Recently, all-inorganic perovskite quantum dots (QDs) (CsPbX
3
, X = Cl, Br, I) as the emerging semiconductor materials have been intensively studied owing to superior optical properties. Currently, ...the strategy for preparation of inorganic perovskite QDs mainly focuses on the hot-injection method, but requires inert gas protection and is difficult to mass-produce. In this work, we developed a simple and low-cost strategy for preparing highly luminescent and air-stable all-inorganic perovskite QDs by directly heating perovskite precursors in octane in air. The emission wavelength of CsPbX
3
perovskite QDs can be tunable from ultraviolet (UV) to infrared region by simply controlling their halide composition and display high PLQYs. Moreover, CsPbX
3
perovskite QDs in octane can exist more than half a year in air and the film of CsPbX
3
perovskite QDs also shows good thermal stability and air stability, especially high iodide-substituted CsPbBr
3−
x
I
x
perovskite QDs. The CsPbX
3
perovskite QDs can be easily blended with PDMS and used as color conversion layer on the blue LEDs chip for high-quality white LEDs. Our work opens a window for the potential application of such highly luminescent material in the fields of multicolor LEDs, backlight display and other related optoelectronic devices.
Calcium-ion batteries are promising candidate as alternative to lithium-ion batteries with appealing features of abundant resource and high theoretical specific capacity up to 1337 mAh g−1. However, ...the development of calcium-ion batteries is primarily hindered by the lack of satisfactory electrode materials due to the large radius and charge density of calcium ion. Herein, we report the reversible calcium ion intercalation in layered potassium vanadate K2V6O16·2.7H2O as stable cathode with impressive electrochemical performance for Ca ion battery. The potassium vanadate nanowires obtained by facile hydrothermal process (typical lengths of 0.5–1.5 μm, widths of 70–100 nm) deliver a high initial capacity of 113.9 mAh g−1 at current density of 20 mA g−1 and high capacity retention of 78.30% at 50 mA g−1 after 100 cycles. In addition, the reversible intercalation of calcium ion in this layered potassium vanadate material with stable crystal structure is verified by ex-situ XPS and XRD techniques, demonstrating that layered K2V6O16·2.7H2O could be a potential cathode material for calcium-ion batteries.
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•Layered potassium vanadate K2V6O16 is investigated as Ca-ions battery cathode.•High discharge capacity of 113.9 mAh g−1 with retention of 78.3% were achieved.•Reversible Ca2+ insertion/extraction and high structure stability were verified.
The gut microbiota is a complex ecosystem consisted of trillions of microbes that have co-evolved with their host for hundreds of millions of years. During the last decade, a growing body of ...knowledge has suggested that there is a compelling set of connections among diet, gut microbiota and human health. Various physiological functions of the host, ranging from metabolic and immune regulation to nerve and endocrine development, are possibly mediated by the structural components of microbial cell or the products of microbial metabolism, which are greatly influenced by dietary macronutrients and micronutrients. Thus, governing the production and activity of these microbial-associated small molecules and metabolites through dietary intervention may provide promising strategies for the improvement of human health and disease. In this review article, we first provide an overview of current findings about the intimate interrelationships between diet and gut microbiota. We also introduce the physiological effects of some microbial-associated small molecules and metabolites on the host as well as the detailed signaling mechanisms.
Exosomes (Exos) are endogenous nanocarriers that have utility as novel delivery systems for the treatment of brain cancers. However, in general, natural Exos show limited BBB-crossing capacity and ...lack specific targeting. Further modifications including targeting peptides and genetic engineering approaches can circumvent these issues, but the process is time-consuming. Focused ultrasound (FUS) has been approved by the Food and Drug Administration for the diagnosis and treatment of brain diseases due to its noninvasive nature, reversibility, and instantaneous local opening of the BBB. In this study, we developed a natural and safe transportation system using FUS to increase the targeted delivery of Exos for glioma therapy. We also compared the advantages of macrophage-derived Exos (R-Exos) and blood serum-derived Exos (B-Exos) to screen for an improved platform with scope for clinical transformation. In vitro, both R-Exos and B-Exos were transported through BBB models and accumulated in glioma cells with the assistance of ultrasound exposure. R-Exos and B-Exos displayed no obvious differences in physical characteristics, drug release, tumor targeting, and cytotoxicity when combined with FUS. In vivo animal imaging studies suggested that the fluorescence intensity of B-Exos plus single FUS in brains was 4.45-fold higher than that of B-Exos alone. Furthermore, B-Exos plus twice FUS treatment efficiently suppressed glioma growth with no obvious side effects. We therefore demonstrate that the combination of FUS and naturally abundant B-Exos is a potent strategy for brain cancer therapeutics.
Aqueous V2O5–Zn batteries, an alternative chemistry format that is inherently safer to operate than lithium‐based batteries, illuminates the low‐cost deployment of the stationary energy storage ...devices. However, the cathode structure collapse caused by H2O co‐insertion in aqueous solution dramatically deteriorates the electrochemical performance and hampers the operation reliability of V2O5–Zn batteries. The real‐time phase tracking and the density functional theory (DFT) calculation prove the high energy barrier that inhibits the Zn2+ diffusion into the bulk V2O5, instead the ZnCl2 “water‐in‐salt electrolyte” (WiSE) can enable the dominant proton insertion with negligible lattice strain or particle fragment. Thus, ZnCl2 WiSE enables the enhanced reversibility and extended shelf life of the V2O5–Zn battery upon the high temperature storage. The improved electrochemical performance also benefits by the inhibition of vanadium cation dissolution, enlarged voltage window, as well as the suppression of the Zn dendrite protrusion. This study comprehensively elucidates the pivotal role of a concentrated ZnCl2 electrolyte to stabilize the aqueous batteries at both the static storage and dynamic operation scenarios.
The application of ZnCl2 “water‐in‐salt” electrolyte in V2O5—Zn battery can effectively enhance the electrochemical performance no matter in dynamic or static conditions. This improvement is ascribed to the inhibition of cathode dissolution, extended voltage window, and the suppression of the Zn dendrite protrusion. Moreover, it is proved that proton inertion contributes most of the capacity, benefiting the particle integrity.
With the development of information transmission, there is an increasing demand for state monitoring of fiber-optic communication networks to improve the security and self-healing ability of the ...network. Distributed optical fiber sensing is one of the most attractive methods because it can achieve real-time detection of the whole network without additional sensing heads. However, when the sensing network is introduced into the communication network, the failure probability should be efficiently suppressed with limited sensing resources. In this paper, the fuzzy logic system is used to evaluate the impact of different sensing resource allocation on optical cable network quality. The link failure probability and path failure probability under the condition of uniform and non-uniform sensing resource allocation are simulated and analyzed, respectively. As shown in the analysis results, the failure probability under non-uniform allocation is significantly lower than under uniform allocation. In this paper, we discussed and addressed the allocation of the optical fiber sensing and communication integrated (OFSCI) network with the limited sensing resource for the first time. The results are helpful to develop an allocation strategy for optical fiber sensing and a communication integrated network with a higher robustness.
Nucleoside analogs play a crucial role in the production of high-value antitumor and antimicrobial drugs. Currently, nucleoside analogs are mainly obtained through nucleic acid degradation, chemical ...synthesis, and biotransformation. However, these methods face several challenges, such as low concentration of the main product, the presence of complex matrices, and the generation of numerous by-products that significantly limit the development of new drugs and their pharmacological studies. Therefore, this work aims to summarize the universal separation methods of nucleoside analogs, including crystallization, high-performance liquid chromatography (HPLC), column chromatography, solvent extraction, and adsorption. The review also explores the application of molecular imprinting techniques (MITs) in enhancing the identification of the separation process. It compares existing studies reported on adsorbents of molecularly imprinted polymers (MIPs) for the separation of nucleoside analogs. The development of new methods for selective separation and purification of nucleosides is vital to improving the efficiency and quality of nucleoside production. It enables us to obtain nucleoside products that are essential for the development of antitumor and antiviral drugs. Additionally, these methods possess immense potential in the prevention and control of serious diseases, offering significant economic, social, and scientific benefits to the fields of environment, biomedical research, and clinical therapeutics.
The question of whether spatial attention can modulate initial afferent activity in area V1, as measured by the earliest visual event‐related potential (ERP) component “C1”, is still the subject of ...debate. Because attention always enhances behavioral performance, previous research has focused on finding evidence of attention‐related enhancements in visual neural responses. However, recent psychophysical studies revealed a complex picture of attention's influence on visual perception: attention amplifies the perceived contrast of low‐contrast stimuli while dampening the perceived contrast of high‐contrast stimuli. This evidence suggests that attention may not invariably augment visual neural responses but could instead exert inhibitory effects under certain circumstances. Whether this bi‐directional modulation of attention also manifests in C1 and whether the modulation of C1 underpins the attentional influence on contrast perception remain unknown. To address these questions, we conducted two experiments (N = 67 in total) by employing a combination of behavioral and ERP methodologies. Our results did not unveil a uniform attentional enhancement or attenuation effect of C1 across all subjects. However, an intriguing correlation between the attentional effects of C1 and contrast appearance for high‐contrast stimuli did emerge, revealing an association between attentional modulation of C1 and the attentional modulation of contrast appearance. This finding offers new insights into the relationship between attention, perceptual experience, and early visual neural processing, suggesting that the attentional effect on subjective visual perception could be mediated by the attentional modulation of the earliest visual cortical response.
Our findings reveal a positive correlation between attentional modulations on the C1 component and subjective contrast perception. Although the averaged C1 attention effect across participants did not reach statistical significance, our finding implies that the attentional modulation of neural responses in V1 may contribute to the attention effect on visual perception.
Cracks in road surfaces are among the most critical problems in the management of expressways. Their sizes, which not only have severe consequences in relation to expressway safety, decide ...maintenance timing, which if accurately estimated, can prevent the rapid development of crack disease. Currently, the main techniques used for crack size measurement makes use of either human inspection or sophisticated mobile equipment, which are respectively, very time consuming, labour-intensive, and difficult to implement in civil engineering. Thus, there is great interest in practical and highly efficacious automated crack identification systems coupled with low-cost data-processing sensors. A PTZ (pan/tilt/zoom) camera-based image processing idea is investigated in this paper for crack size measurement in expressways in China. The proposed method consists of four steps: 1) image acquisition, 2) corner-based line size calculation, 3) pixel size calculation, and 4) crack size estimation. A case study of roadway lane images and crack images, collected from China G4/Jingshi, is conducted to demonstrate the feasibility of the proposed method. The results demonstrate that PTZ camera-based image processing is capable of efficiently quantifying cracks, obtaining high accuracy crack size results at range of 0 m to 40 m. The method shows promise for crack size measurement in a cost-effective manner and can provide an objective and timely means for transportation agencies to conduct maintenance plans.
In order to quantitatively calculate the critical depth and critical load of mines affected by rock burst, and to achieve effective prevention and control of rock burst in coal mines, this paper ...proposes a mechanical model for predicting the occurrence of rock burst in coal mine roadways based on catastrophe theory. Additionally, a theoretical calculation formula for initiating rock burst is derived. The first step was to establish a mechanical analysis model, which directly correlated with the in-situ stress, physical and mechanical characteristics of the coal-rock mass, and engineering structural parameters. Following this, a mechanical instability criterion was derived for the key load-bearing circle within the surrounding rock of the roadway. In the final step, the critical depth and load for rock burst initiation were verified for 25 distinct coal mines in China that were prone to rock burst hazards. The research results demonstrate that the discrepancy between the theoretically calculated critical depth and the actual measured statistical values was less than 35%. In addition, the difference between the theoretically determined critical depth and the value calculated by Pan Yishan was less than 32%. Notably, the ratio of the theoretically calculated critical load to the uniaxial compressive strength of the coal-rock mass ranged from 0.38 to 1.93. This aligns with empirical data on rock burst occurrences, as set out in the engineering classification standards for rock masses. These research outcomes substantiated the practical utility of the proposed theory, thereby laying a robust theoretical groundwork for the quantitative control of rock burst.
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