jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Celia Martín-Morales | Jorge Fernández Méndez | Pîlar Aranda | Eduardo Ruiz‐Hitzky
Source: Beilstein Journal of Nanotechnology (article, 2023-04-25)
Field: Materials Science — Biomaterials

Nanoarchitectonics to entrap living cells in silica-based systems: encapsulations with yolk–shell and sepiolite nanomaterials In the present work, the bottom-up fabrication of biohybrid materials using a nanoarchitectonics approach has been applied to entrap living cells. Unicellular microorganisms, that is, cyanobacteria and yeast cells, have been immobilized in silica and silicate-based substrates organized as nanostructured materials. In a first attempt, matrices based on bionanocomposites of chitosan and alginate incorporating sepiolite clay mineral and shaped as films, beads, or foams have been explored for the immobilization of cyanobacteria. It has been observed that this type of biohybrid substrates leads to serious problems regarding the long-time survival of the encapsulated microorganisms. Alternative procedures using silica-based matrices with low sodium content, generated by sol-gel methods, as well as pre-synthesised yolk-shell bionanohybrids have been studied subsequently. Optical microscopy and SEM confirm that the silica shell microstructures provide a reduced contact between cells. The inorganic matrix increases the survival of the cells and maintains their bioactivity. Thus, the encapsulation efficiency is improved compared to the approach using a direct contact of cells in a silica matrix. Encapsulated yeast produced ethanol over a period of several days, pointing out the useful biocatalytic potential of the approach and suggesting further optimization of the present protocols. Sepiolite ; Materials science ; Nanomaterials ; Chitosan ; Chemical engineering ; Sodium silicate ; Nanotechnology ; Silicon dioxide ; Yeast ; Chemistry ; Composite material ; Organic chemistry Diatoms and Algae Research ; Biocrusts and Microbial Ecology ; Algal biology and biofuel production
Authors: Nina S. Bukhtiiarova | Alberto Credi | Stefano Corrà
Source: Chemical Communications (article, 2023-01-01)
Field: Chemistry — Organic Chemistry

Controlling molecular shuttling in a rotaxane with weak ring recognition sites We describe a rotaxane molecular shuttle encompassing triazolium and tertiary ammonium units as weak recognition sites for the ring. Such a design, which differs from that of typical controllable rotaxanes, allows the precise tuning of the ring distribution among the two sites - <i>i.e.</i>, the coconformational equilibrium - by changing the solvent polarity or the nature of the counteranions. Shuttling of the ring between the two stations can also be toggled by acid-base stimuli. Such an approach is paradigmatic to obtain rotaxanes that can sense environmental changes and transduce them into a coconformational response and opens avenues for novel applications in sensing and stimuli-responsive materials. Rotaxane ; Bistability ; Solvent polarity ; Polarity (international relations) ; Chemistry ; Ring (chemistry) ; Molecular recognition ; Solvent ; Molecular switch ; Chemical physics ; Pairing ; Molecule ; Materials science ; Supramolecular chemistry ; Physics ; Optoelectronics ; Organic chemistry Supramolecular Chemistry and Complexes ; Molecular Sensors and Ion Detection ; Photoreceptor and optogenetics research
Authors: Xiao Zhao | Zoriana Demchuk | Jia Tian | Jiancheng Luo | Bingrui Li | Ke Cao | Alexei P. Sokolov | Diana Hun | Tomonori Saito | Pengfei Cao
Source: Materials Horizons (article, 2023-12-06)
Field: Materials Science — Polymers and Plastics

Ductile adhesive elastomers with force-triggered ultra-high adhesion strength Elastomers play a vital role in many forthcoming advanced technologies in which their adhesive properties determine materials' interface performance. Despite great success in improving the adhesive properties of elastomers, permanent adhesives tend to stick to the surfaces prematurely or result in poor contact depending on the installation method. Thus, elastomers with on-demand adhesion that is not limited to being triggered by UV light or heat, which may not be practical for scenarios that do not allow an additional external source, provide a solution to various challenges in conventional adhesive elastomers. Herein, we report a novel, ready-to-use, ultra high-strength, ductile adhesive elastomer with an on-demand adhesion feature that can be easily triggered by a compression force. The precursor is mainly composed of a capsule-separated, two-component curing system. After a force-trigger and curing process, the ductile adhesive elastomer exhibits a peel strength and a lap shear strength of 1.2 × 10<sup>4</sup> N m<sup>-1</sup> and 7.8 × 10<sup>3</sup> kPa, respectively, which exceed the reported values for advanced ductile adhesive elastomers. The ultra-high adhesion force is attributed to the excellent surface contact of the liquid-like precursor and to the high elastic modulus of the cured elastomer that is reinforced by a two-phase design. Incorporation of such on-demand adhesion into an elastomer enables a controlled delay between installation and curing so that these can take place under their individual ideal conditions, effectively reducing the energy cost, preventing failures, and improving installation processes. Materials science ; Adhesive ; Elastomer ; Composite material ; Adhesion Polymer composites and self-healing ; Surface Modification and Superhydrophobicity ; Polymer Nanocomposites and Properties
Authors: Angelica Bartoletti | Inês Soares | A.M. Ramos | Yvonne Shashoua | Anita Quye | Teresa Casimiro | Joana Lia Ferreira
Source: Polymers (article, 2023-01-21)
Field: Materials Science — Polymers and Plastics

Assessing the Impact and Suitability of Dense Carbon Dioxide as a Green Solvent for the Treatment of PMMA of Historical Value Surface cleaning of plastic materials of historical value can be challenging due to the high risk of inducing detrimental effects and visual alterations. As a result, recent studies have focused on researching new approaches that might reduce the associated hazards and, at the same time, minimize the environmental impact by employing biodegradable and green materials. In this context, the present work investigates the effects and potential suitability of dense carbon dioxide (CO<sub>2</sub>) as an alternative and green solvent for cleaning plastic materials of historical value. The results of extensive trials with CO<sub>2</sub> in different phases (supercritical, liquid, and vapor) and under various conditions (pressure, temperature, exposure, and depressurization time) are reported for new, transparent, thick poly(methyl methacrylate) (PMMA) samples. The impact of CO<sub>2</sub> on the weight, the appearance of the samples (dimensions, color, gloss, and surface texture), and modifications to their physicochemical and mechanical properties were monitored via a multi-analytical approach that included optical microscopy, Raman and attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopies, and micro-indentation (Vickers hardness). Results showed that CO<sub>2</sub> induced undesirable and irreversible changes in PMMA samples (i.e., formation of fractures and stress-induced cracking, drastic decrease in the surface hardness of the samples), independent of the conditions used (i.e., temperature, pressure, CO<sub>2</sub> phase, and exposure time). Carbon dioxide ; Solvent ; Value (mathematics) ; Materials science ; Environmental science ; Environmental chemistry ; Chemical engineering ; Chemistry ; Organic chemistry ; Mathematics ; Statistics ; Engineering Polymer Foaming and Composites ; Phase Equilibria and Thermodynamics ; Adsorption, diffusion, and thermodynamic properties of materials
Authors: Ricardo Ballinas-Indilí | María Inés Nicolás‐Vázquez | Joel Martínez | María Teresa Ramírez‐Apán | Cecilio Ãlvarez-Toledano | Rubén A. Toscano | Maricarmen Hernández‐Rodríguez | Elvia Mera Jiménez | René Miranda
Source: International Journal of Molecular Sciences (article, 2023-10-21)
Field: Chemistry — Organic Chemistry

Synthesis, Cytotoxic Activity and In Silico Study of Novel Dihydropyridine Carboxylic Acids Derivatives To aid the possible prevention of multidrug resistance in tumors and cause lower toxicity, a set of sixteen novel dihydropyridine carboxylic acids derivatives <b>3a-p</b> were produced; thus, the activation of various ynones with triflic anhydride was performed, involving a nucleophilic addition of several <i>bis</i>(trimethylsilyl) ketene acetals, achieving good yields requiring easy workup. The target molecules were unequivocally characterized by common spectroscopic methods. In addition, two of the tested compounds (<b>3a</b>, and <b>3b</b>) were selected to perform in silico studies due to the highest cytotoxic activity towards the HCT-15 cell line (7.94 ± 1.6 μM and 9.24 ± 0.9 μM, respectively). Employing theoretical calculations with density functional theory (DFT) using the B3LYP/6-311++G(d,p) showed that the molecular parameters correlate adequately with the experimental results. In contrast, predictions employing Osiris Property Explorer showed that compounds <b>3a</b> and <b>3b</b> present physicochemical characteristics that would likely make it an orally active drug. Moreover, the performance of Docking studies with proteins related to the apoptosis pathway allowed a proposal of which compounds could interact with PARP-1 protein. Pondering the obtained results (synthesis, in silico, and cytotoxic activity) of the target compounds, they can be judged as suitable antineoplastic agent candidates. In silico ; Chemistry ; Combinatorial chemistry ; Docking (animal) ; Trimethylsilyl ; Nucleophile ; Multiple drug resistance ; Cytotoxic T cell ; Stereochemistry ; Lipinski's rule of five ; Molecule ; Cytotoxicity ; Density functional theory ; Biochemistry ; Computational chemistry ; Medicinal chemistry ; Organic chemistry ; In vitro ; Antibiotics Synthesis and biological activity ; Multicomponent Synthesis of Heterocycles ; Synthesis of heterocyclic compounds
Authors: Yanwei Gu | Herdya S. Torchon | Yikun Zhu | Zheng Wei | Dieter Schollmeyer | Manfred Wagner | Yong Ni | Zehua Wu | Hao Wu | Yazhou Zhou | Zijie Qiu | Marina A. Petrukhina | Kläus Müllen
Source: Angewandte Chemie International Edition (article, 2023-06-27)
Field: Chemistry — Organic Chemistry

Twisted Diindeno‐Fused Dibenzo[<i>a</i>,<i>h</i>]anthracene Derivatives and their Dianions We report a facile synthesis of diindeno-fused dibenzo[a,h]anthracene derivatives (DIDBA-2Cl, DIDBA-2Ph, and DIDBA-2H) with different degrees of non-planarity using three substituents (chloro, phenyl, and hydrogen) of various sizes. The planarization of their cores, as evidenced by the decreased end-to-end torsional angles, was confirmed by X-ray crystallography. Their enhanced energy gaps with twisting were investigated by a combination of spectroscopic and electrochemical methods with density functional theory, which showed a transition from singlet open-shell to closed-shell configuration. Moreover, their doubly reduced states, DIDBA-2Ph<sup>2-</sup> and DIDBA-2H<sup>2-</sup> , were achieved by chemical reduction. The structures of dianions were identified by X-ray crystallographic analysis, which elucidated that the electron charging further distorted the backbones. The electronic structure of the dianions was demonstrated by experimental and theoretical approaches, suggesting decreased energy gaps with larger non-planarity, different from the neutral species. Planarity testing ; Anthracene ; Density functional theory ; Chemistry ; Singlet state ; Chemical-mechanical planarization ; Electrochemistry ; Crystallography ; Computational chemistry ; Photochemistry ; Physical chemistry ; Atomic physics ; Excited state ; Physics ; Organic chemistry Synthesis and Properties of Aromatic Compounds ; Porphyrin and Phthalocyanine Chemistry ; Luminescence and Fluorescent Materials
Authors: Christo N. Nanev | Emmanuel Saridakis | Naomi E. Chayen
Source: International Journal of Molecular Sciences (article, 2023-11-15)
Field: Materials Science — Materials Chemistry

Growing Crystals for X-ray Free-Electron Laser Structural Studies of Biomolecules and Their Complexes Currently, X-ray crystallography, which typically uses synchrotron sources, remains the dominant method for structural determination of proteins and other biomolecules. However, small protein crystals do not provide sufficiently high-resolution diffraction patterns and suffer radiation damage; therefore, conventional X-ray crystallography needs larger protein crystals. The burgeoning method of serial crystallography using X-ray free-electron lasers (XFELs) avoids these challenges: it affords excellent structural data from weakly diffracting objects, including tiny crystals. An XFEL is implemented by irradiating microjets of suspensions of microcrystals with very intense X-ray beams. However, while the method for creating microcrystalline microjets is well established, little attention is given to the growth of high-quality nano/microcrystals suitable for XFEL experiments. In this study, in order to assist the growth of such crystals, we calculate the mean crystal size and the time needed to grow crystals to the desired size in batch crystallization (the predominant method for preparing the required microcrystalline slurries); this time is reckoned theoretically both for microcrystals and for crystals larger than the upper limit of the Gibbs-Thomson effect. The impact of the omnipresent impurities on the growth of microcrystals is also considered quantitatively. Experiments, performed with the model protein lysozyme, support the theoretical predictions. Biomolecule ; Free-electron laser ; Crystallography ; Laser ; X-ray ; Chemistry ; Materials science ; Nanotechnology ; Optics ; Physics Enzyme Structure and Function ; Advanced X-ray Imaging Techniques ; Advanced Electron Microscopy Techniques and Applications
Authors: Daniele Schiavi | Anna Rita Taddei | Giorgio Mariano Balestra
Source: Horticulturae (article, 2023-04-23)
Field: Materials Science — Biomaterials

Investigating Cellulose Nanocrystals’ Biocompatibility and Their Effects on Pseudomonas syringae pv. tomato Epiphytic Survival for Sustainable Crop Protection Nanotechnology could play a huge role in ensuring safer and greener agriculture in the years ahead by providing sustainable tools to control plant diseases. In this study, the possibility of using cellulose nanocrystals (CNCs) obtained from tomato waste to control the bacterial speck disease’s causal agent was evaluated for the effects on plant development. Biocompatibility was assessed by studying seeds’ germination, leaf area, biomass and nitrogen balance index of tomato seedlings treated with CNC. Since epiphytic survival represents a relevant phase in early and later infections provoked by Pseudomonas syringae pv. tomato (Pst), the CNC’s ability to lower the level of bacterial cells in the plant canopy was evaluated in treated seedlings at 1, 7 and 14 days after being artificially inoculated. Leaflets were collected and washed to quantify the epiphytic bacterial population and observed through electron microscopy. Obtained results indicate that CNCs are non-toxic, compatible nanomaterials, highlighting at the same time their potential in counteracting bacterial speck disease by decreasing the level of epiphytic population after two weeks from inoculation by up to one log unit (3.08 CFU cm−2) compared to the control (3.94 CFU cm−2). Moreover, we were able to demonstrate that it is possible to cut in half the amount of copper without losing effectiveness in controlling the bacteria by mixing it with CNCs, concluding that CNCs could be used to design innovative sustainable plant protection strategies. Epiphyte ; Pseudomonas syringae ; Population ; Biocompatibility ; Inoculation ; Horticulture ; Biology ; Pseudomonas ; Crop ; Biomass (ecology) ; Agronomy ; Botany ; Chemistry ; Bacteria ; Medicine Advanced Cellulose Research Studies ; Polysaccharides and Plant Cell Walls ; Plant-Microbe Interactions and Immunity
Authors: Sudesh Mallick | Kalidass Kollimalaian | Prabhakar Chetti | Parthasarathy Venkatakrishnan
Source: Chemistry - A European Journal (article, 2023-09-25)
Field: Chemistry — Organic Chemistry

Chasing Turns and Twists: Unraveling the One‐Step Synthesis, Intricate Pathways, and Structural Revelations of <i>N</i>‐Aryl Aza‐quasi[8]circulenes An efficient one-step synthesis of N-Aryl aza-quasi[8]circulenes is reported starting from bis(biaryl)carbazoles. The intermediacy of N-aryl aza[7]helicene is investigated, and the Scholl oxidative cyclization route is invoked here to overcome the large strain during the formation of N-aryl aza-quasi[8]circulenes from N-aryl aza[7]helicene. Notably, this transformation occurs without the need for directing groups and proceeds from a more helical to a less helical pathway. Both the N-aryl aza[7]helicene and N-aryl aza-quasi[8]circulene are confirmed by single crystal X-ray structural analysis. The enantiomers of N-aryl aza[7]helicene are separated by chiral HPLC and analyzed by circular dichroism spectroscopy to investigate their chiroptical properties. However, N-aryl aza-quasi[8]circulene racemizes rapidly. The radical cations generated from aza-quasi[8]circulene through chemical oxidation exhibit broad absorption in the near-IR region and air stability up to 24 h. Optical and electrochemical studies with aza[7]helicene and aza-quasi[8]circulene derivatives highlight their potential in organic electronic devices. Helicene ; Aryl ; Circular dichroism ; Chemistry ; Enantiomer ; Stereochemistry ; Crystallography ; Molecule ; Organic chemistry Synthesis and Properties of Aromatic Compounds ; Advanced NMR Techniques and Applications ; Porphyrin and Phthalocyanine Chemistry
Authors: Mert Dinc | Eda Ismailoglu | Zeynep Mert | Kerem Kaya | Melda Tayanc | Baris Yücel
Source: Organic Letters (article, 2023-05-26)
Field: Chemistry — Organic Chemistry

Base-Mediated Rearrangement of α-Dithioacetyl Propargylamines via Expansion of Dithioacetyl Ring: Synthesis of Medium-Sized <i>S,S</i>-Heterocycles Base-mediated rearrangement of 1,3-dithianyl-substituted propargylamines in DMF via expansion of the dithiane ring has been reported. The rearrangement provided 9-membered amino-functionalized sulfur-containing heterocycles (dithionine derivatives) in good yields under mild conditions. Propargylamines bearing 5-membered 1,3-dithiolane and 7-membered 1,3-dithiepane rings rearranged in a similar manner yielding 8- and 10-membered <i>S,S</i>-heterocycles, respectively. Chemistry ; Ring (chemistry) ; Sulfur ; Dithiolane ; Base (topology) ; Dithiane ; Combinatorial chemistry ; Stereochemistry ; Medicinal chemistry ; Organic chemistry Sulfur-Based Synthesis Techniques ; Click Chemistry and Applications ; Synthesis and Catalytic Reactions
Authors: Shekhar Gupta | Yuki Yamawaki | Safalmani Pradhan | Shyam S. Pandey | Tamaki Kato
Source: physica status solidi (a) (article, 2023-06-16)
Field: Chemistry — Spectroscopy

Design and Synthesis of Novel Squaraine Dye with Highly Enhanced Far‐Red Fluorescence and its Interaction with a Model Protein Novel amine‐functionalized symmetrical squaraine (SQ)‐dye and fluorescein isothiocyanate (FITC)–SQ–FITC dye conjugate are designed and successfully synthesized, followed by their structural and photophysical characterizations. Symmetrical SQ dye exhibits complete fluorescence quenching in polar solvents, which is explained by considering photoinduced electron transfer (PET) as a dominant quenching pathway. In contrast, FITC–SQ–FITC dye conjugate results in a decrease in an aggregation of both SQ and FITC units and about 47 times enhancement in the far‐red fluorescence appearing at 674 nm. This profound enhancement in the far‐red fluorescence is explained by the synergistic influence of suppression of aggregation‐induced quenching (ACQ) and PET. This newly designed FITC–SQ–FITC dye conjugate shows complete quenching of the far‐red fluorescence in phosphate buffer saline (PBS) owing to very strong dye aggregation, as confirmed by spectral absorption investigation. In PBS, it strongly interacts with bovine serum albumin (BSA) ( K a = 1.1 × 10 4 m −1 ) used as a model protein breaking the dye aggregation by BSA and increasing far‐red fluorescence associated with SQ as a function of increasing BSA concentration. A profound 117 times increase in fluorescence at 674 nm with 25 times of BSA concentration suggests that the designed FITC–SQ–FITC is an excellent far‐red probe for dye‐protein interaction. Fluorescence ; Photochemistry ; Quenching (fluorescence) ; Chemistry ; Fluorescein ; Fluorescein isothiocyanate ; Conjugate ; Bovine serum albumin ; Absorption (acoustics) ; Materials science ; Chromatography ; Optics Molecular Sensors and Ion Detection ; Photochemistry and Electron Transfer Studies ; Luminescence and Fluorescent Materials
Authors: Lukas W. Bingel | Zhenzi Yu | David S. Sholl | Krista S. Walton
Source: The Journal of Physical Chemistry C (article, 2023-10-12)
Field: Chemistry — Inorganic Chemistry

Does Mixed Linker-Induced Surface Heterogeneity Impact the Accuracy of IAST Predictions in UiO-66-NH<sub>2</sub>? To move toward more energy-efficient adsorption-based processes, there is a need for accurate multicomponent data under realistic conditions. While the Ideal Adsorbed Solution Theory (IAST) has been established as the preferred prediction method due to its simplicity, limitations and inaccuracies for less ideal adsorption systems have been reported. Here, we use amine-functionalized derivatives of the UiO-66 structure to change the extent of homogeneity of the internal surface toward the adsorption of the two probe molecules carbon dioxide and ethylene. Although it might seem plausible that more functional groups lead to more heterogeneity and, thus, less accurate predictions by IAST, we find a mixed-linker system with increased heterogeneity in terms of added adsorption sites where IAST predictions and experimental loadings agree exceptionally well. We show that incorporating uncertainty analysis into predictions with IAST is important for assessing the accuracy of these predictions. Energetic investigations combined with Grand Canonical Monte Carlo simulations reveal almost homogeneous carbon dioxide but heterogeneous ethylene adsorption in the mixed-linker material, resulting in local, almost pure phases of the individual components. Adsorption ; Homogeneous ; Homogeneity (statistics) ; Ethylene ; Molecule ; Amine gas treating ; Linker ; Monte Carlo method ; Chemistry ; Chemical physics ; Materials science ; Thermodynamics ; Physical chemistry ; Computer science ; Organic chemistry ; Physics ; Mathematics ; Statistics ; Catalysis Zeolite Catalysis and Synthesis ; Catalytic Processes in Materials Science ; Carbon Dioxide Capture Technologies
Authors: Austin Che | Carson Zellman | Diganta Sarkar | Simon Trudel-Lachance | Jayar Espejo | Vladimir K. Michaelis | Vance E. Williams | Chang‐Chun Ling
Source: Journal of Materials Chemistry C (article, 2023-01-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Functional group polarity-modulated formation of liquid crystals of amphiphilic cyclodextrins Polyesterified amphiphilic β-cyclodextrin derivatives bearing functionalized tetraethylene glycols showed excellent abilities to self-assemble into stable hexagonal columnar mesophases with 1D ion conducting channels. Amphiphile ; Materials science ; Polarity (international relations) ; Hexagonal crystal system ; Cyclodextrin ; Group (periodic table) ; Liquid crystal ; Crystallography ; Copolymer ; Polymer chemistry ; Organic chemistry ; Chemistry ; Composite material ; Polymer ; Biochemistry Liquid Crystal Research Advancements ; Advanced NMR Techniques and Applications ; Supramolecular Chemistry and Complexes