jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Hyeonhwa Lee | Jinsoo Kim | Sungcheul Lee | Jong‐Eun Park | Jeongyeon Park | Jongsu Kim
Source: Micromachines (article, 2023-03-16)
Field: Materials Science — Materials Chemistry

Effect of Coating Thickness on Abrasion and Cutting Performance of NCD-Coated Ball Endmills on Graphite Machining Nano-crystalline diamond (NCD) coating to improve the performance of cutting tools, as the coating thickness varies, the cutting performance and lifespan of the tool varies because the radius of its cutting edge and coating surface roughness are altered. Therefore, an in-depth analysis on the impact of the variations in coating thickness on the cutting tool abrasion and quality of machined surface is necessary. In this study, two NCD ball endmills were coated with 8 and 12 μm thicknesses, and the tool abrasion and roughness of the machined plane were observed after milling. Furthermore, the morphology of the coated surface and abrased cutting edge were observed using a 3D confocal microscope. Consequently, we observed that individual nodules were formed on the continuous aggregates as the coating thickness increased, which increased the coated surface roughness. The two damage modes of the aggregation determined the dominant abrasion that occurred on the cutting edges of both types of coating thicknesses. Delamination and crater wear caused a sharp increase in the roughness of the machined surface. In summary, the increase in coating thickness delayed the delamination of the coating but increased the roughness of the cutting edge, which reduced the machined surface roughness. Materials science ; Coating ; Composite material ; Surface roughness ; Surface finish ; Machining ; Enhanced Data Rates for GSM Evolution ; Delamination (geology) ; Abrasion (mechanical) ; Metallurgy Diamond and Carbon-based Materials Research ; Advanced machining processes and optimization ; Tunneling and Rock Mechanics
Authors: Sercan Yıldırım
Source: Turkish Journal of Analytical Chemistry (article, 2023-11-22)
Field: Chemistry — Spectroscopy

A green liquid chromatographic method using ethanol in mobile phase for the determination of nimesulide and naproxen in gel formulations Dеtеrmination of nonsteroidal anti-inflammatory drugs (NSAIDs) in pharmacеutical formulations hеlps to еnsurе that thеy arе manufacturеd to thе corrеct spеcifications. Consequently, simple, reliable, and environmentally friendly analytical methods are needed for the quality control of NSAID formulations. In this study, a novel and green liquid chromatographic method was developed for the determination of nimesulide (NIM) and naproxen (NAP) in gel formulations by employing ethanol as a green alternative to hazardous methanol and acetonitrile. The high viscosity of ethanol was compensated by employing a Chromolith HighResolution RP18e monolithic column (100 × 4.6 mm) with low flow resistance. Box-Behnken design with desirability function was employed for the optimization of selected significant parameters: pH (2.8-4), ethanol ratio in the mobile phase (35-55%), and flow rate (0.7-1.5 mL/min). Under optimum conditions, satisfactory separation of analytes was achieved within 5 min. Calibration curves for both analytes were linear between 1-50 μg/mL. Accuracies of intra- and inter-day experiments at low-, middle-, and high-quality control levels ranged from 99.0-101.5% with relative standard deviation values lower than 2.3%. The limits of detection were 0.27 and 0.62 µg/mL for NIM and NAP, respectively. The applicability of the method was demonstrated by analyzing gel formulations. The results of this study indicated that monolithic columns in combination with ethanol as a mobile phase component could be considered a desirable and green alternative for the routine analysis of NSAIDs in quality control laboratories. Chromatography ; Nimesulide ; Naproxen ; Chemistry ; Analyte ; High-performance liquid chromatography ; Calibration curve ; Propylparaben ; Detection limit ; Organic chemistry Analytical Chemistry and Chromatography ; Analytical Methods in Pharmaceuticals ; Inflammatory mediators and NSAID effects
Authors: Felix Grünberger | Georg H. Schmid | Zubeir El Ahmad | Martin Fenk | Katharina Vogl | Robert Reichelt | Winfried Hausner | Henning Urlaub | Christof Lenz | Dina Grohmann
Source: bioRxiv (Cold Spring Harbor Laboratory) (preprint, 2023-05-02)
Field: Materials Science — Materials Chemistry

Uncovering the temporal dynamics and regulatory networks of thermal stress response in a hyperthermophile using transcriptomics and proteomics Abstract Extremophiles, such as the hyperthermophilic archaeon Pyrococcus furiosus , thrive under extreme conditions and must rapidly adapt to changes in the physical parameters of their natural environment for short-term and long-term survival. When inhabiting hydrothermal vents, these organisms face substantial temperature gradients, necessitating the evolution of adaptive thermal stress mechanisms. However, the dynamics and coordination of cellular responses at the transcriptome and proteome levels remain underexplored. This study presents an integrated analysis of RNA-sequencing and mass spectrometry data to elucidate the transcriptomic and proteomic responses to heat and cold shock stress and recovery in P. furiosus . Our results reveal surprisingly rapid and dynamic changes in gene and protein expression patterns associated with these stress responses. Heat shock triggers extensive transcriptome reprogramming, orchestrated by the transcriptional regulator Phr, which targets a broader gene repertoire than previously demonstrated. For heat shock signature genes, RNA levels swiftly return to baseline upon recovery, while protein levels remain persistently upregulated, reflecting a rapid but more sustained response. Intriguingly, cold shock at 4°C elicits distinct short-term and long-term responses at both RNA and protein levels. By conducting a cluster analysis, we identified gene sets with either congruent or contrasting trends in RNA and protein changes. Notably, these clusters represent well-separated arCOG groups and appear to be tailored to their individual cellular responses. Our study provides a comprehensive overview of the cellular response to temperature stress, advancing our understanding of stress response mechanisms in hyperthermophilic archaea and provide valuable insights into the molecular adaptations that facilitate life in extreme environments. Pyrococcus furiosus ; Transcriptome ; Biology ; Proteome ; RNA-Seq ; Heat shock protein ; Heat shock ; Proteomics ; Computational biology ; RNA ; Gene ; Hyperthermophile ; Cellular stress response ; Cell biology ; Gene expression ; Archaea ; Genetics ; Fight-or-flight response Enzyme Structure and Function ; Microbial Community Ecology and Physiology ; Genomics and Phylogenetic Studies
Authors: Rémi F. André | Alberto Palazzolo | Cyprien Poucin | François Ribot | Sophie Carenco
Source: ChemPlusChem (article, 2023-03-02)
Field: Chemistry — Organic Chemistry

Phosphine‐Catalyzed Activation of Phenylsilane for Benzaldehyde Reduction Hydrosilylation reactions are commonly used for the reduction of carbonyl bonds in fine chemistry, catalyzed by transition metal complexes. The current challenge is to expand the scope of metal-free alternative catalysts, including in particular organocatalysts. This work describes the organocatalyzed hydrosilylation of benzaldehyde with a phosphine, introduced at 10 mol%, and phenylsilane at room temperature. The activation of phenylsilane was highly dependent on the physical properties of the solvent such as the polarity, and the highest conversions were obtained in acetonitrile and propylene carbonate with yields of 46 % and 97 %, respectively. The best results of the screening over 13 phosphines and phosphites were obtained with linear trialkylphoshines (PMe<sub>3</sub> , P<sup>n</sup> Bu<sub>3</sub> , POct<sub>3</sub> ), indicating the importance of their nucleophilicity, with yields of 88 %, 46 % and 56 %, respectively. With the help of heteronuclear <sup>1</sup> H-<sup>29</sup> Si NMR spectroscopy, the products of the hydrosilylation (PhSiH<sub>3-n</sub> (OBn)<sub>n</sub> ) were identified, allowing a monitoring of the concentration in the different species, and thereby of their reactivity. The reaction displayed an induction period of ca. 60 min, followed by the sequential hydrosilylations presenting various reaction rates. In agreement with the formation of partial charges in the intermediate state, we propose a mechanism based on a hypervalent silicon center via the Lewis base activation of the silicon Lewis acid. Phenylsilane ; Phosphine ; Catalysis ; Benzaldehyde ; Reduction (mathematics) ; Chemistry ; Organic chemistry ; Photochemistry ; Mathematics Organoboron and organosilicon chemistry ; Asymmetric Hydrogenation and Catalysis ; Chemical Synthesis and Reactions
Authors: Kexin Yan | Zhaoqi Ye | Lingtao Kong | Li He | Xue Yang | Yahong Zhang | Hongbin Zhang | Yi Tang
Source: Acta Physico-Chimica Sinica (article, 2023-10-18)
Field: Chemistry — Inorganic Chemistry

Seed-Induced Synthesis of Disc-Cluster Zeolite L Mesocrystals with Ultrashort c-Axis: Morphology Control, Decoupled Mechanism, and Enhanced Adsorption Zeolite ; Morphology (biology) ; Mechanism (biology) ; Cluster (spacecraft) ; Materials science ; Crystallography ; Adsorption ; Chemistry ; Chemical engineering ; Nanotechnology ; Physics ; Engineering ; Physical chemistry ; Computer science ; Geology ; Organic chemistry ; Catalysis Zeolite Catalysis and Synthesis ; Mesoporous Materials and Catalysis ; Nanomaterials for catalytic reactions
Authors: Robert Herzhoff | Fabrizia Negri | Klaus Meerholz | Daniele Fazzi
Source: Journal of Materials Chemistry C (article, 2023-01-01)
Field: Materials Science — Polymers and Plastics

Revealing the interplay between the structural complexity of triphenylamine redox derivatives and their charge transport processes <i>via</i> computational modeling Triphenylamine derivatives (TPAs) are known for their semiconducting charge transport and redox properties. We explore computationally the charge transport processes in amorphous and single crystalline phases of four different TPAs. Triphenylamine ; Redox ; Charge (physics) ; Materials science ; Amorphous solid ; Chemical physics ; Nanotechnology ; Computational chemistry ; Crystallography ; Chemistry ; Optoelectronics ; Physics Conducting polymers and applications ; Electrochemical Analysis and Applications ; Organic Electronics and Photovoltaics
Authors: Evangelos Pilichos | Ànnia Tubau | Saskia Speed | Mercè Font-Bardı́a | Albert Escuer | Arnald Grabulosa | Júlia Mayans
Source: Dalton Transactions (article, 2023-01-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Magnetic and optical studies of a new family of multidimensional and multiproperty PO-lanthanide(<scp>iii</scp>) derived systems A new family of lanthanide compounds has been synthesized using 1,2-bis(diphenylphosphino)ethane dioxide (dppeO<sub>2</sub>) as an O-donor ligand through the phosphoryl group to lanthanide(III) cations and structurally, magnetically and optically studied. Depending on the lanthanide, two different topologies appear: the two-dimensional structure [Ln<sup>III</sup>(dppeO<sub>2</sub>)<sub>1.5</sub>(NO<sub>3</sub>)<sub>3</sub>(H<sub>2</sub>O)<sub>0.5</sub>]<sub><i>n</i></sub> (Ln = Ce (1), Sm (2) and Dy (6)) and the one-dimensional structure [Ln(dppeO<sub>2</sub>)(NO<sub>3</sub>)<sub>3</sub>DMF]<sub><i>n</i></sub> (Ln = Eu (3), Gd (4) and Tb (5)). Some of the Ln-derived complexes have been used as structural probes, while others have been synthesized to use the specific characteristics of each cation to take advantage of their magnetic/luminescence properties. Complex 6 presents slow relaxation of the magnetization while 2, 3 and 5 present emitting properties in the visible range. Lanthanide ; Physics ; Materials science ; Chemistry ; Quantum mechanics ; Ion Magnetism in coordination complexes ; Lanthanide and Transition Metal Complexes ; Electron Spin Resonance Studies
Authors: Martin Gläser | Paul Mollenkopf | Dušan Praščević | Catarina Ferraz | Josef A. Käs | Jörg Schnauß | David M. Smith
Source: Nanoscale (article, 2023-01-01)
Field: Materials Science — Surfaces, Coatings and Films

Systematic altering of semiflexible DNA-based polymer networks <i>via</i> tunable crosslinking In order to understand and predict the mechanical behaviours of complex, soft biomaterials such as cells or stimuli-responsive hydrogels, it is important to connect how the nanoscale properties of their constituent components impact those of the bulk material. Crosslinked networks of semiflexible polymers are particularly ubiquitous, being underlying mechanical components of biological systems such as cells or ECM, as well as many synthetic or biomimetic materials. Cell-derived components such as filamentous biopolymers or protein crosslinkers are readily available and well-studied model systems. However, as evolutionarily derived materials, they are constrained to a fixed set of structural parameters such as the rigidity and size of the filaments, or the valency and strength of binding of crosslinkers forming inter-filament connections. By implementing a synthetic model system based on the self-assembly of DNA oligonucleotides into nanometer-scale tubes and simple crosslinking constructs, we used the thermodynamic programmability of DNA hybridization to explore the impact of binding affinity on bulk mechanical response. Stepwise tuning the crosslinking affinity over a range from transient to thermodynamically stable shows an according change in viscoelastic behaviour from loosely entangled to elastic, consistent with models accounting for generalized inter-filament interactions. While characteristic signatures of concentration-dependent changes in network morphology found in some other natural and synthetic filament-crosslinker systems were not apparent, the presence of a distinct elasticity increase within a narrow range of conditions points towards potential subtle alterations of crosslink-filament architecture. Here, we demonstrate a new synthetic approach for gaining a deeper understanding of both biological as well as engineered hydrogel systems. Biopolymer ; Polymer ; DNA ; Materials science ; Polymer science ; Nanotechnology ; Chemistry ; Composite material Polymer Surface Interaction Studies ; Molecular Junctions and Nanostructures ; Advanced Polymer Synthesis and Characterization
Authors: Tommaso Antonelli | Akhil Rajan | Matthew D. Watson | Shoresh Soltani | J. D. Houghton | Gesa-R. Siemann | Andela Zivanovic | Chiara Bigi | Brendan Edwards | P. D. C. King
Source: Nano Letters (article, 2023-12-20)
Field: Materials Science — Materials Chemistry

Controlling the Charge Density Wave Transition in Single-Layer TiTe<sub>2<i>x</i></sub>Se<sub>2(1–<i>x</i>)</sub> Alloys by Band Gap Engineering Closing the band gap of a semiconductor into a semimetallic state gives a powerful potential route to tune the electronic energy gains that drive collective phases like charge density waves (CDWs) and excitonic insulator states. We explore this approach for the controversial CDW material monolayer (ML) TiSe<sub>2</sub> by engineering its narrow band gap to the semimetallic limit of ML-TiTe<sub>2</sub>. Using molecular beam epitaxy, we demonstrate the growth of ML-TiTe<sub>2<i>x</i></sub>Se<sub>2(1-<i>x</i>)</sub> alloys across the entire compositional range and unveil how the (2 × 2) CDW instability evolves through the normal state semiconductor-semimetal transition via <i>in situ</i> angle-resolved photoemission spectroscopy. Through model electronic structure calculations, we identify how this tunes the relative strength of excitonic and Peierls-like coupling, demonstrating band gap engineering as a powerful method for controlling the microscopic mechanisms underpinning the formation of collective states in two-dimensional materials. Charge density wave ; Condensed matter physics ; Materials science ; Band gap ; Layer (electronics) ; Transition metal ; Charge (physics) ; Crystallography ; Physics ; Chemistry ; Nanotechnology 2D Materials and Applications ; Chalcogenide Semiconductor Thin Films ; Perovskite Materials and Applications
Authors: E. Rowe | Bo Yuan | M. Buzzi | G. Jotzu | Y. Zhu | M. Fechner | M. Först | Bo Liu | D. Pontiroli | M. Riccò | A. Cavalleri
Source: arXiv (Cornell University) (preprint, 2023-01-20)
Field: Materials Science — Materials Chemistry

Giant resonant enhancement for photo-induced superconductivity in K$_3$C$_{60}$ Photo-excitation at terahertz and mid-infrared frequencies has emerged as a new way to manipulate functionalities in quantum materials, in some cases creating non-equilibrium phases that have no equilibrium analogue. In K$_3$C$_{60}$, a metastable zero-resistance phase was documented with optical properties and pressure dependences compatible with non-equilibrium high temperature superconductivity. Here, we report the discovery of a dominant energy scale for this phenomenon, along with the demonstration of a giant increase in photo-susceptibility near 10 THz excitation frequency. At these drive frequencies a metastable superconducting-like phase is observed up to room temperature for fluences as low as ~400 $μJ/cm^2$. These findings shed light on the microscopic mechanism underlying photo-induced superconductivity. They also trace a path towards steady state operation, currently limited by the availability of a suitable high-repetition rate optical source at these frequencies. Metastability ; Superconductivity ; Terahertz radiation ; Excitation ; Condensed matter physics ; Phase (matter) ; Materials science ; Infrared ; Thermodynamic equilibrium ; Optoelectronics ; Physics ; Optics ; Thermodynamics ; Quantum mechanics Diamond and Carbon-based Materials Research ; High-pressure geophysics and materials ; Fullerene Chemistry and Applications
Authors: Jonas Neumann | Sebastian Schmidtsdorff | Alexander H. Schmidt | Maria Kristina Parr
Source: Journal of Separation Science (article, 2023-01-05)
Field: Chemistry — Spectroscopy

Ternary eluent compositions in supercritical fluid chromatography improved fingerprinting of therapeutic peptides Currently, little information has been published on the application of ternary eluent compositions in supercritical fluid chromatography for separating peptides. This work investigates the benefits of adding acetonitrile to methanol as the modifier. Three cyclic antibiotic peptides (bacitracin, colistin, and daptomycin) ranging between 1000 and 2000 Da were chosen as model substances. The ternary mixture of carbon dioxide, methanol, and acetonitrile is optimized to increase the resolution of the peptide's fingerprint. In addition, varying compositions of methanol and acetonitrile were found to change the elution order of the analytes, which is a valuable tool during method development. An individual gradient method using two Torus 2-PIC columns (each 100 × 3.0 mm, 1.7 μm), carbon dioxide, and a modifier consisting of acetonitrile/methanol/water/methanesulfonic acid (60:40:2:0.1, v:v:v:v) was optimized for each of the peptides. Subsequently, a generic method development protocol applicable to polypeptides is proposed. Chemistry ; Supercritical fluid chromatography ; Acetonitrile ; Chromatography ; Methanol ; Elution ; Column chromatography ; Ternary operation ; Organic chemistry Analytical Chemistry and Chromatography ; Chromatography in Natural Products ; Mass Spectrometry Techniques and Applications
Authors: C. F. Aliotta | M.L. Costa | Leonarda Francesca Liotta | Valeria La Parola | Giuliana Magnacca | Francesca Deganello
Source: Molecules (article, 2023-02-08)
Field: Materials Science — Materials Chemistry

Peculiar Properties of the La0.25Ba0.25Sr0.5Co0.8Fe0.2O3−δ Perovskite as Oxygen Reduction Electrocatalyst The electrochemical reduction of molecular oxygen is a fundamental process in Solid Oxide Fuel Cells and requires high efficiency cathode materials. Two La<sub>0.25</sub>Ba<sub>0.25</sub>Sr<sub>0.5</sub>Co<sub>0.8</sub>Fe<sub>0.2</sub>O<sub>3-δ</sub>-based perovskite compounds were prepared by solution combustion synthesis, and characterized for their structural, microstructural, surface, redox and electrochemical properties as potential cathodes in comparison with Ba<sub>0.5</sub>Sr<sub>0.5</sub>Co<sub>0.8</sub>Fe<sub>0.2</sub>O<sub>3-δ</sub> and La<sub>0.5</sub>Sr<sub>0.5</sub>Co<sub>0.8</sub>Fe<sub>0.2</sub>O<sub>3-δ</sub> perovskites. Results highlighted that calcination at 900 °C led to a "bi-perovskite heterostructure", where two different perovskite structures coexist, whereas at higher calcination temperatures a single-phase perovskite was formed. The results showed the effectiveness of the preparation procedures in co-doping the A-site of perovskites with barium and lanthanum as a strategy to optimize the cathode's properties. The formation of nanometric heterostructure co-doped in the A-site evidenced an improvement in oxygen vacancies' availability and in the redox properties, which promoted both processes: oxygen adsorption and oxygen ions drift, through the cathode material, to the electrolyte. A reduction in the total resistance was observed in the case of heterostructured material. Electrocatalyst ; Perovskite (structure) ; Oxygen reduction ; Oxygen reduction reaction ; Oxygen ; Chemistry ; Reduction (mathematics) ; Materials science ; Chemical engineering ; Crystallography ; Physical chemistry ; Electrode ; Electrochemistry ; Organic chemistry Advancements in Solid Oxide Fuel Cells ; Magnetic and transport properties of perovskites and related materials ; Electronic and Structural Properties of Oxides
Authors: Nipal Deka | Alexander Stukowski | Ryan B. Sills
Source: Acta Materialia (article, 2023-06-21)
Field: Materials Science — Materials Chemistry

Automated extraction of interfacial dislocations and disconnections from atomistic data Materials science ; Grain boundary ; Interface (matter) ; Burgers vector ; Boundary (topology) ; Phase (matter) ; Deformation (meteorology) ; Surface (topology) ; Line (geometry) ; Twist ; Orientation (vector space) ; Crystallography ; Condensed matter physics ; Geometry ; Dislocation ; Mathematical analysis ; Microstructure ; Composite material ; Physics ; Mathematics Machine Learning in Materials Science ; Electronic and Structural Properties of Oxides ; Advanced Materials Characterization Techniques
Authors: Shuhei Kindaichi | Ryosuke Matsubara | Atsushi Kubono | S. Yamamoto | Masaya Mitsuishi
Source: ChemRxiv (preprint, 2023-04-25)
Field: Materials Science — Polymers and Plastics

Preparation of Resilient Organic Electrochemical Transistors Based on Blend Films with Flexible Crosslinkers Organic electrochemical transistors (OECTs) exhibit high biocompatibility and are expected to be applied in biological sensors. This study focused on crosslinking agents in blend films of a mixed conducting polymer, poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS), and a thermoresponsive polymer, poly(N-isopropylacrylamide) (PNIPAM), as channel layers to realize reversible temperature response. In addition to the conventional (3-glycidyloxypropyl) trimethoxysilane (GOPS) crosslinker, a poly(ethylene glycol) diglycidyl ether (PEGDE) flexible crosslinker was used to overcome the volume expansion caused by the temperature change. Structural analysis revealed that PNIPAM was segregated on the surface and that the PEGDE crosslinker increased the crystallinity of PEDOT. Blend films with binary crosslinkers (PEGDE and GOPS) exhibited reversible response to temperature cycling. Therefore, the use of a flexible crosslinker in functional blend films can facilitate the fabrication of biosensing OECT devices with higher resilience to the fluctuation of surrounding conditions. PEDOT:PSS ; Materials science ; Ethylene glycol ; Chemical engineering ; Polymer ; Conductive polymer ; Crystallinity ; Polymer chemistry ; Electrochemistry ; Biocompatibility ; Nanotechnology ; Electrode ; Composite material ; Chemistry Conducting polymers and applications ; Analytical Chemistry and Sensors ; Advanced Sensor and Energy Harvesting Materials