Search

The instability of Zn anode caused by severe dendrite growth and side reactions has restricted the practical applications of aqueous zinc-ion batteries (AZIBs). Herein, an enamel-like layer of nanohydroxyapatite (Ca

The irregular and random electrodeposition of zinc has emerged as a non-negligible barrier for deeply rechargeable aqueous zinc (Zn)-ion batteries (AZIBs), yet traditional texture regulation of the Zn substrate cannot continuously induce uniform Zn deposition. Here, a Janus separator is constructed via parallelly grown graphene sheets modified with sulfonic cellulose on one side of the commercial glass fiber separator through the spin-coating technique. The Janus separator can consistently regulate Zn growth toward a locked crystallographic orientation of Zn(002) texture to intercept dendrites. Furthermore, the separator can spontaneously repel SO

The zinc metal anode in aqueous zinc-ion batteries (AZIBs) is considerably impeded by uncontrollable dendrite growth and intricately water-induced corrosion, leading to low Coulombic efficiency (CE) and limited lifespan. Herein, a bifunctional cellulose nanowhisker-graphene (CNG) membrane was constructed to mitigate these problems. Experimental analysis and molecular dynamics simulation reveal that the CNG membrane, functioning as a desolvation layer to preclude H2O molecules encountering the Zn anode, retards the water-induced corrosion reaction. This CNG layer with negative surface charges can simultaneously generate a deanionization shock by spreading cations but screening anions to obtain redirected Zn deposition parallel to the (0002)Zn plane. Furthermore, the flexible and toughened CNG membrane could withstand a strong tensile force (8.54 N) and a great puncture force (0.10 N) to favorably accommodate the Zn anode surface fluctuation during plating/stripping. Accordingly, CNG/Zn anode delivers an enhanced CE (99.4%) and a longer cycle life (∼5500 h), over 27 times that of a bare Zn anode. A full MnO2/graphene-CNG/Zn battery exhibits a high discharge capacity (307 mA h g−1) and maintains a high capacity retention of 87.8% at 5C after 5000 cycles.

Organic batteries with improved electrode wettability will exhibit a better electrochemical performance. How about the relationship between electrode wettability and battery performance in aqueous batteries? Here the effect of cathode wettability in aqueous zinc-ion batteries (AZIBs) on the zinc-ion diffusion and charge transfer based on a research platform of cellulose nanowhiskers (CNWs)/graphene/MnO2 wire-in-scroll nanowires with water contact angles turning from 64.70 ​± ​3.72° to 115.85 ​± ​3.36° as cathodes for AZIBs has been investigated, where the corresponding battery performance shows a parabola trend with the peak in 103.04 ​± ​2.91°. The cathode achieves a high capacity of 384 ​mAh g−1 at 1 ​C and features an ultra-long lifetime of over 5000 cycles at 20 ​C, representing excellent Zn storage performance. A combination of experimental measurements and density functional theory calculations suggests that increased cathode hydrophobicity forces hydrated Zn2+ desolvation at electrode-electrolyte interface, facilitating zinc-ion insertion into host materials, yet extremely hydrophobic cathode leads to sluggish electrochemical kinetics. This study opens a new idea in the design of promising candidates for developing low cost and long lifespan batteries for aqueous systems.

BackgroundWiskott-Aldrich syndrome protein family member 2 (WASF2) has been shown to play an important role in many types of cancer. Therefore, it is worthwhile to further study expression profile of WASF2 in human cancer, which provides new molecular clues about the pathogenesis of ovarian cancer.MethodsWe used a series of bioinformatics methods to comprehensively analyze the relationship between WASF2 and prognosis, tumor microenvironment (TME), immune infiltration, tumor mutational burden (TMB), microsatellite instability (MSI), and tried to find the potential biological processes of WASF2 in ovarian cancer. Biological behaviors of ovarian cancer cells were investigated through CCK8 assay, scratch test and transwell assay. We also compared WASF2 expression between epithelial ovarian cancer tissues and normal ovarian tissues by using immunohistochemical staining.ResultsIn the present study, we found that WASF2 was abnormally expressed across the diverse cancer and significantly correlated with overall survival (OS) and progression-free interval (PFI). More importantly, the WASF2 expression level also significantly related to the TME. Our results also showed that the expression of WASF2 was closely related to immune infiltration and immune-related genes. In addition, WASF2 expression was associated with TMB, MSI, and antitumor drugs sensitivity across various cancer types. Functional bioinformatics analysis demonstrated that the WASF2 might be involved in several signaling pathways and biological processes of ovarian cancer. A risk factor model was found to be predictive for OS in ovarian cancer based on the expression of WASF2. Moreover, in vitro experiments, it was demonstrated that the proliferative, migratory and invasive capacity of ovarian cancer cells was significantly inhibited due to WASF2 knockdown. Finally, the immunohistochemistry data confirmed that WASF2 were highly expressed in ovarian cancer.ConclusionsOur study demonstrated that WASF2 expression was associated with a poor prognosis and may be involved in the development of ovarian cancer, which might be explored as a potential prognostic marker and new targeted treatments.

Due to low cost, environmental friendliness, good safety, superior power density and ease of operation, rechargeable aqueous ion batteries can meet the technical requirements of large-scale energy storage. Compared with aqueous single ion batteries, rechargeable aqueous hybrid ion batteries (RAHBs) have been receiving extensive interest owing to their higher operating voltage and energy density. In this review, we briefly describe the developments and challenges of rechargeable aqueous ion batteries in energy storage and systematically introduce the merits and progress of various rechargeable aqueous hybrid ion batteries. The major issues of different combinations in aqueous hybrid ion batteries along with effective solving strategies are discussed, providing a new perspective for the design and construction of high performance aqueous ion batteries. Ultimately, the challenges and prospects of RAHBs are summarized for future research.

Space-based optical (SBO) sensor is a special kind of star sensor, which can be used in not only the space-based observation for space objects but also satellite navigation, called optical navigation in this paper. The aim of this paper is to design optical navigation strategy for low earth orbit (LEO) satellites, including the selection of beacon objects, and the sensor scheduling for improving navigation accuracy. The processing and observation geometry of space-based optical observation is illustrated first. Based on the characteristics of the space-based optical observation, the distribution of beacon geosynchronous orbit satellites is designed for optical navigation of LEO satellites. And the sensor scheduling criterion for optical navigation is deduced to analyze the characteristics of optical navigation and schedule the navigation mission. It is found that an efficient way to improve the optical navigation accuracy is to add an additional sensor to track other beacon objects, whose line of sight (LOS) should be perpendicular to the original LOS of the sensor as far as possible. Therefore, global positioning system satellites are used as the supplement of beacon objects. Finally, based on the sensor scheduling criterion, navigation for a LEO satellite with two SBO sensors is scheduled, which obtains more accurate results and converges more rapidly.

The role of negative charges on cellulose nanowhiskers (CNWs) in the aqueous dispersion behaviors of graphene has been investigated. The sulfate groups were partially removed from the CNWs with sodium hydroxide solution. Both CNWs and desulfated cellulose nanowhiskers (D-CNWs) were applied in the aqueous dispersion process of graphene. The dispersing result was evaluated by ultraviolet-visible (UV-Vis) absorption spectra. It revealed the dispersing ability of D-CNWs became worse due to the removal of sulfate groups. It demonstrated the negative charged sulfate groups on CNWs played an important role in the graphene dispersing process.

Two-dimensional transition metal carbides (nitrides) MXenes have excellent electrochemical properties and be hoped as a promising electrode material for supercapacitors. However, MXene nanosheets are prone to aggregate due to van der Waals interaction, which affect its electrochemical performance. In this study, nitrogen-doped Ti3C2 (N-Ti3C2), which hydrothermally prepared from MXene Ti3C2, was assembled with metallic zinc to obtain a hybrid capacitor system in 1 M ZnSO4 aqueous electrolyte. In the voltage range of 0.05–1.2 V, the specific capacitance of this capacitor can reach 247.9 F g−1 (corresponding to an energy of 45.54 Wh kg−1). At high current density, it can quickly charge and discharge in 27 s, accompanied a high power output of 4093 W kg−1 and an energy of 30.99 Wh kg−1. It presents an outstanding cycling stability with 88.34% capacity retention over 6000 cycles. The self-discharge rate in 240 h is only 1.24 mV h−1. The high electrochemical performance mainly based on the introduction of nitrogen heteroatoms in cathode of N-Ti3C2, which show the ion adsorption/desorption, and the deposition/exfoliation of Zn (Zn2+) on the Zn anode to combine a hybrid capacitor.

Aqueous rechargeable sodium ion batteries (ASIBs) are low-cost and highly safe, which deserves more research in electrochemical energy storage systems. However, the developments of ASIBs are limited by its narrower thermodynamic voltage window (1.23 V) and lower energy density compared to the organic system. Therefore, widening the stable window of aqueous electrolyte and finding the new electrode materials of high capacity have become the focus of ASIBs researches. This review overviews the recent developments in electrode materials, and strategies for widening the stable window of aqueous electrolyte and constructing long-life for ASIBs. This review also briefly discusses the future challenges and perspectives of ASIBs.

Development of a model for the analysis of strain transfer mechanism in Brillouin-based sensors with strain singularities is provided in this study. The main objective of the research pertained to the development of a method for accurate detection of cracks and their locations in sensing with Brillouin-based fiber optic distributed sensors. The work involved formulation of a shear lag–based model considering the elastic as well as elastoplastic stages of the fiber optic coating strains. Feasibility of the proposed approach is evaluated through an experimental program. The experimental program involved use of a Brillouin optical time domain reflectometer (BOTDR) for distributed measurement of strain and detection of simulated cracks in a 15-m-long beam. The results indicate that the discontinuities in the strain distribution based on the theoretical analysis provide the means to accurately pinpoint the location of simulated cracks. On the other hand, the distortion effect of the BOTDR system due to...

The influence of thermal treatment on the resistance switching of SrTiO 3 :Nb (0.05 and 0.5 wt.% Nb) single crystals has been investigated. Analyzing current–voltage and capacitance–frequency curves of samples demonstrate that thermal treatment could increase interface state by improving the chemisorbed oxygen concentration on the surface. Switching time of Pt/SNTO junction with both the thermal treatment and the electroforming would be further shortened. The model of resistance switching effect is attributed to the trapping/detrapping electrons at the interface. These results above are useful for further comprehension of resistance switching mechanism.

Development of a simplified approach for monitoring the cables of cable-stayed bridges is described in this article. The method introduced in this paper uses the distributed measurement of strains along the bridge deck to detect the cables that have totally or partially lost their tensile force. The fundamental principle employed in formulating the method is the interrelationship between the individual cable forces and the bending moment along the bridge span. The proposed method was evaluated through an experimental program that involved fabrication and testing of a reduced scale model of a single plane cable-stayed bridge. Distributed strain along the span length was monitored by a Brillouin Optical (Neubrex, Hyogo, Japan) Time Domain Analysis fiber optic sensor system. Strain gauges, Fiber Bragg Grating sensors (Technica Optical Component, LLC, Beijing, China), and a finite element model of the bridge were employed for evaluating the efficiency of the proposed method. Several different damage c...

Distributed sensing offers great promise in structural health monitoring of bridges and other types of critical structures. Over the years, a number of different Brillouin scattering–based systems have been developed for distributed sensing, including sensors based on the Brillouin optical time domain reflectometer. This study pertains to the quantitative characterization of Brillouin optical time domain reflectometer–based sensors for monitoring of distributed strains and detection of defects. This study involved experiments involving a 15-m-long beam and simulated defects. In the experiments, the effect of strain localization at the defect sites was masked by the low spatial resolution of the Brillouin optical time domain reflectometer. The Brillouin optical time domain reflectometer–measured response was evaluated by numerical modeling of the beam. Computation of the flexural strains involved a hybrid approach in which the experimentally determined degraded stiffnesses of the defect zones were employed...

Hydrogenated Mn doped Zn1−xMnxO (x = 0.03, 0.04, 0.08) nanoparticles were prepared by co-precipitation method. With the increase of Mn ions concentration, the magnetization of the hydrogenated Zn1−xMnxO increased. Photoluminescence spectra of samples annealed in Ar and H2 respectively were performed and the visible bands were fitted with Gaussian analysis. It is concluded that the sharp magnetization enhancement could be attributed to the long-rang interaction between bound-magnetic-polarons led by the singly charged oxygen vacancy (Vo+).

Brillouin scattering–based fiber-optic sensors have been used in a number of applications, including monitoring of pipelines and well-casing damage in the oil and gas industry. The major attribute of these sensors is their capability for distributed sensing of strains along large sections of structures. For these reasons, Brillouin-based fiber-optic sensors have great potential for civil structural applications, such as in bridges. This study reports the investigation of the Brillouin optical time-domain reflectometer for assessing damage in structural members. The primary advantage in using the Brillouin optical time-domain reflectometer is the single-fiber installation and multidamage-detection capability for the entire structure. The challenge in using a Brillouin optical time-domain reflectometer for detection of localized damage is to overcome the effects of system noise and Brillouin frequency-peak shift distortions. The compound effects of noise and frequency-peak distortions result in disp...

A novel methodology for the determination of the coefficient of thermal expansion (CTE) is proposed by using long-gauge fiber optic sensors. Current approaches either neglect the shear-lag effects or do not compensate for the thermo-optic effects in optical fibers leading to precision errors. The embedded long-gauge sensor measures not only the thermo-optic effect due to temperature fluctuations, but also the strain-optic effect created by thermal stresses. However, it is difficult to directly separate these two effects in the measurements. Given that only the strain-optic effect correlates to the CTE of a host material, it is necessary to compensate for the thermo-optic effect. An additional error is attributed to the fact that the shear-lag effect is ignored, i.e. assumption is made that the strain distribution in the optical fiber is the same as that in the host material. This study reports on the development of a methodology for the computation of the coefficient of thermal expansion in structural materials using long-gauge fiber optic sensors. The proposed formulations account for both the shear-lag and thermo-optic effects.