jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Chandra Ade‐Browne | Marzieh Mirzamani | Arnab Dawn | Shuo Qian | Ryan Thompson | Robert W. Glenn | Harshita Kumari
Source: Colloids and Surfaces A Physicochemical and Engineering Aspects (article, 2020-03-16)
Field: Chemistry — Organic Chemistry

Effect of ethoxylation and lauryl alcohol on the self-assembly of sodium laurylsulfate: Significant structural and rheological transformation Alcohol ; Sodium ; Chemistry ; Rheology ; Transformation (genetics) ; Materials science ; Organic chemistry ; Composite material ; Biochemistry Surfactants and Colloidal Systems ; Pickering emulsions and particle stabilization ; Proteins in Food Systems
Authors: Worathep Sae‐Long | Suchart Limkatanyu | Woraphot Prachasaree | Jaroon Rungamornrat | Piti Sukontasukkul
Source: Journal of Nanomaterials (article, 2020-05-16)
Field: Materials Science — Materials Chemistry

A Thermodynamics-Based Nonlocal Bar-Elastic Substrate Model with Inclusion of Surface-Energy Effect This paper presents a bar-elastic substrate model to investigate the axial responses of nanowire-elastic substrate systems considering the effects of nonlocality and surface energy. The thermodynamics-based strain gradient model is adopted to capture the nonlocality of the bar-bulk material while the Gurtin-Murdoch surface theory is utilized to consider the surface energy. To characterize the bar-surrounding substrate interaction, the Winkler foundation model is employed. In a direct manner, system compatibility conditions are obtained while within the framework of the virtual displacement principle, the system equilibrium condition and the corresponding natural boundary conditions are consistently obtained. Three numerical simulations are conducted to investigate the characteristics and behaviors of the nanowire-elastic substrate system: the first is conducted to reveal the capability of the proposed model to eliminate the paradoxical behavior inherent to the Eringen nonlocal differential model; the second is employed to characterize responses of the nanowire-elastic substrate system; and the third is aimed at demonstrating the dependence of the system effective Young’s modulus on several system parameters. Materials science ; Quantum nonlocality ; Boundary value problem ; Surface energy ; Substrate (aquarium) ; Bar (unit) ; Elastic energy ; Nanowire ; Modulus ; Mechanics ; Thermodynamics ; Physics ; Nanotechnology ; Composite material Nonlocal and gradient elasticity in micro/nano structures ; Thermoelastic and Magnetoelastic Phenomena ; Microstructure and mechanical properties
Authors: Paul Ben Ishai | Michelle K. Kidder | А. И. Колесников | Lawrence M. Anovitz
Source: The Journal of Physical Chemistry Letters (article, 2020-08-26)
Field: Materials Science — Materials Chemistry

One-Dimensional Glassy Behavior of Ultraconfined Water Strings Water is renowned for its anomalous behaviors, which can be linked to a distributed H-bond network in bulk water. Ultraconfinement of the water molecule can remove H-bonding, leaving only molecular water. In natural cordierite crystals, water is trapped in an orthorhombic channel with an average diameter of 5.7 Å, running through the center of the unit cell parallel to the <i>c</i>-axis. Calorimetric measurements reveal the existence of a one-dimensional (1D) glass linked to this water. In these channels, water molecules in truncated, sparse 1D strings interact only via dipole-dipole correlations. A physical 1D glass is formed from these strings. This unusual state can be explained by a modified Ising model. This model predicts a dependence of the glass transition temperature, <i>T</i><sub>g</sub>, on the size of these domains. This is confirmed experimentally. Orthorhombic crystal system ; Dipole ; Ising model ; Glass transition ; Molecule ; Chemical physics ; Hydrogen bond ; Materials science ; Condensed matter physics ; Chemistry ; Crystallography ; Physics ; Crystal structure ; Composite material ; Polymer Material Dynamics and Properties ; Theoretical and Computational Physics ; Spectroscopy and Quantum Chemical Studies
Authors: Eyas Mahmoud
Source: Applied Sciences (article, 2020-10-31)
Field: Chemistry — Inorganic Chemistry

Mitigating Global Methane Emissions Using Metal-Organic Framework Adsorbents Global emission of methane reached a record high in 2020. Furthermore, it is expected that methane emissions will continue to rise in the coming years despite the economic slowdown stemming from the coronavirus pandemic. Adsorbents can be used to reduce methane emissions. However, the question remains as to which adsorbents perform best for enhanced methane capture. In this work, it is demonstrated that metal-organic frameworks (MOFs) exhibited the best methane uptakes at 1 bar and 298 K from experiments as compared to tested carbonaceous materials, polymers, and zeolites. In addition, the adsorption entropy, an important thermodynamic property indicating adsorption capacity and kinetics, is determined on well-defined MOFs using a global predictive equation for porous materials. A correlation was used to describe the effect of translation and rotation of methane in the porous material for methane emission abatement. This information and the entropy of adsorption of methane on MOFs has not been reported before. The predicted results were compared to experimental data obtained from adsorption isotherms. Optimum isosteric heats were calculated by the Bhatia and Myers correlation. Finally, the pre-exponential factor of desorption is determined to aid in the design of materials for global methane emissions mitigation. Methane ; Adsorption ; Materials science ; Metal-organic framework ; Desorption ; Chemical engineering ; Chemistry ; Thermodynamics ; Environmental science ; Physical chemistry ; Organic chemistry ; Physics Metal-Organic Frameworks: Synthesis and Applications ; Carbon Dioxide Capture Technologies ; Covalent Organic Framework Applications
Authors: Diána Balogh‐Weiser | Balázs Decsi | Réka Krammer | Gergő Dargó | Ferenc Ender | J. Mizsei | Róbert Berkecz | Benjámin Gyarmati | András Szilágyi | Róbert Tőtős | Csaba Paizs | László Poppe | György T. Balogh
Source: Nanomaterials (article, 2020-11-24)
Field: Materials Science — Materials Chemistry

Magnetic Nanoparticles with Dual Surface Functions—Efficient Carriers for Metalloporphyrin-Catalyzed Drug Metabolite Synthesis in Batch and Continuous-Flow Reactors The dual functionalization of magnetic nanoparticles with inert (methyl) and reactive (aminopropyl) groups enables efficient immobilization of synthetic metalloporphyrins (such as 5,10,15,20-tetrakis(2,3,4,5,6-pentafluorophenyl)iron(II) porphyrin and 5,10,15,20-tetrakis-(4-sulfonatophenyl)iron(II) porphyrin) via covalent or ionic interactions. The proportion of reactive function on the surface has significant effect on the biomimetic activity of metalloporphyrins. The optimized magnetic nanocatalyst containing porphyrin was successfully applied for biomimetic oxidation of antihypertensive drug Amlodipine in batch and continuous-flow reactors as well. Porphyrin ; Surface modification ; Catalysis ; Combinatorial chemistry ; Magnetic nanoparticles ; Chemistry ; Nanoparticle ; Ionic bonding ; Covalent bond ; Chemical engineering ; Materials science ; Photochemistry ; Organic chemistry ; Nanotechnology ; Physical chemistry Porphyrin and Phthalocyanine Chemistry ; Innovative Microfluidic and Catalytic Techniques Innovation ; Electrochemical sensors and biosensors
Authors: Vanessa Koch | Martin Nieger | Stefan Bräse
Source: Organic Chemistry Frontiers (article, 2020-01-01)
Field: Materials Science — Biomaterials

Towards the synthesis of calotropin and related cardenolides from 3-epiandrosterone: A-ring related modifications Calotropin and related cardiac glycosides isolated from plants such as <italic>calotropis gigantea</italic> represent an interesting target for biological investigations and are based on a cardiac steroid that is doubly connected to a sugar moiety. Cardenolide ; Chemistry ; Glycoside ; Cardiac glycoside ; Moiety ; Ring (chemistry) ; Stereochemistry ; Steroid ; Sugar ; Organic chemistry ; Biochemistry ; Hormone Phytochemistry and Bioactive Compounds ; Phytochemical Studies and Bioactivities ; Marine Sponges and Natural Products
Authors: Jon Azpeitia | Irene Palacio | José I. Martínez | Isabel Muñoz-Ochando | Koen Lauwaet | F. J. Mompeán | Gary Ellis | M. Garcı́a-Hernández | José Á. Martín‐Gago | Carmen Munuera | María Francisca López
Source: Applied Surface Science (article, 2020-07-11)
Field: Materials Science — Materials Chemistry

Oxygen intercalation in PVD graphene grown on copper substrates: A decoupling approach We investigate the intercalation process of oxygen in-between a PVD-grown graphene layer and different copper substrates as a methodology for reducing the substrate-layer interaction. This growth method leads to an extended defect-free graphene layer that strongly couples with the substrate. We have found, by means of X-ray photoelectron spectroscopy, that after oxygen exposure at different temperatures, ranging from 280 °C to 550 °C, oxygen intercalates at the interface of graphene grown on Cu foil at an optimal temperature of 500 °C. The low energy electron diffraction technique confirms the adsorption of an atomic oxygen adlayer on top of the Cu surface and below graphene after oxygen exposure at elevated temperature, but no oxidation of the substrate is induced. The emergence of the 2D Raman peak, quenched by the large interaction with the substrate, reveals that the intercalation process induces a structural undoing. As suggested by atomic force microscopy, the oxygen intercalation does not change significantly the surface morphology. Moreover, theoretical simulations provide further insights into the electronic and structural undoing process. This protocol opens the door to an efficient methodology to weaken the graphene-substrate interaction for a more efficient transfer to arbitrary surfaces. Graphene ; Intercalation (chemistry) ; Raman spectroscopy ; Materials science ; X-ray photoelectron spectroscopy ; Oxygen ; Copper ; Substrate (aquarium) ; Graphene nanoribbons ; Low-energy electron diffraction ; Chemical physics ; Chemical engineering ; Nanotechnology ; Inorganic chemistry ; Chemistry ; Electron diffraction ; Diffraction ; Metallurgy ; Optics Graphene research and applications ; Semiconductor materials and devices ; ZnO doping and properties
Authors: Liam Connah | Goran Angelovski
Source: Organic Chemistry Frontiers (article, 2020-01-01)
Field: Materials Science — Materials Chemistry

Solid phase synthesis in the development of magnetic resonance imaging probes We review the use of the solid phase synthesis methodology for the preparation of diverse and potent MRI probes. Chemistry ; Solid-phase synthesis ; Phase (matter) ; Magnetic resonance imaging ; Nuclear magnetic resonance ; Nanotechnology ; Combinatorial chemistry ; Radiology ; Organic chemistry ; Physics ; Materials science ; Biochemistry Lanthanide and Transition Metal Complexes ; Radioactive element chemistry and processing ; Advanced MRI Techniques and Applications
Authors: Wenxuan Wang | L. Lu | Ho Pan Bei | Xiangyang Li | Zeyu Du | Manfred F. Maitz | Nan Huang | Qiufen Tu | Xin Zhao | Zhilu Yang
Source: Chemical Engineering Journal (article, 2020-12-28)
Field: Materials Science — Surfaces, Coatings and Films

Self-protonating, plasma polymerized, superimposed multi-layered biomolecule nanoreservoir as blood-contacting surfaces Biomolecule ; Coating ; Biocompatibility ; Surface modification ; Nanotechnology ; Polymerization ; Materials science ; Plasma ; Polymer ; Chemistry ; Organic chemistry Polymer Surface Interaction Studies ; Electrospun Nanofibers in Biomedical Applications ; 3D Printing in Biomedical Research
Authors: Francesco Armillotta | A. Pividori | Matuš Stredansky | Nicola Seriani | Erik Vesselli
Source: Topics in Catalysis (article, 2020-07-22)
Field: Materials Science — Materials Chemistry

Dioxygen at Biomimetic Single Metal-Atom Sites: Stabilization or Activation? The Case of CoTPyP/Au(111) Abstract By means of a combined experimental and computational approach, we show that a 2D metal–organic framework self-assembled at the Au(111) termination is able to mimic the O 2 stabilization and activation mechanisms that are typical of the biochemical environment of proteins and enzymes. 5,10,15,20-tetra(4-pyridyl)21H,23H-porphyrin cobalt(III) chloride (CoTPyP) molecules on Au(111) bind dioxygen forming a covalent bond at the Co center, yielding charge injection into the ligand by exploiting the surface trans-effect. A weakening of the O–O bond occurs, together with the development of a dipole moment, and a change in the molecule’s magnetic moment. Also the bonding geometry is similar to the biological counterpart, with the O 2 molecule sitting on-top of the Co atom and the molecular axis tilted by 118°. The ligand configuration lays between the oxo- and the superoxo-species, in agreement with the observed O–O stretching frequency measured in situ at near-ambient pressure conditions. Chemistry ; Molecule ; Ligand (biochemistry) ; Covalent bond ; Porphyrin ; Metal ; Cobalt ; Catalysis ; Atom (system on chip) ; Crystallography ; Dipole ; Photochemistry ; Stereochemistry ; Inorganic chemistry ; Receptor ; Organic chemistry Porphyrin and Phthalocyanine Chemistry ; Metal-Organic Frameworks: Synthesis and Applications ; Metal complexes synthesis and properties
Authors: Srikrishna Bera | Runze Mao | Xile Hu
Source: ChemRxiv (preprint, 2020-03-27)
Field: Chemistry — Organic Chemistry

Enantioselective C(sp3)–C(sp3) Cross-Coupling of Non-activated Alkyl Electrophiles via Nickel Hydride Catalysis Cross-coupling of two alkyl fragments is an efficient method to produce organic molecules rich in sp&lt;sup&gt;3&lt;/sup&gt;-hydridized carbon centers, which are attractive candidate compounds in drug discovery. Enantioselective C(sp&lt;sup&gt;3&lt;/sup&gt;)-C(sp&lt;sup&gt;3&lt;/sup&gt;) coupling, especially of alkyl electrophiles without an activating group (aryl, vinyl, carbonyl) is challenging. Here we report a strategy based on nickel hydride addition to internal olefins followed by nickel-catalyzed alkyl-alkyl coupling. This strategy enables enantioselective cross-coupling of non-activated alkyl iodides with alkenyl boronates to produce chiral alkyl boronates. Employing readily available and stable olefins as pro-chiral nucleophiles, the coupling proceeds under mild conditions and exhibits broad scope and high functional group tolerance. Applications in late-stage functionalization of natural products and drug molecules, synthesis of chiral building blocks, and enantioselective formal synthesis of (&lt;i&gt;S&lt;/i&gt;)-(+)-Pregabalin are demonstrated.&lt;br&gt; Enantioselective synthesis ; Electrophile ; Alkyl ; Nucleophile ; Chemistry ; Hydride ; Aryl ; Nickel ; Combinatorial chemistry ; Catalysis ; Medicinal chemistry ; Stereochemistry ; Organic chemistry Organoboron and organosilicon chemistry ; Catalytic C–H Functionalization Methods ; Catalytic Cross-Coupling Reactions
Authors: Gabriele Barrera | Federico Scaglione | Matteo Cialone | Federica Celegato | Marco Coïsson | Paola Rizzi | Paola Tiberto
Source: Materials (article, 2020-03-23)
Field: Materials Science — Materials Chemistry

Structural and Magnetic Properties of FePd Thin Film Synthesized by Electrodeposition Method Bimetallic nanomaterials in the form of thin film constituted by magnetic and noble elements show promising properties in different application fields such as catalysts and magnetic driven applications. In order to tailor the chemical and physical properties of these alloys to meet the applications requirements, it is of great importance scientific interest to study the interplay between properties and morphology, surface properties, microstructure, spatial confinement and magnetic features. In this manuscript, FePd thin films are prepared by electrodeposition which is a versatile and widely used technique. Compositional, morphological, surface and magnetic properties are described as a function of deposition time (i.e., film thickness). Chemical etching in hydrochloric acid was used to enhance the surface roughness and help decoupling crystalline grains with direct consequences on to the magnetic properties. X-ray diffraction, SEM/AFM images, contact angle and magnetic measurements have been carried out with the aim of providing a comprehensive characterisation of the fundamental properties of these bimetallic thin films. Materials science ; Thin film ; Microstructure ; Bimetallic strip ; Surface roughness ; Nanotechnology ; Nanomaterials ; Isotropic etching ; Chemical engineering ; Composite material ; Etching (microfabrication) ; Metallurgy ; Layer (electronics) Nanoporous metals and alloys ; Magnetic properties of thin films ; Electrodeposition and Electroless Coatings
Authors: Leonora Podvorica | Enrico Salvadori | Fabrizio Piemontesi | Gianni Vitale | Giampiero Morini | Mario Chiesa
Source: Applied Magnetic Resonance (article, 2020-09-22)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Isolated Ti(III) Species on the Surface of a Pre-active Ziegler Natta Catalyst Abstract The nature of Ti(III) species, introduced in working models of industrial Ziegler Natta catalyst precursors, consisting of MgCl 2 /TiCl 4 binary systems, eventually containing different Lewis basis, are studied by a combination of X- and Q-band CW and pulse EPR spectroscopy. In Ziegler Natta catalysts, Ti(III) play the double role of active catalytic species and unconventional spin probes. On the binary system, two dominant Ti(III) species, characterized by distinctively different EPR spectra, are observed. 35,37 Cl Q-Band HYSCORE spectra allow estimating the hyperfine and nuclear quadrupole interactions of directly coordinated Cl, characterized by a hyperfine dipolar contribution of the order of 5 MHz and nuclear quadrupole interactions of the order of e 2 qQ/h = 9 MHz. Interestingly, the two dominant EPR active species are selectively suppressed by the presence of different Lewis bases, indicating the possibility to address the long standing issue of the influence of Lewis bases in driving specific morphological configurations and influencing the catalytic properties of Ti(III) active sites. Hyperfine structure ; Catalysis ; Electron paramagnetic resonance ; Quadrupole ; Chemistry ; Lewis acids and bases ; Natta ; Spectral line ; Photochemistry ; Physical chemistry ; Nuclear magnetic resonance ; Organic chemistry ; Atomic physics ; Physics ; Polymerization Magnetism in coordination complexes ; Inorganic Chemistry and Materials ; Advanced Battery Materials and Technologies
Authors: Zsófia Császár | József Bakos | Gergely Farkas
Source: Catalysis Letters (article, 2020-02-27)
Field: Chemistry — Inorganic Chemistry

Sulfonated Phosphine Ligands in the Ruthenium Catalyzed Biphasic Hydrogenation of Unsaturated Hydrocarbons Abstract The hydrogenation of monocyclic aromatic hydrocarbons by ruthenium catalysts has been investigated in the presence of sulfonated monophosphine ligands with different stereoelectronic properties under biphasic conditions. The effects of (i) the number of sulfonate groups, (ii) the steric demand of the ligand and (iii) the σ-donor ability of the phosphorus atom have been investigated in the catalytic reactions. The TEM analysis of the catalytically active systems revealed that in situ formed soluble ruthenium nanoparticles (RuNPs) are responsible for the catalytic turnover. The Ru/sulfonated phosphine system with the properly tuned ligand exhibited high activity (8800 h −1 ) and selectivity in the hydrogenation of benzene to cyclohexane. Furthermore, the aqueous phase containing RuNPs could be recycled four times without a considerable loss of activity. Graphic Abstract Chemistry ; Ruthenium ; Catalysis ; Phosphine ; Steric effects ; Cyclohexane ; Ligand (biochemistry) ; Selectivity ; Turnover number ; Noyori asymmetric hydrogenation ; Organometallic chemistry ; Transfer hydrogenation ; Benzene ; Organic chemistry ; Photochemistry ; Medicinal chemistry Asymmetric Hydrogenation and Catalysis ; Nanomaterials for catalytic reactions ; Catalysis for Biomass Conversion
Authors: Sizhe Li | Justyna Jaszczyk | Xavier Pannecoucke | Thomas Poisson | Olivier R. Martin | Cyril Nicolas
Source: Advanced Synthesis & Catalysis (article, 2020-09-25)
Field: Chemistry — Organic Chemistry

Stereospecific Synthesis of Glycoside Mimics Through Migita‐Kosugi‐Stille Cross‐Coupling Reactions of Chemically and Configurationally Stable 1‐<i>C</i>‐Tributylstannyl Iminosugars Abstract A process for the de novo synthesis of imino‐ C ‐glycosides is described. The methodology is based on the reaction of 1‐C‐stannylated iminosugars with various electrophiles under the conditions of Migita‐Kosugi‐Stille cross‐couplings, which gives 1‐C‐substituted iminosugar derivatives in a stereoretentive process. The required iminoglycosyl stannanes are obtained by way of the highly stereoselective addition of tributylstannyllithium to ( S R )‐ or ( S S )‐ N ‐ tert ‐butanesulfinyl glycosylamines, followed by an activation cyclization sequence. Most interestingly, the methodology is tunable: the configuration of the tin adduct is controlled exclusively by the tert ‐butanesulfinyl auxiliary, thus giving access after ring formation to ‘α’‐configured or ‘β’‐configured iminoglycosyl stannanes. With the subsequent stereoretentive C−C bond‐forming process, the methodology allows the synthesis of pseudo anomers of imino‐ C ‐glycosyl compounds in a controlled fashion. magnified image Stille reaction ; Chemistry ; Electrophile ; Iminosugar ; Stereospecificity ; Stereochemistry ; Stereoselectivity ; Anomer ; Glycosyl ; Coupling reaction ; Combinatorial chemistry ; Organic chemistry ; Catalysis Carbohydrate Chemistry and Synthesis ; Glycosylation and Glycoproteins Research ; Fluorine in Organic Chemistry