45 research outputs found
Transparent Wood Film Incorporating Carbon Dots as Encapsulating Material for White Light-Emitting Diodes
Epoxy
resins are the main encapsulation materials for light-emitting
diodes (LEDs) due to their high transparency, appropriate mechanical
strength, and excellent thermal stability. However, environmentally
benign materials needed to be developed with improving performances.
Transparent wood and its nanocomposites prepared from natural biomass
are potential alternative materials to them. Green preparation of
transparent wood incorporating with trichromatic systems is an attractive
topic, especially for white LEDs (W-LEDs). Here, multiple-color-emission
carbon dots (CDs), serving as trichromatic systems in W-LEDs, were
synthesized by tuning the extent of graphitization and surface function
of the nanoparticles using citric acid and urea as feedstocks. Then,
a green, facile, and energy-efficient method for the preparation of
carbon dots/transparent wood (CDs-TW) composites was raised by the
ultrafast removing of lignin from wood using deep eutectic solvent
(DES, oxalic acid and choline chloride) under microwave-assisted treatment,
and then, CDs and polyÂ(acrylic acid) (PAA) were filled into the delignified
wood through an in situ polymerization. The transparent wood film
embedding multicolor CDs was fabricated, which showed white light
emission under ultraviolet light excitation and enhanced mechanical
tensile strength (60.92 MPa). Simultaneously, the as-prepared film
can be used as an encapsulation film for white LEDs, which exhibited
excellent color characteristics with the Commission Internationale
Eclairage (CIE) color coordinates, a correlated color temperature
(CCT), and a color rendering index (CRI) of (0.33, 0.32), 5237 K,
and 83, respectively. This provides a simple route to prepare metal-free
wood-based encapsulating materials for W-LEDs
Smoothing Surface Trapping States in 3D Coral-Like CoOOH-Wrapped-BiVO<sub>4</sub> for Efficient Photoelectrochemical Water Oxidation
Highly efficient
oxygen evolution driven by abundant sunlight is a key to realize overall
water splitting for large-scale conversion of renewable energy. Here,
we report a strategy for the interfacial atomic and electronic coupling
of layered CoOOH and BiVO<sub>4</sub> to deactivate the surface trapping
states and suppress the charge-carrier recombination for high photoelectrochemical
(PEC) water oxidation activity. The successful synthesis of a 3D ultrathin-CoOOH-overlayer-coated
coral-like BiVO<sub>4</sub> photoanode effectively tailors the migration
route of photocarriers on the semiconductor/liquid interface to realize
a great increase of ∼200% in the photovoltage relative to bare
BiVO<sub>4</sub>, consequently decreasing the corresponding onset
potential of PEC water splitting from 0.60 to 0.20 V<sub>RHE</sub>. As a result, the unique CoOOH/BiVO<sub>4</sub> photoanode could
efficiently perform PEC water oxidation in a neutral aqueous solution
(pH = 7) with a high photocurrent density of 4.0 mA/cm<sup>2</sup> at 1.23 V<sub>RHE</sub> and a prominent quantum efficiency of 65%
at 450 nm. Electronic structural characterizations and theoretical
calculations reveal that the combination of layered CoOOH and BiVO<sub>4</sub> forming interfacial oxo-bridge bonding could greatly eliminate
surface trapping states and promote the direct transfer of photogenerated
holes from the valence band to the surface water redox potential for
water oxidation
Meta-analysis of the <i>IL10</i> −1082G/A polymorphism and SLE.
<p>OR: odds ratio; CI: confidence interval; SLE: systemic lupus erythematosus.</p>*<p>exclude the studies deviating from Hardy-Weinberg equilibrium.</p>#<p>exclude the study by Shen (2003).</p
Taming Dinitramide Anions within an Energetic Metal–Organic Framework: A New Strategy for Synthesis and Tunable Properties of High Energy Materials
Energetic polynitro anions, such
as dinitramide ion [NÂ(NO<sub>2</sub>)<sub>2</sub><sup>–</sup>], have attracted significant interest
in the field of energetic materials due to their high densities and
rich oxygen contents; however, most of them usually suffer from low
stability. Conveniently stabilizing energetic polynitro anions to
develop new high energy materials as well as tuning their energetic
properties still represent significant challenges. To address these
challenges, we herein propose a novel strategy that energetic polynitro
anions are encapsulated within energetic cationic metal–organic
frameworks (MOFs). We present NÂ(NO<sub>2</sub>)<sub>2</sub><sup>–</sup> encapsulated within a three-dimensional (3D) energetic cationic
MOF through simple anion exchange. The resultant inclusion complex
exhibits a remarkable thermal stability with the onset decomposition
temperature of 221 °C, which is, to our knowledge, the highest
value known for all dinitramide-based compounds. In addition, it possesses
good energetic properties, which can be conveniently tuned by changing
the mole ratio of the starting materials. The encapsulated anion can
also be released in a controlled fashion without disrupting the framework.
This work may shed new insights into the stabilization, storage, and
release of labile energetic anions under ambient conditions, while
providing a simple and convenient approach for the preparation of
new energetic MOFs and the modulation of their energetic properties
Meta-analysis of the IL-10.G and IL-10.R microsatellites with SLE.
<p>OR: odds ratio; CI: confidence interval; SLE: systemic lupus erythematosus.</p
Regions of decreased grey matter volume at baseline in antipsychotic-naïve patients with schizophrenia compared to healthy controls. <i>P</i><0.001, uncorrected, threshold = 50.
<p>Regions of decreased grey matter volume at baseline in antipsychotic-naïve patients with schizophrenia compared to healthy controls. <i>P</i><0.001, uncorrected, threshold = 50.</p
Flow diagram of the study selection process.
<p>Flow diagram of the study selection process.</p
Characteristics of included studies in this meta-analysis.
<p>ASO: allele-specific oligonucleotid hybridization; RFLP: restriction fragment length polymorphism; PCR-SSP: polymerase chain reaction sequence specific primer; HPLC: high-performance liquid chromatography; MS: mass spectrometry; PLACE-SSCP post-PCR fluorescent labeling and automated capillary electrophoresis under single-strand conformation polymorphism conditions; SNPs: single nucleotide polymorphisms.</p>#<p>no polymorphisms.</p
Activating Cobalt Nanoparticles via the Mott–Schottky Effect in Nitrogen-Rich Carbon Shells for Base-Free Aerobic Oxidation of Alcohols to Esters
Heterogeneous
catalysts of inexpensive and reusable transition-metal
are attractive alternatives to homogeneous catalysts; the relatively
low activity of transition-metal nanoparticles has become the main
hurdle for their practical applications. Here, the <i>de novo</i> design of a Mott–Schottky-type heterogeneous catalyst is
reported to boost the activity of a transition-metal nanocatalyst
through electron transfer at the metal/nitrogen-doped carbon interface.
The Mott–Schottky catalyst of nitrogen-rich carbon-coated cobalt
nanoparticles (Co@NC) was prepared through direct polycondensation
of simple organic molecules and inorganic metal salts in the presence
of g-C<sub>3</sub>N<sub>4</sub> powder. The Co@NC with controllable
nitrogen content and thus tunable Fermi energy and catalytic activity
exhibited a high turnover frequency (TOF) value (8.12 mol methyl benzoate
mol<sup>–1</sup> Co h<sup>–1</sup>) for the direct,
base-free, aerobic oxidation of benzyl alcohols to methyl benzoate;
this TOF is 30-fold higher than those of the state-of-the-art transition-metal-based
nanocatalysts reported in the literature. The presented efficient
Mott–Schottky catalyst can trigger the synthesis of a series
of alkyl esters and even diesters in high yields
Regions of increased grey matter volume from baseline to follow-up in patients with schizophrenia.
<p>Regions of increased grey matter volume from baseline to follow-up in patients with schizophrenia.</p