Poly (vinylidene fluoride) (PVDF) matrix hybrid nanocomposites, featuring ferroelectric barium titanate (BT) nanoparticles and multi-walled carbon nanotubes (MWCNT) embedded in the polymer, were fabricated by a miscible-immiscible coagulation method followed by hot pressing. SEM images showed good distribution of the ceramic nanoparticles with very little particle agglomeration. The conductive MWCNT increased the charge storage ability of the matrix polymer by serving as a polarized charge transport phase for the ferroelectric nanoparticles, while the small MWNT amounts used prevented the formation of conductive networks. The simple processing method utilized resulted in composites with high real permittivity and low dielectric loss over a wide range of frequency (10 Hz to 1 MHz). The dielectric properties of the polymer matrix nanocomposites with hybrid fillers (BT with and without MWNT) were improved by optimizing the synergistic effects between the charge storage behavior of the ferroelectric phase and the charge transport behavior of the conductive phase. The best combination of real permittivity and dielectric loss properties (71.7 and 0.045 respectively) were obtained for the nanocomposites containing 37.1 vol % of BaTiO 3 and 3 vol % of MWCNT. In addition to achieving reliable dielectric properties, the nanocomposites also displayed flexibility making these composites potentially useful for many flexible electronic devices and electrostatic energy storage devices.

Phenols are very important intermediates in the chemical, pharmaceutical, and materials industries, with more than 7.2 megatons of phenol itself produced per year. [1, 2] Nowadays, about 90 % of the world's phenol demand is satisfied by the Hock process, which involves the peroxidation of cumene, itself obtained from benzene propylation. This industrial process, which is not very efficient in yield (overall 5 %) and energy use, also produces large amounts of acetone and amethylstyrene co-products. Alternative oxidation technologies that avoid production of acetone have been proposed, [2b,c]

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An ideal pair: Various substituted aryl halides react under mild conditions with nitrogen heterocycles in the presence of catalytic amounts of [Fe(acac)3] (acac=acetylacetonate) and copper salts to give the corresponding cross‐coupling products in high yields (see scheme). This cheap and environmentally friendly co‐catalyst system is the first example of cooperative Fe/Cu catalysis in this type of NC bond formation.

Glycoproteins influence a broad spectrum of biological processes including cell-cell interaction, host-pathogen interaction, or protection of proteins against proteolytic degradation. The analysis of their glyco-structures and concentration levels are increasingly important in diagnosis and proteomics. Boronic acids can covalently react with cis-diols in the oligosaccharide chains of glycoproteins to form five- or six-membered cyclic esters. Based on this interaction, boronic acid-based ligands and materials have attracted much attention in both chemistry and biology as the recognition motif for enrichment and chemo/biosensing of glycoproteins in recent years. In this work, we reviewed the progress in the separation, immobilization and detection of glycoproteins with boronic acid-functionalized materials and addressed its application in sensing.

Due to the fascinating structures and wide applications, porous materials with open frameworks have attracted more and more attentions. Herein, a novel two‐dimensional (2D) halogen‐bonded organic framework (XOF–TPPE) was successfully designed and fabricated by iodonium‐bridged N⋅⋅⋅I+⋅⋅⋅N interactions between pyridyl groups and I+ for the first time. The formation of XOF–TPPE and its linear analogue was monitored by 1H NMR, UV–Vis, X‐ray photoelectron spectroscopy (XPS), IR, SEM, TEM, HRTEM and selected‐area electron diffraction (SAED). The structural model of XOF–TPPE was established based on powder X‐ray diffraction (PXRD) data and theoretical simulations. Significantly, synchrotron small‐angle X‐ray scattering (SAXS), DLS and UV–Vis spectroscopy experiments suggested that XOF–TPPE still maintains a stable 2D framework structure in solutions. This research opens up a novel avenue for the development of organic frameworks materials, and may bring new promising applications for the field of porous materials.

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A major constituent in the deposit in Alzheimer's disease (AD) patient brain is the aggregates/ fibrils of amyloid-β (Aβ) peptides containing 39-43 amino acids. The total Aβ levels and the concentration ratio between the most abundant Aβ(1-40) peptide and the more aggregation-prone Aβ(1-42) in body fluids (e.g., cerebrospinal fluid or CSF) have been suggested as possible criteria for early diagnosis of AD. By immobilizing capture antibodies specific to the two peptides in separate fluidic channels, surface plasmon resonance (SPR) has been used to quantify Aβ(1-40) and Aβ(1-42) present in CSF samples collected from AD patients and healthy donors. With signal amplification by streptavidin conjugated to an antibody that is selective to the common Nterminus of the Aβ peptides, concentrations as low as 20 pM can be readily measured. The range of Aβ peptide concentrations measurable by this method spans four orders of magnitude. The ability of regenerating the sensor surface for repeated measurements not only improves the reproducibility, but also enhances the sample throughput. Our data reveal that the ratio of Aβ(1-40) concentration versus Aβ(1-42) concentration in CSF samples from AD patients is almost twice as high as that from healthy persons. In contrast to the commonly used enzyme-linked immunosorbent assay (ELISA), SPR obviates the need of a more expensive and less stable enzyme conjugate and the use of carcinogenic substrate for the signal detection, and allows the binding events to be monitored in real time.