Porous carbons are widely used in the energy storage and conversion field because of their excellent electrical conductivity, high specific surface area and superb electrochemical stability. The ...template method is one of the most advanced approaches to prepare porous carbons with well-defined pore structures and suitable pore size distributions. The pore formation mechanism and structure-property relationships of porous carbons obtained by template methods for supercapacitor electrodes are summarized. They include hard templates (magnesium-based, silica-based, zinc-based, calcium-based templates), soft templates (conventional soft template, ionic liquids, deep eutectic solvent) and self-templates (biomass, MOFs). Furthermore, the problems in tailoring the pore texture of porous carbons are clarified, and proposals are made for future research.
Uranium is a key element in the nuclear industry and also a global environmental contaminant with combined highly toxic and radioactive. Currently, the materials based on post-modification of ...amidoxime have been developed for uranium detection and adsorption. However, the affinity of amidoxime group for vanadium is stronger than that of uranium, which is the main challenge hindering the practical application of amidoxime-based adsorbents. Herein, we synthesized a fluorescent covalent organic framework (TFPPy-BDOH) through integrating biphenyl diamine and pyrene unit into the π-conjugated framework. TFPPy-BDOH has an excellent selectivity to uranium due to the synergistic effect of nitrogen atom in the imine bond and hydroxyl groups in conjugated framework. It can achieve ultra-fast fluorescence response time (2 s) and ultra-low detection limit (8.8 nM), which may be attributed to its intrinsic regular porous channel structures and excellent hydrophilicity. More excitingly, TFPPy-BDOH can chemically reduce soluble U (VI) to insoluble U (IV), and release the binding site to adsorb additional U (VI), achieving high adsorption capacity of 982.6 ± 49.1 mg g−1. Therefore, TFPPy-BDOH can overcome the challenges faced by current amidoxime-based adsorbents, making it as a potential adsorbent in practical applications.
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•A fluorescent COF (TFPPy-BDOH) is synthesized by a one-step method.•TFPPy-BDOH has ultra-fast fluorescence response time for UO22+.•TFPPy-BDOH can selectively chemically reduce soluble U(VI) to insoluble U(IV).•TFPPy-BDOH achieves high sensitivity and selectivity for detecting and capturing UO22+ in harsh environments.
We report the first example of vinylene-linked covalent organic framework (Tp-TMT) with enhanced uranium adsorption through combined selective ligand binding, chemical reduction and photocatalytic ...reduction. The dense hydroxyl functional groups on the Tp-TMT framework had good selectivity and excellent chemical reduction performance for U(VI). Meanwhile, the synergistic effect of hydroxyl groups and triazine unit significantly enhanced the photocatalytic reduction activity. Thus Tp-TMT exhibited incredible adsorption kinetics and capacity for uranium.
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•COFs effectively capture uranium through three coordinated mechanisms.•Tp-TMT has excellent visible light conversion efficiency and low band gap.•Tp-TMT enhances uranium adsorption through selective ligand binding and reduction.•Tp-TMT exhibits incredible adsorption kinetics and capacity for uranium.
So far, it remains a challenge to synthesize uranium adsorbents with robust stability, high adsorption capacity, excellent photocatalytic activity and easy regeneration. Herein, we report the first example of vinylene-linked covalent organic framework (Tp-TMT) with enhanced uranium adsorption through combined selective ligand binding, chemical reduction and photocatalytic reduction. The unique structure and excellent photocatalytic activity of Tp-TMT make it very suitable for photo-enhanced uranium adsorption through three synergistic mechanisms, thus exhibiting an outstanding uranium adsorption capacity (2362.4 mg g−1). In the dark, a large number of hydroxyl groups in the Tp-TMT framework serve as selective binding sites for uranium, and reduce part of U(VI) to U(IV), thereby greatly improving the adsorption capacity. Meanwhile, the synergistic effect of the triazine units and hydroxyl groups in the highly conjugated framework greatly decreases the optical band gap of Tp-TMT, and an additional U(VI) photocatalytic reduction process can occur under light irradiation, further increasing the adsorption kinetics and capacity. This work explored the structural and functional design of covalent organic frameworks for the adsorption and reduction of uranium in nuclear industry wastewater.
•BC pyrolyzed at 600°C significantly boosted H2 production from PSCB.•BC implemented selective enrichment and colonization of functional bacteria.•BC stimulated synergistic effect and activated EET ...between functional bacteria.•New insight in understanding improved AD performance by BC was proposed.
The influence of biochar (BC) on anerobic digestion (AD) of organic wastes have been widely studied. However, the effect of BC on rate-limiting step during AD of lignocellulosic waste, i.e. the hydrolysis and acidogenesis step, is rarely studied and the underlying mechanisms have not been investigated. In this study, the benefits of BC with respect to dark fermentative hydrogen production were explored in a fermentation system by a heat-shocked consortium from sewage sludge (SS) with pretreated sugarcane bagasse (PSCB) as carbon source. The results showed that biochar boosted biohydrogen production by 317.1% through stimulating bacterial growth, improving critical enzymatic activities, manipulating the ratio of NADH/NAD+ and enhancing electron transfer efficiency of fermentation system. Furthermore, cellulolytic Lachnospiraceae was efficiently enriched and electroactive bacteria were selectively colonized and the ecological niche was formed on the surface of biochar. Synergistic effect between functional bacteria and extracellular electron transfer (EET) in electroactive bacteria were assumed to be established and maintained by biochar amendment. This study shed light on the underlying mechanisms of improved performance of biohydrogen production from lignocellulosic waste during mesophilic dark fermentation by BC supplementation.
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With this expected future advance of HVDC, the use of gas insulated transmission lines (GIL) for dc application are getting increasingly interesting. For now, the problem of surface charge ...accumulation on gas-insulator interface is one of the critical factors for the development of DC-GIL. In many previous works, the model of surface charge accumulation on insulator was investigated. However, the quantitative relationship between temperature and surface charge accumulation on insulator was not exactly obtained since the lack of complicated heat transfer progress in the model. In this paper, the heat transfer surface charge accumulation model of operating DC-GIL was developed, including the nonlinear relationship between volume current in gas and electric field. Moreover, the space charge was also considered in the model. Based on the developed model, temperature distributions in DC-GIL insulator under different current are obtained. Afterwards, the temperature impact on space charge density in the insulator, the saturation time of surface charge accumulation, the surface charge on the insulator surface, and the electric field distribution on the insulator were investigated. It was proven that the tangential component of the electric field reaches to 5.3 kV/mm on lower interface and 5.0 kV/mm on upper interface for Ti=378 K. This value increase 17.8% on lower interface and 17.6% on upper interface along with the conductor temperature from 298 K to 378 K. The data can be referred in the insulation design of DC-GIL.
T-helper type 17 cells (T(H)17) are implicated in rodent models of immune-mediated diseases. Here we report their involvement in human uveitis and scleritis, and validate our findings in experimental ...autoimmune uveoretinitis (EAU), a model of uveitis. T(H)17 cells were present in human peripheral blood mononuclear cells (PBMC), and were expanded by interleukin (IL)-2 and inhibited by interferon (IFN)-gamma. Their numbers increased during active uveitis and scleritis and decreased following treatment. IL-17 was elevated in EAU and upregulated tumor necrosis factor (TNF)-alpha in retinal cells, suggesting a mechanism by which T(H)17 may contribute to ocular pathology. Furthermore, IL-27 was constitutively expressed in retinal ganglion and photoreceptor cells, was upregulated by IFN-gamma and inhibited proliferation of T(H)17. These findings suggest that T(H)1 cells may mitigate uveitis by antagonizing the T(H)17 phenotype through the IFN-gamma-mediated induction of IL-27 in target tissue. The finding that IL-2 promotes T(H)17 expansion provides explanations for the efficacy of IL-2R antibody therapy in uveitis, and suggests that antagonism of T(H)17 by IFN-gamma and/or IL-27 could be used for the treatment of chronic inflammation.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Galloping of overhead transmission lines (OHTLs) may induce conductor breakage and tower collapse, and there is no effective method for long distance distribution on-line galloping monitoring. To ...overcome the drawbacks of the conventional galloping monitoring systems, such as sensitivity to electromagnetic interference, the need for onsite power, and short lifetimes, a novel optical remote passive measuring system is proposed in the paper. Firstly, to solve the hysteresis and eccentric load problem in tension sensing, and to extent the dynamic response range, an 'S' type elastic element structure with flanges was proposed. Then, a tension experiment was carried out to demonstrate the dynamic response characteristics. Moreover, the designed tension sensor was stretched continuously for 30 min to observe its long time stability. Last but not the least, the sensor was mounted on a 70 m conductor model, and the conductor was oscillated at different frequencies to investigate the dynamic performance of the sensor. The experimental results demonstrate the sensor is suitable for the OHTL galloping detection. Compared with the conventional sensors for OHTL monitoring, the system has many advantages, such as easy installation, no flashover risk, distribution monitoring, better bandwidth, improved accuracy and higher reliability.
Herein, a novel fluorescent ionic covalent organic framework (BTTA–BDNP) based on a linked carbazole unit was constructed for the synchronous monitoring and capture of TcO4−/ReO4−. BTTA–BDNP has a ...fast fluorescence response time with a low detection limit (66.7 nM) for ReO4− (a non-radioactive substitute for TcO4−). Meanwhile, the high charge density and hydrophobic skeleton of BTTA–BDNP enable it to exhibit rapid and selective trapping of ReO4− in complex environments.
Protein analysis under biological conditions is now regarded as indispensable for understanding the structure and function of proteins, in addition to in vitro studies using purified target proteins. ...Because there are many molecules other than the protein-of-interest (POI) under live cell conditions, selective labeling of a POI is critical to distinguish the POI from other proteins for precise analysis. Protein labeling strategies utilizing genetically encoded tags have been used in POI modification in the complex environment of live cells. However, genetic manipulation may often induce overexpression of the POI and/or perturb the cellular context, resulting in unexpected artifacts in the protein analysis. Alternatively, recent progress in chemical biology has produced two major chemical approaches for analyzing endogenous proteins under native conditions. In this review, we summarize these techniques that utilize either protein-selective chemical labeling or proteome-directed chemical modification.
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Protein analysis in a biologically relevant context is now regarded as indispensable for deciphering the genuine structure and function of proteins. In this review, Shiraiwa et al. summarize recent advances in chemical approaches utilizing protein-selective chemical labeling and proteome-directed chemical modification.
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