jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Yan Peng | Hagen Kaemmerer | Annie K. Powell
Source: Chemistry - A European Journal (review, 2021-09-28)
Field: Materials Science — Electronic, Optical and Magnetic Materials

From the {Fe<sup>III</sup><sub>2</sub>Ln<sub>2</sub>} Butterfly's Perspective: the Magnetic Benefits and Challenges of Cooperativity within 3 d–4 f Based Coordination Clusters In this Review we discuss the tuning handles which can be used to steer the magnetic properties of Fe<sup>III</sup> -4 f "butterfly" compounds. The majority of presented compounds were produced in the context of project A3 "Di- to tetranuclear compounds incorporating highly anisotropic paramagnetic metal ions" within the SFB/TRR88 "3MET". These contain {Fe<sup>III</sup> <sub>2</sub> Ln<sub>2</sub> } cores encapsulated in ligand shells which are easy to tune in a "test-bed" system. We identify the following advantages and variables in such systems: (i) the complexes are structurally simple usually with one crystallographically independent Fe<sup>III</sup> and Ln<sup>III</sup> , respectively. This simplifies theory and anaylsis; (ii) choosing Fe allows <sup>57</sup> Fe Mössbauer spectroscopy to be used as an additional technique which can give information about oxidation levels and spin states, local moments at the iron nuclei and spin-relaxation and, more importantly, about the anisotropy not only of the studied isotope, but also of elements interacting with this isotope; (iii) isostructural analogues with all the available (i. e. not Pm) 4 f ions can be synthesised, enabling a systematic survey of the influence of the 4 f ion on the electronic structure; (iv) this cluster type is obtained by reacting [Fe<sup>III</sup> <sub>3</sub> O(O<sub>2</sub> CR)<sub>6</sub> (L)<sub>3</sub> ](X) (X=anion, L=solvent such as H<sub>2</sub> O, py) with an ethanolamine-based ligand L' and lanthanide salts. This allows to study analogues of [Fe<sup>III</sup> <sub>2</sub> Ln<sub>2</sub> (μ<sub>3</sub> -OH)<sub>2</sub> (L')<sub>2</sub> (O<sub>2</sub> CR)<sub>6</sub> ] using the appropriate iron trinuclear starting materials. (v) the organic main ligand can be readily functionalised, facilitating a systematic investigation of the effect of organic substituents on the ligands on the magnetic properties of the complexes. We describe and discuss 34 {M<sup>III</sup> <sub>2</sub> Ln<sub>2</sub> } (M=Fe or in one case Al) butterfly compounds which have been reported up to 2020. The analysis of these gives perspectives for designing new SMM systems with specific electronic and magnetic signatures. Isostructural ; Ligand (biochemistry) ; Crystallography ; Lanthanide ; Chemistry ; Context (archaeology) ; Cluster (spacecraft) ; Ion ; Coordination sphere ; Paramagnetism ; Physics ; Crystal structure ; Organic chemistry ; Condensed matter physics Magnetism in coordination complexes ; Lanthanide and Transition Metal Complexes ; Metal-Catalyzed Oxygenation Mechanisms
Authors: Boyang Mao | Benjamin J. Hodges | Craig Franklin | David G. Calatayud | Sofia I. Pascu
Source: Frontiers in Chemistry (review, 2021-10-01)
Field: Materials Science — Materials Chemistry

Self-Assembled Materials Incorporating Functional Porphyrins and Carbon Nanoplatforms as Building Blocks for Photovoltaic Energy Applications As a primary goal, this review highlights the role of supramolecular interactions in the assembly of new sustainable materials incorporating functional porphyrins and carbon nanoplatforms as building blocks for photovoltaics advancements. Photovoltaics ; Nanotechnology ; Photovoltaic system ; Carbon fibers ; Materials science ; Organic solar cell ; Supramolecular chemistry ; Self-assembly ; Chemistry ; Engineering ; Molecule ; Organic chemistry Porphyrin and Phthalocyanine Chemistry ; Advanced battery technologies research ; Supercapacitor Materials and Fabrication
Authors: Renato L. Carvalho | Gleiston G. Dias | Cynthia L. M. Pereira | Pintu Ghosh | Debabrata Maiti | Eufrânio N. da Silva Júnior
Source: Journal of the Brazilian Chemical Society (article, 2021-01-01)
Field: Chemistry — Organic Chemistry

A Catalysis Guide Focusing on C–H Activation Processes From the recent development of catalytically controlled C-H activation with amenable synthetic routes obviating many challenges, the demand for this strategy has raised significantly to perform complex organic transformations. The impact of the achieved results in both homogeneous and heterogeneous catalysis reflects its efficacy in modern synthetic chemistry. A consolidated report and guidance of the methodologies involved in the previous and ongoing research in this domain would be very useful for the researchers to focus on more specific and selective C-H activation reactions to access desired complex molecular scaffolds. The perspective of this review is to contribute to the scientific community with examples, tips and details of modern development in this field and with a complete illustration of the routes which may be effective for planning of the ubiquitous C-H bond activation and its use for synthesis of relevant organic molecules. Homogeneous ; Nanotechnology ; Chemistry ; Domain (mathematical analysis) ; Organic synthesis ; Combinatorial chemistry ; Biochemical engineering ; Catalysis ; Computer science ; Materials science ; Engineering ; Organic chemistry ; Physics ; Mathematics Catalytic C–H Functionalization Methods ; Asymmetric Hydrogenation and Catalysis ; Synthesis and Catalytic Reactions
Authors: Natanael Fernandes | Carolina F. Rodrigues | Duarte de Melo‐Diogo | Ilídio J. Correia | André F. Moreira
Source: Nanomaterials (article, 2021-07-28)
Field: Materials Science — Materials Chemistry

Optimization of the GSH-Mediated Formation of Mesoporous Silica-Coated Gold Nanoclusters for NIR Light-Triggered Photothermal Applications Cancer light-triggered hyperthermia mediated by nanomaterials aims to eliminate cancer cells by inducing localized temperature increases to values superior to 42 °C, upon irradiation with a laser. Among the different nanomaterials with photothermal capacity, the gold-based nanoparticles have been widely studied due to their structural plasticity and advantageous physicochemical properties. Herein, a novel and straightforward methodology was developed to produce gold nanoclusters coated with mesoporous silica (AuMSS), using glutathione (GSH) to mediate the formation of the gold clusters. The obtained results revealed that GSH is capable of triggering and control the aggregation of gold nanospheres, which enhanced the absorption of radiation in the NIR region of the spectra. Moreover, the produced AuMSS nanoclusters mediated a maximum temperature increase of 20 °C and were able to encapsulate a drug model (acridine orange). In addition, these AuMSS nanoclusters were also biocompatible with both healthy (fibroblasts) and carcinogenic (cervical cancer) cells, at a maximum tested concentration of 200 μg/mL. Nevertheless, the AuMSS nanoclusters' NIR light-triggered heat generation successfully reduced the viability of cervical cancer cells by about 80%. This confirms the potential of the AuMSS nanoclusters to be applied in cancer therapy, namely as theragnostic agents. Nanoclusters ; Photothermal therapy ; Nanomaterials ; Materials science ; Mesoporous silica ; Mesoporous material ; Nanotechnology ; Nanoparticle ; Photothermal effect ; Colloidal gold ; Nanocages ; Chemistry ; Organic chemistry Nanocluster Synthesis and Applications ; Nanoplatforms for cancer theranostics ; Advanced Nanomaterials in Catalysis
Authors: Tomoyuki Koga | Shinya Kingetsu | Nobuyuki Higashi
Source: International Journal of Molecular Sciences (article, 2021-04-26)
Field: Materials Science — Biomaterials

Supramolecular Nanofibers from Collagen-Mimetic Peptides Bearing Various Aromatic Groups at N-Termini via Hierarchical Self-Assembly Self-assembly of artificial peptides has been widely studied for constructing nanostructured materials, with numerous potential applications in the nanobiotechnology field. Herein, we report the synthesis and hierarchical self-assembly of collagen-mimetic peptides (CMPs) bearing various aromatic groups at the <i>N</i>-termini, including 2-naphthyl, 1-naphtyl, anthracenyl, and pyrenyl groups, into nanofibers. The CMPs (<i>R</i>-(GPO)<i><sub>n</sub></i>: <i>n</i> > 4) formed a triple helix structure in water at 4 °C, as confirmed via CD analyses, and their conformations were more stable with increasing hydrophobicity of the terminal aromatic group and peptide chain length. The resulting pre-organized triple helical CMPs showed diverse self-assembly into highly ordered nanofibers, reflecting their slight differences in hydrophobic/hydrophilic balance and configuration of aromatic templates. TEM analysis demonstrated that 2Np-CMP<i><sub>n</sub></i> (<i>n</i> = 6 and 7) and Py-CMP<i><sub>6</sub></i> provided well-developed natural collagen-like nanofibers and An-CMP<i><sub>n</sub></i> (<i>n</i> = 5-7) self-assembled into rod-like micelle fibers. On the other hand, 2Np-CMP<i><sub>5</sub></i> and 1Np-CMP<i><sub>6</sub></i> were unable to form nanofibers under the same conditions. Furthermore, the Py-CMP<i><sub>6</sub></i> nanofiber was found to encapsulate a guest hydrophobic molecule, Nile red, and exhibited unique emission behavior based on the specific nanostructure. In addition to the ability of CMPs to bind small molecules, their controlled self-assembly enables their versatile utilization in drug delivery and wavelength-conversion nanomaterials. Nanofiber ; Supramolecular chemistry ; Self-assembly ; Molecule ; Peptide ; Chemistry ; Amphiphile ; Drug delivery ; Nile red ; Template ; Stereochemistry ; Combinatorial chemistry ; Nanotechnology ; Materials science ; Copolymer ; Organic chemistry ; Polymer ; Biochemistry ; Fluorescence Supramolecular Self-Assembly in Materials ; Collagen: Extraction and Characterization ; Bone and Dental Protein Studies
Authors: Loredana Amigoni | Lucia Salvioni | Barbara Sciandrone | Marco Giustra | Chiara Pacini | Paolo Tortora | Davide Prosperi | Miriam Colombo | Maria Elena Regonesi
Source: Nanomaterials (article, 2021-06-11)
Field: Materials Science — Materials Chemistry

Impact of Tuning the Surface Charge Distribution on Colloidal Iron Oxide Nanoparticle Toxicity Investigated in Caenorhabditis elegans Assessing the toxic effect in living organisms remains a major issue for the development of safe nanomedicines and exposure of researchers involved in the synthesis, handling and manipulation of nanoparticles. In this study, we demonstrate that <i>Caenorhabditis elegans</i> could represent an in vivo model alternative to superior mammalians for the collection of several physiological functionality parameters associated to both short-term and long-term effects of colloidally stable nanoparticles even in absence of microbial feeding, usually reported to be necessary to ensure appropriate intake. Contextually, we investigated the impact of surface charge on toxicity of superparamagnetic iron oxide coated with a wrapping polymeric envelop that confers them optimal colloidal stability. By finely tuning the functional group composition of this shallow polymer-obtaining totally anionic, partially pegylated, partially anionic and partially cationic, respectively-we showed that the ideal surface charge organization to optimize safety of colloidal nanoparticles is the one containing both cationic and anionic groups. Our results are in accordance with previous evidence that zwitterionic nanoparticles allow long circulation, favorable distribution in the tumor area and optimal tumor penetration and thus support the hypothesis that zwitterionic iron oxide nanoparticles could be an excellent solution for diagnostic imaging and therapeutic applications in nanooncology. Nanoparticle ; Surface charge ; Cationic polymerization ; Iron oxide nanoparticles ; Nanotechnology ; Colloid ; Caenorhabditis elegans ; Materials science ; Iron oxide ; In vivo ; Polymer ; Surface modification ; Biophysics ; Chemistry ; Chemical engineering ; Biology ; Biochemistry ; Organic chemistry ; Polymer chemistry Nanoparticles: synthesis and applications
Authors: Alison E. Ondrus | Tianyi Zhang
Source: Synlett (article, 2021-03-15)
Field: Chemistry — Organic Chemistry

Structure, Bonding, and Photoaffinity Labeling Applications of Dialkyldiazirines Abstract Dialkyldiazirine photoaffinity probes are unparalleled tools for the study of small molecule–protein interactions. Here we summarize the basic principles of structure, bonding, and photoreactivity of dialkyldiazirines, current methods for their synthesis, and their practical application in photoaffinity labeling experiments. We demonstrate the unique utility of dialkyldiazirine probes in the context of our recent photoaffinity crosslinking-mass spectrometry analysis to reveal a hidden cholesterol binding site in the Hedgehog morphogen proteins. 1 Introduction 2 Structure, Bonding, and Spectral Properties 3 Photoreactivity 4 Synthesis 5 Application in Photoaffinity Labeling 6 Discovery of a Cholesterol–Hedgehog Protein Interface 7 Conclusions and Outlook Photoaffinity labeling ; Chemistry ; Context (archaeology) ; Morphogen ; Hedgehog ; Combinatorial chemistry ; Stereochemistry ; Binding site ; Biochemistry ; Signal transduction Synthesis and Catalytic Reactions ; Chemical Synthesis and Analysis ; Click Chemistry and Applications
Authors: Benoît Colasson | Thomas Devic | Joël Gaubicher | Charlotte Martineau | Philippe Poizot | Vincent Sarou‐Kanian
Source: Chemistry - A European Journal (article, 2021-04-08)
Field: Materials Science — Materials Chemistry

Dual Electroactivity in a Covalent Organic Network with Mechanically Interlocked Pillar[5]arenes The synthesis and characterization of a polyrotaxanated covalent organic network (CON) based on the association between the viologen and pillar[5]arene (P[5]OH) units are reported. The mechanical bond allows for the irreversible insertion of n-type redox centers (P[5]OH macrocycles) within a pristine structure based on p-type viologen redox centers. Both redox units are active on a narrow potential range and, in water, the presence of P[5]OH greatly increases the electroactivity of the material. Covalent bond ; Viologen ; Pillar ; Redox ; Chemistry ; Polymer chemistry ; Network covalent bonding ; Stereochemistry ; Photochemistry ; Organic chemistry Covalent Organic Framework Applications ; Supramolecular Chemistry and Complexes ; Luminescence and Fluorescent Materials
Authors: Ashwanth Subramanian | Nikhil Tiwale | Won‐Il Lee | Chang‐Yong Nam
Source: Frontiers in Nanotechnology (article, 2021-12-06)
Field: Materials Science — Materials Chemistry

Templating Functional Materials Using Self-Assembled Block Copolymer Thin-Film for Nanodevices The nanomorphologies and nanoarchitectures that can be synthesized using block copolymer (BCP) thin-film self-assembly have inspired a variety of new applications, which offer various advantages, such as, small device footprint, low operational power and enhanced device performance. Imperative for these applications, however, is the ability to transform these small polymeric patterns into useful inorganic structures. BCP-templated inorganic nanostructures have shown the potential for use as active materials in various electronic device applications, including, field-effect transistors, photodetectors, gas sensors and many more. This article reviews various strategies that have been implemented in the past decade to fabricate devices at nanoscale using block copolymer thin films. Materials science ; Copolymer ; Nanotechnology ; Thin film ; Nanoscopic scale ; Nanostructure ; Transistor ; Polymer ; Electrical engineering ; Composite material ; Engineering Block Copolymer Self-Assembly ; Machine Learning in Materials Science ; Advanced Polymer Synthesis and Characterization
Authors: Noelia Faginas‐Lago | Yusuf Bramastya Apriliyanto | Andrea Lombardi
Source: The European Physical Journal D (article, 2021-05-01)
Field: Materials Science — Materials Chemistry

Confinement of $$\hbox {CO}_{2}$$ inside carbon nanotubes Abstract We propose a preliminary study based on molecular dynamics calculations to investigate the adsorption of pure $$\hbox {CO}_{2}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mtext>CO</mml:mtext> <mml:mn>2</mml:mn> </mml:msub> </mml:math> on flexible single-walled carbon nanotubes (SWCNTs) of different sizes. The adsorption capacities of SWCNTs were simulated and the effect of chirality and diameter of SWCNTs was assessed, to check them as sizable carbon structured materials suitable for $$\hbox {CO}_{2}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mtext>CO</mml:mtext> <mml:mn>2</mml:mn> </mml:msub> </mml:math> confinement and storage. The potential energy surfaces, describing the intermolecular interactions involving $$\hbox {CO}_{2}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mtext>CO</mml:mtext> <mml:mn>2</mml:mn> </mml:msub> </mml:math> -SWCNT and $$\hbox {CO}_{2}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mtext>CO</mml:mtext> <mml:mn>2</mml:mn> </mml:msub> </mml:math> - $$\hbox {CO}_2$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mtext>CO</mml:mtext> <mml:mn>2</mml:mn> </mml:msub> </mml:math> pairs, have been described specifically by adopting the improved lennard jones model potential. The intramolecular interactions within the SWCNT were considered explicitly since they are responsible for out-of-plane movements of carbon atoms and the flexibility of nanotubes. These well-formulated potentials are well capable of defining $$\hbox {CO}_{2}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mtext>CO</mml:mtext> <mml:mn>2</mml:mn> </mml:msub> </mml:math> confinement through physisorption and guarantee a quantitative description and realistic results for the dynamics of the interactions. The flexible SWCNTs can adsorb up to 35 wt% at 273 K, a property that makes them potentially versatile materials competitive with other carbon-derived adsorbents to cope with $$\hbox {CO}_{2}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mtext>CO</mml:mtext> <mml:mn>2</mml:mn> </mml:msub> </mml:math> gas emission. Graphic abstract Algorithm ; Materials science ; Computer science Carbon Nanotubes in Composites ; Phase Equilibria and Thermodynamics ; Quantum, superfluid, helium dynamics
Authors: Thomas S. Heiderscheit | Shunpei Oikawa | Stephen Sanders | Hiro Minamimoto | Emily K. Searles | Christy F. Landes | Kei Murakoshi | Alejandro Manjavacas | Stephan Link
Source: The Journal of Physical Chemistry Letters (article, 2021-03-05)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Tuning Electrogenerated Chemiluminescence Intensity Enhancement Using Hexagonal Lattice Arrays of Gold Nanodisks Electrogenerated chemiluminescence (ECL) microscopy shows promise as a technique for mapping chemical reactions on single nanoparticles. The technique's spatial resolution is limited by the quantum yield of the emission and the diffusive nature of the ECL process. To improve signal intensity, ECL dyes have been coupled with plasmonic nanoparticles, which act as nanoantennas. Here, we characterize the optical properties of hexagonal arrays of gold nanodisks and how they impact the enhancement of ECL from the coreaction of tris(2,2'-bipyridyl)dichlororuthenium(II) hexahydrate and tripropylamine. We find that varying the lattice spacing results in a 23-fold enhancement of ECL intensity because of increased dye-array near-field coupling as modeled using finite element method simulations. Chemiluminescence ; Materials science ; Plasmon ; Nanoparticle ; Emission intensity ; Lattice (music) ; Colloidal gold ; Hexagonal lattice ; Electrochemistry ; Coupling (piping) ; Luminescence ; Hexagonal crystal system ; Optoelectronics ; Analytical Chemistry (journal) ; Photochemistry ; Molecular physics ; Nanotechnology ; Electrode ; Chemistry ; Crystallography ; Physical chemistry ; Condensed matter physics ; Physics Gold and Silver Nanoparticles Synthesis and Applications ; Advanced biosensing and bioanalysis techniques ; Quantum Dots Synthesis And Properties
Authors: Rafaela A. L. Silva | Manuel Almeida
Source: Journal of Materials Chemistry C (article, 2021-01-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Spin-ladder behaviour in molecular materials Spin-ladders are fascinating quantum magnetic systems. Their structural and magnetic properties and the possibilities offered by molecular units of different nature and crystal engineering tools to prepare molecular spin-ladders are discussed. Spin (aerodynamics) ; Spin engineering ; Materials science ; Molecular magnets ; Condensed matter physics ; Chemical physics ; Spin polarization ; Magnetic field ; Physics ; Magnetization ; Quantum mechanics ; Electron Magnetism in coordination complexes ; Organic and Molecular Conductors Research ; Physics of Superconductivity and Magnetism
Authors: Darya Meisak | J. Macutkevič | Algirdas Selskis | P. Kuzhir | J. Banys
Source: Nanomaterials (article, 2021-02-23)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Dielectric Relaxation Spectroscopy and Synergy Effects in Epoxy/MWCNT/Ni@C Composites The dielectric/electric properties of the Ni@C (carbon-coated Ni)/epoxy composites and Ni@C/MWCNTs (multi-walled carbon nanotubes)/epoxy composites loaded with fixed MWCNTs amount just below the percolation threshold (0.09 vol.%) and Ni@C at different concentrations up to 1 vol.% were investigated in broad frequency (20 Hz-40 GHz) and temperature (30 K-500 K) regions. In composites with the only Ni@C nanoparticles, the electrical percolation threshold was determined between 10 and 15 vol.%. Above the percolation threshold the dielectric permittivity (ε') and the electrical conductivity (σ) of the composites loaded with Ni@C only are high enough, i.e., ε' = 10<sup>5</sup> and σ = 0.6 S/m at 100 Hz for composites with 30 vol.% Ni@C, to be used for electromagnetic shielding applications. The annealing to 500 K was proved to be an effective and simple tool to decrease the percolation threshold in epoxy/Ni@C composites. For hybrid composites series an optimal concentration of Ni@C (0.2 vol.%) was determined, leading to the conductivity absolute values several orders of magnitude higher than that of a composite filled with MWCNTs only. The synergy effects of using both fillers have been discussed. Below room temperature the electrical transport is mainly governed by epoxy resin compression in all composites, while the electron tunnelling was observed only in hybrid composites below 200 K. At higher temperatures (above 400 K), in addition to the nanoparticles redistribution effects, the electrical conductivity of epoxy resin makes a significant contribution to the total composite conductivity. The dielectric relaxation spectroscopy allows estimating the nanoparticles distributions in polymer matrix and could be used as the non-destructive and fast alternate to microscopy techniques for general polymer composite fabrication control. Materials science ; Percolation threshold ; Composite material ; Epoxy ; Carbon nanotube ; Dielectric ; Electrical resistivity and conductivity ; Composite number ; Conductivity ; Permittivity ; Nanocomposite ; Nanoparticle ; Nanotechnology ; Chemistry Electromagnetic wave absorption materials ; Dielectric materials and actuators ; Conducting polymers and applications