Cobalt sulfide (Co4S3) is considered one of the most promising anode materials for lithium-ion batteries owing to its high specific capacity. However, some disadvantages, such as poor electrical ...conductivity and volume expansion, lead to low rate capability and may hinder its practical applications. Herein, we firstly fabricated leaf-like hollow Co4S3/C nanosheet arrays growing on carbon cloth (h-Co4S3/C NA@CC) by a facile solution method combined with carbonization, sulfidation and annealing treatments. The carbon coated leaf-like nanosheet structure can facilitate the electron transfer and shorten the ion transfer path, while the hollow space inside Co4S3 can buffer the volume variation. As the anode for LIBs, h-Co4S3/C NA@CC demonstrates an impressive rate capability (654.3 mA h g−1 at 1 A g−1 and 394.1 mA h g−1 at 2 A g−1), and an excellent cycling stability (720 mA h g−1 at 1 A g−1 after 200 cycles and 79% capacity retention at 2 A g−1 after 500 cycles).
Dibenzohi,stovalene (DBOV) has excellent photophysical properties, including strong fluorescence and high ambient stability. Moreover, the optical blinking properties of DBOV have enabled optical ...super-resolution single-molecule localization microscopy with an imaging resolution beyond the diffraction limit. Various organic and inorganic fluorescent probes have been developed for super-resolution imaging, but those sensitive to pH and/or metal ions have remained elusive. Here, we report a diaza-derivative of DBOV (N-DBOV), synthesized in eight steps with a total yield of 15%. Nitrogen (N)-bearing zigzag edges were formed through oxidative cyclization of amino groups in the last step. UV–vis and fluorescence spectroscopy of N-DBOV revealed its promising optical properties comparable to those of the parent DBOV, while cyclic voltammetry and density functional theory calculations highlighted its lower orbital energy levels and potential n-type semiconductor character. Notably, in contrast to that of the parent DBOV, the strong luminescence of N-DBOV is dependent on pH and the presence of heavy metal ions, indicating the potential of N-DBOV in sensing applications. N-DBOV also exhibited pH-responsive blinking, which enables pH-sensitive super-resolution imaging. Therefore, N-DBOV appears to be a highly promising candidate for fluorescence sensing in biology and environmental analytics.
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•MiR-183-5p is upregulated in NSCLC.•MiR-183-5p promotes cell proliferation, migration and cell cycle of NSCLC.•MiR-183-5p directly targets PTEN.•MiR-183-5p increases tumor growth and ...metastasis in vivo.
Lung cancer is the leading cause in all cancer deaths. A low survival rate and high recurrence rate of lung cancer make the endeavor to identify new, more effective therapies a primary goal. MicroRNAs (miRNAs) are regarded as regulators of tumorigenesis and it is known that miR-183-5p is significantly upregulated in non-small cell lung cancer (NSCLC), suggesting it has an oncogenic function in lung cancer. In this study, we found that miR-183-5p could promote lung carcinogenesis by directly targeting phosphatase tensin (PTEN). Further experiments indicated that miR-183-5p could suppress p53 and activate AKT signaling through phosphorylation. Moreover, our data indicated that miR-183-5p promoted tumor metastasis and tumor growth in vivo. Collectively, these results showed that miR-183-5p is required for NSCLC development through the suppressing PTEN, and might be a promising target in the diagnosis and treatment of lung cancer in the future.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•An ultra-thin tetraethylammonium based perovskitoid layer was developed to stabilize MAPbI3 perovskite.•The crystal structure and growth orientation of tetraethylammonium based perovskitoid was ...investigated.•The perovskitoid layer can inhibit ion migration and passivate trap states.•A champion efficiency of 21.79% with enhanced stability was achieved for MAPbI3 perovskite.
The efficiency and stability of typical three-dimensional (3D) MAPbI3 perovskite-based solar cells are highly restricted, due to the weak interaction between methylammonium (MA+) and PbI64-octahedra in the 3D structure, which can cause the ion migration and the related defects. Here, we found that the in situ-grown perovskitoid TEAPbI3 layer on 3D MAPbI3 can inhibit the MA+ migration in a polar solvent, thus enhancing the thermal and moisture stability of perovskite films. The crystal structure and orientation of TEAPbI3 are reported for the first time by single crystal and synchrotron radiation analysis. The ultra-thin perovskitoid layer can reduce the trap states and accelerate photo-carrier diffusion in perovskite solar cells, as confirmed by ultra-fast spectroscopy. The power conversion efficiency of TEAPbI3-MAPbI3 based solar cells increases from 18.87% to 21.79% with enhanced stability. This work suggests that passivation and stabilization by in situ-grown perovskitoid can be a promising strategy for efficient and stable perovskite solar cells.
The crystal structure of TEAPbI3 perovskitoid illustrated by single crystal XRD suggested that this perovskitoid has much higher stability than 3D MAPbI3 perovskite. The in situ growth method demonstrated that the formed TEAPbI3 atomic layer on MAPbI3 perovskite can improve the efficiency and stability of MAPbI3 based perovskite solar cells. The formation of atomic perovskitoid layer can not only modify the work function and trap density of MAPbI3 film but also inhibit the MA+ cation migration. Display omitted
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The overburden rock strata fractures and collapses as the extraction of a longwall panel. Knowledge of the extents and characteristics of the fractured zone is important to evaluating many ...mining-induced issues including abutment pressure relief, methane production, and ground subsidence prediction. In this study, a physical model was initially created to produce the process of longwall mining with great attention focused on the caving and fracturing process of the overburden strata. A numerical model was then created according to the geological and geotechnical conditions of the physical model. Both the physical and numerical model successfully captured periodic weighting as the longwall face advances. It is found that periodic weighting does not just involve the local immediate and main roof that composes a cantilever beam right behind the longwall face, it may also involve the rupture of a rock bridge in the overburden strata above the fractured zone. The rock bridge forms and ruptures periodically as longwall mining proceeds. The permeability of a given region in the fractured zone can be evaluated by measuring the area of the voids and fractures within the region. The permeability increases as fracturing and collapse of rock mass within the region and then decreases as the collapsed rock mass compacts. The greater the horizontal-to-vertical stress ratio, the lower the maximum permeability. The more competent the main roof, the lower the maximum permeability.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
In engineering and industry, the function of vitality and mass diffusivity because of heat and density gradients plays an important role. The heat and mass transfer rate depends on the tendency of ...the magnetic field, nature of heat source, thermal radiation, and the variance of concentration of nanofluid. In this study, the significance of variation in nanoparticle’s diameter, dissipation of energy, and mass flux due to the temperature gradient in the convective radiation dynamics of the fluid, heat source, and the Darcy-Forchheimer model over a cylinder has discussed. The basic formulation constituted in the form of coupled non-linear PDEs that has transformed into higher-order ODEs by using peculiar similarity functions. Tiny particles are considered due to their unusual characteristics like extraordinary thermal conductivity, which are significant in advanced nanotechnology, heat exchangers, material sciences, and electronics. The main objective of this comprehensive study is the enhancement of heat transformation. It is observed that if the energy diffusion is relatively higher in intensity due to the concentration gradient, a substantial reduction in temperature distribution throughout the domain is probable in response to increasing copper nanoparticle’s diameter. The concentration gradient leads to a reduction in the viscidness of water-base nanofluids, which leads to an increase in velocity. The convergence of numerical technique is noticed for optimum meshing and the accuracy of the presented results are verified with their exactness to the results as existing in the relevant studies.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Infrared and visible image matching methods have been rising in popularity with the emergence of more kinds of sensors, which provide more applications in visual navigation, precision guidance, image ...fusion, and medical image analysis. In such applications, image matching is utilized for location, fusion, image analysis, and so on. In this paper, an infrared and visible image matching approach, based on distinct wavelength phase congruency (DWPC) and log-Gabor filters, is proposed. Furthermore, this method is modified for non-linear image matching with different physical wavelengths. Phase congruency (PC) theory is utilized to obtain PC images with intrinsic and affluent image features for images containing complex intensity changes or noise. Then, the maximum and minimum moments of the PC images are computed to obtain the corners in the matched images. In order to obtain the descriptors, log-Gabor filters are utilized and overlapping subregions are extracted in a neighborhood of certain pixels. In order to improve the accuracy of the algorithm, the moments of PCs in the original image and a Gaussian smoothed image are combined to detect the corners. Meanwhile, it is improper that the two matched images have the same PC wavelengths, due to the images having different physical wavelengths. Thus, in the experiment, the wavelength of the PC is changed for different physical wavelengths. For realistic application, BiDimRegression method is proposed to compute the similarity between two points set in infrared and visible images. The proposed approach is evaluated on four data sets with 237 pairs of visible and infrared images, and its performance is compared with state-of-the-art approaches: the edge-oriented histogram descriptor (EHD), phase congruency edge-oriented histogram descriptor (PCEHD), and log-Gabor histogram descriptor (LGHD) algorithms. The experimental results indicate that the accuracy rate of the proposed approach is 50% higher than the traditional approaches in infrared and visible images.
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Excessive sedimentation in sand-laden rivers significantly hinders the normal operation and overall effectiveness of reservoirs. This is observed particularly in plain-type sand-laden reservoirs ...where weak hydraulic conditions in the reservoir area contribute to sediment deposition. Water–sediment regulation is essential in reducing sedimentation and prolonging the lifespan of such reservoirs. Taking the plain-type reservoir of the primary stream of the Yellow River—Haibowan Reservoir as an example, based on a two-dimensional shallow water equation, a two-dimensional mathematical model of water and sediment in the reservoir area is established, the corresponding boundary conditions are improved, and the reliability of the model is verified. Under the premise of ensuring the flood control safety of the reservoir dam, considering the impact on the power generation of the reservoir and the downstream river, and maintaining the long-term large effective storage capacity of the reservoir as the basic principle, the water–sediment regulation scheme is proposed. A two-dimensional kinetic model of sediment transport and representative water–sediment series are employed to simulate the erosion and sedimentation processes in the reservoir under different schemes. The optimisation and comparison of multiple schemes reveal that the sediment-flushing scheme, which lowers the water level to 1072 m above sea level when the inflow discharge is 1500–2760 m3/s and inflow sediment concentration is 5–10 kg/m3, can yield an effective reservoir capacity of 97 million m3 and an average annual hydropower generation of 389.5 million kWh after 15 years of operation. This scheme outperforms the existing sediment-flushing scheme and is recommended as an optimised approach for water–sediment regulation in reservoirs. The results of this study provide technical support for the application of water–sediment regulation in the Haibowan Reservoir and may be useful in the exploration and management of water–sediment regulation for plain-type reservoirs on sand-laden rivers.
To investigate the effect of the target weight coefficient on the structure design of the micro-channel heat sink, an innovative method for the topology optimization design of micro-channel ...structures with different bifurcation angles is adopted. In this study, the improved interpolation function, density filtering, and hyperbolic tangent projection methods are adopted to obtain a clear topological structure of the micro-channel heat sink. The heat transfer of the micro-channel heat sink under different bifurcation angles is compared. At the same time, the influence of the two different objective functions, heat transfer, and flow energy consumption, is analyzed in the topology optimization of micro-channel heat sinks. The results show that when the bifurcation angle is 135°, both the heat transfer and the average outlet temperature of the micro-channel heat sink obtain the maximum value, and the heat transfer effect is the best. With the increase of the heat transfer weighting coefficient, the distribution of solid heat sources in the main channel increases, and the refinement of the branch channels also increases. On the other hand, although the heat transfer effect of the micro-channel heat sink is the best, the corresponding flow energy consumption is larger.
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To improve the aerodynamic performance and reduce the noise of multi-blade centrifugal fans used in air conditioners, a bionic groove structure was introduced into the blade tip design, inspired by ...the drag reduction characteristics of mantis shrimp. In this paper, the numerical method was used to investigate the effects of a blade tip bionic groove on the aerodynamic performance and noise characteristics of a multi-blade centrifugal fan. Firstly, the basic design parameters, such as groove width, groove depth, groove center distance, and groove number, were selected to define the shape of the blade tip bionic groove. Then, the effect of the design parameters on the aerodynamic performance of the multi-blade centrifugal fan was studied. Finally, the multi-blade centrifugal fan models with different groove shapes, such as rectangular bionic grooves, circular bionic grooves, and triangular bionic grooves, were established to compare the influence of blade tip groove structures on the aerodynamic performance of the multi-blade centrifugal fan. Through analysis of the aerodynamic performance and noise characteristics of the multi-blade centrifugal fan and the flow fields in the fan impeller, the flow control mechanism of the blade tip bionic groove was revealed. The results showed that the triangular bionic groove on the blade tip had a certain noise reduction effect, although the structural parameters of the bionic groove had little effect on the aerodynamic performance of the multi-blade centrifugal fan. This is because the triangular bionic groove structure can effectively inhibit the vortex shedding at the trailing edge of blade and reduce the flow separation in the impeller passages. As a result, the velocity distribution at the impeller tip became more uniform and the intensity of the tip vortex and the shedding vortex was weakened. Correspondingly, the noise of multi-blade centrifugal fan was also reduced to some extent.
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