jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Kalyani Shaji | Stanislav Haviar | P. Zeman | Šimon Kos | R. Čerstvý | Jiří Čapek
Source: Surface and Coatings Technology (article, 2023-12-22)
Field: Materials Science — Materials Chemistry

Controlled sputter deposition of oxide nanoparticles-based composite thin films Materials science ; Nanoparticle ; Composite number ; Deposition (geology) ; Sputter deposition ; Scanning electron microscope ; Thin film ; Chemical engineering ; Monolayer ; Volumetric flow rate ; Nanotechnology ; Sputtering ; Analytical Chemistry (journal) ; Composite material ; Chromatography ; Chemistry ZnO doping and properties ; Gas Sensing Nanomaterials and Sensors ; Copper-based nanomaterials and applications
Authors: Timo Ääritalo | Teija Tirri | Mélanie Aubert | Carl‐Eric Wilén
Source: Polymer Degradation and Stability (article, 2023-03-12)
Field: Materials Science — Polymers and Plastics

Synthesis of silylamine and siloxyamine compounds: A novel approach to flame retardancy of polypropylene and Epoxy resins A series of innovative flame retardants containing N-Si and N-O-Si bonds have been synthesized. Their chemical structures were verified by nuclear magnetic resonance (NMR) spectroscopy and thermal stabilities determined by thermogravimetric analysis (TGA). The results indicate that their thermal and hydrolytic stabilities could be adjusted by fine tuning their silylamine (N-Si) and siloxyamine (N-O-Si) skeletons. Thus, the substituents bonded to the phthalimides, such as diphenylmethylsilyl, dimethylphenylsilyl, diphenyl‑tert-butylsilyl, triisopropylsilyl or diphenylmethylsiloxy; whichever was attached to the imide played a significant role on its thermal and hydrolytic properties. Upon thermal dissociation, the N-Si and N-O-Si compounds were shown to yield aminyl, silyl and oxygen-centered radicals that provided fire proofing effect in polypropylene (PP) films alone and a synergistic effect in combination with conventional phosphorous flame retardant in PP, linear low-density polyethylene (LLDPE) and epoxy resins (EP). Their efficacy as flame retardants alone in thin PP films were evaluated according to the DIN4102-B2 test. Both N-Si and N-O-Si significantly slowed down the burning of PP films. Moreover, their potential as adjuvants with a conventional phosphorous based flame retardant, i.e., spirocyclic phosphonate (AFLAMMIT® PCO 900) in PP and EP resins was evaluated according to the UL-94 V fire standard. A synergistic effect was observed when the phosphorous flame retardant was combined with either N-Si or N-O-SI containing compounds, since none of the flame retardants by themselves could provide V-0 rating in the UL94-V test in PP, LLDPE or EP resins even at much higher loadings. The thermogravimetric analysis carried out under inert atmosphere revealed enhanced and earlier onset of decomposition and thermal activation of phosphorous based flame retardant in the presence of N-Si or N-O-Si in comparison to spirocyclic phosphonate, N-Si or N-O-Si used alone, respectively. The interaction of the phosphorus flame retardant with N-Si was verified by 31P NMR. Fire retardant ; Limiting oxygen index ; Thermogravimetric analysis ; Materials science ; Polypropylene ; Epoxy ; Cone calorimeter ; Polymer chemistry ; Thermal stability ; Imide ; Nuclear chemistry ; Organic chemistry ; Pyrolysis ; Composite material ; Chemistry ; Char Flame retardant materials and properties ; Fire dynamics and safety research ; Synthesis and properties of polymers
Authors: Farzaneh Radmanesh | Alberto Tena | Ernst J. R. Sudhölter | Mark A. Hempenius | Nieck E. Benes
Source: ACS Applied Polymer Materials (article, 2023-02-09)
Field: Materials Science — Polymers and Plastics

Nonaqueous Interfacial Polymerization-Derived Polyphosphazene Films for Sieving or Blocking Hydrogen Gas A series of cyclomatrix polyphosphazene films have been prepared by nonaqueous interfacial polymerization (IP) of small aromatic hydroxyl compounds in a potassium hydroxide dimethylsulfoxide solution and hexachlorocyclotriphosphazene in cyclohexane on top of ceramic supports. Via the amount of dissolved potassium hydroxide, the extent of deprotonation of the aromatic hydroxyl compounds can be changed, in turn affecting the molecular structure and permselective properties of the thin polymer networks ranging from hydrogen/oxygen barriers to membranes with persisting hydrogen permselectivities at high temperatures. Barrier films are obtained with a high potassium hydroxide concentration, revealing permeabilities as low as 9.4 × 10<sup>-17</sup> cm<sup>3</sup> cm cm<sup>-2</sup> s<sup>-1</sup> Pa<sup>-1</sup> for hydrogen and 1.1 × 10<sup>-16</sup> cm<sup>3</sup> cm cm<sup>-2</sup> s<sup>-1</sup> Pa<sup>-1</sup> for oxygen. For films obtained with a lower concentration of potassium hydroxide, single gas permeation experiments reveal a molecular sieving behavior, with a hydrogen permeance of around 10<sup>-8</sup> mol m<sup>-2</sup> s<sup>-1</sup> Pa<sup>-1</sup> and permselectivities of H<sub>2</sub>/N<sub>2</sub> (52.8), H<sub>2</sub>/CH<sub>4</sub> (100), and H<sub>2</sub>/CO<sub>2</sub> (10.1) at 200 °C. Chemistry ; Potassium hydroxide ; Polymerization ; Hydrogen ; Hydroxide ; Permeation ; Polyphosphazene ; Inorganic chemistry ; Oxygen ; Membrane ; Polymer chemistry ; Polymer ; Organic chemistry Synthesis and properties of polymers ; Flame retardant materials and properties ; Membrane Separation and Gas Transport
Authors: Sai Ho Pun | Aidan Delgado | Christina M. Dadich | Adam L. Cronin | Felix R. Fischer
Source: Chem (article, 2023-12-06)
Field: Materials Science — Materials Chemistry

Controlled catalyst-transfer polymerization in graphene nanoribbon synthesis Ribbon ; Materials science ; Scanning tunneling microscope ; Dopant ; Polymerization ; Electronic structure ; Graphene ; Nanotechnology ; Polymer ; Chemical physics ; Graphene nanoribbons ; Chemistry ; Computational chemistry ; Optoelectronics ; Doping ; Composite material Graphene research and applications ; Surface Chemistry and Catalysis ; Molecular Junctions and Nanostructures
Authors: J.J. Torrez-Herrera | S.A. Korili | A. Gil
Source: Powder Technology (article, 2023-09-06)
Field: Chemistry — Inorganic Chemistry

Development of ceramic-MOF filters from aluminum saline slags for capturing CO2 This study describes the procedures followed to synthesize ceramic-MOF filters using aluminum saline slag wastes. Briefly, the raw aluminum saline slags were washed at 80 °C to significantly reduce the saline content and eliminate gases. The pretreated material was mixed with glucose (G/S ratios between 0.2 and 1.6) and acetone by stirring for 4 h. After this time, the resulting solid was dried at 60 °C and then at 190 °C. During the glucose caramelization step, PegMn400 was also added and the temperature increased to 1200 °C. The obtained solid was impregnated with precursor solutions to achieve a supported ZIF-8 MOF. The ceramic-MOF filters were characterized by X-ray diffraction (XRD), N2 adsorption at 77 K, X-ray fluorescence (XRF), scanning electron microscopy (SEM) and transmission electron microscopy (HR-TEM), thereby confirming the presence of a structure that allows dispersion of the synthesized and supported ZIF-8. Finally, the performance of these ceramic-MOF filters as CO2 adsorbents was evaluated in the temperature range 50–300 °C, with isosteric heats of 19 kJ/mol being obtained using the Clausius-Clapeyron equation. Scanning electron microscope ; Ceramic ; Adsorption ; Transmission electron microscopy ; Chemistry ; Materials science ; Acetone ; Aluminium ; Analytical Chemistry (journal) ; Chemical engineering ; Nuclear chemistry ; Chromatography ; Metallurgy ; Composite material ; Nanotechnology ; Organic chemistry Metal-Organic Frameworks: Synthesis and Applications ; Membrane Separation and Gas Transport ; Industrial Gas Emission Control
Authors: Rodrigo Calvo | Isabel Rodriguez Mariblanca | Valerio Pini | Monica Dias | Virginia Cebrián | Andreas Thon | Asís Saad | Antonio Salvador-Mátar | Óscar Ahumada | Miguel Manso‐Silván | Aaron E. Saunders | Wentao Wang | Adonis Stassinopoulos
Source: Nanomaterials (article, 2023-11-11)
Field: Materials Science — Biomaterials

Novel Characterization Techniques for Multifunctional Plasmonic–Magnetic Nanoparticles in Biomedical Applications In the rapidly emerging field of biomedical applications, multifunctional nanoparticles, especially those containing magnetic and plasmonic components, have gained significant attention due to their combined properties. These hybrid systems, often composed of iron oxide and gold, provide both magnetic and optical functionalities and offer promising avenues for applications in multimodal bioimaging, hyperthermal therapies, and magnetically driven selective delivery. This paper focuses on the implementation of advanced characterization methods, comparing statistical analyses of individual multifunctional particle properties with macroscopic properties as a way of fine-tuning synthetic methodologies for their fabrication methods. Special emphasis is placed on the size-dependent properties, biocompatibility, and challenges that can arise from this versatile nanometric system. In order to ensure the quality and applicability of these particles, various novel methods for characterizing the magnetic gold particles, including the analysis of their morphology, optical response, and magnetic response, are also discussed, with the overall goal of optimizing the fabrication of this complex system and thus enhancing its potential as a preferred diagnostic agent. Nanotechnology ; Materials science ; Characterization (materials science) ; Magnetic nanoparticles ; Plasmon ; Biocompatibility ; Fabrication ; Nanoparticle ; Iron oxide nanoparticles ; Computer science ; Optoelectronics Nanoparticle-Based Drug Delivery ; Characterization and Applications of Magnetic Nanoparticles ; Iron oxide chemistry and applications
Authors: Ruxandra G. Chitac | Vladimir L. Zholobenko | Robin S. Fletcher | Emma Softley | Jonathan P. Bradley | Álvaro Mayoral | Alessandro Turrina | Paul A. Wright
Source: Journal of the American Chemical Society (article, 2023-09-27)
Field: Chemistry — Inorganic Chemistry

Synthetic Control of the Defect Structure and Hierarchical Extra-Large-/Small-Pore Microporosity in Aluminosilicate Zeolite SWY The SWY-type aluminosilicate zeolite, STA-30, has been synthesized via different routes to understand its defect chemistry and solid acidity. The synthetic parameters varied were the gel aging, the Al source, and the organic structure directing agent. All syntheses give crystalline materials with similar Si/Al ratios (6-7) that are stable in the activated K,H-form and closely similar by powder X-ray diffraction. However, they exhibit major differences in the crystal morphology and in their intracrystalline porosity and silanol concentrations. The diDABCO-C8<sup>2+</sup> (1,1'-(octane-1,8-diyl)bis(1,4-diazabicyclo[2.2.2]octan)-1-ium)-templated STA-30 samples (but not those templated by bisquinuclidinium octane, diQuin-C8<sup>2+</sup>) possess hierarchical microporosity, consisting of noncrystallographic extra-large micropores (13 Å) that connect with the characteristic <i>swy</i> and <i>gme</i> cages of the SWY structure. This results in pore volumes up to 30% greater than those measured in activated diQuin-C8_STA-30 as well as higher concentrations of silanols and fewer Brønsted acid sites (BASs). The hierarchical porosity is demonstrated by isopentane adsorption and the FTIR of adsorbed pyridine, which shows that up to 77% of the BASs are accessible (remarkable for a zeolite that has a small-pore crystal structure). A structural model of single <i>can</i>/<i>d6r</i> column vacancies is proposed for the extra-large micropores, which is revealed unambiguously by high-resolution scanning transmission electron microscopy. STA-30 can therefore be prepared as a hierarchically porous zeolite via direct synthesis. The additional noncrystallographic porosity and, subsequently, the amount of SiOHs in the zeolites can be enhanced or strongly reduced by the choice of crystallization conditions. Zeolite ; Chemistry ; Microporous material ; Aluminosilicate ; Silanol ; Porosity ; Octane ; Crystallography ; Sodalite ; Chemical engineering ; Crystal structure ; Molecular sieve ; Adsorption ; Powder diffraction ; Mesoporous material ; Mineralogy ; Organic chemistry ; Catalysis Zeolite Catalysis and Synthesis ; Mesoporous Materials and Catalysis ; Chemical Synthesis and Characterization
Authors: Marianna V. Kharlamova | Christian Kramberger
Source: Nanomaterials (review, 2023-02-19)
Field: Materials Science — Materials Chemistry

Metallocene-Filled Single-Walled Carbon Nanotube Hybrids In this paper, the growth mechanism, structure, growth processes, growth kinetics, and optical, vibronic and electronic properties of metallocene-filled single-walled carbon nanotubes (SWCNTs) are considered. A description of the procedures used to fill the nanotubes is provided. An investigation of doping effects on metallicity-mixed SWCNTs filled with metallocenes by Raman spectroscopy, near edge X-ray absorption fine structure spectroscopy, photoemission spectroscopy, and optical absorption spectroscopy is described. The studies of doping effects on metallicity-sorted SWCNTs filled with metallocenes are discussed. Doping effects in metallicity-mixed and sorted SWCNTs upon the chemical transformation of encapsulated molecules are analyzed. A discussion of the modification of the electronic properties of filled SWCNTs is presented. Applications of metallocene-filled SWCNTs in electrochemistry, thermoelectric power generation, chemical sensors, and magnetic recording are discussed. Materials science ; Carbon nanotube ; Raman spectroscopy ; Doping ; Metallocene ; Absorption spectroscopy ; Spectroscopy ; Selective chemistry of single-walled nanotubes ; Nanotechnology ; Optical properties of carbon nanotubes ; Thermoelectric effect ; Chemical engineering ; Nanotube ; Absorption (acoustics) ; Composite material ; Optoelectronics ; Polymerization ; Polymer ; Optics Carbon Nanotubes in Composites ; Graphene research and applications ; Force Microscopy Techniques and Applications
Authors: Alexander J. Menke | Camryn J. Gloor | Liam E. Claton | Magy A. Mekhail | Hongjun Pan | Mikaela D. Stewart | Kayla N. Green | Joseph H. Reibenspies | Giovanni M. Pavan | Riccardo Capelli | Eric E. Simanek
Source: The Journal of Organic Chemistry (article, 2023-02-13)
Field: Chemistry — Organic Chemistry

A Model for the Rapid Assessment of Solution Structures for 24-Atom Macrocycles: The Impact of β-Branched Amino Acids on Conformation Experiment and computation are used to develop a model to rapidly predict solution structures of macrocycles sharing the same Murcko framework. These 24-atom triazine macrocycles result from the quantitative dimerization of identical monomers presenting a hydrazine group and an acetal tethered to an amino acid linker. Monomers comprising glycine and the β-branched amino acids threonine, valine, and isoleucine yield macrocycles <b>G-G</b>, <b>T-T</b>, <b>V-V</b>, and <b>I-I</b>, respectively. Elements common to all members of the framework include the efficiency of macrocyclization (quantitative), the solution- and solid-state structures (folded), the site of protonation (opposite the auxiliary dimethylamine group), the geometry of the hydrazone (<i>E</i>), the C2 symmetry of the subunits (conserved), and the rotamer state adopted. In aggregate, the data reveal metrics predictive of the three-dimensional solution structure that derive from the fingerprint region of the 1D <sup>1</sup>H spectrum and a network of rOes from a single resonance. The metrics also afford delineation of more nuanced structural features that allow subpopulations to be identified among the members of the framework. Well-tempered metadynamics provides free energy surfaces and population distributions of these macrocycles. The areas of the free energy surface decrease with increasing steric bulk (<b>G-G</b> > <b>V-V</b> ∼ <b>T-T</b> > <b>I-I</b>). In addition, the surfaces are increasingly isoenergetic with decreasing steric bulk (<b>G-G</b> > <b>V-V</b> ∼ <b>T-T</b> > <b>I-I</b>). Chemistry ; Steric effects ; Conformational isomerism ; Stereochemistry ; Metadynamics ; Crystallography ; Protonation ; Computational chemistry ; Molecular dynamics ; Molecule ; Organic chemistry Chemical Reaction Mechanisms ; DNA and Nucleic Acid Chemistry ; Chemical Synthesis and Analysis
Authors: Jie Liu | Ying Zhang | Kim van Dongen | Chris J. Kennedy | Maaike J. G. Schotman | Patricia P. Marín San Román | Cornelis Storm | Patricia Y. W. Dankers | Rint P. Sijbesma
Source: Biomacromolecules (article, 2023-05-29)
Field: Materials Science — Biomaterials

Hepatic Spheroid Formation on Carbohydrate-Functionalized Supramolecular Hydrogels Two synthetic supramolecular hydrogels, formed from bis-urea amphiphiles containing lactobionic acid (LBA) and maltobionic acid (MBA) bioactive ligands, are applied as cell culture matrices <i>in vitro</i>. Their fibrillary and dynamic nature mimics essential features of the extracellular matrix (ECM). The carbohydrate amphiphiles self-assemble into long supramolecular fibers in water, and hydrogels are formed by physical entanglement of fibers through bundling. Gels of both amphiphiles exhibit good self-healing behavior, but remarkably different stiffnesses. They display excellent bioactive properties in hepatic cell cultures. Both carbohydrate ligands used are proposed to bind to asialoglycoprotein receptors (ASGPRs) in hepatic cells, thus inducing spheroid formation when seeding hepatic HepG2 cells on both supramolecular hydrogels. Ligand nature, ligand density, and hydrogel stiffness influence cell migration and spheroid size and number. The results illustrate the potential of self-assembled, carbohydrate-functionalized hydrogels as matrices for liver tissue engineering. Self-healing hydrogels ; Asialoglycoprotein receptor ; Supramolecular chemistry ; Chemistry ; Biophysics ; Amphiphile ; Extracellular matrix ; Tissue engineering ; In vitro ; Biochemistry ; Polymer chemistry ; Copolymer ; Polymer ; Organic chemistry ; Molecule ; Biomedical engineering ; Biology Supramolecular Self-Assembly in Materials ; Proteoglycans and glycosaminoglycans research ; Glycosylation and Glycoproteins Research
Authors: М. А. Gorbunova | Denis V. Anokhin | Ainur F. Abukaev | Dimitri A. Ivanov
Source: Crystals (article, 2023-09-28)
Field: Materials Science — Polymers and Plastics

Impact of Soft Segment Composition on Phase Separation and Crystallization of Multi-Block Thermoplastic Polyurethanes Based on Poly(butylene adipate) Diol and Polycaprolactone Diol In this work, we explore the influence of soft segment structure on the crystallinity and phase separation of semicrystalline multi-block thermoplastic polyurethanes (TPUs) based on poly(butylene adipate) diol, polycaprolactone diol, and their mixture. According to thermal and structural analyses, the crystal growth rate and degree of crystallinity decrease with an increase in the PCL/PBA ratio and reach a minimum at the equimolar composition of polyesters. A reduction in crystal phase content leads to an improvement in elastomeric behavior. TPU samples with high PCL content demonstrate enhanced crystallinity but a lower melting temperature compared to TPU with PBA crystals. Crystallization of TPU below room temperature results in an enhancement of total crystallinity and a change in the phase composition of the PBA block. The difference in semicrystalline morphology and crystallization kinetics can be explained by the efficiency of phase separation and the density of hydrogen bonding between soft and hard segments. Our findings show that the ratio of the two crystallizable polyesters, combined with the choice of crystallization temperature, allows for independent control over the melting temperature and the overall degree of crystallinity of the TPUs. This significantly impacts the mechanical characteristics of the materials. The effect of adding a second crystallizable polyester on the crystallization behavior, phase composition, and mechanical properties of TPU is discussed for the first time. Crystallinity ; Materials science ; Crystallization ; Adipate ; Polycaprolactone ; Polyester ; Chemical engineering ; Phase (matter) ; Thermoplastic polyurethane ; Thermoplastic ; Composite material ; Polymer chemistry ; Elastomer ; Polymer ; Organic chemistry ; Chemistry Polymer composites and self-healing ; Polymer Nanocomposites and Properties ; Polymer crystallization and properties
Authors: Paul Hoschtettler | Guillaume Pickaert | Alain Carvalho | Marie‐Christine Averlant‐Petit | Loïc Stefan
Source: Chemistry of Materials (article, 2023-05-17)
Field: Materials Science — Biomaterials

Highly Synergistic Properties of Multicomponent Hydrogels Thanks to Cooperative Nucleopeptide Assemblies Supramolecular materials have drawn much attention in the past years, particularly because of their great versatility in terms of structures, organization, and types of nano-objects they can form. Among them, amino acid and peptide derivatives are biomolecules extensively used thanks to their inherent properties and applicability for biological and health applications. Their exceptional abilities to self-assemble have been harnessed to create a myriad of objects and materials, including hydrogels. However, the use of one and only one molecule (i.e., monocomponent) is the widely reported approach which is of great interest in terms of simplicity of use, but it has numerous limitations in terms of properties. To tackle these issues, the multicomponent approach is a promising strategy, even if challenging, for designing low-molecular-weight molecules able to interact with each other to create new assemblies and new properties not achievable with a single compound. In this context, we report herein on the design, synthesis, and multiscale analysis of an original series of nucleopeptides, i.e., comprising both peptide and DNA-nucleobase moieties linked covalently. Thanks to their dual nature, these nucleopeptides are able to co-assemble when complementary nucleobase moieties interact intermolecularly via hydrogen bonding and π-stacking interactions, leading to impressive synergistic effects, which result in mechanical properties improved by more than 270,000% (with stiffness up to >700 kPa) and self-assembly abilities by ∼280%. To decipher the structure/property relationships, a comprehensive multiscale analysis approach (including rheology, fluorescence, cryo-scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, circular dichroism, nuclear magnetic resonance, and high-resolution magic angle spinning) has been carried out to understand the impact of nucleobases on the supramolecular assembly process and the subsequent formation of nanoobjects, three-dimensional architectures of the hydrogel scaffold, and the resulting physicochemical and mechanical properties of these highly synergistic nucleopeptide assemblies. Biomolecule ; Supramolecular chemistry ; Stacking ; Nucleobase ; Self-healing hydrogels ; Nanotechnology ; Context (archaeology) ; Chemistry ; Molecule ; Materials science ; Hydrogen bond ; Combinatorial chemistry ; DNA ; Organic chemistry Supramolecular Self-Assembly in Materials ; RNA Interference and Gene Delivery ; Chemical Synthesis and Analysis