jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Yomen Atassi | Rédouane Borsali
Source:  (preprint, 2021-10-18)
Field: Materials Science — Biomaterials

New Insights on the Self-Assembly of Bio-sourced Block Copolymer MH-b-PS in Aqueous Solutions: Nanocorals, Cubosomes &amp;amp; Nanocubes Polymer self-assembly in solution still constitutes a simple methodology for the preparation of elegant yet sophisticated nanomaterials. This work aims at presenting how the fine tuning of the experimental parameters of the nanoprecipitation process can lead to a variety of novel morphologies ranging from nanocorals through cubosomes to nanocubes. A carbohydrate dibloc copolymer with a simple and linear structure MH1.2k-b-PS2.3 has been used as a model to illustrate the formation of these new self-assemblies. This is the first time that nanocube morphology has been generated using this type of bio-sourced co-polymer in aqueous solution and at room temperature. Copolymer ; Aqueous solution ; Polymer ; Nanomaterials ; Nanotechnology ; Self-assembly ; Materials science ; Chemical engineering ; Chemistry ; Polymer chemistry ; Organic chemistry Supramolecular Self-Assembly in Materials ; Block Copolymer Self-Assembly ; Mesoporous Materials and Catalysis
Authors: Augustine George | Mohan Indhu | Sundarapandian Ashokraj | Ganesh Shanmugam | Ganesan Ponesakki | Numbi Ramudu Kamini | Niraikulam Ayyadurai
Source: Research Square (preprint, 2021-05-07)
Field: Chemistry — Organic Chemistry

Genetically Encoded Dihydroxyphenylalanine Coupled with Tyrosinase for Strain Promoted Labeling Dihydroxyphenylalanine ; Tyrosinase ; Strain (injury) ; Chemistry ; Genetically engineered ; Biochemistry ; Biology ; Gene ; Neuroscience ; Enzyme ; Anatomy ; Dopamine Click Chemistry and Applications ; Chemical Synthesis and Analysis ; Monoclonal and Polyclonal Antibodies Research
Authors: Brandon J. Bayard
Source: ECS Meeting Abstracts (article, 2021-05-30)
Field: Materials Science — Materials Chemistry

Design, Synthesis and Characterization of Molecular Components for Light Induced Molecular Machines Molecular machines are systems of molecules that convert chemical energy into mechanical forces. They have a range of potential applications such as transportation of chemicals or use as an arity signal for computation. In literature, most molecular machines are activated through some form of chemical signal. This has a range of drawbacks from limiting the range of environments the machine can function in to the buildup of byproducts of the chemical reaction. The solution to these limitations was found in the synthesis and characterization of various light induced molecular machines. Like the name implies, this subset of molecular machines uses light as the signal that activates the mechanism. The model of molecular machine being worked on in this research is a porphyrin-based molecular shuttle shown in scheme 1. Upon photoexcitation of the porphyrin acceptor, represented by the symbol A, an electron transfer from naphthyl group to the porphyrin occurs. Following this photoinduced electron transfer, a radical pair is formed between the porphyrin and naphthyl group. The newly generated naphthyl cation is expected to drive the macrocycle situated around the naphthalene towards the aryl group due to the more favourable interactions. Upon relaxation of the radical pair through back electron transfer, the macrocycle is expected to return to the naphthalene group due to the regeneration of the electron density on the naphthyl group. In this context, novel molecular machine components have been synthesized and characterized using various spectroscopic and electrochemical techniques. The goal of which, is to fine tune the chemical, physical and synthetical properties such that they are suitable for future use in a complete molecular machine as described in scheme 1. Figure 1 Porphyrin ; Photoexcitation ; Context (archaeology) ; Molecular machine ; Electron transfer ; Chemistry ; Chemical physics ; Molecule ; Materials science ; Photochemistry ; Computational chemistry ; Nanotechnology ; Atomic physics ; Organic chemistry ; Physics Porphyrin and Phthalocyanine Chemistry ; Molecular Junctions and Nanostructures ; Various Chemistry Research Topics
Authors: Carlos Lodeiro | Silvia Nuti | Carlos Fernández‐Lodeiro | Javier Fernández‐Lodeiro | Adrián Fernández‐Lodeiro | Jorge Pérez‐Juste | Isabel Pastoriza Santos | Alec P. LaGrow | Olivier Schraidt | José Luís Capelo
Source: ChemRxiv (preprint, 2021-08-23)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Polyallylamine assisted synthesis of 3D branched AuNPs with plasmon tunability in the vis-NIR region modification. This paper describes the synthesis of highly branched gold nanoparticles through a facile seeded growth approach using poly(allylamine hydrochloride) (PAH) as shape inducing agent. The obtained branched Au NPs present highly tunable optical properties in the Vis-NIR region from ca. 560 nm to 1260 nm. We controlled the morphology, and therefore the optical response, of the NPs by either changing the gold salt to seed ratio or fine-tuning the solution pH. We proposed that the formation of size-dependent PAH-AuCl4- aggregates as demonstrated by dynamic light scattering measurements, together with pH-dependent gold salt speciation, might be responsible for the branched morphology. Advanced electron microscopy techniques demonstrated the polycrystalline nature of the NPs and facilitated a better understanding of branched morphology. Additionally, the refractive index sensitivity estimated by the inflexion point of the Localized Surface Plasmon Resonance (LSPR) band can be controlled by tuning the nanoparticle branching. Furthermore, the versatility of the PAH chemistry allowed the easy functionalization of the synthesized NPs. Surface plasmon resonance ; Surface modification ; Colloidal gold ; Materials science ; Nanoparticle ; Branching (polymer chemistry) ; Dynamic light scattering ; Plasmon ; Allylamine ; Morphology (biology) ; Nanotechnology ; Chemical engineering ; Crystallite ; Optoelectronics ; Polyelectrolyte ; Polymer Gold and Silver Nanoparticles Synthesis and Applications ; Laser-Ablation Synthesis of Nanoparticles ; Graphene and Nanomaterials Applications
Authors: Augustine George | Mohan Indhu | Sundarapandian Ashokraj | Ganesh Shanmugam | Ganesan Ponesakki | Numbi Ramudu Kamini | Niraikulam Ayyadurai
Source: Research Square (preprint, 2021-03-19)
Field: Chemistry — Organic Chemistry

Genetically Encoded Dihydroxyphenylalanine Coupled with Tyrosinase for Strain Promoted Labelling Abstract Protein modifications through the genetic code engineering method have a remarkable impact on macromolecule engineering, protein translocation, protein-protein interaction, and cell biology. Here, the newly developed molecular biology approach expanding the genetic code was used for fine tuning of protein for biological availability. For that non-canonical amino acid dihydroxyphenylalanine was genetically incorporated at the defined site in the protein. Further, the congener protein was enzymatically controlled for direct conversion of quinone for strain promoted click chemistry reaction. It yields a single product with defined stereochemistry and temporally controlled conjugation with BCN. The feasibility was explored for selective cell imaging and programmed cell death in HeLa cells. Tyrosinase ; Labelling ; Strain (injury) ; Dihydroxyphenylalanine ; Chemistry ; Genetically engineered ; Biochemistry ; Biology ; Gene ; Enzyme ; Neuroscience ; Dopamine ; Anatomy Click Chemistry and Applications ; Monoclonal and Polyclonal Antibodies Research ; Chemical Synthesis and Analysis
Authors: John M. Kapitan
Source: Insecta mundi (article, 2021-01-01)
Field: Materials Science — Biomaterials

Surface Functionalization of Elastomers for Tunable Crystal Growth and Smart Adhesives Silicone rubbers have seen extensive work on modulation of their surface environments for use in microfluidics, cell adhesion, and sensing. Most surface procedures utilize a common initial step of oxidation of the surface to increase the number of active surface functional groups. Following oxidation more permanent functionalities can be imparted on the surface using silanization, grafting polymer brushes, or creating ionic bonds to the surface. Of these three, silanization proves to be the most pervasive due to the range of procedures available and how easy the procedures prove to be. However, the mechanism by which silanization is performed heavily involves reactivity with alcohol groups making the procedure unavailable to functional groups containing alcohols and functional groups that share similar structural features. Expanding the scope of functional groups available through silanization can be achieved by attaching groups to the surface that can be easily replaced or transformed. Increasing the scope of available surface functional groups was achieved by using the copper catalyzed azide-alkyne click reaction. Controlling the areas that reactivity occurs at, by using patterning techniques, allow for the generation of distinct regimes of surface chemistry. This can allow for wholly new surface functions such as the ordering of large arrays of liquid droplets, directional control of the movement of droplets across the surface, and control over the adhesive forces the surface experiences. Combining chemical patterning with physical patterning, selective removal of contact areas, allowed for fine tuning of the adhesive properties and produced a favorable delamination axis. The work outlined here is applicable to a broad range of fields including, biomineralization, biomaterial engineering, and adhesive design. Advisor: Stephen A. Morin Surface modification ; Elastomer ; Adhesive ; Materials science ; Surface (topology) ; Composite material ; Polymer science ; Mechanical engineering ; Engineering ; Mathematics ; Geometry biodegradable polymer synthesis and properties ; Advanced Sensor and Energy Harvesting Materials ; Advanced Polymer Synthesis and Characterization
Authors: Светлана Иванова | Eva Köster | Julian J. Holstein | Niklas Keller | Guido H. Clever | Thomas Bein | Florian Beuerle
Source: ChemRxiv (preprint, 2021-03-02)
Field: Materials Science — Materials Chemistry

Isoreticular Crystallization of Highly Porous Cubic Covalent Organic Cage Compounds Modular frameworks featuring well-defined pore structures in microscale domains establish tailor-made porous materials. For open molecular solids however, maintaining long-range order after desolvation is inherently challenging, since packing is usually governed by only a few supramolecular interactions. Here we report on two series of nanocubes obtained by co-condensation of two different hexahydroxy tribenzotriquinacenes (TBTQs) and benzene-1,4-diboronic acids (BDBAs) with varying linear alkyl chains in 2,5-position. nButyl groups at the apical position of the TBTQ vertices yielded soluble model compounds, which were analyzed by mass spectrometry and NMR spectroscopy. In contrast, methyl-substituted cages spontaneously crystallized as isostructural and highly porous solids with BET surface areas and pore volumes of up to 3426 m2 g−1 and 1.82 cm3 g−1. Single crystal X-ray diffraction and sorption measurements revealed an intricate cubic arrangement of alternating micro- and mesopores in the range of 0.97–2.2 nm that are fine-tuned by the alkyl substituents at the BDBA linker. Isostructural ; Crystallography ; Mesoporous material ; Alkyl ; Crystallization ; Supramolecular chemistry ; Chemistry ; Porosity ; Sorption ; Chemical engineering ; Materials science ; Crystal structure ; Organic chemistry ; Adsorption Covalent Organic Framework Applications ; Supramolecular Chemistry and Complexes ; Metal-Organic Frameworks: Synthesis and Applications
Authors: Yomen Atassi | Rédouane Borsali
Source: ChemRxiv (preprint, 2021-10-17)
Field: Materials Science — Biomaterials

New Insights on the Self-Assembly of Bio-sourced Block Copolymer MH-b-PS in Aqueous Solutions: Nanocorals, Cubosomes &amp; Nanocubes Polymer self-assembly in solution still constitutes a simple methodology for the preparation of elegant yet sophisticated nanomaterials. This work aims at presenting how the fine tuning of the experimental parameters of the nanoprecipitation process can lead to a variety of novel morphologies ranging from nanocorals through cubosomes to nanocubes. A carbohydrate dibloc copolymer with a simple and linear structure MH1.2k-b-PS2.3 has been used as a model to illustrate the formation of these new self-assemblies. This is the first time that nanocube morphology has been generated using this type of bio-sourced co-polymer in aqueous solution and at room temperature. Copolymer ; Aqueous solution ; Nanomaterials ; Polymer ; Nanotechnology ; Materials science ; Self-assembly ; Chemical engineering ; Chemistry ; Organic chemistry Supramolecular Self-Assembly in Materials ; Block Copolymer Self-Assembly ; Mesoporous Materials and Catalysis
Authors: Emma K. Holland
Source: UKnowledge (University of Kentucky) (article, 2021-08-11)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Synthesis, Crystal Engineering, and Material Properties of Small-Molecule Organic Semiconductors Small-molecule organic materials are of increasing interest for electronic and photonic devices due to their solution processability and tunability, allowing devices to be fabricated at low temperature on flexible substrates and offering utility in specialized applications. This tunability is the result of functionalization through careful synthetic strategy to influence both material properties and solid-state arrangement, both crucial variables in device applications. Functionalization of a core molecule with various substituents allows the fine-tuning of optical and electronic properties, and functionalization with solubilizing groups allows some degree of control over the solid- state order, or crystal packing. These combinations of core chromophores with varying substituents are systematically evaluated to develop structure-function relationships that can be applied to numerous applications. This is the basis of Chapter 2, which focuses on identifying trends between physical structure and resulting optical and electronic properties in heteroacenes. In Chapter 3, the chromophores of Chapter 2 are further functionalized with substituents that allow them to work in tandem with inorganic materials for a hybrid singlet fission-triplet harvesting photovoltaic system. Chapter 4 further explores these key chromophores with still other substituents, here for isolated triplet pair generation and eventual quantum computing applications. Finally, Chapter 5 explores a relatively understudied class of formally antiaromatic compounds, the octadehydro[12]annulenes, demonstrating a unique effort at crystal engineering these molecules using similar strategies as in Chapter 2. A comprehensive overview of the physical, optical, and electronic properties is offered, providing a robust basis for future work. Organic semiconductor ; Semiconductor ; Crystal (programming language) ; Materials science ; Crystal engineering ; Molecule ; Crystal structure ; Crystallography ; Nanotechnology ; Optoelectronics ; Chemistry ; Computer science ; Organic chemistry ; Supramolecular chemistry Organic and Molecular Conductors Research
Authors: Anton Chernukha | Анастасия Александровна Зверева | G. M. Zirnik | Карина Эльвировна Мустафина | D. Pashnin | О. Dyukova | E. Malev | A.I. Vepreva | Валерия Вячеславовна Крошнина | N. S. Nekorysnova | В.Е. Живулин | Татьяна Владимировна Мосунова | Д.А. Винник
Source: Bulletin of the South Ural State University series Chemistry (article, 2021-01-01)
Field: Materials Science — Materials Chemistry

Application of Self-Combustion Method for Synthesis of Aluminum-Substituted Barium Hexaferrite Oxide materials have traditionally attracted the attention of researchers around the world. This is due to their wide range of applications: electrical engineering, electronics, special coatings, chemical technologies, etc. Doping of oxide materials with various elements such as Al, Bi, Zn, Co, Sn, Ti, B, Sb and others is widespread in order to fine-tune their physicochemical properties. In particular, doping of barium hexaferrite with aluminum is of particular interest, since this allows one to change such important parameters as saturation magnetization (σS), coercive force (HC), squareness coefficient of the hysteresis loop (K), as well as to influence the anisotropy field and microwave properties of the material. Since the preparation of BaAlxFe12-xO19 by the classical ceramic method requires thorough grinding of the starting materials, preliminary sintering, high temperature (above 1300 °C) and duration of the synthesis, it was decided to test an alternative method for obtaining aluminum-substituted barium hexaferrite. As such, we have chosen the self-combustion method. During the synthesis a solution of nitrates of the corresponding metals with citric acid was prepared. After neutralization and evaporation of the solution, the resulting mass was heated in a muffle furnace to carry out the spontaneous combustion process and remove residual carbon. The final sintering of samples with the composition BaAlxFe12-xO19 (for x = 0, 1, 2, and 3) was carried out in a muffle furnace with a precision temperature controller at 1100 °C for 4 hours. The obtained samples were studied by the powder diffractometry method, scanning electron microscopy, and X-ray spectral microanalysis. It has been established that the self-ignition method makes it possible to obtain homogeneous samples of barium hexaferrite substituted with aluminum at a lower temperature compared to the classical ceramic method. The parameters of the structure of the obtained samples were also determined. The tested method not only makes it possible to obtain aluminum-substituted barium hexaferrite at lower temperatures, but also makes it possible to dope ferrites with highly volatile elements. Muffle furnace ; Materials science ; Coercivity ; Sintering ; Ceramic ; Combustion ; Evaporation ; Chemical engineering ; Calcination ; Metallurgy ; Analytical Chemistry (journal) ; Chemistry ; Organic chemistry Magnetic Properties and Synthesis of Ferrites ; Electromagnetic wave absorption materials ; Pigment Synthesis and Properties
Authors: Clara R. Correia | Isabel M. Bjørge | Sara Nadine | João F. Mano
Source: Zenodo (CERN European Organization for Nuclear Research) (article, 2021-03-11)
Field: Materials Science — Biomaterials

Minimalist Tissue Engineering Approaches Using Low Material-Based Bioengineered Systems From an “over-engineering” era in which biomaterials played a central role, now it is observed to the emergence of “developmental” tissue engineering (TE) strategies which rely on an integrative cell-material perspective that paves the way for cell self-organization. The current challenge is to engineer the microenvironment without hampering the spontaneous collective arrangement ability of cells, while simultaneously providing biochemical, geometrical, and biophysical cues that positively influence tissue healing. These efforts have resulted in the development of low-material based TE strategies focused on minimizing the amount of biomaterial provided to the living key players of the regenerative process. Through a “minimalist-engineering” approach, the main idea is to fine-tune the spatial balance occupied by the inanimate region of the regenerative niche toward maximum actuation of the key living components during the healing process. Tissue engineering ; Computer science ; Engineering ; Systems engineering ; Biomedical engineering Electrospun Nanofibers in Biomedical Applications
Authors: Natalia Michalak | Tomasz Ossowski | Zygmunt Miłosz | Maurício J. Prieto | Ying Wang | Mirosław Werwiński | Višnja Babačić | Francesca Genuzio | L. Vattuone | A. Kiejna | Thomas Schmidt | Mikołaj Lewandowski
Source: arXiv (Cornell University) (preprint, 2021-05-04)
Field: Materials Science — Materials Chemistry

Real-time observation of Ostwald ripening in an oxide-on-metal system: Understanding the mechanisms that drive the size and structure of oxide species in "inverse" catalysts Oxides-on-metals are the well-known inverse catalysts. Fundamental knowledge on the structural transformations that occur in such systems under oxidizing and reducing conditions is crucial for maximizing their catalytic activity. Sintering of oxide species is one of the effects that may, on one hand, lead to catalyst deactivation, but on the other constitutes a powerful means for fine-tuning their size and structure - which is one of the major challenges in the field. In this Letter, we show that the structure of well-dispersed bilayer iron monoxide (FeO) islands grown on Ru(0001), which constitutes a model inverse catalyst, can be optimized by thermally-driven sintering and phase transition. The structural transformation occurs via the Ostwald ripening mechanism, as observed in real time using in situ low energy electron microscopy (LEEM). The structure of the islands before and after the transformation is determined using ex situ experimental methods, as well as theoretical calculations. Ostwald ripening ; Catalysis ; Oxide ; Sintering ; Oxidizing agent ; Materials science ; Bilayer ; Chemical physics ; Chemical engineering ; Transition metal ; Metal ; Inverse ; Nanotechnology ; Chemistry ; Metallurgy ; Membrane ; Organic chemistry Catalytic Processes in Materials Science ; Electrocatalysts for Energy Conversion ; Catalysts for Methane Reforming
Authors: Z. Osváth | Dániel Zámbó | Attila Sulyok | András Pálinkás | András Deák
Source: Carbon Trends (article, 2021-06-26)
Field: Materials Science — Materials Chemistry

Tuning the nanoscale rippling of graphene with PEGylated gold nanoparticles and ion irradiation Here we report a new method combining strain and defect engineering for the periodic modulation of the graphene nanoscale rippling. First, gold nanoparticles of 16 nm in diameter were synthesized by seed-mediated, wet-chemical approach, and thiol-terminated polyethylene glycol (mPEG-SH) molecules were grafted onto their surface. High-density monolayers of the PEGylated gold nanoparticles were successfully prepared on Si substrates by the Langmuir-Blodgett technique. Graphene grown by chemical vapour deposition was transferred onto the nanoparticle monolayer, and characterized by atomic force microscopy, scanning tunneling microscopy, as well as Raman spectroscopy. The induced nanoscale rippling of graphene was fine-tuned by Ar+ ion irradiation. Graphene ; Monolayer ; Materials science ; Raman spectroscopy ; Colloidal gold ; Rippling ; Nanoscopic scale ; Nanotechnology ; Nanoparticle ; Scanning tunneling microscope ; Chemical vapor deposition ; Polyethylene glycol ; Chemical engineering ; Optics Graphene research and applications ; Graphene and Nanomaterials Applications ; Carbon Nanotubes in Composites