jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Kang N. Lee | Bryan J. Harder | Bernadette J. Puleo | Amjad S. Almansour | James D. Kiser | John A. Setlock | Dennis S. Fox | Michael D. Cuy | Sreeramesh Kalluri | Ramakrishna T. Bhatt
Source: Coatings (article, 2022-10-28)
Field: Materials Science — Ceramics and Composites

Manufacturing Process Development and Rig Validation of Slurry Environmental Barrier Coatings for SiC Ceramic and SiC Composite Sub-Components The process scale-up of fully oxide-based environmental barrier coatings (EBCs) on sintered SiC and chemical vapor infiltration (CVI) SiC/SiC ceramic matrix composite (CMC) sub-components was investigated using various slurry manufacturing processes (dip, spray, spin–dip). The performance of EBC-coated sub-components (SiC heating element, SiC/SiC ceramic matrix mini-composite, SiC airfoil, SiC/SiC CMC airfoil) was evaluated in steam oxidation and combustion rigs. Steam oxidation was conducted at 1427 °C in 90 vol.% H2O (g) + 10 vol.% O2 (g) with a 1 h hold at 1427 °C per cycle (1 h hot and 20 min cooling). For high-pressure combustion rig testing, the EBC surface temperature ranged between 1354 °C and 1538 °C with the temperature gradient through CMC + EBC ranging between 100 °C and 150 °C. Dip and spin–dip are non-line-of-sight processes, whereas spray is a line-of-sight process. The three processes, collectively, demonstrated the capability to manufacture slurry EBCs on sub-components with various shapes and sizes. There was no discernable disparity in the EBC steam oxidation performance between the coupons and sub-components in this study and coupons in a previous study. The dependence of steam oxidation rates on the substrate chemistry reported previously was confirmed. The steam oxidation rate of EBC-coated sintered SiC, compared with EBC-coated CVI CMC, was ~2 times and ~1.5 times higher after 100 h and 500 h, respectively, due to the boron sintering aid in sintered SiC. An EBC-coated CMC airfoil after 150 15-h-long cycles in a high-pressure combustion rig test showed only limited EBC spallation along the leading edge and more substantial spallation along the trailing edge, demonstrating the feasibility of an oxide-based bond coat to meet the extreme temperature requirements of next-generation EBCs. Materials science ; Ceramic ; Sintering ; Composite number ; Slurry ; Ceramic matrix composite ; Composite material Advanced ceramic materials synthesis ; Advanced materials and composites ; High-Temperature Coating Behaviors
Authors: Raghuram Thyagarajan | David S. Sholl
Source: The Journal of Physical Chemistry C (article, 2022-05-06)
Field: Chemistry — Inorganic Chemistry

Molecular Simulations of CH<sub>4</sub> and CO<sub>2</sub> Diffusion in Rigid Nanoporous Amorphous Materials Molecular diffusion in nanoporous materials is important in determining the rate of equilibration of various adsorption processes and plays a pivotal role in kinetic separations and membrane-based separations. Because generating realistic structures of amorphous nanoporous materials is difficult, far less is known about diffusion in amorphous nanoporous materials than in their crystalline counterparts. Here, we present molecular dynamics simulations assessing the room-temperature self-diffusion of CH4 and CO2 in a wide range of rigid amorphous nanoporous materials, including porous carbons, kerogens, polymers of intrinsic microporosity, and hyper-cross-linked polymers. Our results are the largest collection of molecular diffusivities in amorphous nanoporous materials to date. In each material, the diffusivity increases with the adsorbate concentration at low and moderate adsorbate concentrations, reaching a maximum before decreasing due to steric effects at higher concentrations. The observed diffusivities are much slower than that would be expected based on standard descriptions of Knudsen diffusivity. We show that the observed diffusivities are not correlated in a simple way with scalar descriptors of the pore structures such as the pore limiting diameter. Nanoporous ; Amorphous solid ; Materials science ; Thermal diffusivity ; Diffusion ; Adsorption ; Molecular dynamics ; Porosity ; Polymer ; Chemical physics ; Chemical engineering ; Porous medium ; Knudsen diffusion ; Thermodynamics ; Nanotechnology ; Physical chemistry ; Chemistry ; Organic chemistry ; Computational chemistry ; Composite material ; Physics Metal-Organic Frameworks: Synthesis and Applications ; Membrane Separation and Gas Transport ; Zeolite Catalysis and Synthesis
Authors: Zhilian Yang | Tianhao Zhang | Jiarui Ren | Jiawen Li | Jianlong Ge | Haoru Shan | Tao Ji | Mingshen Xu | Qixia Liu
Source: RSC Advances (article, 2022-01-01)
Field: Chemistry — Organic Chemistry

Nano-silver functionalized spherical activated carbon with enhanced dipropyl sulfide adsorption capacity and antibacterial properties Owing to the large dynamic adsorption performance and excellent mechanical strength, spherical activated carbon (SAC) has been widely applied in the field of biochemical protection. However, the adsorbed chemical warfare agent molecules might easily escape from the pores of SAC due to the impact of ambient temperature and humidity, resulting in secondary pollution. Herein, to improve the adsorption performance of SAC, an excessive impregnation method was used to fabricate nano-silver functionalized spherical activated carbon (Ag-SAC). The surface physicochemical structure of the obtained Ag-SAC was extensively studied, and dipropyl sulfide (DPS), a simulant of sulfur mustard (HD), was employed as the adsorbate to evaluate its adsorption capability. The effects of AgNO<sub>3</sub> impregnation concentration, reaction time, initial concentration and temperature on the adsorption performance, were investigated. The equilibrium adsorption capacity of Ag-SAC towards DPS increased by 13.41% compared with that of pristine SAC. Kinetic models, adsorption isotherm models, and adsorption thermodynamics were used to study the adsorption mechanism. The results revealed that the adsorption of DPS by Ag-SAC is a mixed synergistic process, which includes chemical adsorption and physical adsorption. Moreover, the Ag-SAC exhibited good antibacterial characteristics, with an antibacterial rate over 99.28% against <i>Escherichia coli</i>. We anticipate that the Ag-SAC could be a promising material for the development of high performance breathable biochemical protection clothing. Adsorption ; Activated carbon ; Chemical engineering ; Composite number ; Sulfide ; Silver Nano ; Antibacterial activity ; Nanoparticle ; Materials science ; Carbon fibers ; Silver nanoparticle ; Nano- ; Chemistry ; Nanotechnology ; Organic chemistry ; Composite material ; Bacteria Nanomaterials for catalytic reactions ; Graphene and Nanomaterials Applications ; Adsorption and biosorption for pollutant removal
Authors: Laura Sierra | Carlos Gibaja | Íñigo Torres | Elena Salagre | Juan Ramón Avilés‐Moreno | E. G. Michel | P. Ocón | Félix Zamora
Source: Nanomaterials (article, 2022-10-26)
Field: Materials Science — Materials Chemistry

Alpha-Germanium Nanolayers for High-Performance Li-ion Batteries The exfoliation of tridimensional crystal structures has recently been considered a new source of bidimensional materials. The new approach offers the possibility of dramatically enlarging the library of bidimensional materials, but the number of nanolayers produced so far is still limited. Here, we report for the first time the use of a new type of material, α-germanium nanolayers (2D α-Ge). The 2D α-Ge is obtained by exfoliating crystals of α-germanium in a simple one-step procedure assisted by wet ball-milling (gram-scale fabrication). The α-germanium nanolayers have been tested as anode material for high-performance LIBs. The results show excellent performance in semi-cell configuration with a high specific capacity of 1630 mAh g<sup>-1</sup> for mass loading of 1 mg cm<sup>-2</sup> at 0.1 C. The semi-cell was characterized by a constant current rate of 0.5 C during 400 cycles and different scan rates (0.1 C, 0.5 C, and 1 C). Interestingly, the structural characterization, including Raman spectroscopy, XRPD, and XPS, concludes that 2D α-Ge largely retains its crystallinity after continuous cycling. These results can be used to potentially apply these novel 2D germanium nanolayers to high-performance Li-ion batteries. Germanium ; Materials science ; Crystallinity ; X-ray photoelectron spectroscopy ; Raman spectroscopy ; Anode ; Exfoliation joint ; Germanium oxide ; Chemical engineering ; Nanotechnology ; Fabrication ; Optoelectronics ; Composite material ; Optics ; Graphene ; Silicon ; Physical chemistry MXene and MAX Phase Materials ; Advancements in Battery Materials ; Graphene research and applications
Authors: Charles Manière | Christelle Harnois | Sylvain Marinel
Source: Journal of the European Ceramic Society (article, 2022-12-05)
Field: Materials Science — Ceramics and Composites

Role of microstructure reactivity and surface diffusion in explaining flash (ultra-rapid) sintering kinetics Sintering ; Materials science ; Microstructure ; Porosity ; Kinetics ; Diffusion ; Surface diffusion ; Particle (ecology) ; Composite material ; Flash (photography) ; Thermodynamics ; Adsorption ; Physical chemistry ; Chemistry ; Optics Advanced ceramic materials synthesis ; Advanced materials and composites ; Aluminum Alloys Composites Properties
Authors: Radu A. Talmazan | José Refugio Monroy | Federico del Río‐Portilla | Iván Castillo | Maren Podewitz
Source: ChemCatChem (article, 2022-07-23)
Field: Chemistry — Organic Chemistry

Encapsulation Enhances the Catalytic Activity of C‐N Coupling: Reaction Mechanism of a Cu(I)/Calix[8]arene Supramolecular Catalyst Development of C-N coupling methodologies based on Earth-abundant metals is a promising strategy in homogeneous catalysis for sustainable processes. However, such systems suffer from deactivation and low catalytic activity. We here report that encapsulation of Cu(I) within the phenanthroyl-containing calix[8]arene derivative 1,5-(2,9-dimethyl-1,10-phenanthroyl)-2,3,4,6,7,8-hexamethyl-<i>p</i>-tert-butylcalix[8]arene (<b>C<sub>8</sub>PhenMe<sub>6</sub></b> ) significantly enhances C-N coupling activity up to 92 % yield in the reaction of aryl halides and aryl amines, with low catalyst loadings (2.5 % mol). A tailored multiscale computational protocol based on Molecular Dynamics simulations and DFT investigations revealed an oxidative addition/reductive elimination process of the supramolecular catalyst [<b>Cu(C<sub>8</sub>PhenMe<sub>6</sub>)I</b>]. The computational investigations uncovered the origins of the enhanced catalytic activity over its molecular analogues: Catalyst deactivation through dimerization is prevented, and product release facilitated. Capturing the dynamic profile of the macrocycle and the impact of non-covalent interactions on reactivity allows for the rationalization of the behavior of the flexible supramolecular catalysts employed. Catalysis ; Supramolecular chemistry ; Encapsulation (networking) ; Chemistry ; Supramolecular catalysis ; Combinatorial chemistry ; Photochemistry ; Organic chemistry ; Molecule Catalytic Cross-Coupling Reactions ; Supramolecular Chemistry and Complexes ; Nanocluster Synthesis and Applications
Authors: Achyut Dahal | Mary Lo | Sitanshu S. Singh | Huu Vo | Denzel ElHage | Seetharama D. Jois | Siva Murru
Source: Chemical Biology & Drug Design (article, 2022-02-14)
Field: Chemistry — Organic Chemistry

1,3‐diarylpyrazolones as potential anticancer agents for non‐small cell lung cancer: Synthesis and antiproliferative activity evaluation A series of pyrazolone compounds with different substitution patterns have been synthesized using microwave-assisted methods and evaluated their in vitro antiproliferative activity against human lung adenocarcinoma cell lines (A549 and NCI-H522). Among the tested compounds, the pyrazolone P7 exhibited high antiproliferative activity against both A549 and NCIH522 cancer cell lines while being 10 times less cytotoxic to non-cancerous cells. Moreover, our compounds P7 and P11 exhibited higher antiproliferative activity and selectivity against A549 and NCIH522 cells compared with the clinically approved drugs Afatinib and Gefitinib. The cell cycle analysis showed that the compound P7 and P11 arrests the cell cycle at G0/G1 phase, whereas the compounds P13 and P14 involved in G2/M phase arrest. The results from antiproliferative activity screening, cell cycle analysis, and kinase profiling indicate that the suitably substituted 1,3-diarylpyrazolones exhibit high antiproliferative activity against non-small cell lung cancer cells. Pharmacology ; Chemistry ; Cancer research ; Computational biology ; Biology Synthesis and biological activity ; Synthesis and Biological Activity ; Synthesis and Biological Evaluation
Authors: Przemysław Zaręba | Paweł Śliwa | Grzegorz Satała | Paweł Zajdel | Gniewomir Latacz | Jolanta Jaśkowska
Source: European Journal of Medicinal Chemistry (article, 2022-03-26)
Field: Chemistry — Organic Chemistry

New N-aryl-N′-aryl-/(thio)ureido-/sulfamoylamino-derivatives of alkyl/alkylcarbamoyl piperazines: Effect of structural modifications on selectivity over 5-HT1A receptor The 5-HT<sub>1A</sub> receptors are an important biological target in the treatment of CNS diseases. Recently, their importance in the context of non-CNS disease entities has also been postulated. In the light of these reports, we designed a new group of urea derivatives of N-aryl-N'-aryl-/(thio)ureido-/sulfamoylamino-derivatives of alkyl/alkylcarbamoyl piperazines as 5-HT<sub>1A</sub>R ligands, focusing on increasing receptor selectivity. We made structural modifications in three areas of the molecule. In the course of our research, we obtained a ligand with reduced basicity (6f), which, despite the loss of the protonable nitrogen atom, did not lose its affinity for the 5-HT<sub>1A</sub>R (K<sub>i</sub> = 35 nM) with a simultaneous increase in selectivity. In particular, a decrease in affinity for D<sub>2</sub>R (K<sub>i</sub> = 1940 nM) was observed, which was analyzed using molecular modeling methods, including FMO and molecular dynamics. Basic ADME-Tox parameters were characterized for 6f, confirming its potential applicability in pharmacotherapy. Chemistry ; Selectivity ; Aryl ; Context (archaeology) ; ADME ; Thio- ; Alkyl ; Ligand (biochemistry) ; Stereochemistry ; Molecular model ; Chemical synthesis ; Receptor ; Organic chemistry ; Biochemistry ; In vitro Synthesis and Biological Evaluation ; Receptor Mechanisms and Signaling ; Chemical Reaction Mechanisms
Authors: Jacob M. Goldberg | Stephen J. Lippard
Source: FEBS Letters (review, 2022-11-23)
Field: Chemistry — Spectroscopy

Mobile zinc as a modulator of sensory perception Mobile zinc is an abundant transition metal ion in the central nervous system, with pools of divalent zinc accumulating in regions of the brain engaged in sensory perception and memory formation. Here, we present essential tools that we developed to interrogate the role(s) of mobile zinc in these processes. Most important are (a) fluorescent sensors that report the presence of mobile zinc and (b) fast, Zn-selective chelating agents for measuring zinc flux in animal tissue and live animals. The results of our studies, conducted in collaboration with neuroscientist experts, are presented for sensory organs involved in hearing, smell, vision, and learning and memory. A general principle emerging from these studies is that the function of mobile zinc in all cases appears to be downregulation of the amplitude of the response following overstimulation of the respective sensory organs. Possible consequences affecting human behavior are presented for future investigations in collaboration with interested behavioral scientists. Sensory system ; Zinc ; Perception ; Neuroscience ; Chemistry ; Communication ; Psychology Molecular Sensors and Ion Detection ; Trace Elements in Health ; Neuroscience and Neuropharmacology Research
Authors: Joshua J. Woods | Robyn J. Novorolsky | Nicholas P. Bigham | George S. Robertson | Justin J. Wilson
Source: RSC Chemical Biology (article, 2022-11-14)
Field: Chemistry — Spectroscopy

Dinuclear nitrido-bridged osmium complexes inhibit the mitochondrial calcium uniporter and protect cortical neurons against lethal oxygen–glucose deprivation Dysregulation of mitochondrial calcium uptake mediated by the mitochondrial calcium uniporter (MCU) is implicated in several pathophysiological conditions. Dinuclear ruthenium complexes are effective inhibitors of the MCU and have been leveraged as both tools to study mitochondrial calcium dynamics and potential therapeutic agents. In this study, we report the synthesis and characterization of Os245 ([Os<sub>2</sub>(μ-N)(NH<sub>3</sub>)<sub>8</sub>Cl<sub>2</sub>]<sup>3+</sup>) which is the osmium-containing analogue of our previously reported ruthenium-based inhibitor Ru265. This complex and its aqua-capped analogue Os245' ([Os<sub>2</sub>(μ-N)(NH<sub>3</sub>)<sub>8</sub>(OH<sub>2</sub>)<sub>2</sub>]<sup>5+</sup>) are both effective inhibitors of the MCU in permeabilized and intact cells. In comparison to the ruthenium-based inhibitor Ru265 (<i>k</i> <sub>obs</sub> = 4.92 × 10<sup>-3</sup> s<sup>-1</sup>), the axial ligand exchange kinetics of Os245 are two orders of magnitude slower (<i>k</i> <sub>obs</sub> = 1.63 × 10<sup>-5</sup> s<sup>-1</sup>) at 37 °C. The MCU-inhibitory properties of Os245 and Os245' are different (Os245 IC<sub>50</sub> for MCU inhibition = 103 nM; Os245' IC<sub>50</sub> for MCU inhibition = 2.3 nM), indicating that the axial ligands play an important role in their interactions with this channel. We further show that inhibition of the MCU by these complexes protects primary cortical neurons against lethal oxygen-glucose deprivation. When administered <i>in vivo</i> to mice (10 mg kg<sup>-1</sup>), Os245 and Os245' induce seizure-like behaviors in a manner similar to the ruthenium-based inhibitors. However, the onset of these seizures is delayed, a possible consequence of the slower ligand substitution kinetics for these osmium complexes. These findings support previous studies that demonstrate inhibition of the MCU is a promising therapeutic strategy for the treatment of ischemic stroke, but also highlight the need for improved drug delivery strategies to mitigate the pro-convulsant effects of this class of complexes before they can be implemented as therapeutic agents. Furthermore, the slower ligand substitution kinetics of the osmium analogues may afford new strategies for the development and modification of this class of MCU inhibitors. Uniporter ; Ruthenium red ; Osmium ; Ruthenium ; Chemistry ; Calcium ; Mitochondrion ; Biophysics ; Ligand (biochemistry) ; IC50 ; Kinetics ; Biochemistry ; In vivo ; Oxygen ; Inhibitory postsynaptic potential ; Receptor ; Cytosol ; Biology ; In vitro ; Neuroscience ; Enzyme ; Catalysis Molecular Sensors and Ion Detection ; Neuroscience and Neuropharmacology Research ; Electrochemical sensors and biosensors
Authors: Pritom J. Bora | Bibhusita Mahanta | Praveen C. Ramamurthy
Source: Composites Communications (article, 2022-08-19)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Optimization of polyaniline nanofiber loading in polymer matrix for strong microwave absorption using materials data-driven discovery Materials science ; Polyvinyl butyral ; Polyaniline ; Reflection loss ; Microwave ; Composite material ; Percolation threshold ; Composite number ; Absorption (acoustics) ; Polymer ; Computer science ; Telecommunications ; Electrical resistivity and conductivity ; Electrical engineering Electromagnetic wave absorption materials ; Advanced Antenna and Metasurface Technologies ; Antenna Design and Analysis
Authors: Richard S. Hong | Alessandra Mattei | Ahmad Y. Sheikh | Mark E. Tuckerman
Source: Proceedings of the National Academy of Sciences (article, 2022-10-17)
Field: Chemistry — Physical and Theoretical Chemistry

A data-driven and topological mapping approach for the a priori prediction of stable molecular crystalline hydrates Predictions of the structures of stoichiometric, fractional, or nonstoichiometric hydrates of organic molecular crystals are immensely challenging due to the extensive search space of different water contents, host molecular placements throughout the crystal, and internal molecular conformations. However, the dry frameworks of these hydrates, especially for nonstoichiometric or isostructural dehydrates, can often be predicted from a standard anhydrous crystal structure prediction (CSP) protocol. Inspired by developments in the field of drug binding, we introduce an efficient data-driven and topologically aware approach for predicting organic molecular crystal hydrate structures through a mapping of water positions within the crystal structure. The method does not require <i>a priori</i> specification of water content and can, therefore, predict stoichiometric, fractional, and nonstoichiometric hydrate structures. This approach, which we term a <i>mapping approach for crystal hydrates</i> (MACH), establishes a set of rules for systematic determination of favorable positions for water insertion within predicted or experimental crystal structures based on considerations of the chemical features of local environments and void regions. The proposed approach is tested on hydrates of three pharmaceutically relevant compounds that exhibit diverse crystal packing motifs and void environments characteristic of hydrate structures. Overall, we show that our mapping approach introduces an advance in the efficient performance of hydrate CSP through generation of stable hydrate stoichiometries at low cost and should be considered an integral component for CSP workflows. Hydrate ; Stoichiometry ; Anhydrous ; Isostructural ; Crystal (programming language) ; Clathrate hydrate ; Materials science ; Crystal structure ; Molecule ; Chemistry ; Chemical physics ; Crystallography ; Computer science ; Physical chemistry ; Organic chemistry Crystallography and molecular interactions ; Crystallization and Solubility Studies ; Computational Drug Discovery Methods
Authors: Jiangang He | Karin M. Rabe | Chris Wolverton
Source: MRS Bulletin (article, 2022-06-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Computationally accelerated discovery of functional and structural Heusler materials Heusler compound ; Spintronics ; Materials science ; Thermoelectric materials ; Intermetallic ; Nanotechnology ; Engineering physics ; Condensed matter physics ; Ferromagnetism ; Alloy ; Physics ; Metallurgy ; Metal Heusler alloys: electronic and magnetic properties ; Machine Learning in Materials Science ; MXene and MAX Phase Materials