The creation of efficient artificial systems that mimic natural photosynthesis represents a key current challenge. Here, we describe a high-performance recyclable photocatalytic core-shell nanofibre ...system that integrates a cobalt catalyst and a photosensitizer in close proximity for hydrogen production from water using visible light. The composition, microstructure and dimensions-and thereby the catalytic activity-of the nanofibres were controlled through living crystallization-driven self-assembly. In this seeded growth strategy, block copolymers with crystallizable core-forming blocks and functional coronal segments were coassembled into low-dispersity, one-dimensional architectures. Under optimized conditions, the nanofibres promote the photocatalytic production of hydrogen from water with an overall quantum yield for solar energy conversion to hydrogen gas of ~4.0% (with a turnover number of >7,000 over 5 h, a frequency of >1,400 h
and a H
production rate of >0.327 μmol h
with 1.34 μg of catalytic polymer (that is, >244,300 μmol h
g
of catalytic polymer)).
Battery electric vehicles (BEVs) have emerged as a promising alternative to traditional internal combustion engine (ICE) vehicles due to benefits in improved fuel economy, lower operating cost, and ...reduced emission. BEVs use electric motors rather than fossil fuels for propulsion and typically store electric energy in lithium-ion cells. With rising concerns over fossil fuel depletion and the impact of ICE vehicles on the climate, electric mobility is widely considered as the future of sustainable transportation. BEVs promise to drastically reduce greenhouse gas emissions as a result of the transportation sector. However, mass adoption of BEVs faces major barriers due to consumer worries over several important battery-related issues, such as limited range, long charging time, lack of charging stations, and high initial cost. Existing solutions to overcome these barriers, such as building more charging stations, increasing battery capacity, and stationary vehicle-to-vehicle (V2V) charging, often suffer from prohibitive investment costs, incompatibility to existing BEVs, or long travel delays. In this paper, we propose Peer-to-Peer Car Charging (P2C2), a scalable approach for charging BEVs that alleviates the need for elaborate charging infrastructure. The central idea is to enable BEVs to share charge among each other while in motion through coordination with a cloud-based control system. To re-vitalize a BEV fleet, which is continuously in motion, we introduce Mobile Charging Stations (MoCS), which are high-battery-capacity vehicles used to replenish the overall charge in a vehicle network. Unlike existing V2V charging solutions, the charge sharing in P2C2 takes place while the BEVs are in-motion, which aims at minimizing travel time loss. To reduce BEV-to-BEV contact time without increasing manufacturing costs, we propose to use multiple batteries of varying sizes and charge transfer rates. The faster but smaller batteries are used for charge transfer between vehicles, while the slower but larger ones are used for prolonged charge storage. We have designed the overall P2C2 framework and formalized the decision-making process of the cloud-based control system. We have evaluated the effectiveness of P2C2 using a well-characterized simulation platform and observed dramatic improvement in BEV mobility. Additionally, through statistical analysis, we show that a significant reduction in carbon emission is also possible if MoCS can be powered by renewable energy sources.
Photochemical reactions at lower energy than the absorption window are currently achieved by multi-photon processes, including two-photon absorption and photon upconversion, which have limited energy ...utilization efficiency. Here, we report a one-photon strategy based on triplet–triplet energy transfer (TTET) between a photosensitizer and a photocleavable molecule to achieve photolysis at low energy. To verify this concept, we chose platinum(II) tetraphenyltetrabenzoporphyrin (PtTPBP) as the photosensitizer and synthesized a boron-dipyrromethene (BODIPY)-based prodrug as the photocleavable molecule. Photolysis of the prodrug is achieved by TTET upon excitation of PtTPBP at 625 nm with a photolysis quantum yield of 2.8%. Another demonstration shows an unexpected higher photolysis quantum yield than the direct excitation at 530 nm. This strategy opens a new path for achieving photolysis at long wavelengths, benefiting the applications in biological studies, photopharmacology, and photoresponsive drug delivery.
Objectives Preeclampsia/eclampsia (PE), a critical complication during pregnancy, has been suggested to correlate with immune cell phenotypes and levels of circulating inflammatory proteins. Our ...study aimed to employ a two-sample mendelian randomization (MR) analysis to assess the potential causal effects of immune cell phenotypes and circulating inflammatory proteins on the onset of PE. Methods We utilized summary-level data from genome-wide association studies (GWAS). This included statistics for 371 immune cell phenotypes from 3,757 individuals in the Sardinian founder population, and data on 91 circulating inflammatory proteins from 14,824 European ancestry participants. Additionally, genetic associations related to PE were extracted from the FinnGen consortium, involving 1,413 cases and 287,137 controls. We applied inverse variance weighting (IVW) and supplementary methods like MR-Egger, weighted median, and weighted mode to comprehensively assess potential causal links. Results Our analysis revealed significant causal associations of several immune cells type and inflammatory proteins with PE. Out of the immune cell phenotypes analyzed, six immune phenotypes emerged as significant risk factors ( p < 0.01), mainly include CD4 on activated and secreting CD4 regulatory T cells, CD28 on CD39+ CD4+ T cells, CD127- CD8+ T cell absolute cell (AC) counts, HLA DR on HLA DR+ CD8+ T cell, CD66b on CD66b++ myeloid cells, and HLA DR on dendritic cells. And ten were identified as protective factors ( p < 0.01). Such as CD45 on CD33br HLA DR+ CD14-, CD33+ HLA DR+ AC, CD33+ HLA DR+ CD14- AC, CD33+ HLA DR+ CD14dim AC, CD27 on CD24+ CD27+ B cell, CD20- CD38- %B cell, IgD- CD24- %B cell CD80 on plasmacytoid DC, CD25 on CD4+ T cell, and CD25 on activated & secreting CD4 regulatory T cell. Furthermore, among the inflammatory proteins studied, five showed a significant association with PE, with three offering protective effects mainly include that C-X-C motif chemokine 1, tumor necrosis factor ligand superfamily member 14, and C-C motif chemokine 19 and two exacerbating PE risk such as STAM-binding domain and Interleukin-6 (p <0.05). Conclusions Our study highlights the pivotal roles played by diverse immune cell phenotypes and circulating inflammatory proteins in the pathophysiology of PE. These findings illuminate the underlying genetic mechanisms, emphasizing the criticality of immune regulation during pregnancy. Such insights could pave the way for novel intervention strategies in managing PE, potentially enhancing maternal and neonatal health outcomes.
Pathogen infections and cancer are two major human health problems. Herein, we report the synthesis of an organic salt photosensitizer (PS), called 4TPA‐BQ, by a one‐step reaction. 4TPA‐BQ presents ...aggregation‐induced emission features. Owing to the aggregation‐induced reactive oxygen species generated and a sufficiently small ΔEST, 4TPA‐BQ shows a satisfactorily high 1O2 generation efficiency of 97.8 %. In vitro and in vivo experiments confirmed that 4TPA‐BQ exhibited potent photodynamic antibacterial performance against ampicillin‐resistant Escherichia coli with good biocompatibility in a short time (15 minutes). When the incubation duration persisted long enough (12 hours), cancer cells were ablated efficiently, leaving normal cells essentially unaffected. This is the first reported time‐dependent fluorescence‐guided photodynamic therapy in one individual PS, which achieves ordered and multiple targeting simply by varying the external conditions. 4TPA‐BQ reveals new design principles for the implementation of efficient PSs in clinical applications.
Millennium bug: A simple and highly efficient photosensitizer, called 4TPA‐BQ, operates by aggregation‐induced emission. A broad‐spectrum and potent antibacterial activity was attained after incubating 4TPA‐BQ with pathogens for 15 minutes. Upon lengthening of the incubation time to 12 hours, photodynamic therapy with 4TPA‐BQ targeted cancer cells and presented low toxicity to normal cells.
Defects have been observed in graphene and are expected to play a key role in its optical, electronic, and magnetic properties. However, because most of the studies focused on the structural ...characterization, the implications of topological defects on the physicochemical properties of graphene remain poorly understood. Here, we demonstrate a bottom-up synthesis of three novel nanographenes (1–3) with well-defined defects in which seven-five-seven (7–5–7)-membered rings were introduced to their sp2 carbon frameworks. From the X-ray crystallographic analysis, compound 1 adopts a nearly planar structure. Compound 2, with an additional five-membered ring compared to 1, possesses a slightly saddle-shaped geometry. Compound 3, which can be regarded as the “head-to-head” fusion of 1 with two bonds, features two saddles connected together. The resultant defective nanographenes 1–3 were well-investigated by UV–vis absorption, cyclic voltammetry, and time-resolved absorption spectra and further corroborated by density functional theory (DFT) calculations. Detailed experimental and theoretical investigations elucidate that these three nanographenes 1–3 exhibit an anti-aromatic character in their ground states and display a high stability under ambient conditions, which contrast with the reported unstable biradicaloid nanographenes that contain heptagons. Our work reported herein offers insights into the understanding of structure-related properties and enables the control of the electronic structures of expanded nanographenes with atomically precise defects.
Aggregation-induced emission (AIE) is a photophysical phenomenon correlated closely with the excited-state intramolecular motions. Although AIE has attracted increasing attention due to the ...significant applications in biomedical and optoelectronics, an in-depth understanding of the excited-state intramolecular motion has yet to be fully developed. Here we found the non-aromatic annulene derivative of cyclooctatetrathiophene shows typical AIE phenomenon in spite of its rotor-free structure. The underlying mechanism is investigated through photoluminescence spectra, time-resolved absorption spectra, theoretical calculations, circular dichroism as well as by pressure-dependent fluorescent spectra etc., which indicate that the aromaticity reversal from ground state to the excited state serves as a driving force for inducing the excited-state intramolecular vibration, leading to the AIE phenomenon. Therefore, aromaticity reversal is demonstrated as a reliable strategy to develop vibrational AIE systems. This work also provides a new viewpoint to understand the excited-state intramolecular motion behavior of lumiongens.
BACKGROUND: The global market for organic food has developed significantly in the past decade. The organic food industry in China is export oriented, with production growing rapidly, although the ...domestic market remains relatively small. This paper surveys 432 consumers from three cities in China, consequently establishing a logit model to analyse the main factors affecting consumers' choice for organic food.RESULTS: The result indicates that Chinese consumers' intent to purchase organic food is strongly affected by factors such as income, degree of trust in organic food, degree of acceptance of organic food price, and consumers' concern on self-health. This intent is only slightly affected by factors such as consumers' age, education level and concern about environmental protection.CONCLUSION: Based on the results, the following measures are recommended: reduce the cost of organic food through multiple channels to cut down the market price; establish and perfect the supervision system of organic food; and promote organic food through various channels. Copyright
► Establishing the (global)constrained stability of the dynamics under mild conditions. ► Extending the original model to the asymmetric case. ► Showing that the feasible set is an invariant set. ► ...Investigating the relationship between this model and a gap function based model. ► Performing numerical experiments to demonstrate the findings.
In this paper, we perform a rigorous analysis on a link-based day-to-day traffic assignment model recently proposed in
He et al. (2010). Several properties, including the invariance set and the constrained stability, of this dynamical process are established. An extension of the model to the asymmetric case is investigated and the stability result is also established under slightly more restrictive assumptions. Numerical experiments are conducted to demonstrate the findings.
Aggregation-induced emission (AIE) is the long-sought solution to the problem of aggregation-caused quenching that has hampered efficient application of fluorescent organic materials. An important ...goal on the way to fully understand the working mechanism of the AIE process was, for more than a decade, and still remains obtaining more comprehensive insights into the correlation between the ultrafast excited-state dynamics in tetraphenylethylene (TPE)-based molecules and the AIE effect in them. Here we report a number of TPE-based derivatives with varying structural rigidities and AIE properties. Using a combination of ultrafast time-resolved spectroscopy and computational studies, we observe a direct correlation between the state-dependent coupling motions and inhibited fluorescence, and prove the existence of photocyclized intermediates in them. We demonstrate that the dominant non-radiative relaxation dynamics,
formation of intermediate or rotation around the elongated Cdouble bond, length as m-dashC bond, is responsible for the AIE effect, which is strongly structure-dependent but not related to structural rigidity.
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