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Iron-based trinuclear metal-organic nanostructures on a surface with local charge accumulation

Coordination chemistry relies on harnessing active metal sites within organic matrices. Polynuclear complexes—where organic ligands bind to several metal atoms—are relevant due to their electronic ... supramolecular chemistry on a noble metal surface—one-dimensional metal-organic nanostructures composed of terpyridine (tpy)-based molecules coordinated with well-defined polynuclear iron clusters. Combining low

Over 1000-fold enhancement of upconversion luminescence using water-dispersible metal-insulator-metal nanostructures

are attached to plasmonic nanostructures to enhance their photoluminescence (PL) emission. However, current wet-chemistry techniques suffer from large inhomogeneity and thus low enhancement is achieved ... polyvinyl alcohol (PVA) and dispersed in water. Overall, the fabrication process has a few, relatively simple steps and does not require any complicated wet-chemistry techniques usually associated with

Photo-tautomerization of acetaldehyde as a photochemical source of formic acid in the troposphere

Organic acids play a key role in the troposphere, contributing to atmospheric aqueous-phase chemistry, aerosol formation, and precipitation acidity. Atmospheric models currently account for less than ... pathways to an atmospheric chemistry box model (Master Chemical Mechanism) demonstrates increased formic acid concentrations by a factor of ~1.7 in the polluted troposphere and a factor of ~3 under pristine

Fluorine-free water-in-ionomer electrolytes for sustainable lithium-ion batteries

incorporating this electrolyte provided an average discharge voltage > 1.5 V and a specific energy of 77 Wh kg−1, while for an alternative cell chemistry, i.e., TiO2/LiMn2O4, a further enhanced average output ... . R. China 2 Department of Chemistry, University of Cambridge , Lensfield Road, Cambridge CB2 1EW , UK 3 University Grenoble Alpes, CEA, CNRS, SyMMES , F-38000 Grenoble , France 4 MEET Battery Research

Plasmonic hot electron transport drives nano-localized chemistry

to electromagnetic near-field maps, has been elusive. Here we spatially map hot-electron-driven reduction chemistry with 15 nm resolution as a function of time and electromagnetic field polarization ... transport from high-field regions, paves the way for improving efficiency in hot-carrier extraction science and nanoscale regio-selective surface chemistry. Introduction Nanostructured materials that

Stereoselective oxidative glycosylation of anomeric nucleophiles with alcohols and carboxylic acids

Oligosaccharides, one of the most abundant biopolymers, are involved in numerous biological processes. Although many efforts have been put in preparative carbohydrate chemistry, achieving optimal ... and evidence for internal return from an intimate ion-molecule pair. J. Am. Chem. Soc. 117, 3360–3367 (1995). Article Google Scholar55. Ochiai, M. Hypervalent iodine chemistry. Top. Curr. Chem. 224, 6

Multifunctional sequence-defined macromolecules for chemical data storage

automated protecting-group free, two-step iterative protocol based on thiolactone chemistry. Tandem mass spectrometry techniques have been explored to provide detailed analysis of the oligomer sequences. We ... , Polymer Chemistry Research Group, Centre of Macromolecular Chemistry (CMaC), Ghent University , Krijgslaan 281 S4bis, 9000 Ghent , Belgium 1 Department of Biochemistry and Microbiology, Laboratory for

Surface chemistry governs cellular tropism of nanoparticles in the brain

fraction varied with particle chemistry. While 32% of the tumour cells were associated with PLA NPs, only 11% were associated with PLA?PEG or PLA?HPG NPs, and up to 76% were associated with PLA?HPG?CHO NPs ... . Soc . 135 , 1438 - 1444 ( 2013 ). 43. Walkey , C. D. , Olsen , J. B. , Guo , H. , Emili , A. & Chan , W. C. Nanoparticle size and surface chemistry determine serum protein adsorption and macrophage

Tropical peatland carbon storage linked to global latitudinal trends in peat recalcitrance

(sub)tropical regions remains enigmatic. Here we examined peat and plant chemistry across a latitudinal transect from the Arctic to the tropics. Near-surface low-latitude peat has lower carbohydrate and ... Civil, Construction, and Environmental Engineering , North Carolina , USA 6 Department of Chemistry and Biochemistry, Florida State University , Tallahassee, FL 32306 , USA 7 Department of Microbiology

Selective N-terminal acylation of peptides and proteins with a Gly-His tag sequence

Methods for site-selective chemistry on proteins are in high demand for the synthesis of chemically modified biopharmaceuticals, as well as for applications in chemical biology, biosensors and more ... ; solvent B, acetonitrile containing 0.1% formic acid. The column was eluted using a linear gradient from 5 to 100% of solvent B. Some short peptides (Table 1) were analyzed on analytical HPLC (Dionex

Phase-controlled Fourier-transform spectroscopy

Fourier-transform spectroscopy (FTS) has been widely used as a standard analytical technique over the past half-century. FTS is an autocorrelation-based technique that is compatible with both ... in the fields of ourier-transform spectroscopy (FTS) has provided solutions chemistry, pharmacy, medicine, biology, and physics including material science1?3. It enables the simultaneous identification

Single crystal toroidal diamond anvils for high pressure experiments beyond 5 megabar

Static compression experiments over 4 Mbar are rare, yet critical for developing accurate fundamental physics and chemistry models, relevant to a range of topics including modeling planetary

Highly selective transition-metal-free transamidation of amides and amidation of esters at room temperature

Amide chemistry has an essential role in the synthesis of high value molecules, such as pharmaceuticals, natural products, and fine chemicals. Over the past years, several examples of transamidation ... XR = NR2R3, OR2 R2, R3 = N-/O-activating substituents T in chemistry and biology1?3. The amide linkage is essential he amide bond is the most fundamental functional group for the structure of peptides

Assigning the absolute configuration of single aliphatic molecules by visual inspection

Deciphering absolute configuration of a single molecule by direct visual inspection is the next step in compound identification, with far-reaching implications for medicinal chemistry, pharmacology ... only after fitting molecular orientation to the crystal polar axis7. Since the time of Pasteur’s experiment, various analytical techniques have been perfected to help determine the absolute

Direct electric field imaging of graphene defects

the atomic electric fields of Stone–Wales defects and nanopores in graphene. Our results open the way to directly examine the local chemistry of the defective structures in materials at atomistic ... . This result opens a new capability to investigate the local chemistry of atomistic defects in materials and might shed light on our understanding of material properties at the level of single atoms

In situ click chemistry generation of cyclooxygenase-2 inhibitors

, also termed as in situ click chemistry, we describe the discovery of two highly potent and selective cyclooxygenase-2 isozyme inhibitors. The in vivo anti-inflammatory activity of these two novel small ... appropriate chemical building blocks from a pool of chemicals to build its own highly potent inhibitor. Herein, with the use of kinetic target-guided synthesis, also termed as in situ click chemistry, we

Proton enhanced dynamic battery chemistry for aprotic lithium–oxygen batteries

provoked a range of discussions on the role of water and its impact on batteries. In this work, a distinct battery chemistry that prevails in water-contaminated aprotic lithium–oxygen batteries is revealed ... hydroperoxide with triiodide exhibits a faster kinetics, which enables a considerably lower overpotential during the charging process. The battery chemistry unveiled in this mechanistic study could provide

The photoregulation of a mechanochemical polymer scission

Control over mechanochemical polymer scission by another external stimulus may offer an avenue to further advance the fields of polymer chemistry, mechanochemistry, and materials science. Herein, we ... , Raita Goseki, Daisuke Aoki & Hideyuki OtsukaDepartment of Chemistry, Rikkyo University, 3-34-1 Nishi-Ikebukuro, Toshima-ku, Tokyo, 171-8501, JapanMasakazu Morimoto AuthorsSearch for Jumpei Kida in:Nature

Intermolecular selective carboacylation of alkenes via nickel-catalyzed reductive radical relay

radical chemistry with nickel catalysis. This reaction manifold utilizes a radical relay strategy involving radical addition to an alkene followed by alkyl radical capture by an acyl-nickel complex to forge ... the last decade, nickel-catalyzed cross-coupling has emerged as a powerful tool to forge C−C bonds in chemical synthesis50,51,52. Particularly, the merger of radical chemistry with nickel catalysis has

Simultaneous complementary photoswitching of hemithioindigo tweezers for dynamic guest relocalization

Remote control of complex molecular behavior and function is one key problem in modern chemistry. Using light signaling for this purpose has many advantages, however the integration of different ... same solution. This approach should provide a powerful tool for the construction of sophisticated, integrated, and multi-responsive smart molecular systems in any application driven field of chemistry. G