263 research outputs found
Cross-linked CoMoO4/rGO nanosheets as oxygen reduction catalyst
Development of inexpensive and robust electrocatalysts towards oxygen reduction reaction
(ORR) is crucial for the cost-affordable manufacturing of metal-air batteries and fuel cells. Here
we show that cross-linked CoMoO4 nanosheets and reduced graphene oxide (CoMoO4/rGO) can
be integrated in a hybrid material under one-pot hydrothermal conditions, yielding a composite
material with promising catalytic activity for oxygen reduction reaction (ORR). Cyclic voltammetry
(CV) and linear sweep voltammetry (LSV) were used to investigate the efficiency of the fabricated
CoMoO4/rGO catalyst towards ORR in alkaline conditions. The CoMoO4/rGO composite revealed
the main reduction peak and onset potential centered at 0.78 and 0.89 V (vs. RHE), respectively.
This study shows that the CoMoO4/rGO composite is a highly promising catalyst for the ORR under
alkaline conditions, and potential noble metal replacement cathode in fuel cells and metal-air batteries
Exploring structural complexity in the discovery and self-assembly of a family of nanoscale chalcoxides from {Se8Mo36} to {Se26Mo68}
Herein, we show the controlled generation of multi-component libraries based on the [MoV2S2O2]2+/MoVIO42−/SeIVO32−/C4O42− system leading to the formation of a whole new family of nanosized molecular chalcoxides, {Se8Mo36} 1, {Se8Mo40} 2, {Se8Mo56} 3, {Se20Mo56} 4 and {Se26Mo68} 5, of the general formula {(MoV2O2S2)a(OH)b(SeIVO3)c(C4O4)d(MoVI2O7)e}n−, where a, b, c, d, e, n = [16, 20, 8, 6, 2, 20] for 1, [18, 24, 8, 6, 2, 20] for 2, [24, 32, 8, 8, 4, 24] for 3, [28, 32, 20, 8, 0, 32] for 4 and [34, 36, 26, 8, 0, 36] for 5. The coordination modulation effect offered by the SeIVO32− and the C4O42− anions lead to the generation of new building blocks, [(MoV2O2S2)3(OH)6(C4O4) (MoVI2O7)]4−, and the discovery of a new family of clusters of increasing nuclearity and complexity
Processing Multi-Constituent Units: Preview Effects During Reading of Chinese Words, Idioms and Phrases
Arguably, the most contentious debate in the field of eye movement control in reading has centred on whether words are lexically processed serially or in parallel during reading. Chinese is character-based and unspaced, meaning the issue of how lexical processing is operationalized across potentially ambiguous, multi-character strings is not straightforward. We investigated Chinese readers’ processing of frequently occurring Multi-Constituent Units (MCUs), that is, linguistic units comprised of more than a single word, that might be represented lexically as a single representation. In Experiment 1, we manipulated the linguistic category of a two-constituent Chinese string (word, MCU, or phrase), and the preview of its second constituent (identical or pseudocharacter) using the boundary paradigm (Rayner, 1975) with the boundary located before the two-constituent string. A robust preview effect was obtained when the second constituent alongside the first formed a word or MCU, but not a phrase, suggesting that frequently occurring MCUs are lexicalized and processed parafoveally as single units during reading. In Experiment 2, we further manipulated phrase type of a two-constituent but three-character Chinese string (idiom with a 1-character modifier and a 2-character noun, or matched phrase) and preview of the second constituent noun (identity or pseudocharacter). A greater preview effect was obtained for idioms than phrases indicating that idioms are processed to a greater extent in the parafovea than matched phrases. Together, the results of these two experiments suggest that lexical identification processes in Chinese can be operationalized over linguistic units that are larger than an individual word
Measurements of the Mass and Full-Width of the Meson
In a sample of 58 million events collected with the BES II detector,
the process J/ is observed in five different decay
channels: , , (with ), (with
) and . From a combined fit of all five
channels, we determine the mass and full-width of to be
MeV/ and
MeV/.Comment: 9 pages, 2 figures and 4 table. Submitted to Phys. Lett.
Aggregation-Induced Emission (AIE), Life and Health
Light has profoundly impacted modern medicine and healthcare, with numerous luminescent agents and imaging techniques currently being used to assess health and treat diseases. As an emerging concept in luminescence, aggregation-induced emission (AIE) has shown great potential in biological applications due to its advantages in terms of brightness, biocompatibility, photostability, and positive correlation with concentration. This review provides a comprehensive summary of AIE luminogens applied in imaging of biological structure and dynamic physiological processes, disease diagnosis and treatment, and detection and monitoring of specific analytes, followed by representative works. Discussions on critical issues and perspectives on future directions are also included. This review aims to stimulate the interest of researchers from different fields, including chemistry, biology, materials science, medicine, etc., thus promoting the development of AIE in the fields of life and health
Observation of a near-threshold enhancement in th p pbar mass spectrum from radiative J/psi-->gamma p pbar decays
We observe a narrow enhancement near 2mp in the invariant mass spectrum of
ppbar pairs from radiative J/psi-->gamma ppbar decays. The enhancement can be
fit with either an S- or P-wave Breit Wigner fuction. In the case of the S-wave
fit, the peak mass is below the 2mp threshold and the full width is less than
30 MeV. These mass and width values are not consistent with the properties of
any known meson resonance.Comment: 5 pages, 4 figures, submitted to Phys. Rev. Let
Evidence of psi(3770) non-DD-bar Decay to J/psi pi+pi-
Evidence of decays to a non- final state is
observed. A total of \psi(3770) \to \PPJP events are
obtained from a data sample of 27.7 taken at center-of-mass
energies around 3.773 GeV using the BES-II detector at the BEPC. The branching
fraction is determined to be BF(\psi(3770) \to \PPJP)=(0.34\pm 0.14 \pm
0.09)%, corresponding to the partial width of \Gamma(\psi(3770) \to \PPJP) =
(80 \pm 33 \pm 23) keV.Comment: 8 pages, 7 figures, Submitted to Physics Letters
The Physics of the B Factories
This work is on the Physics of the B Factories. Part A of this book contains a brief description of the SLAC and KEK B Factories as well as their detectors, BaBar and Belle, and data taking related issues. Part B discusses tools and methods used by the experiments in order to obtain results. The results themselves can be found in Part C