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With the wide application of graphene oxide nanoparticles (GONPs), a great amount of GONP waste is discarded and concentrated in landfills. It has been proven that GONPs have strong toxicity and could gather toxic substances due to their high adsorption capacity. GONPs will seriously pollute the surrounding environment if they leak through the geosynthetic clay liner (GCL) in landfills. To investigate various factors (temperature, ionic strength (IS) and humic acid (HA)) on the transport and retention of GONPs in the GCL, a self-designed apparatus was created and column tests were carried out. The experimental results show that GONPs could be transported through the GCL. The mobility and sorption ratio of GONPs in GCL decreased with an increase in temperature and IS, and increased with an increase in HA. The temperature had little effect on the deposition ratio of GONPs in the GCL. The deposition ratio of GONPs in the GCL increased with IS, and decreased with an increase in HA. The transport of GONPs in GCL, glass beads and quartz sand was compared, and the results show that the retention ability of the GCL is much better than other porous materials. The experimental results could provide significant references for the pollution treatment in landfills. [ABSTRACT FROM AUTHOR]

This study focuses on the effect of Cu doping on the thermoelectric properties of BiSbTe3 (BST) alloys. Firstly, we successfully prepared high-quality BST alloys using the KCl solvent method and selected the most promising BST(KCl)3.5 sample from them, followed by Cu doping experiments. The experimental results show that Cu doping significantly improves the crystal quality and density of the alloy, thereby increasing the material's mobility and reducing the resistivity, leading to an improvement in the power factor. However, Cu doping also introduces a large number of dislocations and lattice distortions. Additionally, the highly doped samples contain Cu2Te and BST superlattice structures, which further enhance the scattering of heat transfer phonons, significantly reducing the lattice thermal conductivity. In the experiment, Cu-doped samples exhibited extremely low lattice thermal conductivity, as low as 0.32 W m−1 K−1 at 300 K. These improvements in structure and performance have greatly enhanced the thermoelectric efficiency of Cu-doped samples, leading to a significant increase in their ZT values. Particularly, in samples with a Cu doping level of x = 0.01, the maximum ZT value was 1.47 at 400 K, and the average ZT value reached 1.28 in the temperature range of 300 K to 450 K. These findings underscore the wide-ranging application potential of Cu-doped BiSbTe3 alloys in room temperature refrigeration and power generation. The study provides crucial insights into the characteristics of Cu-doped BiSbTe3 alloys, while also contributing to the optimization of thermoelectric material design and the advancement of sustainable energy conversion technologies. [ABSTRACT FROM AUTHOR]

A large number of non-degradable materials have severely damaged the ecological environment. Now, people are increasingly pursuing the use of environmentally friendly materials to replace traditional chemical materials. Polyhydroxyalkonates (PHAs) are receiving increasing attention because of the unique biodegradability and biocompatibility they offer. However, the applications of PHAs are still limited due to high production costs and insufficient study. This project examines the optimal electrospinning parameters for the production of PHA-based fibrous membranes for air filtration. A common biodegradable polyester, Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), was electrospun into a nanofibrous membrane with a well-controlled surface microstructure. In order to produce smooth, bead-free fibers with micron-scale diameters, the effect of the process parameters (applied electric field, solution flow rate, inner diameter of hollow needle, and polymer concentration) on the electrospun fiber microstructure was optimized. The well-defined fibrous structure was optimized at an applied electric field of 20 kV, flow rate of 0.5 mL/h, solution concentration of 12 wt.%, and needle inner diameter of 0.21 mm. The morphology of the electrospun PHBV fibrous membrane was observed by scanning electron microscopy (SEM). Fourier transform infrared (FTIR) and Raman spectroscopy were used to explore the chemical signatures and phases of the electrospun PHBV nanofiber. The ball burst strength (BBS) was measured to assess the mechanical strength of the membrane. The small pore size of the nanofiber membranes ensured they had good application prospects in the field of air filtration. The particle filtration efficiency (PFE) of the optimized electrospun PHBV fibrous membrane was above 98% at standard atmospheric pressure. [ABSTRACT FROM AUTHOR]

The variation in seasonal conditions causes an impact on the wood–water relations and dimensional stability like shrinkage and swelling with solar drying technology, leading to discrepancies in drying qualities. To address this processing problem, we studied the pattern of drying kinetics and dimensional changes in four seasons and Northeast China. The experimental analysis shows that the Page, the Aghbashlo et al., the two-term exponential, and the Weibull models may be applied to emulate solar drying kinetics during different seasons of poplar timber. The results also show that the diffusion coefficients fall below the range of 6.01 × 10–11 to 1.52 × 10–9 m2/s, the activation energy mean is 32.74 kJ mol−1, and the R2 is 0.84 and the wood dimensional changes during the drying are in descending order of summer, spring, winter, and fall. Conclusively, solar timber drying is seasonally affected, and related studies are needed to provide a theoretical basis to develop the numerical modeling, and a thermo-mass-mechanical multi-physics coupled model for the seasonality of solar drying. This research will eventually provide references for improving the application of solar drying technology in different regions of the world, such as the development of heat storage media in different seasons, the upgrade of drying equipment, and the standardization of solar intermittent drying schedules. [ABSTRACT FROM AUTHOR]

It is known that nested states composed of ring-shaped hidden vorticity quantum droplets (QDs) with topological charges (S 2 = − S 1 , referred to as hidden vorticity) are stable in binary Bose-Einstein condensates (BECs). However, this nested multiring states with hidden vorticity are very extreme cases. Hence, the nested patterns with different topological charges are worth studying. In this paper, we use the imaginary-time-integration method to obtain for the first time the ring-shaped QDs with high topological charge (up to S 2 = 15) in a radially periodic potential. We analyzed in detail the influence of the modulation depth on the stability of the ring-shaped QDs. The trapping capacity of the troughs is studied with fixed modulation depth. Finally, we obtain the nested patterns constructed by ring-shaped QDs with different topological charges, greatly expanding the encoding of topological states. The results provide reference for designing data storage devices using vortex topology charges. • We have studied the ring-shaped QDs with arbitrary topological charges in a radially periodic potential. • We have analyzed stability intervals for the ring-shaped QDs, and studied the trapping capacity of the circular troughs. • We have obtained the stable nested vortex modes constructed by ring-shaped QDs with different topological charges. [ABSTRACT FROM AUTHOR]

High dynamic range (HDR) images have recently drawn much attention in multimedia community. In this paper, we proposed an HDR image steganography method based on deep learning, which is for HDR images with OpenEXR format. To the best of our knowledge, this is the first steganography method that applies deep learning to HDR image steganography, and the first steganography method that hides images in HDR images. The LDR secret image is hidden in the mantissa of the HDR cover image of the same size through a hidden network, and recovered through an extraction network in the receiver. Experimental results show that the proposed algorithm has advantages in security, robustness and capacity compared with other “hiding image in image” algorithms. [ABSTRACT FROM AUTHOR]

Head and neck squamous cell carcinoma (HNSCC) is a common malignant tumour. Despite advancements in surgery, radiotherapy and chemotherapy, which have improved the prognosis of most patients, a subset of patients with poor prognoses still exist due to loss of surgical opportunities, postoperative recurrence, and metastasis, among other reasons. The tumour microenvironment (TME) is a complex organization composed of tumour, stromal, and endothelial cells. Communication and interaction between tumours and immune cells within the TME are increasingly being recognized as pivotal in inhibiting or promoting tumour development. Previous studies on T cells in the TME of HNSCC have yielded novel therapeutic possibilities. However, the function of B cells, another adaptive immune cell type, in the TME of HNSCC patients has yet to be determined. Recent studies have revealed various distinct subtypes of B cells and tertiary lymphoid structures (TLSs) in the TME of HNSCC patients, which are believed to impact the efficacy of immune checkpoint inhibitors (ICIs). Therefore, this paper focuses on B cells in the TME to explore potential directions for future immunotherapy for HNSCC. [ABSTRACT FROM AUTHOR]

[Display omitted] • Species richness hotspots were identified by multi-species distribution modeling. • The magnitude and direction of future biodiversity hotspots changes were discussed. • The MaxEnt and InVEST models were complementary in biodiversity conservation. • Suggestions for biodiversity conservation were proposed based on gap analysis. Mainstreaming biodiversity into protection planning and management is of great significance for biodiversity conservation and sustainable development. Species potential distribution modeling is an effective way for species diversity evaluation and biodiversity hotspots identification, which are crucial for biodiversity conservation. Taking the Central Urban Area of Chongqing Municipality as the study area, the main objectives of this study were to identify the potentially suitable habitats, species richness and biodiversity of key protected species in current and future, determine the relative contribution of environmental factors and assess the conservation effectiveness of protected areas (PAs) based on MaxEnt model and gap analysis. The results showed that the current potentially suitable habitats of total key protected species were mainly located in "two rivers and four mountains", with a total area of 1610.55 km2, of which forestland accounted for 59.78 %. Species suitable habitats demonstrated clear topographic heterogeneity, and the distribution index decreased at first and then increased with increasing terrain niche index (TNI). Meanwhile, it was observed that key protected plants and birds shared similar suitable habitats in mountainous areas, with an overlapping area of 753.53 km2, and the high species richness covered 182.83 km2. In 2050, the future biodiversity hotspots would remain stable and increase steadily. In terms of the direction of centroid shift, the biodiversity hotspots would migrate to low latitude, low altitude and southeast by 8.34 km. The jackknife tests indicated that the potential distribution of key protected species was mainly determined by land use, mean diurnal range and TNI. Additionally, the problems of high protection gaps and low protection effectiveness coexisted in the existing PAs, with the overlapping area of the comprehensive biodiversity hotspots and the existing PAs was only 446.96 km2. Finally, suggestions for natural PAs system optimization and ecological protection were proposed. This study provides scientific supports for biodiversity conservation and efficient management. [ABSTRACT FROM AUTHOR]