2,708 results match your criteria: "National Institute for Materials science NIMS[Affiliation]"

Diels-Alder chemistry was exploited to develop a remote-controllable drug release platform on magnetic nanoparticles (MNPs). For this purpose, MNPs were decorated with anionic poly(styrenesulfonic acid--furfuryl methacrylate) (poly(SS--FMA)) and cationic poly(allylamine hydrochloride) by layer-by-layer assembly. The decorated MNPs successfully underwent DA reaction to produce covalent bonding between FMA (diene) and maleimide (dienophile)-terminated model drug.

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γ-Butyrolactone Synthesis from Allylic Alcohols Using the CO Radical Anion.

Precis Chem

March 2024

Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Kita 21, Nishi 10, Kita-ku, Sapporo, Hokkaido 001-0021, Japan.

γ-Butyrolactone structures are commonly found in various natural products and serve as crucial building blocks in organic synthesis. Consequently, the development of methods for synthesizing γ-butyrolactones has garnered significant interest within the organic synthesis community. In this study, we present a direct and highly efficient approach for the synthesis of γ-butyrolactones from allylic alcohols.

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Lasing in an assembled array of silver nanocubes.

Nanoscale Horiz

December 2024

Institute of Materials Science, Kaunas University of Technology, K. Baršausko St. 59, Kaunas LT-51432, Lithuania.

We demonstrate a surface lattice resonance (SLR)-based plasmonic nanolaser that leverages bulk production of colloidal nanoparticles and assembly on templates with single particle resolution. SLRs emerge from the hybridization of the plasmonic and photonic modes when nanoparticles are arranged into periodic arrays and this can provide feedback for stimulated emission. It has been shown that perfect arrays are not a strict prerequisite for producing lasing.

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The formation of the topological surface state originates from bulk band inversion at the top of the valence band and the bottom of the conduction band. The transition between normal and topological insulators is known as a topological phase transition. Here we show spin-polarized electronic states of Pb-based ternary topological insulators Pb(BiSb)Te (x = 0.

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Spin reorientation and the interplay of magnetic sublattices in ErCuMnMnO.

Acta Crystallogr B Struct Sci Cryst Eng Mater

December 2024

Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, United Kingdom.

Article Synopsis
  • The study investigates the magnetic properties of ErCuMnMnO using techniques like magnetic susceptibility, specific heat, and neutron powder diffraction, revealing four distinct magnetic phase transitions.
  • The complex structure of quadruple perovskites leads to interactions between various magnetic sublattices, which cause spin reorientation transitions due to competing magnetic forces within the manganese sublattice.
  • At low temperatures, one Er sublattice becomes magnetically ordered, while the other remains non-magnetic until a final phase transition, highlighting intricate interactions between transition metal and rare-earth sublattices, which poses challenges for understanding the entire RCuMnMnO family.
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Possible Superconductivity for Layered Metal Boride Carbide Compounds MBC (M = Alkali, Alkaline-Earth, or Rare-Earth Metals).

Inorg Chem

November 2024

CNRS, Ecole Nationale Supérieure de Chimie de Rennes (ENSCR), Institut des Sciences Chimiques de Rennes (ISCR), UMR 6226, Univ Rennes, F-35000 Rennes, France.

The possible emergence of superconductivity in layered metal boride carbide compounds MBC (M = Sc, Y, Be, Ca) was investigated using density functional theory calculations upon the topology of a boron-carbon network and the nature of the metal. ScBC and YBC show metallic and superconductive properties with low critical temperatures (s). The semiconducting BeBC compound may show superconductivity upon carrier doping with a high of 47.

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For olfactory sensors, clear differentiation of complex odour samples requires diverse information. To obtain such information, hardware modifications, such as introducing additional channels with different physical/chemical properties, are usually needed. In this study, we present a new approach to augmenting the sensing signals of an olfactory sensor by modulating the flow rate of the carrier gas.

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Magnetotransport, the response of electrical conduction to external magnetic field, acts as an important tool to reveal fundamental concepts behind exotic phenomena and plays a key role in enabling spintronic applications. Magnetotransport is generally sensitive to magnetic field orientations. In contrast, efficient and isotropic modulation of electronic transport, which is useful in technology applications such as omnidirectional sensing, is rarely seen, especially for pristine crystals.

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Catalytic asymmetric fragmentation of cyclopropanes.

Science

October 2024

Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Sapporo 001-0021, Japan.

The stereoselective activation of alkanes constitutes a long-standing and grand challenge for chemistry. Although metal-containing enzymes oxidize alkanes with remarkable ease and selectivity, chemical approaches have largely been limited to transition metal-based catalytic carbon-hydrogen functionalizations. Alkanes can be protonated to form pentacoordinated carbonium ions and fragmented into smaller hydrocarbons in the presence of strong Brønsted acids.

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As a kind of star materials, two-dimensional (2D) nanomaterials have attracted tremendous attention for their unique structures, excellent performance and wide applications. In recent years, layered rare earth-based or doped nanomaterials have become a new important member of the 2D nanomaterial family and have attracted significant interest, especially layered rare earth hydroxides (LREHs) and layered rare earth-doped perovskites with anion-exchangeability and exfoliative properties. In this review, we systematically summarize the synthesis, exfoliation, fabrication and biomedical applications of 2D rare earth nanomaterials.

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Plasmonic nanoparticles (NPs) with chiral geometries have wide applications from chiral molecular sensing to enantioselective catalysis. The synthesis of chiral plasmonic nanoparticles using circularly polarized light (CPL) has attracted a considerable amount of attention because it eliminates the need for chiral molecules. However, NPs need to be immobilized on a solid substrate during synthesis.

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Wearable thermoelectric generators provide a reliable power generation method for self-powered wearable electronic devices. However, there has been a lack of research regarding the comfort of wearable thermoelectric generators. Here we propose a design for a comfortable wearable thermoelectric generators system with high output power based on sandwiched thermoelectric model.

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The extracellular matrix determines cell morphology and stiffness by manipulating the cytoskeleton. The impacts of extracellular matrix cues, including the mechanical and topographical cues on microtubules and their role in biological behaviors, are previously studied. However, there is a lack of understanding about how microtubules (MTs) are affected by environmental chemical cues, such as extracellular matrix density.

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High-Yield Synthesis Route, Post-Synthesis Treatment, and Insights into the Photoluminescence and Magnetic Properties of Tricopper(I) Melaminate Cu(CNH).

Inorg Chem

October 2024

Section for Solid State and Theoretical Inorganic Chemistry, Institute of Inorganic Chemistry, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen Germany.

A novel and more efficient synthesis of Cu(CNH) is presented through a salt-metathesis reaction using copper(I) chloride and sodium hydrogen cyanamide. This synthesis yields a melaminate trianion through the cyclotrimerization of (HNCN) ions, offering an alternative route to the deprotonation of melamine for synthesizing melaminate. The reaction is analyzed via differential thermal analysis.

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Growth Mechanism of Carbon Nanotubes Revealed by in situ Transmission Electron Microscopy.

Small

December 2024

Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang, 110016, China.

Elucidating the growth mechanism of carbon nanotubes (CNTs) is critical to obtaining CNTs with desired structures and tailored properties for their practical applications. With atomic resolution imaging, in situ transmission electron microscopy (TEM) has been a key technique to reveal the microstructure and dynamics of CNTs in real time. In this review, recent advances in the development of in situ TEM with different types of environmental reactors will be introduced.

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Reference-free quantitative mass spectrometry in the presence of nonlinear distortion caused by chemical reactions among constituents.

Analyst

October 2024

Data-driven Polymer Design Group, Research Center for Macromolecules and Biomaterials, National Institute for Materials Science (NIMS), 1-2-1, Sengen, Tsukuba, Ibaraki 305-0047, Japan.

Materials performance is primarily influenced by chemical composition, making compositional analysis (CA) essential in materials science. Traditional quantitative mass spectrometry, which deconvolutes analyte spectra into reference spectra, struggles with reactive systems where spectral variations occur, such as peak shifts and new peak emergences. Additionally, obtaining reference spectra for all pure constituents is often impractical.

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Nitrides and oxynitrides isostructural to α-SiN (-α-SiAlON,  = Sr, Ca, Li) possess superb thermally stable photoluminescence (PL) properties, making them reliable phosphors for high-power solid-state lighting. However, the synthesis of phase-pure Sr-α-SiAlON still remains a great challenge and has only been reported for Sr below 1.35 at.

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Unilamellar MnO nanosheets confined Ru-clusters combined with pulse electrocatalysis for biomass electrooxidation in neutral electrolytes.

Sci Bull (Beijing)

January 2025

State Key Laboratory of Chem/Bio-Sensing and Chemometrics, Advanced Catalytic Engineering Research Center of the Ministry of Education, College of Chemistry and Chemical Engineering, The National Supercomputer Centers in Changsha, Hunan University, Changsha 410082, China. Electronic address:

The electrochemical oxidation of 5-hydroxymethylfurfural (HMFOR) in alkaline electrolyte is a promising strategy for producing high-value chemicals from biomass derivatives. However, the disproportionation of aldehyde groups under strong alkaline conditions and the polymerization of HMF to form humic substances can impact the purity of 2,5-furandicarboxylic acid (FDCA) products. The use of neutral electrolytes offers an alternative environment for electrolysis, but the lack of OH ions in the electrolyte often leads to low current density and low yields of FDCA.

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Structure and Defect Identification at Self-Assembled Islands of CO Using Scanning Probe Microscopy.

ACS Nano

October 2024

Departamento de Física Teórica de la Materia Condensada, Universidad Autónoma de Madrid, Madrid 28049, Spain.

Understanding how carbon dioxide (CO) behaves and interacts with surfaces is paramount for the development of sensors and materials to attempt CO mitigation and catalysis. Here, we combine simultaneous atomic force microscopy (AFM) and scanning tunneling microscopy (STM) using CO-functionalized probes with density functional theory (DFT)-based simulations to gain fundamental insight into the behavior of physisorbed CO molecules on a gold(111) surface that also contains one-dimensional metal-organic chains formed by 1,4-phenylene diisocyanide (PDI) bridged by gold (Au) adatoms. We resolve the structure of self-assembled CO islands, both confined between the PDI-Au chains as well as free-standing on the surface and reveal a chiral arrangement of CO molecules in a windmill-like structure that encloses a standing-up CO molecule and other foreign species existing at the surface.

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Enormous swelling of layered host compounds in an aqueous solution of various amines has been investigated as an important step in the synthesis of molecularly thin 2D nanosheets. However, a complete understanding of the reaction process has not been attained, which is the barrier for producing high-quality unilamellar nanosheets. Here, the swelling and delamination behaviors of platelet single crystals of protonated layered metal oxides are systematically examined with a series of tetraalkylammonium (TAA) hydroxide solutions.

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Potential of Enzymatically Synthesized Hemozoin Analog as Th1 Cell Adjuvant.

Nanomaterials (Basel)

September 2024

Research Center for Macromolecules and Biomaterials, National Institute for Materials Science (NIMS), Tsukuba 305-0047, Japan.

Article Synopsis
  • Hemozoin (Hz) is a crystal made during malaria infection that activates immune cells, promoting the production of cytokines and chemokines, and is useful for developing adjuvants.
  • This study explored an enzymatic method for synthesizing Hz using a heme detoxification protein (HDP), which successfully produces an analog called esHz.
  • EsHz demonstrated the ability to stimulate immune responses in macrophages and human immune cells, enhancing specific types of antibodies in mice, indicating it could serve as an effective Th-1 cell adjuvant.
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The impact of contaminants on Copepod sp. and its molecular response is least explored, despite their abundance and dominance among invertebrates in aquatic environments. In the present investigation, , a cyclopoid zooplankton, was treated with selenium nanoparticles (SeNPs) to determine the associated biochemical changes, and the chronic exposure effects were recorded using transcriptomic analysis.

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Layered silicates, including clay minerals, can be used as liquid-phase adsorbents in many important applications. However, because their two-dimensional interlayer space is narrow and not entirely opened due to the presence of interlayer species, guest species are forced to penetrate while expanding the interlayer space, which limits their adsorption performances compared with microporous materials such as MOFs and zeolites. Herein, as reported for the adsorption of gaseous species on flexible MOFs, we report a layered silicate that exhibits gate-opening adsorption in liquid phases.

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The binary boron-rich compounds α-IrB and β-IrB, formerly denoted as α- and β-IrB, were synthesized both arc melting followed by annealing at 800 °C (900 °C) and high-temperature thermal treatment of mixtures of the elements. X-ray structure analysis of α-IrB was performed on a single crystal (space group 2/, = 10.5515(11) Å, = 2.

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Climate Change and Materials Criticality challenges are driving urgent responses from global governments. These global responses drive policy to achieve sustainable, resilient, clean solutions with Advanced Materials (AdMats) for industrial supply chains and economic prosperity. The research landscape comprising industry, academe, and government identified a critical path to accelerate the Green Transition far beyond slow conventional research through Digital Technologies that harness Artificial Intelligence, Smart Automation and High Performance Computing through Materials Acceleration Platforms, MAPs.

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