jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Junyou Wang | Lei Liu | Ilja K. Voets | Martien A. Cohen Stuart | Aldrik H. Velders
Source: Soft Matter (article, 2020-01-01)
Field: Materials Science — Polymers and Plastics

Dendrimicelles with pH-controlled aggregation number of core-dendrimers and stability We present a simple way to build up well-controlled coacervate-core dendrimicelles by assembly of anionic PAMAM dendrimers with a cationic-neutral diblock copolymer. Dendrimer ; Core (optical fiber) ; Stability (learning theory) ; Chemistry ; Nanotechnology ; Materials science ; Computer science ; Polymer chemistry ; Composite material Dendrimers and Hyperbranched Polymers ; Polymer Surface Interaction Studies ; RNA Interference and Gene Delivery
Authors: Nabil Bensabeh | Ana Jiménez-Alesanco | Ilme Liblikas | Juan C. Ronda | Virgínia Cádiz | Marina Galià | Lauri Vares | Olga Abián | Gerard Lligadas
Source: Molecules (article, 2020-12-05)
Field: Materials Science — Biomaterials

Biosourced All-Acrylic ABA Block Copolymers with Lactic Acid-Based Soft Phase Lactic acid is one of the key biobased chemical building blocks, given its readily availability from sugars through fermentation and facile conversion into a range of important chemical intermediates and polymers. Herein, well-defined rubbery polymers derived from butyl lactate solvent were successfully prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization of the corresponding monomeric acrylic derivative. Good control over molecular weight and molecular weight distribution was achieved in bulk using either monofunctional or bifunctional trithiocarbonate-type chain transfer agents. Subsequently, poly(butyl lactate acrylate), with a relative low <i>T</i><sub>g</sub> (-20 °C), good thermal stability (5% wt. loss at 340 °C) and low toxicity was evaluated as a sustainable middle block in all-acrylic ABA copolymers using isosorbide and vanillin-derived glassy polyacrylates as representative end blocks. Thermal, morphological and mechanical properties of copolymers containing hard segment contents of <20 wt% were evaluated to demonstrate the suitability of rubbery poly(alkyl lactate) building blocks for developing functional sustainable materials. Noteworthy, 180° peel adhesion measurements showed that the synthesized biosourced all-acrylic ABA copolymers possess competitive performance when compared with commercial pressure-sensitive tapes. Copolymer ; Acrylic acid ; Polymer chemistry ; Chain transfer ; Polymer ; Polymerization ; Thermal stability ; Lactic acid ; Materials science ; Chemical engineering ; Chemistry ; Organic chemistry ; Radical polymerization biodegradable polymer synthesis and properties ; Advanced Polymer Synthesis and Characterization ; Synthetic Organic Chemistry Methods
Authors: Camilla Facciotti | Vittorio Saggiomo | Anton Bunschoten | Jan Bart ten Hove | Marcus T. M. Rood | Fijs W. B. van Leeuwen | Aldrik H. Velders
Source: ChemSystemsChem (article, 2020-01-27)
Field: Materials Science — Surfaces, Coatings and Films

Assembly, Disassembly and Reassembly of Complex Coacervate Core Micelles with Redox‐Responsive Supramolecular Cross‐Linkers Abstract Polymer‐based micellar assemblies are gaining increasing attention in the smart materials field, yet the design of micelles that show redox‐responsive disassembly and, e. g., cargo release is still a challenge. To form redox‐responsive micelles, we developed cyclodextrin‐based coacervate core micelles that form under interplay of four orthogonal interactions: multivalent electrostatic coacervation, metal‐to‐ligand coordination chemistry, supramolecular host‐guest interactions, and a reversible covalent disulfide metal‐complex crosslinker. The cleavage of this crosslinker by dithiotreithol results in the breaking of oligomeric europium(III) structures in the core and results in the disassembly of the 70 nm size micelles. Over hours, due to the oxidation of thiolates to disulfides, monomeric units can re‐crosslink into oligomeric core‐units, favoring micellar reassembly. The time required to reassemble can be controlled by varying the reducing agent concentration or the ratio between redox‐responsive and non‐redox‐responsive crosslinkers. Controlled Methyl Red encapsulation and release indicate the potential of these micelles, for, e. g., controlled drug uptake and delivery. Coacervate ; Micelle ; Redox ; Chemistry ; Supramolecular chemistry ; Combinatorial chemistry ; Monomer ; Supramolecular polymers ; Polymer ; Polymer chemistry ; Organic chemistry ; Crystal structure ; Chromatography ; Aqueous solution Polymer Surface Interaction Studies ; Nanoparticle-Based Drug Delivery ; Advanced Polymer Synthesis and Characterization
Authors: Rüdiger M. Exner | Fernando Cortezon‐Tamarit | Sofia I. Pascu
Source: Angewandte Chemie (article, 2020-09-22)
Field: Chemistry — Organic Chemistry

Explorations into the Effect of <i>meso</i>‐Substituents in Tricarbocyanine Dyes: A Path to Diverse Biomolecular Probes and Materials Abstract Polymethine cyanine dyes have been widely recognized as promising chemical tools for a range of life science and biomedical applications, such as fluorescent staining of DNA and proteins in gel electrophoresis, fluorescence guided surgery, or as ratiometric probes for probing biochemical pathways. The photophysical properties of such dyes can be tuned through the synthetic modification of the conjugated backbone, for example, by altering aromatic cores or by varying the length of the conjugated polymethine chain. Alternative routes to shaping the absorption, emission, and photostability of dyes of this family are centered around the chemical modifications on the polymethine chain. This Minireview aims to discuss strategies for the introduction of substituents in the meso‐position, their effect on the photophysical properties of these dyes and some structure–activity correlations which could help overcome common limitations in the state of the art in the synthesis. Cyanine ; Conjugated system ; Chemistry ; Fluorescence ; Combinatorial chemistry ; Absorption (acoustics) ; Nanotechnology ; Photochemistry ; Polymer ; Organic chemistry ; Materials science Click Chemistry and Applications ; Nanoplatforms for cancer theranostics ; Photodynamic Therapy Research Studies
Authors: Jie Jian | Jordi Poater | Roel Hammink | Paul Tinnemans | Christine J. McKenzie | F. Matthias Bickelhaupt | Jasmin Mecinović
Source: ChemPhysChem (article, 2020-04-06)
Field: Chemistry — Organic Chemistry

Through‐Space Polar‐π Interactions in 2,6‐Diarylthiophenols Molecular recognition between polar groups and aromatic molecules is fundamentally important to rational drug design. Although it has been well established that many polar functionalities interact with electron-rich aromatic residues through energetically favorable polar-π interactions, there is a limited understanding of the association between thiols and aromatic systems. Herein we report physical-organic chemistry studies on 2,6-diarylthiophenols that possess the central thiophenol ring and two flanking aromatic rings with tunable electronic properties caused by substituents at distant para position. Hammett analysis revealed that pK<sub>a</sub> values and proton affinities correlate well with Hammett sigma values of substituents. Additional energy decomposition analysis supported the conclusion that both through-space SH-π interactions and S<sup>-</sup> -π interactions contribute to intramolecular stabilization of 2,6-diarylthiophenols. Polar ; Space (punctuation) ; Chemical physics ; Chemistry ; Materials science ; Nanotechnology ; Computational chemistry ; Physics ; Computer science ; Quantum mechanics Organic Chemistry Cycloaddition Reactions ; Crystallography and molecular interactions ; Photochromic and Fluorescence Chemistry
Authors: Tyler Del Rose | Arjun K. Pathak | Yaroslav Mudryk | V. K. Pecharsky
Source: Journal of Materials Chemistry C (article, 2020-11-27)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Distinctive exchange bias and unusual memory effects in magnetically compensated Pr<sub>0.75</sub>Gd<sub>0.25</sub>ScGe Inter-lanthanide interactions in a distinctly layered lattice lead to magnetic compensation, exchange bias, and magnetic memory effects. Exchange bias ; Materials science ; Lanthanide ; Lattice (music) ; Condensed matter physics ; Physics ; Magnetization ; Ion ; Magnetic field ; Magnetic anisotropy Magnetic and transport properties of perovskites and related materials ; Rare-earth and actinide compounds ; Advanced Condensed Matter Physics
Authors: Yaakov Mandelbaum | Raz Mottes | Zeev Zalevsky | David Zitoun | Avi Karsenty
Source: Sensors (article, 2020-09-08)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Design of Surface Enhanced Raman Scattering (SERS) Nanosensor Array An advanced Surface-Enhanced Raman Scattering (SERS) Nanosensor Array, dedicated to serve in the future as a pH imager for the real-time detection of chemical reaction, is presented. The full flow of elementary steps-architecture, design, simulations, fabrication, and preliminary experimental results of structural characterization (Focused Ion Beam (FIB), TEM and SEM)-show an advanced SERS pixel array that is capable of providing spatially resolved measurements of chemical pH in a fluid target that became more than desirable in this period. Ultimately, the goal will be to provide real-time monitoring of a chemical reaction. The pixels consist of a nanostructured substrate composed of an array of projections or cavities. The shape of the nanostructures and the thickness of the metallic (Ag or Au) layer can be tuned to give maximal enhancement at the desired wavelength. The number and arrangement of nanostructures is optimized to obtain maximal responsivity. Raman scattering ; Nanosensor ; Responsivity ; Materials science ; Nanostructure ; Fabrication ; Substrate (aquarium) ; Nanotechnology ; Characterization (materials science) ; Scattering ; Optoelectronics ; Raman spectroscopy ; Optics ; Physics Gold and Silver Nanoparticles Synthesis and Applications ; Advanced biosensing and bioanalysis techniques ; Biosensors and Analytical Detection
Authors: Yan B. Vogel | Á. Molina | Joaquı́n González | Simone Ciampi
Source: Electrochimica Acta (article, 2020-07-30)
Field: Chemistry — Electrochemistry

Microelectrode arrays with active-area geometries defined by spatial light modulation Microelectrode ; Electrode ; Silicon ; Diffusion ; Materials science ; Multielectrode array ; Semiconductor ; Modulation (music) ; Electrochemistry ; Current (fluid) ; Optoelectronics ; Chemistry ; Nanotechnology ; Physics ; Acoustics Electrochemical Analysis and Applications ; Analytical Chemistry and Sensors ; Neuroscience and Neural Engineering
Authors: Dario Lunni | Goffredo Giordano | Francesca Pignatelli | Carlo Filippeschi | Stefano Linari | Edoardo Sinibaldi | Barbara Mazzolai
Source: Scientific Reports (article, 2020-10-01)
Field: Materials Science — Biomaterials

Light-assisted electrospinning monitoring for soft polymeric nanofibers A real-time tool to monitor the electrospinning process is fundamental to improve the reproducibility and quality of the resulting nanofibers. Hereby, a novel optical system integrated through coaxial needle is proposed as monitoring tool for electrospinning process. An optical fiber (OF) is inserted in the inner needle, while the external needle is used to feed the polymeric solution (PEO/water) drawn by the process. The light exiting the OF passes through the solution drop at the needle tip and gets coupled to the electrospun fiber (EF) while travelling towards the nanofibers collector. Numerical and analytical models were developed to assess the feasibility and robustness of the light coupling. Experimental tests demonstrated the influence of the process parameters on the EF waveguide properties, in terms of waveguide length (L), and on the nanofibers diameter distribution, in terms of mean [Formula: see text] and normalized standard deviation [Formula: see text]. Data analysis reveals good correlation between L and [Formula: see text] (respectively maximum correlation coefficients of [Formula: see text] = 0.88 and [Formula: see text] = 0.84), demonstrating the potential for effectively using the proposed light-assisted technology as real-time visual feedback on the process. The developed system can provide an interesting option for monitoring industrial electrospinning systems using multi- or moving needles with impact in the scaling-up of innovative nanofibers for soft systems. Electrospinning ; Nanofiber ; Optical fiber ; Materials science ; Coaxial ; Robustness (evolution) ; Reproducibility ; Scaling ; Process (computing) ; Standard deviation ; Computer science ; Nanotechnology ; Biomedical engineering ; Composite material ; Polymer ; Mathematics ; Telecommunications ; Statistics ; Geometry ; Chemistry Electrospun Nanofibers in Biomedical Applications ; Advanced Sensor and Energy Harvesting Materials ; Conducting polymers and applications
Authors: Marjolein E. Haagsman | Margot Koster | Johannes Boonstra | Karin Scager
Source: Journal of Science Education and Technology (article, 2020-12-18)
Field: Chemistry — Physical and Theoretical Chemistry

Be Prepared! How Pre-lab Modules Affect Students’ Understanding of Gene Mapping Abstract Lab activities are characteristic of life science education. In the current study, we investigate whether pre-lab modules can improve students’ understanding of the theories and experimental procedures associated with lab activities. Such effects were studied in context of an expository lab on gene mapping in biology undergraduate education. An experimental group of 126 students had access to an online pre-lab module to prepare for the lab activity; a control group of 90 students did not have access to this pre-lab module. The data revealed that students who studied the pre-lab module had a better understanding of the gene mapping theory, at the onset of the class, when compared with the control group. Additionally, these students appeared to ask fewer questions on what needed to be done in the lab, suggesting more awareness of the experimental procedure. Further, students who studied the online pre-lab module showed greater understanding of the theory in their lab reports. These findings suggest that students’ understanding of background theory and its relation to practice can readily be improved by enriching existing expository labs with pre-lab modules that contain information and questions on the complex conceptual information relevant to the lab experiment. Context (archaeology) ; Mathematics education ; Science education ; Class (philosophy) ; Educational technology ; Affect (linguistics) ; Computer science ; Psychology ; Biology ; Artificial intelligence Various Chemistry Research Topics ; Science Education and Pedagogy ; Genetics, Bioinformatics, and Biomedical Research
Authors: Mohammad Nur‐E‐Alam | Md Momtazur Rahman | Mohammad Khairul Basher | Mikhail Vasiliev | Kamal Alameh
Source: Preprints.org (preprint, 2020-02-18)
Field: Materials Science — Materials Chemistry

Optical and Chromaticity Properties of Metal-Dielectric Composite-Based Multilayer Thin-Film Structures Prepared by RF Magnetron Sputtering Over the last decades, the coated glass products, and especially the low-emissivity coatings have become a common building material used in modern architectural projects. More recently, these material systems became common in specialized glazing systems featuring solar energy harvesting. Apart from achieving the stability of optical parameters in multilayer coatings, it is also important to have improved control over the design of visual color properties of the coated glass. We prepare metal-dielectric composite (MDC) based multilayer thin-film structures using the RF-magnetron sputtering deposition and report on their optical and chromaticity properties in comparison with these obtained using pure metal-based Dielectric/Metal/Dielectric (DMD) trilayer structures of similar compositions. Experimentally achieved Hunter L, a, b values of MDC-based multilayer building blocks of coatings provide a new outlook on the engineering of future-generation optical coatings with better color consistency and developing approaches to broaden the range of achievable color coordinates and better environmental stability. Chromaticity ; Materials science ; Glazing ; Dielectric ; Sputter deposition ; Thin film ; Optoelectronics ; Composite number ; Optical coating ; Composite material ; Optics ; Deposition (geology) ; Sputtering ; Engineering physics ; Nanotechnology Silicon Nanostructures and Photoluminescence ; Photonic Crystals and Applications ; Transition Metal Oxide Nanomaterials
Authors: Kai Du | Lei Guo | Jin Peng | Xing Chen | Zheng-Nan Zhou | Yang Zhang | Ting Zheng | Yan-Ping Liang | Jun-Peng Lu | Zhen-Hua Ni | Shan-Shan Wang | Gustaaf Van Tendeloo | Ze Zhang | Shuai Dong | He Tian
Source: npj Quantum Materials (article, 2020-07-23)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Direct visualization of irreducible ferrielectricity in crystals Abstract In solids, charge polarity can one-to-one correspond to spin polarity phenomenologically, e.g., ferroelectricity/ferromagnetism, antiferroelectricity/antiferromagnetism, and even dipole-vortex/magnetic-vortex, but ferrielectricity/ferrimagnetism kept telling a disparate story in microscopic level. Since the definition of a charge dipole involves more than one ion, there may be multiple choices for a dipole unit, which makes most ferrielectric orders equivalent to ferroelectric ones, i.e., this ferrielectricity is not necessary to be a real independent branch of polarity. In this work, by using the spherical aberration-corrected scanning transmission electron microscope, we visualize a nontrivial ferrielectric structural evolution in BaFe 2 Se 3 , in which the development of two polar sub-lattices is out-of-sync, for which we term it as irreducible ferrielectricity. Such irreducible ferrielectricity leads to a non-monotonic behavior for the temperature-dependent polarization, and even a compensation point in the ordered state. Our finding unambiguously distinguishes ferrielectrics from ferroelectrics in solids. Polarity (international relations) ; Polar ; Ferroelectricity ; Dipole ; Charge (physics) ; Point (geometry) ; Compensation (psychology) ; Chemical polarity Iron-based superconductors research ; Organic and Molecular Conductors Research ; Chemical and Physical Properties of Materials
Authors: Ritu Gupta | A. Maisuradze | N. D. Zhigadlo | H. Luetkens | A. Amato | R. Khasanov
Source: Frontiers in Physics (article, 2020-01-30)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Self-Consistent Two-Gap Approach in Studying Multi-Band Superconductivity of NdFeAsO0.65F0.35 High quality single crystals of NdFeAsO$_{0.65}$F$_{0.35}$ (the superconducting transition temperature $T_{\rm c}\simeq 30.6$~K) were studied in zero-field (ZF) and transverse-field (TF) muon-spin rotation/relaxation ($\mu$SR) experiments. An upturn in muon-spin depolarization rate at $T\lesssim 3$~K was observed in ZF-$\mu$SR measurements and it was associated with the onset of ordering of Nd electronic moments. Measurements of the magnetic field penetration depth ($\lambda$) were performed in the TF geometry. By applying the external magnetic field $B_{\rm ex}$ parallel to the crystallographic $c$-axis ($B_{\rm ex}\| c$) and parallel to the $ab$-plane ($B_{\rm ex}\| ab$), the temperature dependencies of the in-plane component ($\lambda_{ab}^{-2}$) and the combination of the in-plane and the out of plane components ($\lambda_{ab,c}^{-2}$) of the superfluid density were determined, respectively. The out-of-plane superfluid density component ($\lambda_{c}^{-2}$) was further obtained by combining the results of $B_{\rm ex} \| c$ and $B_{\rm ex} \| {ab}$ set of experiments. The temperature dependencies of $\lambda_{ab}^{-2}$, $\lambda_{ab,c}^{-2}$, and $\lambda_{c}^{-2}$ were analyzed within the framework of a self-consistent two-gap model despite of using the traditional $\alpha$-model. Interband coupling was taken into account, instead of assuming it to be zero as it stated in the $\alpha$-model. A relatively small value of the interband coupling constant $\Lambda_{12} \simeq 0.01$ was obtained, thus indicating that the energy bands in NdFeAsO$_{0.65}$F$_{0.35}$ are only weakly coupled. In spite of their small magnitude, the coupling between the bands leads to the single value of the superconducting transition temperature $T_{\rm c}$. The penetration depth anisotropy $\gamma_{\lambda}=\lambda_c/\lambda_{ab}$ was found to increase upon cooling, consistent with most of Fe-based superconductors, and their behavior is attributed to the multi-band nature of superconductivity in NdFeAsO$_{0.65}$F$_{0.35}$. Physics ; Lambda ; Superconductivity ; Condensed matter physics ; Muon spin spectroscopy ; Superfluidity ; Penetration depth ; Coupling (piping) ; Quantum mechanics ; Materials science Iron-based superconductors research ; Physics of Superconductivity and Magnetism ; Superconductivity in MgB2 and Alloys
Authors: Daniil Bash | Yongqiang Cai | Vijila Chellappan | Swee Liang Wong | Xu Yang | Pawan Kumar | Jin Da Tan | Anas Abutaha | Jayce Jian Wei Cheng | Yee‐Fun Lim | Siyu Tian | Zekun Ren | Wai Kuan Wong | Flore Mekki‐Berrada | Jatin Kumar | Saif A. Khan | Qianxiao Li | Tonio Buonassisi | Kedar Hippalgaonkar
Source: ChemRxiv (preprint, 2020-11-23)
Field: Materials Science — Materials Chemistry

Machine Learning and High-Throughput Robust Design of P3HT-CNT Composite Thin Films for High Electrical Conductivity Combining high-throughput experiments with machine learning allows quick optimization of parameter spaces towards achieving target properties. In this study, we demonstrate that machine learning, combined with multi-labeled datasets, can additionally be used for scientific understanding and hypothesis testing. We introduce an automated flow system with high-throughput drop-casting for thin film preparation, followed by fast characterization of optical and electrical properties, with the capability to complete one cycle of learning of fully labeled ~160 samples in a single day. We combine regio-regular poly-3-hexylthiophene with various carbon nanotubes to achieve electrical conductivities as high as 1200 S/cm. Interestingly, a non-intuitive local optimum emerges when 10% of double-walled carbon nanotubes are added with long single wall carbon nanotubes, where the conductivity is seen to be as high as 700 S/cm, which we subsequently explain with high fidelity optical characterization. Employing dataset resampling strategies and graph-based regressions allows us to account for experimental cost and uncertainty estimation of correlated multi-outputs, and supports the proving of the hypothesis linking charge delocalization to electrical conductivity. We therefore present a robust machine-learning driven high-throughput experimental scheme that can be applied to optimize and understand properties of composites, or hybrid organic-inorganic materials. Carbon nanotube ; Materials science ; Conductivity ; Throughput ; Computer science ; High fidelity ; Characterization (materials science) ; Resampling ; Composite number ; Electrical resistivity and conductivity ; Nanotechnology ; Process engineering ; Artificial intelligence ; Algorithm ; Composite material ; Physics Machine Learning in Materials Science ; Advanced Memory and Neural Computing ; Organic Electronics and Photovoltaics