jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Hassan Sawalha | Theo G. M. van de Ven
Source: Polymer Engineering and Science (article, 2023-11-23)
Field: Materials Science — Biomaterials

Influence of polymer solution composition on the microstructure and thermal and mechanical characteristics of polycaprolactone films Abstract This study investigates the effects of addition of oils and alkanes to the polymer solution on the properties of polycaprolactone (PCL) films. The films were prepared by casting films onto a mold and evaporation in air. Films made without oils showed a dense microstructure. Most of the oils generated porous films, except for cyclohexane and castor oil. The neat PCL and cyclohexane films were stronger than other films, with a tensile strength of about ~11.5 MPa, followed by terpenes (~6.5 MPa) and the weakest films were obtained with hexadecane (~3.5 MPa). The elastic modulus was highest with limonene (~350 MPa), followed by cyclohexane (~150 MPa), and the lowest modulus (~65 MPa) was obtained with castor oil and hexadecane. All films showed high elongation at break (&gt;400%). The degree of crystallinity was the highest with terpenes, whereas the lowest crystallinity was obtained with hexadecane. No significant effect of the oils on the thermal transition temperatures of the films could be observed. In summary, the microstructure and mechanical properties of the PCL films could be effectively fine‐tuned for various applications through the addition of oils and alkanes to the polymer solution. Highlights Oils and alkanes were added to polycaprolactone (PCL) casting solution. PCL films were prepared by casting films onto a mold and evaporation in air. Oils affected the microstructure and mechanical properties of the films. Addition of oils provides a flexible tool to tailor the film properties. PCL films with varying properties could be fabricated for different fields. Materials science ; Polycaprolactone ; Microstructure ; Crystallinity ; Composite material ; Polymer ; Casting ; Ultimate tensile strength ; Hexadecane ; Chemical engineering ; Organic chemistry ; Chemistry biodegradable polymer synthesis and properties ; Electrospun Nanofibers in Biomedical Applications ; Additive Manufacturing and 3D Printing Technologies
Authors: Monika Yadav | Kashmiri Lal | D. Amilan Jose | Vikas D. Ghule | Ram Kumar Tittal
Source: Chemical Papers (article, 2023-04-02)
Field: Chemistry — Organic Chemistry

Synthesis, photophysical and DFT investigations on 1,2,3-triazoles linked to chalcone and chalco-pyrene Chalcone ; Pyrene ; Chemistry ; Triazole ; Proton NMR ; Carbon-13 NMR ; Fluorescence ; Photochemistry ; Click chemistry ; Polar effect ; Stereochemistry ; Organic chemistry Click Chemistry and Applications ; Synthesis and Biological Evaluation ; Synthesis and biological activity
Authors: Emanuele Alberto Slejko | Nicholas Sesto Gorella | R. Gasparini | Nicola Scuor | Stefano Seriani
Source: Polymer Engineering and Science (article, 2023-09-03)
Field: Materials Science — Biomaterials

Tailoring <scp>3D</scp> printed cellulose acetate properties produced via direct ink writing: Densification through over‐extrusion and evaporation rate control Abstract In this study, we conducted a comprehensive experimental campaign aimed at controlling the final properties of 3D printed cellulose acetate. We equipped a commercial printer with a peristaltic pump to be able to print in a continuous fashion by means of the Direct Ink Writing technique. We investigated the effect of ink concentration and printing parameters on the density, mechanical and functional properties of printed objects. Furthermore, water absorption tests demonstrated the hygroscopic behavior of cellulose acetate, with higher water content in samples with lower densities. The diffusion of water within the polymer network followed Fickian diffusion, with the diffusion coefficient influenced by the density of samples. Overall, this study highlights the importance of printing conditions in achieving desired properties in 3D printed cellulose acetate. The ability to fine‐tune the mechanical properties and water absorbance of 3D printed cellulose acetate makes it promising for applications in plant science and bioengineering. Highlights Cellulose acetate has been 3D printed via Direct Ink Writing. The shear‐thinning behavior allows for shape retention during printing. Density of printed samples is strongly controlled by printing parameters. Density of printed parts influences mechanical properties and water absorption. Materials science ; Extrusion ; Cellulose acetate ; Absorption of water ; Inkwell ; 3d printed ; Cellulose ; Composite material ; Absorption (acoustics) ; Absorbance ; Polymer ; Chemical engineering ; Chromatography ; Chemistry ; Biomedical engineering Advanced Cellulose Research Studies ; Additive Manufacturing and 3D Printing Technologies ; Electrospun Nanofibers in Biomedical Applications
Authors: Pengwei Jin | Jun Wu | Rongying Shi | Li Dai | Ying Li
Source: ACS Omega (article, 2023-09-26)
Field: Chemistry — Organic Chemistry

Parabolic Viscosity Behavior of NaCl-Thickened Surfactant Systems upon Temperature Change The viscosity of household care products plays an important role in pleasant delivery using consumer experience at home. A novel solution to mitigate the sharp rising of viscosities at low temperatures of detergents was proposed. By designing the formulation of the surfactant blend, formulators can achieve acceptable viscosity profiles in the temperature range encountered in daily life. The verification and modulation of formulas bearing parabolic viscosity-temperature behavior were systematically studied, including in single, binary, and ternary systems, based on the modulation of sodium ethoxylated alkyl sulfate (AES) by other anions, zwitterions, and nonions. The <i>R</i> ratio theory was used to have a better understanding of the molecular assembly of surfactants behind the parabolic behavior exhibited in rheology analyses. One of the key findings is that the parabolic viscosity-temperature phenomenon could be easily observed in the highly hydrated ethoxylated anionic systems like AES-based systems. For those anions lacking ethoxylation, especially sodium linear alkylbenzene sulfonate (LAS), the monotonic variation of hydration affinity with temperature led to the disappearance of parabola in the observed temperature window (>0 °C). Moreover, salinity played an important role in the hydration affinity of the polar group and the interaction between the hydrophilic headgroups. A balanced salinity should be optimized to modulate the hydration affinity in a desired range so that the parabola could be easily tuned within the target temperature region. These findings provide opportunities for the formulators in the household care industry to design products with better pourability through carefully selecting a combination of surfactants and fine-tuning their ratios to improve consumer use experience, especially in winter. Viscosity ; Pulmonary surfactant ; Rheology ; Ternary operation ; Sulfonate ; Chemistry ; Atmospheric temperature range ; Sodium ; Salinity ; Thermodynamics ; Chemical engineering ; Materials science ; Organic chemistry ; Composite material ; Computer science Surfactants and Colloidal Systems ; Rheology and Fluid Dynamics Studies ; Thermodynamic properties of mixtures
Authors: Celina Bideplán-Moyano | Marcos J. Lo Fiego | Juan José Calmels | Belén Alonso | Gabriel Radivoy | Daniel Ruiz‐Molina | Juan Mancebo‐Aracil | Fabiana Nador
Source: RSC Advances (article, 2023-01-01)
Field: Chemistry — Organic Chemistry

Design and synthesis of unnatural coordination glycopolymer particles (CGPs): unleashing the potential of catechol-saccharide derivatives Our study unveils an innovative methodology that merges catechols with mono- and disaccharides, yielding a diverse array of compounds. This strategic fusion achieves robust yields and introduces ligands with a dual nature: encompassing both the chelating attributes of catechols and the recognition capabilities of carbohydrates. This synergistic design led us to couple one of the novel ligands with an Fe(iii) salt, resulting in the creation of Coordination Glycopolymer Particles (CGPs). These CGPs demonstrate remarkable qualities, boasting outstanding dispersion in both aqueous media and Phosphate Buffered Saline (PBS) solution (pH ∼7.4) at higher concentrations (0.26 mg μL<sup>-1</sup>). Displaying an average Z-size of approximately 55 nm and favourable polydispersity indices (<0.25), these particles exhibit exceptional stability, maintaining their integrity over prolonged periods and temperature variations. Notably, they retain their superior dispersion and stability even when subjected to freezing or heating to 40 °C, making them exceptionally viable for driving biological assays. In contrast to established methods for synthesizing grafted glycopolymers, where typically a glycopolymer is doped with catechol derivatives to create synergy between chelating properties and those inherent to the saccharide, our approach provides a more efficient and versatile pathway for generating CGPs. This involves combining catechols and carbohydrates within a single molecule, enabling the fine-tuning of organic structure from a monomer design step and subsequently transferring these properties to the polymer. Catechol ; Dispersity ; Monomer ; Chemistry ; Polymer ; Aqueous solution ; Chelation ; Denticity ; Dispersion (optics) ; Chemical engineering ; Combinatorial chemistry ; Nanotechnology ; Materials science ; Organic chemistry ; Optics ; Crystal structure Supramolecular Chemistry and Complexes ; Molecular Sensors and Ion Detection ; Advanced Polymer Synthesis and Characterization
Authors: Tero Kämäräinen | Kazunori Kadota | Hiroshi Arima-Osonoi | Hiromasa Uchiyama | Yuichi Tozuka
Source: ACS Biomaterials Science & Engineering (article, 2023-09-25)
Field: Chemistry — Organic Chemistry

Tailoring the Self-Assembly of Steviol Glycoside Nanocarriers with Steroidal Amphiphiles Bile salts are biosurfactants that can induce structure transformations in supramolecular nanoassemblies with conventional surfactants owing to their unique, planar amphiphilic character and the rigidity of their hydrophobic steroid skeleton. However, structural information about the association of bile salts and amphiphilic glycosides is lacking. In this work, we investigated the micelle structure of two anionic di- and trihydroxy bile salts [sodium deoxycholate (SDC) and sodium cholate (SC)] and a conventional anionic surfactant [sodium dodecyl sulfate (SDS)] in mixtures with a nonionic steviol glycoside [α-glucosyl stevia (Stevia-G)] and studied their potential as a nanocarrier system for two poorly water-soluble drugs (clotrimazole and ketoconazole). Decreased critical micelle concentrations determined from surface tension measurements demonstrate synergistic interactions between Stevia-G and SDS/SDC/SC in a decreasing order. Small-angle X-ray and neutron scattering, interpreted by a core-shell ellipsoid model, indicate that SDS and bile salts act differently on the mixed micelle structure. Compared with SDS/Stevia-G, bile salt/Stevia-G had a core-shell structure more similar to that of pure Stevia-G micelles. SDC and SDS had an increasing and decreasing influence, respectively, on the available molecular surface area in mixtures with Stevia-G on the micelle core but a similar influence on the micelle shell solvation number relative to that of their pure micellar structures. The number of bile salt hydroxyl groups was influential in determining the micelle stoichiometry: an increasing number of hydroxyl groups corresponded to decreasing bile salt aggregation numbers and a smaller hydrophobic micellar core. The core volume was the most important structural factor in explaining the drug solubilization capacity of the nanocarrier systems. Therefore, bile salt-steviol glycoside mixed micellar assemblies exhibit structure control mechanisms allowing the fine-tuning of their interior hydrophobic domains important for nanocarrier applications toward solubilization of poorly water-soluble drugs. Micelle ; Chemistry ; Amphiphile ; Critical micelle concentration ; Nanocarriers ; Sodium dodecyl sulfate ; Organic chemistry ; Drug delivery ; Copolymer ; Aqueous solution Surfactants and Colloidal Systems ; Drug Transport and Resistance Mechanisms ; Lipid Membrane Structure and Behavior
Authors: Pedro Henrique Santos-Oliveira | Jefferson Gonçalves Pinheiro Silva | Lars M. Blank | Luiziana Ferreira da Silva | José Gregório Cabrera Gomez
Source: International Journal of Biological Macromolecules (article, 2023-11-21)
Field: Materials Science — Biomaterials

Constant fed-batch cultivation with glucose and propionate as co-substrate: A strategy to fine-tune polyhydroxyalkanoates monomeric composition in Pseudomonas spp. Propionate ; Polyhydroxyalkanoates ; Chemistry ; Composition (language) ; Biochemistry ; Substrate (aquarium) ; Monomer ; Food science ; Bacteria ; Chromatography ; Organic chemistry ; Biology biodegradable polymer synthesis and properties ; Microplastics and Plastic Pollution ; Antimicrobial agents and applications
Authors: Aswin Chandran | Raphaël Ravel‐Massol | Laure Vendier | John M. Slattery | Jason M. Lynam | Mary Grellier
Source: Organometallics (article, 2023-10-19)
Field: Chemistry — Organic Chemistry

Mapping Out the Role of σ-Silane Complexes in the Ruthenium-Catalyzed Hydrosilylation of Nitriles A combined synthetic, mechanistic, and computational study is reported, which provides unique insight into the role of σ-silane complexes in the catalytic hydrosilylation of nitriles. A novel, highly efficient, highly active, and regioselective catalytic monohydrosilylation of aromatic nitriles with secondary silanes using a ruthenium dihydrogen catalyst is reported along with a novel mechanism for hydrosilylation of nitriles. Investigations into the mechanism of this transformation have revealed the influence of σ-Si–H complexes in fine-tuning the selectivity of this hydrosilylation reaction. Displacement of the dihydrogen ligand on the ruthenium precatalyst, ruthenium bis-(dihydrogen) complex [RuH2(η2-H2)2(PCy3)2], 1, by diphenylsilane leads to the formation of new ruthenium σ-Si–H complexes, [RuH2(η2-H2)(η2-HSiHPh2)(PCy3)2], 2, and [RuH2(η3-H2SiPh2)(PCy3)2], 3. Complex 3 reacts readily with benzonitrile leading to hydrosilylation of the nitrile and coordination of the silylimine formed to the ruthenium as a σ-H–Si–N-silylimine complex, [RuH2(η2-HSiPh2NCHPh)(PCy3)2] (4). This systematic investigation of this reactivity led to the discovery of the first direct evidence of an N-silylimine-coordinated ruthenium complex and its involvement in a catalytic hydrosilylation reaction. This led to the discovery of a catalytic protocol for the efficient and selective coupling of secondary silanes with a range of nitriles using 1 as the catalyst. It is proposed that complexes 3 and 4 are key intermediates on the catalytic reaction coordinate, which leads to hydrosilylation of the nitrile. This is supported by DFT calculations along with the observation that 3 and 4 are catalytically active. The Si–N bond formation was found to proceed via direct attack of the nitrile at the silicon atom in 3. Through carefully chosen structural studies and tests of the new ruthenium complexes, along with DFT calculations, the mechanism of the catalytic hydrosilylation of nitriles has been successfully explained. Hydrosilylation ; Ruthenium ; Chemistry ; Nitrile ; Silanes ; Catalysis ; Reactivity (psychology) ; Regioselectivity ; Dihydrogen complex ; Combinatorial chemistry ; Silane ; Photochemistry ; Organic chemistry ; Hydride ; Metal Organoboron and organosilicon chemistry ; Catalytic Cross-Coupling Reactions ; N-Heterocyclic Carbenes in Organic and Inorganic Chemistry
Authors: Nguyen Dang Khang | Cuong Q. Nguyen | Chương V. Nguyen | Chuong V. Nguyen
Source: Advanced Theory and Simulations (article, 2023-12-03)
Field: Materials Science — Materials Chemistry

Achieving Ohmic Contacts in NbS<sub>2</sub>/MoSe<sub>2</sub> van der Waals Heterostructure: A First‐Principles Study Abstract The functionality of electronic and optoelectronic devices relying on two‐dimensional (2D) materials can be substantially influenced by the characteristics of their electrical contacts. Herein, a metal–semiconductor electrical contact between metallic NbS 2 and semiconducting MoSe 2 monolayer is constructed using first‐principles calculations. The electronic properties and contact characteristics of the NbS 2 /MoSe 2 heterostructure as well as the effects of electric fields and in‐plane strains are also explored. These results indicate that the NbS 2 /MoSe 2 heterostructure exhibits the ‐type Schottky contact (ShC) with low Schottky barriers and possesses low contact resistance of the tunneling barrier. Furthermore, the electronic properties and contact characteristics of the NbS 2 /MoSe 2 heterostructure can be fine‐tuned through the application of in‐plane strains and electric fields. The electric fields give rise to the transformation from ‐type to ‐type ShC as well as the conversion from ShC to Ohmic contact (OhC) in the NbS 2 /MoSe 2 heterostructure. Similarly, in‐plane strains play a role in direct‐to‐indirect band gap transitions and further contribute to the conversion from ShC to OhC in the NbS 2 /MoSe 2 heterostructure. These findings offer valuable theoretical insights that can guide the practical utilization of the NbS 2 /MoSe 2 vdW‐MSH in the development of next‐generation electronic and optoelectronic devices. Heterojunction ; Ohmic contact ; Materials science ; Schottky barrier ; Semiconductor ; Optoelectronics ; Monolayer ; Quantum tunnelling ; Schottky diode ; Contact resistance ; Condensed matter physics ; Nanotechnology ; Physics 2D Materials and Applications ; MXene and MAX Phase Materials ; Graphene research and applications
Authors: Rizzqi Septiprajaamalia Rosdianto | Nurul Zakiyah | Rafiqah Nur Viviani | Fortunata Saesarria Deisberanda | Tantri Liris Nareswari | Satrialdi Satrialdi | Irda Fidrianny | Damar Rastri Adhika | William Xaveriano Waresindo | Unang Supratman | Tri Suciati
Source: ACS Omega (article, 2023-04-26)
Field: Materials Science — Materials Chemistry

Novel Insight into Pickering Emulsion and Colloidal Particle Network Construction of Basil Extract for Enhancing Antioxidant and UV-B-Induced Antiaging Activities We developed a facile preparation method of oil-in-water (O/W) Pickering emulsion in an emollient formulation using basil extract (<i>Ocimum americanum</i> L.) as a solid particle stabilizer by fine-tuning the concentration and mixing steps of common cosmetic formulas, such as humectants (hexylene glycol and glycerol), surfactant (Tween 20), and moisturizer (urea). The hydrophobicity of the main phenolic compounds of basil extract (BE), namely, salvigenin, eupatorin, rosmarinic acid, and lariciresinol, supported high interfacial coverage to prevent coalescence of globules. Meanwhile, the presence of carboxyl and hydroxyl groups of these compounds provides active sites for stabilizing the emulsion using urea through the formation of hydrogen bonds. Addition of humectants directed the in situ synthesis of colloidal particles during emulsification. In addition, the presence of Tween 20 can simultaneously reduce the surface tension of the oil but tends to inhibit the adsorption of solid particles at high concentrations, which otherwise formed colloidal particles in water. The level of urea and Tween 20 determined the stabilization system of the O/W emulsion, whether interfacial solid adsorption (Pickering emulsion, PE) or colloidal network (CN). Variation of the partition coefficient of the phenolic compounds present in basil extract facilitated the formation of a mixed PE and CN system with better stability. The addition of excess urea induced interfacial solid particle detachment, which caused the oil droplet enlargement. The choice of stabilization system determined the control of antioxidant activity, diffusion through lipid membranes, and cellular antiaging effects in UV-B-irradiated fibroblasts. Particle sizes of less than 200 nm were found in both stabilization systems, which is beneficial for maximizing their effects. In conclusion, this study provides a technological platform to realize the demand for natural dermal cosmetic and pharmaceutical products with strong antiaging effects. Pickering emulsion ; Chemistry ; Emulsion ; Chemical engineering ; Urea ; Colloid ; Adsorption ; Surface tension ; Organic chemistry ; Membrane ; Particle (ecology) ; Chromatography ; Biochemistry Pickering emulsions and particle stabilization ; Olfactory and Sensory Function Studies ; Advancements in Transdermal Drug Delivery
Authors: Huifang Du | Jian Zhu | Guojun Weng | Jian-jun Li | Xin Li | Jun‐Wu Zhao
Source: Spectrochimica Acta Part A Molecular and Biomolecular Spectroscopy (article, 2023-05-20)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Site-selective growth and plasmonic spectral properties of L-shaped Janus Au-Ag gold nanodumbbells for surface-enhanced Raman scattering Janus ; Materials science ; Plasmon ; Raman scattering ; Discrete dipole approximation ; Nanoparticle ; Nanotechnology ; Raman spectroscopy ; Scattering ; Optics ; Optoelectronics Gold and Silver Nanoparticles Synthesis and Applications ; Pickering emulsions and particle stabilization ; Quantum Dots Synthesis And Properties
Authors: Md Shofiul Alam | Dennys Leyva | Woodline Michelin | Francisco Fernández-Lima | Jaroslava Mikšovská
Source: Physical Chemistry Chemical Physics (article, 2023-01-01)
Field: Chemistry — Spectroscopy

Distinct mechanism of Tb<sup>3+</sup> and Eu<sup>3+</sup> binding to NCS1 Lanthanides have been frequently used as biomimetic compounds for NMR and fluorescence studies of Ca<sup>2+</sup> binding proteins due to having similar physical properties and coordination geometry to Ca<sup>2+</sup> ions. Here we report that a member of the neuronal calcium sensor family, neuronal calcium sensor 1, complexes with two lanthanide ions Tb<sup>3+</sup> and Eu<sup>3+</sup>. The affinity for Tb<sup>3+</sup> is nearly 50 times higher than that for Ca<sup>2+</sup> (<i>K</i><sub>d,Tb<sup>3+</sup></sub> = 0.002 ± 0.0001 μM and <i>K</i><sub>d, Ca<sup>2+</sup></sub> = 91 nM) whereas Eu<sup>3+</sup> binding is notably weaker, <i>K</i><sub>d,Eu<sup>3+</sup></sub> = 26 ± 1 μM. Interestingly, despite having identical charge and similar ionic radii, Tb<sup>3+</sup> and Eu<sup>3+</sup> ions exhibit a distinct binding stoichiometry for NCS1 with one Eu<sup>3+</sup> and two Tb<sup>3+</sup> ions bound per NCS1 monomer, as demonstrated in fluorescence titration and mass spectrometry studies. These results suggest that the lanthanides' affinity for the individual EF hands is fine-tuned by a small variation in the ion charge density as well as EF hand binding loop amino acid sequence. As observed previously for other lanthanide:protein complexes, the emission intensity of Ln<sup>3+</sup> is enhanced upon complexation with the protein, likely due to the displacement of water molecules by oxygen atoms from the coordinating amino acid residues. The overall shape of the Tb<sup>3+</sup>NCS1 and Eu<sup>3+</sup>NCS1 monomer shows high levels of similarity compared to the Ca<sup>2+</sup> bound protein based on their collision cross section. However, the distinct occupation of EF hands impacts NCS1 oligomerization and affinity for the D2R peptide that mimics the NCS1 binding site on the D2R receptor. Specifically, the Tb<sup>3+</sup>NCS1 complex populates the dimer and has comparable affinity for the D2R peptide, whereas Eu<sup>3+</sup> bound NCS1 remains in the monomeric form with a negligible affinity for the D2R peptide. Lanthanide ; Chemistry ; Titration ; Crystallography ; Fluorescence ; EF hand ; Terbium ; Ion ; Binding site ; Monomer ; Calcium ; Inorganic chemistry ; Calcium-binding protein ; Biochemistry Molecular Sensors and Ion Detection ; Ion channel regulation and function ; Neuroscience and Neuropharmacology Research