jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Nguyen, Hoai Nam
Source: theses.fr (ABES) (article, 2023-12-12)
Field: Chemistry — Organic Chemistry

Photopolymères réactivables pour la fabrication additive 3D : Dde la synthèse aux applications en photopolymérisation à un et deux photons médiée par les nitroxydes Aujourd’hui, la polymérisation de la VAT basée sur la fabrication additive en tant que technologie d’impression 3D a particulièrement attiré l’attention avec une réduction significative de la barrière d’entrée en termes de coût et de temps. En outre, des méthodes de photo-RDRP fondées sur des RAFT à médiation photographique, des ATRP à médiation photographique et des NMP2 dans la polymérisation à la VAT ont récemment été considérées comme un outil électrique pour produire des matériaux avancés dotés de chaînes de polymères réactives, qui permettent aux modifications des structures, propriétés et fonctionnalités des objets imprimés en 3D. Parmi ces méthodologies de photo-RDRP, NMP2 a émergé comme une technique appropriée pour la fabrication de micro- et nanostructures depuis le mono-la nature constitutive des alkoxyamines photosensibles est régulièrement utilisée dans les résines photodurcissables sans l’ajout de complexes métalliques et de composés colorés, en particulier dans des conditions d’absorption à deux photons. Toutefois, seulement deux alkoxyamines photosensibles portant de la benzophénone ont été trouvées jusqu’à maintenant dans la microfabrication fondée sur la polymérisation à un seul photon et à deux photons, malgré que la benzophénone soit un chromophore pauvre pour l’absorption de photons et le photoclivage de la liaison >NO−C sont en concurrence avec les species secondaires qui conduisent au faible rendement du nitroxyde généré. Dans ce manuscrit, nous visons ainsi la synthèse de nouvelles alkoxyamines photosensibles avec la haute sélectivité de la liaison alkoxyamine et la polymérisation polyvalente entre un et deux photons dans le contexte des techniques photo-RDRP. Les propriétés d’absorbance et les processus de photodissociation de Tacrine, D-π-A Tacrine et D-π-A Quinoline sont étudiés par spectroscopie UV/visible et spectroscopie de résonance paramagnétique électronique pour une application potentielle dans la photopolymérisation par nitroxyde. Les candidats prometteurs sont évalués la possibilité de fabriquer des macrostructures et des microstructures portant les caractères "vivants", ainsi que la modification de la surface de ces macros et microstructures fabriquées dans le cadre du NMP2 par "vivants" caractères sur leur surface sans l’ajout externe de photoinitiateurs dans des conditions de polymérisation à un et deux photons Manufacturing process ; Ultraviolet radiation ; Beam splitter Photopolymerization techniques and applications ; Additive Manufacturing and 3D Printing Technologies ; Advanced Polymer Synthesis and Characterization
Authors: Yang Chen | Huawei Hu | Cheng Qian | Yaozu Liao
Source:  (preprint, 2023-07-28)
Field: Materials Science — Materials Chemistry

Hollow sp2-conjugated covalent organic framework encapsulating thiophene-based photosensitizer for enhanced visible-light-driven hydrogen evolution Vinylene-linked covalent organic frameworks (COFs) have gained increasing attention for photocatalytic hydrogen evolution. However, the photocatalytic activity of vinylene-linked COFs has been restricted due to low exciton dissociation efficiency and wide band gap. Herein, we fabricated a novel p-n type Z-scheme heterostructure, g2T-T@HCOFs, through the hybridization of vinylene-linked COFs with a hollow structure and thiophene-based photosensitizer (g2T-T) using a template method and post-encapsulating modification. The hollow-structured HCOFs enable uniform encapsulation of the g2T-T both within their channels and on their surfaces, which facilitates the formation of a firm and stable interface between n-type HCOF and p-type g2T-T. Therefore, the encapsulation of g2T-T enables the realization of a Z-scheme pathway for efficient charge separation and transfer, leading to enhanced electron accumulation within the HCOFs during water splitting. Consequently, the obtained p-n type Z-scheme heterostructure g2T-T@HCOFs exhibit a remarkable 5.5-fold enhancement in visi-ble-light-induced hydrogen evolution activity compared to the pristine COF. Photosensitizer ; Heterojunction ; Materials science ; Photocatalysis ; Thiophene ; Covalent bond ; Exciton ; Photochemistry ; Dissociation (chemistry) ; Chemical engineering ; Conjugated system ; Nanotechnology ; Optoelectronics ; Polymer ; Catalysis ; Chemistry ; Organic chemistry ; Physics Covalent Organic Framework Applications ; Advanced Photocatalysis Techniques ; Metal-Organic Frameworks: Synthesis and Applications
Authors: Mishtha Fiyatillah | S. N. Sabki | A. H. Norzilah | L. K. Wisnu Kita | Muhammad Idris | Norinsan Kamil Othman | Alhan Farhanah Abd Rahim
Source: International Journal of Nanoelectronics and Materials (IJNeaM) (article, 2023-12-26)
Field: Materials Science — Materials Chemistry

Controlled Growth of Carbon Nanofibers (CNFs) on Graphene Carbon nanofibers (CNFs) have superior properties such as high conductivity, good mechanical strength, high specific surface area, and chemical stability. CNFs-graphene hybrid material can be used as a high-quality electrode in electronics applications. In the CNFs on graphene synthesis, the growth parameters must be well controlled. This work observes the evolution of the CNF's growth on graphene on Ni at reaction temperatures of 800oC and 860oC and at different reaction times of 30 min, 60 min, and 120 min. This research aims to find suitable conditions for obtaining controllable growth of CNFs on graphene. Based on the SEM measurement, it was found that the 860oC reaction temperature at 60 min and 120 min reaction time led to longer and smaller widths of CNFs with high coverage and distribution on graphene. The CNFs on graphene formation were confirmed by the XRD analysis. Graphene ; Carbon nanofiber ; Materials science ; Carbon fibers ; Nanotechnology ; Chemical engineering ; Electrode ; Conductivity ; Composite material ; Composite number ; Chemistry ; Carbon nanotube Graphene research and applications ; Graphene and Nanomaterials Applications ; Supercapacitor Materials and Fabrication
Authors: Silvia Nuti | Adrián Fernández‐Lodeiro | Lidia E. Chinchilla | Ana B. Hungría | José Luís Capelo | Carlos Lodeiro | Javier Fernández‐Lodeiro
Source: ChemRxiv (preprint, 2023-05-24)
Field: Materials Science — Materials Chemistry

Synthesis and Structural Characterization of Branched Bimetallic AuPd Nanoparticles with highly tunable optical response Bimetallic nanostructures composed of gold (Au) and palladium (Pd) have garnered increased interest for their application in heterogeneous catalysis. This study reports a simple strategy for manufacturing Au@Pd bimetallic branched nanoparticles (NPs), which offer a tuneable optical response, using polyallylamine-stabilized branched AuNPs as template cores for Pd over-growth. The palladium content can be altered by manipulating the concentration of PdCl42- and ascorbic acid (AA) that are injected, which permit an overgrowth of Pd shell up to ca. 2 nm thick. The homogeneous distribution of Pd at the surfaces of Au NPs can be carried out regardless of their size or branching degree, which allows an adjustment of the plasmon response in the near-infrared (NIR) spectral range. As proof of concept, the nano-enzymatic activity of pure gold and gold-palladium NPs was compared, exploring their Peroxidase-like activity in the oxidation of TMB. The bimetallic AuPd nanoparticles demonstrate an increase in catalytic properties attributed to the presence of palladium at the surface of gold. Bimetallic strip ; Palladium ; Catalysis ; Materials science ; Ascorbic acid ; Nanoparticle ; Branching (polymer chemistry) ; Homogeneous ; Plasmon ; Metal ; Nanostructure ; Nanotechnology ; Chemical engineering ; Chemistry ; Metallurgy ; Organic chemistry ; Composite material ; Optoelectronics Advanced Nanomaterials in Catalysis ; Gold and Silver Nanoparticles Synthesis and Applications ; Nanocluster Synthesis and Applications
Authors: Marek Ekielski | Weronika Głowadzka | Karolina Bogdanowicz | Michał Rygała | Monika Mikulicz | Patrycja Śpiewak | Marcin Kowalski | Marcin Gębski | M. Motyka | Anna Szerling | Tomasz Czyszanowski
Source: arXiv (Cornell University) (preprint, 2023-08-04)
Field: Materials Science — Surfaces, Coatings and Films

Monolithic High Contrast Grating Integrated with Metal: Infrared Electrode with Exceptionally High Conductivity and Transmission The design of transparent conductive electrodes (TCEs) for optoelectronic devices requires a trade-off between high conductivity or transmittivity, limiting their efficiency. This paper demonstrates a novel approach to fabricating TCEs that effectively alleviates this trade-off: a monolithic GaAs high contrast grating integrated with metal (metalMHCG). The metalMHCG enables higher electrical conductivity than other TCEs, while providing transmissive and antireflective properties. We focus on infrared spectrum TCEs, which are essential for sensing, thermal imaging, and automotive applications. However, due to elevated free carrier absorption they are much more demanding than TCEs for the visible spectrum. We demonstrate 75% absolute transmittiance of unpolarized light, resulting in 108% transmittance relative to plain GaAs substrate. We achieved even larger absolute transmittance of polarized light, reaching 92% or 133% relative transmittance. Despite record high transmittance, the sheet resistance of the metalMHCG is several times lower than any other TCE, ranging from 0.5 to 1 Ohm/Sq. Transmittance ; Materials science ; Optoelectronics ; Sheet resistance ; Grating ; Anti-reflective coating ; Infrared ; Electrode ; Absorption (acoustics) ; Visible spectrum ; Optics ; Substrate (aquarium) ; Nanotechnology ; Chemistry ; Physics ; Composite material Optical Coatings and Gratings ; Photonic and Optical Devices ; Semiconductor Lasers and Optical Devices
Authors: Et al. P.Mathiyalagan
Source: International Journal on Recent and Innovation Trends in Computing and Communication (article, 2023-04-30)
Field: Materials Science — Surfaces, Coatings and Films

Bio functional Surface Alteration Process for Inorganic and Metal Materials Derived from Polydopamine This research presents a novel polydopamine-derived biofunction alterationprocedure for inorganic and metal materials. The procedure involves a series of steps, including soaking the clean materials in a dopamine alkaline aqueous solution, oxidizing the materials to form a polydopamine alteration layer, performing thermal oxidation to enhance the reactivity and stability of the layer, and immersing the treated materials in a biofunctional molecular solution to obtain a biofunction simulate alteration layer. The polydopamine alteration layer obtained through this procedure exhibits excellent anti-deformation performance and reactivity, allowing for the immobilization of bioactive molecules on the material surface. The simplicity, mild conditions, and ease of implementation make this procedure highly practical. Metal ; Process (computing) ; Surface (topology) ; Materials science ; Nanotechnology ; Chemical engineering ; Chemistry ; Computer science ; Metallurgy ; Mathematics ; Engineering Polymer Surface Interaction Studies ; Bone Tissue Engineering Materials ; Advanced Polymer Synthesis and Characterization
Authors: Lidija‐Marija Tumir | Dijana Saftić | Ivo Crnolatac | Željka Ban | Matea Maslać | Stefanie Griesbeck | Todd B. Marder | Ivo Piantanida
Source: Molecules (article, 2023-05-25)
Field: Chemistry — Organic Chemistry

The Nature of the (Oligo/Hetero)Arene Linker Connecting Two Triarylborane Cations Controls Fluorimetric and Circular Dichroism Sensing of Various ds-DNAs and ds-RNAs A series of tetracationic bis-triarylborane dyes, differing in the aromatic linker connecting two dicationic triarylborane moieties, showed very high submicromolar affinities toward ds-DNA and ds-RNA. The linker strongly influenced the emissive properties of triarylborane cations and controlled the fluorimetric response of dyes. The fluorene-analog shows the most selective fluorescence response between AT-DNA, GC-DNA, and AU-RNA, the pyrene-analog's emission is non-selectively enhanced by all DNA/RNA, and the dithienyl-diketopyrrolopyrrole analog's emission is strongly quenched upon DNA/RNA binding. The emission properties of the biphenyl-analog were not applicable, but the compound showed specific induced circular dichroism (ICD) signals only for AT-sequence-containing ds-DNAs, whereas the pyrene-analog ICD signals were specific for AT-DNA with respect to GC-DNA, and also recognized AU-RNA by giving a different ICD pattern from that observed upon interaction with AT-DNA. The fluorene- and dithienyl-diketopyrrolopyrrole analogs were ICD-signal silent. Thus, fine-tuning of the aromatic linker properties connecting two triarylborane dications can be used for the dual sensing (fluorimetric and CD) of various ds-DNA/RNA secondary structures, depending on the steric properties of the DNA/RNA grooves. Linker ; DNA ; RNA ; Fluorene ; Circular dichroism ; Chemistry ; Fluorescence ; Pyrene ; Stereochemistry ; Nucleic acid secondary structure ; Biophysics ; Crystallography ; Combinatorial chemistry ; Photochemistry ; Biochemistry ; Biology ; Organic chemistry ; Polymer Organoboron and organosilicon chemistry ; Chemical Synthesis and Analysis ; Luminescence and Fluorescent Materials
Authors: Rao M. Uppu | Frank R. Fronczek
Source: IUCrData (article, 2023-01-06)
Field: Chemistry — Physical and Theoretical Chemistry

1<i>H</i>-Benzo[<i>g</i>]pteridine-2,4-dione The structure of the title compound, C<sub>10</sub>H<sub>6</sub>N<sub>4</sub>O<sub>2</sub>, reported by Smalley <i>et al.</i> [(2021). <i>Cryst. Growth Des.</i> <b>22</b>, 524-534] from powder diffraction data and <sup>15</sup>N NMR spectroscopy, is confirmed using low-temperature data from a twinned crystal. The tautomer in the solid state is alloxazine (1<i>H</i>-benzo[<i>g</i>]pteridine-2,4-dione) rather than isoalloxazine (10<i>H</i>-benzo[<i>g</i>]pteridine-2,4-dione). In the extended structure, the mol-ecules form hydrogen-bonded chains propagating in the [01] direction through alternating centrosymmetric <i>R</i> <sup>2</sup> <sub>2</sub>(8) rings with pairwise N-H⋯O inter-actions and centrosymmetric <i>R</i> <sup>2</sup> <sub>2</sub>(8) rings with pairwise N-H⋯N inter-actions. The crystal chosen for data collection was found to be a non-merohedral twin (180° rotation about [001]) in a 0.446 (4):0.554 (6) domain ratio. Pteridine ; Chemistry ; Crystallography ; Crystal structure ; Tautomer ; Molecule ; Stereochemistry ; Hydrogen bond ; Crystal (programming language) Crystallography and molecular interactions ; Crystal structures of chemical compounds ; X-ray Diffraction in Crystallography
Authors: Ibrahim A. Alnaser | Md Irfanul Haque Siddiqui | Muhammad Omer Aijaz | Seong Baek Yang | Mohammad Rezaul Karim
Source: Journal of Disability Research (review, 2023-01-01)
Field: Materials Science — Materials Chemistry

A Review of Children’s Prosthetic Self-hygiene Using Antibacterial Silver Nanoparticles (AgNPs) Sports prostheses represent a critical facet in enhancing the mobility and quality of life for children with limb loss. However, prolonged usage of these prosthetic devices introduces substantial challenges related to hygiene and the heightened risk of infection. This comprehensive review endeavors to delve into the untapped potential of utilizing antibacterial silver nanoparticles (AgNPs) to foster self-hygiene practices in pediatric sports prostheses. AgNPs have emerged as a compelling area of research, largely attributable to their formidable antibacterial properties, offering revolutionary prospects in the realm of antibacterial therapy. Central to this exploration is an in-depth analysis of their antibacterial activity, elucidating their intricate mechanisms of action against bacterial agents. The unique physicochemical attributes, characterized by their diminutive size and expansive surface area, synergize to elevate their antibacterial efficacy significantly. The antibacterial mechanisms involve the controlled release of silver ions, which disrupt bacterial cell membranes, impede vital cellular processes, and provoke oxidative stress within the pathogens. Moreover, they exhibit the propensity for synergistic interactions when employed in tandem with conventional antibiotics, thereby positioning themselves as promising candidates for combination therapy. This review further encompasses a comprehensive survey of diverse methodologies employed for the synthesis of AgNPs and their multifarious application in various domains, including the realm of prosthetics and medicine. Nevertheless, as with any emerging technology, the implementation of AgNPs does not come without its challenges. Issues pertinent to the stability of AgNPs, potential toxicity concerns, and the development of bacterial resistance necessitate critical consideration for their successful integration into pediatric sports prostheses. In summation, AgNPs epitomize a compelling arsenal of antibacterial agents, propelling the possibilities of innovative therapeutic strategies in the battle against bacterial infections. This review underscores their remarkable potential while underscoring the imperative need for further research and development to unlock their full efficacy in the context of pediatric sports prostheses and beyond. Silver nanoparticle ; Nanotechnology ; Realm ; Antibacterial activity ; Expansive ; Chemistry ; Nanoparticle ; Materials science ; Biology ; Political science Nanoparticles: synthesis and applications ; Graphene and Nanomaterials Applications ; Polymer Surface Interaction Studies
Authors: B. Katz | Vincent H. Crespi
Source: arXiv (Cornell University) (preprint, 2023-05-20)
Field: Materials Science — Materials Chemistry

Healing of a Topological Scar: Coordination Defects in a Honeycomb Lattice A crystal structure with a point defect typically returns to its ideal local structure upon moving a few bond lengths away from the defect; topological defects such as dislocations or disclinations also heal rapidly in this regard. Here we describe a simple point defect -- a two-fold atom incorporated at the growth edge of a 2D hexagonal honeycomb material -- whose healing may require a defect complex with 50 or more atoms. $\textit{Topologically}$ the two-fold atom disappears into a single 'long bond' between its neighbors, thereby inducing a pentagonal disclination. However, $\textit{chemically}$ this disclination occupies as much physical space as a six-fold ring. This incompatibility of chemistry and topology can cause a ''ringing'' of the Gaussian curvature that creates an expansive healing region and may even spawn a semi-infinite grain boundary propagating outwards from the topological scar. Disclination ; Crystallographic defect ; Topological defect ; Topology (electrical circuits) ; Materials science ; Hexagonal crystal system ; Gaussian curvature ; Lattice (music) ; Curvature ; Crystallography ; Condensed matter physics ; Geometry ; Physics ; Mathematics ; Chemistry ; Combinatorics Covalent Organic Framework Applications ; Supramolecular Self-Assembly in Materials ; Pickering emulsions and particle stabilization
Authors: Vo Khuong Dien | Phạm Thị Bích Thảo | Nguyen Thi Han | Duy Khanh Nguyen | Le Võ Phương Thuận | Ming‐Fa Lin | Nguyễn Thành Tiên
Source: arXiv (Cornell University) (preprint, 2023-06-08)
Field: Materials Science — Materials Chemistry

Unlocking the Potential of GeS Monolayer: Strain-Enabled Control of Electronic Transports and Exciton Radiative Lifetimes Monolayer germanium sulfide is gaining significant attention for its exceptional anisotropic electronic conductance, notable excitonic effects, and wide range of potential applications. In our study, we used density functional theory, many-body perturbation theory, and non-equilibrium Green function to investigate electronic transport properties and exciton radiative lifetime of single-layer germanium sulfide. Our theoretical findings showed that applying up to 8 percent compressive strain increased carrier mobility by nearly threefold, and thus, dramatically enhance the device's current intensity. Moreover, we observed that strain engineering allowed fine-tuning of the electron-hole recombination time. At 6 percent tensile strain, the effective radiative lifetime was as short as 19 picoseconds, which is 4.5 times faster than the intrinsic state and 80 times faster than at 8 percent compressive strain. These results highlight the potential of strain engineering to customize the electronic and optical properties of GeS monolayer for specific electronic, optoelectronic, and photovoltaic device requirements Monolayer ; Materials science ; Exciton ; Germanium ; Picosecond ; Optoelectronics ; Strain engineering ; Radiative transfer ; Electron mobility ; Molecular physics ; Nanotechnology ; Condensed matter physics ; Chemistry ; Optics ; Physics ; Silicon 2D Materials and Applications ; Perovskite Materials and Applications ; Semiconductor Quantum Structures and Devices
Authors: Julia Arnanz | Fernando Romeo‐Gella | Juan J. Nogueira | Inés Corral
Source: ChemRxiv (preprint, 2023-03-31)
Field: Materials Science — Materials Chemistry

In Silico Investigation of the Photoisomerization Mechanism of Push-Push Azoderivatives The design of novel chromophores showing specific photophysical traits is nowadays crucial for the development of new dyes and optical devices. Azobenzene derivatives comprise the largest fraction of the industrial dyes and remain one of the main functions to be employed in the design of general-purpose photoactivated switches. In this context, we have investigated the optical and photoisomerization properties of two push-push azo derivatives, from a purely theoretical perspective, to outline a mechanistic landscape that can contribute to setting the grounds for the future goal of formulating dyes with particular photophysical properties. Both derivatives show downhill excited-state potential energy surfaces, hinting at fast photoactivated isomerization. In addition, both the trans and cis forms show nearly complementary absorption spectra leading to discriminatory color and differential excitation possibilities. Additionally, the reverse cis to trans ground state thermal isomerization reactions show higher energy barriers than the parent azobenzene molecule, supporting their potential use in different technological applications. Photoisomerization ; Isomerization ; Azobenzene ; Chromophore ; Context (archaeology) ; Photochemistry ; Excited state ; Chemistry ; Molecule ; Materials science ; Combinatorial chemistry ; Organic chemistry ; Physics Photochromic and Fluorescence Chemistry ; Radical Photochemical Reactions ; Luminescence and Fluorescent Materials