jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Kaihua Zhang | Xiaofeng Wang | Zhiruo Zhou | Jing Guo | Hao Liu | Yaxin Zhai | Yifan Yao | Kun Yang | Zebing Zeng
Source: Angewandte Chemie International Edition (article, 2024-10-18)
Field: Materials Science — Materials Chemistry

Facile Access to Phosphorus Ylide‐fused Heteroarenes Possessing Tunable Optoelectronic Properties and High Nonlinear Optical Performances We report here a novel family of ylidic P-heteroarenes (P1-P6), structurally featuring unique phosphonium cyclopentadienylide (P-Cp)-fused π-skeletons and synthetically prepared via an unexpected one-pot [2+3]/[3+3] phospha-annulation reaction. While the facile and modular synthesis allows the fine-tuning of their optical absorptions and redox properties, single-crystallographic and theoretical analysis of these P-heteroarenes further reveal that the fusion of P-Cp moiety leads to substantial intramolecular charge-separated features with high ylidic character values of up to 84 %. Benefitted from such dipolar structures, these P-heteroarenes not only allows stepwise electrophilic substitution reaction for further structural π-expansions, but also exhibit excellent nonlinear optical (NLO) responses and optical limiting (OL) performances comparable to or exceed those of C<sub>60</sub>. As a model compound, the persistent radical-anion salt of P5a was also prepared through chemical reduction, thus offering valuable insights into the electronic structures of reduced P-ylidic species. Our work not only established a highly efficient synthetic method toward new P-heteroarenes, but also provide fundamental understanding of those fused-ring ylidic P-heterocycles with promising NLO/OL applications. Moiety ; Ylide ; Phosphonium ; Intramolecular force ; Ion ; Nonlinear optical ; Materials science ; Limiting ; Combinatorial chemistry ; Chemistry ; Stereochemistry ; Polymer chemistry ; Organic chemistry ; Nonlinear system ; Physics Porphyrin and Phthalocyanine Chemistry ; Synthesis and Properties of Aromatic Compounds ; Organoboron and organosilicon chemistry
Authors: Claudia Harting | Attila Teleki | Marius Braakmann | Frank Jankowitsch | Ralf Takors
Source: Microbial Biotechnology (article, 2024-03-01)
Field: Materials Science — Materials Chemistry

Systemic intracellular analysis for balancing complex biosynthesis in a transcriptionally deregulated <i>Escherichia coli</i> <scp>l</scp> ‐Methionine producer l-Methionine (l-Met) has gained remarkable interest due to its multifaceted and versatile applications in the fields of nutrition, pharmaceuticals and clinical practice. In this study, the fluxes of the challenging l-Met biosynthesis in the producer strain Escherichia coli (E. coli) DM2853 were fine-tuned to enable improved l-Met production. The potential bottlenecks identified in sulfur assimilation and l-Met synthesis downstream of O-succinyl-l-homoserine (OSHS) were addressed by overexpressing glutaredoxin 1 (grxA), thiosulfate sulfurtransferase (pspE) and O-succinylhomoserine lyase (metB). Although deemed as a straightforward target for improving glucose-to-Met conversion, the yields remained at approximately 12%-13% (g/g). Instead, intracellular l-Met pools increased by up to four-fold with accelerated kinetics. Overexpression of the Met exporter ygaZH may serve as a proper valve for releasing the rising internal Met pressure. Interestingly, the export kinetics revealed maximum saturated export rates already at low growth rates. This scenario is particularly advantageous for large-scale fermentation when product formation is ideally uncoupled from biomass formation to achieve maximum performance within the technical limits of large-scale bioreactors. Escherichia coli ; Methionine ; Biosynthesis ; Biochemistry ; Chemistry ; Intracellular ; Fermentation ; Thiosulfate ; Sulfur ; Enzyme ; Gene ; Amino acid Enzyme Structure and Function ; Cancer Research and Treatments ; Amino Acid Enzymes and Metabolism
Authors: Dmitry Yu. Aleshin | Veronika V. Zlobina | Alexander S. Belov | Yan Z. Voloshin | Alexander A. Pavlov
Source: Russian Journal of Coordination Chemistry (article, 2024-02-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Influence of the Solvent Nature on the Spin Equilibrium in Solutions of the Cobalt(II) Phenylborate Hexa-n-Butylsulfide Clathrochelate by the Paramagnetic NMR Spectroscopy Data The spin state of the cobalt(II) phenylborate hexa-n-butylsulfide clathrochelate in solutions is studied by paramagnetic NMR spectroscopy. This cage complex is shown to undergo the temperature-induced spin transition in solvents of different nature (acetonitrile, chloroform, dichloromethane, and benzene). The previously developed method for an analysis of paramagnetic shifts in NMR spectra allows the determination of the thermodynamic parameters (enthalpy and entropy) of the spin equilibrium in the solutions. In spite of the conformational rigidity of the macrobicyclic tris(dioximate) molecules, substantial changes in the electronic structures and spin equilibrium parameters are observed depending on the polarity of the solvent used. This provides opportunities for fine tuning of spin switch characteristics by changing this parameter of the medium. Chemistry ; HEXA ; Cobalt ; Paramagnetism ; Solvent ; Nuclear magnetic resonance spectroscopy ; Spectroscopy ; Spin (aerodynamics) ; Physical chemistry ; Crystallography ; Inorganic chemistry ; Organic chemistry ; Condensed matter physics ; Quantum mechanics ; Thermodynamics ; Physics Magnetism in coordination complexes ; Advanced NMR Techniques and Applications ; Organic and Molecular Conductors Research
Authors: Anastasiia Sherstiuk | Marc Villabona | Agustı́ Lledós | Jordi Hernando | Rosa Marı́a Sebastián | Evamarie Hey‐Hawkins
Source: Dalton Transactions (article, 2024-01-01)
Field: Materials Science — Materials Chemistry

Amplified photomodulation of a bis(dithienylethene)-substituted phosphine Phosphine ligands play a crucial role in homogeneous catalysis, allowing fine-tuning of the catalytic activity of various metals by modifying their structure. An ultimate challenge in this field is to reach controlled modulation of catalysis <i>in situ</i>, for which the development of phosphines capable of photoswitching between states with differential electronic properties has been proposed. To magnify this light-induced behavior, in this work we describe a novel phosphine ligand incorporating two dithienylethene photoswitchable moieties tethered to the same phosphorus atom. Double photoisomerization was observed for this ligand, which remains unhindered upon gold(I) complexation. As a result, the preparation of a fully ring-closed phosphine isomer was accomplished, for which amplified variation of phosphorus electron density was verified both experimentally and by computational calculations. Accordingly, the presented molecular design based on multiphotochromic phosphines could open new ways for preparing enhanced photoswitchable catalytic systems. Phosphine ; Chemistry ; Organic chemistry ; Catalysis Photochromic and Fluorescence Chemistry ; Radical Photochemical Reactions ; Porphyrin and Phthalocyanine Chemistry
Authors: Andrés Serna Gutiérrez | Nicolás A. Cordero
Source: Crystals (article, 2024-03-28)
Field: Materials Science — Materials Chemistry

Mechanical Properties of Small Quasi-Square Graphene Nanoflakes The rise of straintronics—the possibility of fine-tuning the electronic properties of nanosystems by applying strain to them—has enhanced the interest in characterizing the mechanical properties of these systems when they are subjected to tensile (or compressive), shear and torsion strains. Four parameters are customarily used to describe the mechanical behavior of a macroscopic solid within the elastic regime: Young’s and shear moduli, the torsion constant and Poisson’s ratio. There are some relations among these quantities valid for elastic continuous isotropic systems that are being used for 2D nanocrystals without taking into account the non-continuous anisotropic nature of these systems. We present in this work computational results on the mechanical properties of six small quasi-square (aspect ratio between 0.9 and 1.1) graphene nanocrystals using the PM7 semiempirical method. We use the results obtained to test the validity of two relations derived for macroscopic homogeneous isotropic systems and sometimes applied to 2D systems. We show they are not suitable for these nanostructures and pinpoint the origin of some discrepancies in the elastic properties and effective thicknesses reported in the literature. In an attempt to recover one of these formulas, we introduce an effective torsional thickness for graphene analogous to the effective bending thickness found in the literature. Our results could be useful for fitting interatomic potentials in molecular mechanics or molecular dynamics models for finite carbon nanostructures, especially near their edges and for twisted systems. Graphene ; Square (algebra) ; Materials science ; Nanotechnology ; Composite material ; Mathematics ; Geometry Graphene research and applications ; Carbon Nanotubes in Composites ; Graphene and Nanomaterials Applications
Authors: Deepika Dhaterwal | Mahesh Matoria | Surender Kumar | Rajesh Kumar | Annu Dalal | Sonika Singh
Source: Transactions on Electrical and Electronic Materials (article, 2024-08-20)
Field: Materials Science — Materials Chemistry

Probe of Color Tunable Luminescence Attributes of YAlO3 Nanophosphor Through Co-doping of Eu3+ and Tb3+ Ions Materials science ; Luminescence ; Doping ; Ion ; Optoelectronics ; Organic chemistry Luminescence Properties of Advanced Materials ; Luminescence and Fluorescent Materials ; Radiation Detection and Scintillator Technologies
Authors: Wan‐Ting Chiu | Ryunosuke Hayakawa | Naoki Nohira | Masaki Tahara | Tomonari Inamura | Hideki Hosoda
Source: Materialia (article, 2024-07-29)
Field: Materials Science — Materials Chemistry

Mechanical properties of various thermomechanical processed Ti-Mo-Al-Zr and pseudo-binary (Ti-Zr)-Mo shape memory alloys for biomedical applications Materials science ; Thermomechanical processing ; Shape-memory alloy ; Metallurgy ; Composite material ; Microstructure Titanium Alloys Microstructure and Properties ; Bone Tissue Engineering Materials ; Advanced materials and composites
Authors: Samuel López-Blanco | Fernando Rubio‐Marcos | Andrea Barrón | Diego A. Ochoa | José E. García
Source: Journal of the European Ceramic Society (article, 2024-03-11)
Field: Materials Science — Materials Chemistry

Flash sintering of potassium-sodium niobate-based piezoceramics: Refining (micro)structure for properties enhancement Low-consumption ceramics processing routes are expected to replace conventional ones due to environmental concerns. In this context, flash sintering is garnering interest because it allows dense ceramics to be obtained in just a few minutes and at relatively low temperatures. This is particularly interesting for sintering alkaline-based compounds due to the easy volatilization of these elements. In this work, current-controlled flash sintering is used to obtain potassium-sodium niobate (KNN)-based piezoceramics with refined microstructure and suitable stoichiometry, leading to improved functional properties. KNN-based materials are currently outstanding lead-free piezoceramics, with their properties highly sensitive to the proper construction of the polymorphic phase boundary, as in the case of the first promising composition (K0.44Na0.52Li0.04)(Nb0.86Ta0.10Sb0.04)O3. Results of this work show that sintering parameters may determine the polymorphic behavior of this system, thereby evincing flash sintering allows polymorphic phase boundary to be fine-tuned. It is demonstrated that the convergence of microstructure refinement and compositional control holds the potential for enhancing properties through a proper electric current control during flash sintering. Sintering ; Materials science ; Microstructure ; Ceramic ; Potassium niobate ; Flash (photography) ; Mineralogy ; Composite material ; Optoelectronics ; Dielectric ; Ferroelectricity ; Optics Ferroelectric and Piezoelectric Materials ; Acoustic Wave Resonator Technologies ; Microwave Dielectric Ceramics Synthesis
Authors: Autchara Pangon | Supaphorn Kaewwong | Kamonchanok Srithai | Suttinun Phongtamrug
Source: Fibers and Polymers (article, 2024-01-22)
Field: Materials Science — Biomaterials

Emulsion Electrospun Polylactide/Sodium Alginate Nanofibrous Membranes with Rhinacanthus nasutus Extract for Natural Antibacterial Function Electrospinning ; Materials science ; Membrane ; Emulsion ; Absorption of water ; Chemical engineering ; Biodegradation ; Antibacterial activity ; Composite material ; Nuclear chemistry ; Polymer ; Organic chemistry ; Chemistry ; Bacteria Electrospun Nanofibers in Biomedical Applications ; biodegradable polymer synthesis and properties ; Advanced Sensor and Energy Harvesting Materials
Authors: M. Kriener | Takashi Koretsune | Ryotaro Arita | Yoshinori Tokura | Yasujiro Taguchi
Source: Science and Technology of Advanced Materials (article, 2024-10-08)
Field: Materials Science — Materials Chemistry

Enhancement of the thermoelectric figure of merit in the Dirac semimetal Cd <sub>3</sub> As <sub>2</sub> by band-structure and -filling control Topological materials attract a considerable research interest because of their characteristic band structure giving rise to various new phenomena in quantum physics. Besides this, they are tempting from a functional materials point of view: Topological materials bear potential for an enhanced thermoelectric efficiency because they possess the required ingredients, such as intermediate carrier concentrations, large mobilities, heavy elements etc. Against this background, this work reports an enhanced thermoelectric performance of the topological Dirac semimetal Cd<sub>3</sub>As<sub>2</sub> upon alloying the trivial semiconductor Zn<sub>3</sub>As<sub>2</sub>. This allows to gain fine-tuned control over both the band filling and the band topology in Cd<sub>3-<i>x</i></sub> Zn <sub><i>x</i></sub> As<sub>2</sub>. As a result, the thermoelectric figure of merit exceeds 0.5 around <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>x</mml:mi> <mml:mo>=</mml:mo> <mml:mn>0.6</mml:mn></mml:math> and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>x</mml:mi> <mml:mo>=</mml:mo> <mml:mn>1.2</mml:mn></mml:math> at elevated temperatures. The former is due to an enhancement of the power factor, while the latter is a consequence of a strong suppression of the thermal conductivity. In addition, in terms of first-principle band structure calculations, the thermopower in this system is theoretically evaluated, which suggests that the topological aspects of the band structure change when traversing <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>x</mml:mi> <mml:mo>=</mml:mo> <mml:mn>1.2</mml:mn></mml:math> . Semimetal ; Figure of merit ; Condensed matter physics ; Materials science ; Dirac (video compression format) ; Thermoelectric effect ; Electronic band structure ; Physics ; Engineering physics ; Band gap ; Optoelectronics ; Quantum mechanics Advanced Thermoelectric Materials and Devices ; Topological Materials and Phenomena ; Heusler alloys: electronic and magnetic properties
Authors: J.Q. Li | Sidra Parvez | Tong Shu
Source: Chemosensors (article, 2024-12-19)
Field: Materials Science — Materials Chemistry

Advancing Biosensing and Imaging with DNA-Templated Metal Nanoclusters: Synthesis, Applications, and Future Challenges—A Review Metal nanoclusters (MNCs) are emerging as a novel class of luminescent nanomaterials with unique properties, bridging the gap between individual atoms and nanoparticles. Among these, DNA-templated MNCs have gained significant attention due to the synergistic combination of MNCs’ properties (such as exceptional resistance to photostability, size-tunable emission, and excellent optical characteristics) with the inherent advantages of DNA, including programmability, functional modification, molecular recognition, biocompatibility, and water solubility. The programmability and biocompatibility of DNA offer precise control over the size, shape, and composition of MNCs, leading to tunable optical, electrical, and magnetic properties. This review delves into the complex relationship between DNA sequence, structure, and the resulting MNC properties. By adjusting parameters such as DNA sequence, length, and conformation, the size, morphology, and composition of the corresponding MNCs can be fine-tuned, enabling insights into how DNA structure influences the optical, electrical, and magnetic properties of MNCs. Finally, this review highlights the remarkable versatility and latest advancements of DNA-templated MNCs, particularly in biosensing and imaging, and explores their future potential to revolutionize biomedical applications. Nanoclusters ; Nanotechnology ; Nanomaterials ; Materials science ; Biocompatibility ; Biosensor ; DNA ; Chemistry Nanocluster Synthesis and Applications ; Advanced biosensing and bioanalysis techniques ; Advanced Nanomaterials in Catalysis
Authors: Noohul Alam | Towhidur Rahaman | Anish Kumar Das | Arun K. Pal | Ayan Datta | Soumya Jyoti Ray | Pradip Kumar Mondal | Maurizio Polentarutti | Sukhendu Mandal
Source: Small (article, 2024-12-10)
Field: Materials Science — Materials Chemistry

Inflection of Resistive Switching Behavior in Atomically Precise Silver Cluster‐Assembled Materials Abstract Bottom‐up design of electronic materials based on nanometer‐sized building blocks requires precise control over their self‐assembly process. Atomically precise metal nanoclusters (NCs) are the well‐characterized building blocks for crafting tunable nanomaterials. Here, a solution‐processed assembly of a newly synthesized molecular silver nanocluster ( 0 D Ag 12 ‐NC ) into a 1D nanocluster chain ( 1 D Ag 12 ‐CAM ) is mediated by 4,4′‐bipyridine linker Both 0 D Ag 12 ‐NC and 1 D Ag 12 ‐CAM consist of Ag 12 core that adopts the cuboctahedron geometry protected by organic ligands. The resistive switching devices are fabricated in a sandwich‐like structure of ITO (Indium tin oxide)/X/Ag (where X is either 0 D Ag 12 ‐NC or 1 D Ag 12 ‐CAM ). The device based on 1 D Ag 12 ‐CAM exhibited excellent resistive switching behaviour, enduring up to 1000 cycles and boasting a fivefold higher I on /I off ratio compared to the device based on the molecular 0 D Ag 12 ‐NC nanocluster. Furthermore, the device based on 1 D Ag 12 ‐CAM demonstrated negative differential resistance (NDR) phenomena, achieving a peak‐to‐valley ratio of 2.34 with a switching efficiency of 23 Ns. This work highlights the importance of interconnecting molecular nanoclusters into 1D nanocluster chains for fine‐tuning resistive memory properties in futuristic electronic appliances. Nanoclusters ; Nanomaterials ; Nanotechnology ; Materials science ; Cluster (spacecraft) ; Nanometre ; Self-assembly ; Computer science Nanocluster Synthesis and Applications ; Gold and Silver Nanoparticles Synthesis and Applications ; Advanced Nanomaterials in Catalysis
Authors: Marcelo Salas | Diana M. Arciniegas Jaimes | Valeria C. Fuertes | Eduardo Saavedra | Alejandro Pereira | Juan Escrig | Omar E. Linárez Pérez | Noelia Bajales
Source: The Journal of Physical Chemistry C (article, 2024-04-05)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Tuning Magnetic Properties of Co<sub><i>x</i></sub>Ni<sub>100–</sub><i><sub>x</sub></i> Nanodots: Micromagnetic Insights for Tailoring Enhanced Electrochemical Performance in Energy Storage Devices We conducted an integral study based on micromagnetic simulations and experiments to systematically investigate the quasi-static and dynamic magnetic characteristics of CoxNi100–x nanodots, varying the Co composition. We compared the magnetic properties of both ideal and real defective circular geometries, employing phase diagrams, hysteresis loops, and magnetization reversal modes for a comprehensive analysis. Our study highlights distinct alterations in coercivity and remanence between ideal and real defective geometries, while the S-mode of reversal is observed in both cases. Notably, our simulations underscore the remarkable sensitivity of magnetic properties to edge defects and the Co content in the alloy. This research underscores the essential role of micromagnetic simulations in tailoring the Co composition of the alloy, thereby fine-tuning the material’s magnetic hardness for enhanced performance in electrochemical applications, particularly as electrodes in energy storage devices. Nanodot ; Materials science ; Micromagnetics ; Magnetic storage ; Nanotechnology ; Electrochemistry ; Condensed matter physics ; Electrochemical energy storage ; Energy storage ; Optoelectronics ; Magnetization ; Engineering physics ; Supercapacitor ; Magnetic field ; Physics ; Chemistry ; Thermodynamics ; Electrode ; Physical chemistry Supercapacitor Materials and Fabrication ; Advancements in Battery Materials ; Advanced Memory and Neural Computing
Authors: Murtaza Bohra | Vidya Alman | M.A. Khan | Vidyadhar Singh | Evropi Toulkeridou | Panagiotis Grammatikopoulos
Source: Nano Select (article, 2024-02-05)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Analytical modeling of magnetocaloric effect in dense nanoparticle systems Abstract Determining the magnetocaloric effect (MCE) in dense nanoparticle systems (DNSs) poses a challenge due to the increased complexity of matter at the nanoscale. Given the interparticle magnetic interactions, diverse particle size and shape distributions, and the presence of inhomogeneous magnetic phases, selecting a suitable phenomenological model is essential to describe the temperature dependence of magnetic behavior in DNSs. Herein, we chose a cost‐effective Ni 100‐x Cr x DNS with adjustable magnetic transitions to showcase the resilience of the MCE across a broad temperature range (147–614 K). While the hyperbolic tangent model appears more fitting for materials with a single Curie temperature ( T C ), such as its parent bulk alloys, in the presence of a T C distribution a Gaussian distribution model proves to be better suited for DNSs. The latter model yields a magnetic entropy change, Δ S max = 0.09–0.15 J kg‐K −1 in the DNS at a tiny field of 0.1T. The correlations between the broadening of the MCE peak and T C distribution are attributed to the particle size distribution and chemical inhomogeneity present in the DNS, paving the way for fine‐tuning MCE‐related properties such as the relative cooling power (13.17–33.45 J kg −1 ) and adiabatic temperature change (0.03–0.17 K). Our methodology not only enhances the potential for designing innovative MCE materials with broader operating ranges but also validates the universality of our phenomenological model for other families of nanocrystalline/nanogranular oxides/alloys thin films. Magnetic refrigeration ; Materials science ; Condensed matter physics ; Curie temperature ; Nanocrystalline material ; Adiabatic process ; Universality (dynamical systems) ; Scaling ; Phenomenological model ; Atmospheric temperature range ; Isotropy ; Magnetic field ; Thermodynamics ; Statistical physics ; Physics ; Nanotechnology ; Magnetization ; Ferromagnetism ; Mathematics ; Quantum mechanics Magnetic and transport properties of perovskites and related materials ; Multiferroics and related materials ; Magnetic Properties of Alloys