authors: Fernando Generoso Neiva Ferreira | Eduardo Alves Machado | Fabiano Almir Barbosa | Ivan Augusto Martins | Juliano Braz Possati | Marcelo Urdapilleta Rodrigues | Maurício Franco Bomfim | Odair Kirmse | Sérgio Augusto Barbosa da Silva | Thomas Frank
Source: Tecnologia em Metalurgia Materiais e Mineração (article, 2024-01-01)
Field: Materials Science — Materials Chemistry

Development of Cr-alloyed high carbon sheet steel - BW AC C77MD - for the manufacture of clutch bearing rings by deep drawing Clutch bearing rings are high-performance parts that require excellent cleanliness and microstructure homogeneity to meet their wear and fatigue requirements.To improve productivity and reduce costs, a modified Cr alloyed steel with high carbon content has been developed by bearing manufacturers in cooperation with steel producers, which is well suited in terms of formability and is widely used in the production of automotive components, where it is purchased in the form of the cold-rolled strip for forming.This work investigated the process parameters and critical characteristics for developing Cr-alloyed sheet steel with high carbon content to produce clutch bearing rings on an industrial scale.Tensile test, hardness test, optical microscopy (OM), and scanning electron microscopy (SEM) were used to evaluate the mechanical and metallurgical properties of the studied steel throughout the process (casting, hot rolling, cold rolling + batch annealing, and heat treatment).The results have shown that it is possible to tune the mechanical properties of highcarbon steel at each stage of the process by using the proper heat and metallurgical treatment targeted at the requirements of the final application. Clutch ; Bearing (navigation) ; Metallurgy ; Materials science ; High carbon ; Carbon fibers ; Carbon steel ; Deep drawing ; Composite material ; Engineering ; Mechanical engineering ; Computer science ; Corrosion Metal Alloys Wear and Properties ; Metallurgy and Material Forming ; Microstructure and Mechanical Properties of Steels
Authors: Hamed Tidjani Tabe Gbian | Edem Chabi | Valéry Doko | Kora Farid Carlos Yarou | Emmanuel Olodo
Source: Open Journal of Applied Sciences (article, 2024-01-01)
Field: Materials Science — Polymers and Plastics

Development and Characterization of Particle Boards Based on Sorghum Husk This study tackles current environmental challenges by developing innovative and eco-friendly particle boards utilizing sorghum husk, combined with recycled expanded polystyrene (EPS). This dual eco-responsible approach valorizes sorghum husk, often deemed agricultural waste, and repurposes EPS, a plastic waste, thus contributing to CO2 emission reduction and effective waste management. The manufacturing process involves dissolving recycled polystyrene within a solvent to create a binder, which is then mixed with sorghum husk and cold-pressed into composite boards. The study explores the impact of two particle sizes (fine and coarse) and two different concentrations of the recycled EPS binder. Results demonstrate significant variations in the boards’ mechanical properties, displaying a range of Modulus of Rupture (MOR) from 0.84 MPa to 3.85 MPa, and Modulus of Elasticity (MOE) spanning from 658.13 MPa to 1313.25 MPa, influenced by the binder concentration and particle size. These characteristics suggest that the boards can be effectively used in various construction applications, including interior decoration, false ceilings, and potentially for furniture and door manufacturing when combined with appropriate coatings. This study not only exemplifies the valorization of plastic and agricultural wastes but also offers a practical, localized solution to global climate change challenges by promoting sustainable construction materials. Husk ; Sorghum ; Characterization (materials science) ; Particle (ecology) ; Mathematics ; Materials science ; Agronomy ; Botany ; Nanotechnology ; Biology Natural Fiber Reinforced Composites ; Lignin and Wood Chemistry
Authors: Detlef‐M. Smilgies | Ruipeng Li
Source: ChemRxiv (preprint, 2024-12-11)
Field: Chemistry — Organic Chemistry

indexGIXS – software for visualizing and interactive indexing of grazing-incidence scattering data Grazing incidence small- and wide-angle scattering (GISAXS, GIWAXS) are widely applied for the study of organic thin films, be it for the characterization of nanostructured morphologies in block copolymers, nanocomposites, or nanoparticle assemblies, or the packing and orientation of small aromatic molecules and conjugated polymers. Organic thin films typically are uniaxial powders, with specific crystallographic planes oriented parallel to the substrate surface. The associated fiber texture scattering patterns are complicated by refraction corrections and multiple scattering. We present an interactive graphics tool to index such patterns. Grazing-incidence small-angle scattering ; Scattering ; Materials science ; Thin film ; Substrate (aquarium) ; Nanoporous ; Texture (cosmology) ; Optics ; Refraction ; Light scattering ; Biological small-angle scattering ; Small-angle neutron scattering ; Nanotechnology ; Computer science ; Neutron scattering ; Physics ; Image (mathematics) Advanced Polymer Synthesis and Characterization ; Machine Learning in Materials Science
Authors: Zhixin Sun | Xu Wang | XiaoJin He | ZhiWei Tan | Chunming Liu | Hang Zhou
Source: SID Symposium Digest of Technical Papers (article, 2024-04-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

P‐5.27: Outdoor 55‐Inch 4K‐resolution and High‐Brightness Liquid Crystal Display This work addresses the design and verification of an outdoor 55‐inch 4K‐resolution and high‐brightness liquid crystal display (LCD) product. The new pixel design is able to increase the module transmittance to as high as 6.24%. The amorphous silicon (a‐Si) thin film transistor (TFT) has excellent light‐ and temperature‐stability. The gate drive circuit has been improved to reduce the operating temperature by 5~7 â„ƒ. The brightness of the display is up to 4056 nits, which is the brightest known 55‐inch 4K‐resolution display product. Brightness ; Liquid-crystal display ; Resolution (logic) ; Computer graphics (images) ; Materials science ; Optics ; Liquid crystal ; Computer science ; Optoelectronics ; Physics ; Artificial intelligence Liquid Crystal Research Advancements ; Plant Reproductive Biology ; Photonic Crystals and Applications