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•A plasmonic Z-scheme catalyst (TiO2/NH2-MIL-125/Au) was designed and constructed.•The Z-scheme architecture endowed TiO2/NH2-MIL-125/Au with stronger redox capability.•The surface ...plasmon resonance of AuNPs improved the charge separation of the catalyst.•A remarkably improved photocurrent density for TiO2/NH2-MIL-125/Au has been achieved.
Developing and nano-engineering of photoanodes with high solar energy utilization and charge separation efficiency is urgently desirable in photoelectrochemical (PEC) water splitting for renewable energy sources. Herein, a novel synergistic coupling catalyst (TiO2/NH2-MIL-125/Au) is constructed by integrating MOFs-based Z-scheme catalysts with the surface plasmon resonance (SPR) of gold nanoparticles (AuNPs). The electron paramagnetic resonance (EPR) spectra and theoretical calculation indicate that the charge transfer path follows the Z-scheme principle and the SPR effect of AuNPs remarkably enhances the electromagnetic (EM) field at the coupling region acting as hot spots. Such superiority in physical structures endows TiO2/ NH2-MIL-125/Au with stronger redox capability and improved charge separation efficiency. Correspondingly, the plasmon coupled Z-scheme catalyst exhibits excellent PEC performance with a 2.2-fold enhancement in comparison with the pristine TiO2 nanotube arrays. This work develops a novel synergistic coupling model by integrating the plasmonic effect with biomimetic Z-scheme systems and sheds light on a deep understanding of plasmon-enhanced Z-scheme catalysts.
Polymers that extend covalently in two dimensions have attracted recent attention
as a means of combining the mechanical strength and in-plane energy conduction of conventional two-dimensional (2D) ...materials
with the low densities, synthetic processability and organic composition of their one-dimensional counterparts. Efforts so far have proven successful in forms that do not allow full realization of these properties, such as polymerization at flat interfaces
or fixation of monomers in immobilized lattices
. Another frequently employed synthetic approach is to introduce microscopic reversibility, at the cost of bond stability, to achieve 2D crystals after extensive error correction
. Here we demonstrate a homogenous 2D irreversible polycondensation that results in a covalently bonded 2D polymeric material that is chemically stable and highly processable. Further processing yields highly oriented, free-standing films that have a 2D elastic modulus and yield strength of 12.7 ± 3.8 gigapascals and 488 ± 57 megapascals, respectively. This synthetic route provides opportunities for 2D materials in applications ranging from composite structures to barrier coating materials.
•A new design of higher performance resonators is introduced, using thermal diodes.•The new design generates single polarity electricity from temperature fluctuation.•A comprehensive literature ...search of thermal diodes is conducted and tabulated.•Design is optimized with numerical simulation, and validated by experiments.•New sources of temperature fluctuations are measured and analysed.
There is a pressing need for durable energy harvesting techniques that are not limited by intermittency, and capable of persistent and continuous operation in a variety of environments.Our laboratory has previously identified ambient thermal fluctuations as potentially abundant, ubiquitous sources of such energy. In this work, we present a mathematical theory for the operation and design of a thermal resonator interfaced with optimized thermal diodes on its external boundaries with the environment. We show that such a configuration is potentially able to produce single polarity temperature difference drastically exceeding that of previously reported thermal resonators by a factor of 5. We further introduce an experimental testbed of mechanical thermal switches capable of mimicking thermal diodes with a possibility to tune thermal rectification in a broad range. The testbed allows us to identify additional design rules for our system dictated by material properties. Lastly, our theory establishes a generic performance metrics over thermal diodes available in the literature. The established framework will help to design novel thermal elements, build efficient thermal harvesting systems, and compose nonlinear thermal circuits.
Abstract
Despite the impressive progress of stimuli‐responsive fluorescent materials, little is known about the influence of confinement created by crystalline polymer over the fluorescence ...properties of fluorescent molecules. The effects of confinement on the fluorescence of an aggregation‐induced emission luminogen (AIEgen) are investigated using computational simulations, which reveal that the confined space induces the AIEgens to take a more planar conformation, resulting in a red‐shifted emission spectrum. With this property, the study is extended to explore the confinement generated by various polymer crystalline forms, and it is shown that different fluorescence colors are activated. This confinement fluorescence effect is attributed to the different spatial dimensions of the polymer amorphous layer between lamellar crystals where the AIEgens are located. These results indicate the immediate association between crystalline structure and fluorescence signals, activating unprecedented photophysical properties of luminescent materials, and also providing the possibility for crystalline structure visualization, it is important for the many polymer crystallization processes occurring in the materials processing.
5-fluorouracil (5-FU) is basically used in the field of postoperative chemotherapy of gastric cancer (GC), the goal of this study was to evaluate improvement of long-term survival rate among GC ...patients after the 5-FU implants treatment.
The study included 145 patients with gastric cancer who received postoperative chemotherapy with 5-FU implants and had complete follow-up information. According to the sex, age and clinical stage of 5-FU implants group, 74 patients were matched as the control group at the same time. In the study, we compared the 5-year overall survival rate with progression-free survival rate in the two groups, and the drug safety for both groups during the treatment was also compared.
The median follow-up time was 85 months (range 60-116 months). 31 patients (21.38%) died of tumor recurrence in 5-FU implants group and 21 (28.38%) in control group. In the control group, metastatic lesions were found in the small intestine, left adrenal gland and peritoneum in three patients. The 5-year progression-free survival (PFS) rate was 79.71% in 5-FU group and 67.12% in control (
= 0.0045). The 5-year overall survival (OS) rate was 77.68% in 5-FU implants group and 64.87% in control (
= 0.0159). Both the 5-years OS and PFS rates in 5-FU group were better than control group without significant side effect.
5-FU implants may improve 5-years OS and PFS rates after surgery in gastric cancer patients, while good safety profile suggests it could be reliable.
Photon-electron interactions are essential for many areas such as energy conversion, signal processing, and emerging quantum science. However, the current demonstrations are typically targeted to ...fiber and on-chip applications and lack of study in wave space. Here, we introduce a concept of optoelectronic metasurface that is capable of realizing direct and efficient optical–microwave interactions in free space. The optoelectronic metasurface is realized via a hybrid integration of microwave resonant meta-structures with a photoresponsive material. As a proof of concept, we construct an ultrathin optoelectronic metasurface using photodiodes that is bias free, which is modeled and analyzed theoretically by using the light-driven electronic excitation principle and microwave network theory. The incident laser and microwave from the free space will interact with the photodiode-based metasurface simultaneously and generate strong laser–microwave coupling, where the phase of output microwave depends on the input laser intensity. We experimentally verify that the reflected microwave phase of the optoelectronic metasurface decreases as the incident laser power becomes large, providing a distinct strategy to control the vector fields by the power intensity. Our results offer fundamentally new understanding of the metasurface capabilities and the wave–matter interactions in hybrid materials.
The recently discovered neutron star transient Swift J0243.6+6124 has been monitored by the Hard X-ray Modulation Telescope. Based on the obtained data, we investigate the broadband spectrum of the ...source throughout the outburst. We estimate the broadband flux of the source and search for possible cyclotron line in the broadband spectrum. However, no evidence of line-like features is found up to 150 keV. In the absence of any cyclotron line in its energy spectrum, we estimate the magnetic field of the source based on the observed spin evolution of the neutron star by applying two accretion torque models. In both cases, we get consistent results with B ∼ 1013 G, D ∼ 6 kpc and peak luminosity of >1039 erg s−1, which makes the source the first Galactic ultraluminous X-ray source hosting a neutron star.
Automatic emotion recognition plays a key role in human-computer interactions. Multimodal emotion recognition has attracted much attention in recent years. When multimodalities are used, different ...modalities interact with each other and the obtained results tend to be accurate in general. However, there are also cases of unimodal anomalies. Most of the existing studies do not take into account the existence of outliers in the multimodality, which leads to low accuracy of the prediction results. This paper proposes fuzzy weighted support vector machine for regression (FWSVR) to deal with outliers and prediction errors. We design an automatic affective recognition model structure to analyze continuous dimension emotions based on multimodality (audio and visual). The LIRIS-ACCEDE database is used in this work. Experimental results indicate that the concordance correlation coefficient (CCC) is 0.9456 for arousal and 0.9183 for valence on the test set. The fusion result obtained when using fuzzy weighting is much better than the direct fusion one.
In a propeller blade optimization, both aerodynamic and aeroacoustic performance were considered simultaneously. A multi-fidelity sampling scheme was adopted by Transfer Learning (TL) to improve the ...overall optimization efficiency. A Deep Neural Network (DNN) was selected to map the non-linear relationship between the blade parameters and the aerodynamic/aeroacoustic performance, with the optimization being achieved by implementing a deep reinforcement learning algorithm, namely, Deep Deterministic Policy Gradient (DDPG), upon which a Multi-fidelity DNN based surrogate model (TL-MFDNN) was introduced with Transfer Learning between pre-trained and retrained processes. It was found that, by comparing the TL-MFDNN surrogate model based optimization with DDPG optimization using direct CFD simulation, the overall computing cost can be saved up to 77.3% and the optimized propeller has maximum noise reduction of up to 1.69 dB, with a negligible penalty on propulsive performance.
Long-chain alkyl diols (LCDs) can be used as organic geochemical proxies for paleoceanographic change, especially in marginal sea areas where large volumes of sediments are deposited rapidly and ...continuously. However, little is known about the applicability and response on a millennium scale in relation with existing records in those sediments. We reconstruct changes in upwelling and terrestrial organic matter (OM) input in core sediments from the Zhejiang Fujian coastal station (T08) and Yangtze River Estuary station (T06) in the inner shelf of the East China Sea (ECS) over the last millennium, using the LCD based proxies: diol index 2 (DI-2), and FC
32
1,15-diol. Our results show that DI-2 values ((C
28
+C
30
)1,14-diols/((C
28
+C
30
)1,13-diols+(C
28
+C
30
)1,14-diols)) at T08 decrease significantly during 600–400 yr BP but increase gradually after 400 yr BP. The FC
32
1,15-diol proxy (C
32
1,15-diol×100/((C
28
+C
30
)1,13-diols+(C
30
+C
32
)1,15-diols)) at T06 shows marked fluctuations during 1000–800 yr BP, followed by a significant decline during 800–500 yr BP but a subsequent increase from 500 to 300 yr BP. We find that variations in DI-2 values are broadly consistent with changes in the strength of the East Asian Summer Monsoon (EASM) and the Kuroshio Current and are likely linked to changes in the frequency and intensity of the El Niño-Southern Oscillation (ENSO). The increased strength of the EASM causes greater offshore movement of the upper layer of seawater, which in turn triggers upwelling of bottom waters formed by Kuroshio subsurface waters. We find that variations in FC
32
1,15-diol proxy are controlled mainly by the East Asian Winter Monsoon (EAWM) and the Yangtze River discharge. By increasing the strength of the EAWM, southward transportation of material deposited in the estuary of the Yangtze River by the ECS coastal currents is promoted. In addition, we synthesize records of other organic geochemical indicators nearby core sediments in the ECS; these records emphasize the importance of reconstructing the evolutionary history of upwelling and subdividing the relative inputs of terrestrial OM. Our study provides a new means for reconstructing the evolution of upwelling and terrestrial OM input in the inner shelf of the ECS over the last millennium.
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