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Lithium has broad applications in several emerging industries and fields, including high energy batteries, energy storage, aerospace, and controlled nuclear reactions. Currently, the discrepancy between the supply and demand for lithium resources increases, and its distribution is uneven. Within the framework of the "Belt and Road" Initiative, the lithium trade pattern evolves constantly. However, the trade pattern of lithium in the nations along the "Belt and Road" is likely to face substantial repercussions in modern world of unilateral protectionism and geopolitical conflicts. Taking the social network analysis approach as a tool, this study first examines the characteristics of the lithium trade network structure as it has evolved over the years in the Belt and Road countries, from 2000 to 2022. Additionally, this study uses the quadratic assignment problem approach to analyze the factors influencing the evolution of the lithium trade network. The study shows that: (1) The spatial patterns of import and export trade network of lithium in countries along the route has a certain path dependence. And the market is mainly concentrated in East Asia, Central and Eastern Europe, South America and Southeast Asia. (2) The network density of the countries along the route has increased year after year, but it remains low. And the fluctuation of the network's reciprocity has increased, with a huge magnitude of variation. The number of core countries in the network has decreased over time, but the core-periphery structure has stayed largely steady. China, Chile, and South Korea are the network's main node countries. (3) Regarding the influencing factors, the differences in economic and technological development between these countries have a beneficial impact on the formation of lithium trade; whether or not regional trade agreements have been signed, the differences about average tax rates for mineral products, bordering countries, and similar languages and cultures are all conducive to the establishment of close trade links. The contribution of this essay is of paramount importance for understanding different countries' role along the Belt and Road in the lithium trade network pattern, and promoting regional trade cooperation. [ABSTRACT FROM AUTHOR]

C-SAR/01 and C-SAR/02 serve as successors to the GF-3 satellite. They are designed to operate in tandem with GF-3, collectively forming a C-band synthetic aperture radar (SAR) satellite constellation. This constellation aims to achieve 1 m resolution imaging with a revisit rate of one day. It can effectively cater to various applications such as marine disaster prevention, monitoring marine dynamic environments, and supporting marine scientific research, disaster mitigation, environmental protection, and agriculture. Geometric correction plays a pivotal role in acquiring highly precise geographic location data for ground targets. The geometric positioning accuracy without control points signifies the SAR satellite's geometric performance. However, SAR images do not exhibit a straightforward image-point–object-point correspondence, unlike optical images. In this study, we introduce a novel approach employing high-precision automatic trihedral corner reflectors as ground control points (GCPs) to assess the geometric positioning accuracy of SAR images. A series of satellite-ground synchronization experiments was conducted at the Xilinhot SAR satellite calibration and validation site to evaluate the geometric positioning accuracy of different C-SAR image modes. Firstly, we calculated the azimuth and elevation angles of the corner reflectors based on satellite orbit parameters. During satellite transit, these corner reflectors were automatically adjusted to align with the radar-looking direction. We subsequently measured the exact longitude and latitude coordinates of the corner reflector vertex in situ using a high-precision real-time kinematics instrument. Next, we computed the theoretical image coordinates of the corner reflectors using the rational polynomial coefficients (RPC) model. After that, we determined the accurate position of the corner reflector in the Single Look Complex (SLC) SAR image using FFT interpolation and the sliding window method. Finally, we evaluated and validated the geometric positioning accuracy of C-SAR images by comparing the two coordinates. The preliminary results indicate that the positioning accuracy varies based on the satellite, imaging modes, and orbital directions. Nevertheless, for most sample points, the range positioning accuracy was better than 60 m, and the azimuth positioning accuracy was better than 80 m. These findings can serve as a valuable reference for subsequent applications of C-SAR satellites. [ABSTRACT FROM AUTHOR]

Copying with the increasingly severe energy crisis and air pollution, new energy vehicles will be an inexorable trend in the near future. The E-Cell electric engineering vehicles will replace conventional oil-fired ones gradually. This paper analyses the current situation and tendency of EVs in brief, explains the function of E-Cell electric engineering vehicles and its roles in maintaining grid stability, peak load shifting and 24-hour emergency rescue service for EVs. Concerning technical application, this paper primarily designs vehicle intelligent terminal systems, Battery Management System(BMS), cable charging, wireless charging and self-charging systems. Finally, this paper designs the billing modes of charging process, and accounts for billing process of vehicle intelligent terminal systems by flow chart to ensure the accuracy during charging process.

Validation is the basis of synthetic aperture radar (SAR) image quantification applications. Based on the point target of the field site, the radiation characteristics of the backscattering coefficient image can be used to optimize the SAR imaging, and the product production system can be more closely targeted, to ensure the image product accuracy in the actual quantification application. In this study, the validation of the backscattering coefficient image was examined using calibrators, and the radiometric properties of the image were evaluated by extracting the radar cross-section of each point target. Bilinear interpolation and fast Fourier transform (FFT) interpolation methods were introduced for the local area interpolation of point targets, and the two methods were compared from the perspective of response function imaging and validation accuracy. The results show that the FFT interpolation method is more favorable for validating the backscattering coefficient. [ABSTRACT FROM AUTHOR]

C-SAR/01, the successor of China's Gaofen-3 Satellite, which launched on 23 November 2021, is the first synthetic aperture radar (SAR) satellite to be launched in China's civil space infrastructure plan and has served as an invaluable data resource. Radiometric calibration and validation are prerequisites for the quantitative application of SAR data. In this study, the radiometric calibration experiments of C-SAR/01 data of the ultra-fine strip (UFS) and fine strip I (FSI) modes were conducted applying flexible automatic triangular trihedral corner reflectors deployed in Xilinhot SAR satellite calibration and validation site. Accordingly, the image quality and radiometric calibration accuracy were evaluated. The results show that the spatial resolution, peak sidelobe ratio, and integrated sidelobe ratio of UFS and FSI mode data of C-SAR/01 are better than those of the design indexes, and the calibration results from the integral method are more stable than those from the peak method. Furthermore, the standard deviation of the calibration constant for UFS mode data is 0.234 dB, with the relative and absolute calibration accuracies obtained as 0.233 and 0.532 dB, respectively, whereas the standard deviation calibration constant for FSI mode data is 0.198 dB, with its relative and absolute calibration accuracies evaluated as 0.199 and 0.333 dB, respectively. [ABSTRACT FROM AUTHOR]

Terahertz (THz) meta-devices are considered to be a promising framework for constructing integrated photonic circuitry, which is significant for processing the upsurge of data brought about by next-generation telecommunications. However, present active metasurfaces are typically restricted by a single external driving field, a single modulated frequency, fixed switching speed, and deficiency in logical operation functions which prevents devices from further practical applications. Here, to overcome these limitations, we propose a hybrid THz metasurface consisting of vanadium dioxide (VO2) and germanium (Ge) that enables electrical and optical tuning methods individually or simultaneously and theoretically investigate its performance. Each of the two materials is arranged in the meta-atom to dominate the resonance strength of toroidal or magnetic dipoles. Controlled by either or both of the external excitations, the device can switch on or off at four different frequencies, possessing two temporal degrees of freedom in terms of manipulation when considering the nonvolatility of VO2 and ultrafast photogenerated carriers of Ge. Furthermore, the "AND" and "OR" logic operations are respectively achieved at two adjacent frequency bands by weighing normalized transmission amplitude. This work may provide an auspicious paradigm of THz components, such as dynamic filters, multiband switches, and logical modulators, potentially promoting the design and implementation of multifunctional electro-optical devices in future THz computing and communication. [ABSTRACT FROM AUTHOR]

The fiber structure of three-dimensional (3D) woven preform is generally complex due to the contact interactions and micro-scale deformations of the yarns during the weaving process. The present study explores the effect of weaving parameters on the fiber architecture of 3D woven preforms. Two groups of samples were prepared and observed using micro‐computed tomography (Micro-CT) technology. Semantic segmentation of Micro-CT images was conducted using deep learning algorithm to create explicit models of different yarn systems. Two novel indicators were proposed for quantifying the changes of weft yarn position and warp/binder yarn path. This work clarifies the micro-scale deformation mechanisms of 3D woven structures. The influence of weaving parameters including weft density and weaving structure on the geometric variations of fiber structures was analyzed. The connection between weaving parameters and unit cell variations was established within the scope of this study. The conclusions of this paper would be helpful for the design of preforms with stable fiber structure. [ABSTRACT FROM AUTHOR]

The rapid human activities and urbanization exacerbate the human health risks induced by antibiotic resistance genes (ARGs). In this study, the profiling of ARGs was investigated using high-throughput qPCR from water samples of 13 catchment areas in East Tiaoxi River, China. High prevalence of ARGs indicated significant antibiotic resistance pollution in the research area (absolute abundance: 6.1 × 10 8 –2.1 × 10 10 copies/L; relative abundance: 0.033–0.158 copies/cell). Conventional water qualities (COD, TN, TP, NH 3 -N), bacterial communities and mobile gene elements (MGEs) were detected and analyzed as factors of ARGs shift. Nutrient and MGEs showed positive correlation with most ARGs ( P < 0.05) and bacteria community was identified as the key contributing factor driving ARGs alteration. With the land-use study and field investigation, country area, especially arable, was expected as a high spot for ARGs shift and pathogen breeding. Comparing to environmental background, promotion of ARGs and marked shift of bacterial community were observed in country and urban city areas, indicating that human activities may lead to the spread of ARGs. Analysis of factors affecting ARGs in this study may shed new light on the mechanism of the maintenance and propagation of ARGs in urban rivers. [ABSTRACT FROM AUTHOR]

To investigate the effect of fabric architectures and weaving parameters on thermal conductivities of three-dimensional woven composites, the 2.5D angle-interlock woven composites, 2.5D angle-interlock (with warp reinforcement) woven composites, and 3D orthogonal woven composites were prepared. The thermal conductivities of these woven composites were measured by using transient hot-wire method in this study. It was indicated that the thermal conductivities of three-dimensional woven composites showed significant differences due to the distribution of continuous fibers in three-dimensional woven composites with different structures, which could influence the sum fiber content on the cross section of heat flow. More importantly, compared with 2.5D angle-interlock woven composites and 2.5D angle-interlock (with warp reinforcement) woven composites, 3D orthogonal woven composites exhibited better performance in thermal conductivity. Overall, it was concluded that the thermal conductivities of three-dimensional woven composites were influenced by the fabric architectures and weaving parameters, such as the volume fraction, density, and types of fibers. Furthermore, the volume fraction of fibers on the cross section of heat flow was the dominant factor for thermal conductivities of different woven composites. [ABSTRACT FROM AUTHOR]

The effect of two different biochar types, rice straw biochar (RSB) and mushroom biochar (MB), on chicken manure composting was previously examined by monitoring the fate of antibiotic resistance genes (ARGs) and arsenic. The behavior of ARGs and arsenic in other kinds of manure composting with the same biochar types had not been examined. In this study, we added either RSB or MB to pig and duck manure composts to study the behavior of ARGs ( tet genes, sul genes, and chloramphenicol resistance genes) and arsenic under the same experimental condition. The results showed that the average removal values of selected ARGs were respectively 2.56 and 2.09 log units in duck and pig manure compost without the addition of biochar. The effect of biochar addition on the average removal value of ARGs depended on the type of biochar and manure. For instance, in pig manure compost, MB addition increased the average removal value of ARGs, while RSB addition decreased. And both biochar additions had a negative influence on the average removal value of ARGs in duck manure compost. Analytical results also demonstrated that MB addition reduced total arsenic and the percentage of bioavailable arsenic more than RSB. [ABSTRACT FROM AUTHOR]

• Industrial X-ray computer tomography (ICT) was used to quantify internal damage in the post-impact ultra-high molecular weight polyethylene (UHMWPE) fiber composite laminate impacted by mild steel core projectiles. • The progressive ballistic damage process of UHMWPE fiber composite laminate impacted by mild steel core projectile was elucidated. • An evaluation model of the energy absorption by UHMWPE fiber composite laminate has been established to analyze the dissipation mechanism of projectile kinetic energy. This paper presents the effect of interlaminar shear property on the ballistic response of ultra-high molecular weight polyethylene (UHMWPE) fiber composite laminate and discusses the detailed progressive ballistic damage process. Specifically, two kinds of UHMWPE fiber composite laminates with different interlaminar shear strength (ILSS) are impacted by a standard projectile (7.62 mm × 39 mm), and their multi-scale internal damage morphologies are characterized. Based on damage patterns, an evaluation model of laminate energy absorption is established to analyze the dissipation mechanism of the kinetic energy of the projectile. Results of ballistic tests indicate that the reduction of ILSS may result in the degradation of anti-penetration performance and in more serious internal damage. Internal damage morphologies show that shear fracture and delamination fracture are the primary failure modes during ballistic impact. The energy absorption by the laminate via tensile deformation, delamination failure and shear failure may account for 56.21%, 17.45%, and 16.49% of the projectile kinetic energy, respectively. Hence, tensile deformation may be the primary energy dissipation mechanism of projectile kinetic energy. [Display omitted] [ABSTRACT FROM AUTHOR]

Basic oxygen furnace slag (BOFS) has the potential to remove hexavalent chromium (Cr(VI)) from wastewater by a redox process due to the presence of minerals containing Fe 2 + . The effects of the solution pH, initial Cr(VI) concentration, BOFS dosage, BOFS particle size, and temperature on the removal of Cr(VI) was investigated in detail through batch tests. The chemical and mineral compositions of fresh and reacted BOFS were characterized using scanning electron microscope (SEM) equipped with an energy dispersive spectrometer (EDS) system and X-ray diffractometer (XRD). The results show that Cr(VI) in wastewater can be efficiently removed by Fe 2 + released from BOFS under appropriate acidic conditions. The removal of Cr(VI) by BOFS significantly depended on the parameters mentioned above. The reaction of Cr(VI) with BOFS followed the pseudo-second-order kinetic model. Fe 2 + responsible for Cr(VI) removal was primarily derived from the dissolution of FeO and Fe 3 O 4 in BOFS. When H 2 SO 4 was used to adjust the solution acidity, gypsum (CaSO 4 ·2H 2 O) could be formed and become an armoring precipitate layer on the BOFS surface, hindering the release of Fe 2 + and the removal of Cr(VI). Finally, the main mechanism of Cr(VI) removal by BOFS was described using several consecutive reaction steps. [ABSTRACT FROM AUTHOR]

In this study, the occurrence of 8 antibiotics [3 tetracyclines (TCs), 4 sulfonamides, and 1 trimethoprim (TMP)], 12 antibiotic resistance genes (ARGs) (10 tet, 2 sul), 4 types of bacteria [no antibiotics, anti-TC, anti-sulfamethoxazole (SMX), and anti-double], and intI1 in two wastewater treatment plants (WWTPs) were assessed and their influences in downstream lake were investigated. Both WWTPs' effluent demonstrated some similarities, but the abundance and removal rate varied significantly. Results revealed that biological treatment mainly removed antibiotics and ARGs, whereas physical techniques were found to eliminate antibiotic resistance bacteria (ARBs) abundance (about 1 log for each one). UV disinfection did not significantly enhance the removal efficiency, and the release of the abundantly available target contaminants from the excess sludge may pose threats to human and the environment. Different antibiotics showed diverse influences on the downstream lake, and the concentrations of sulfamethazine (SM2) and SMX were observed to increase enormously. The total ARG abundance ascended about 0.1 log and some ARGs (e.g., tetC, intI1, tetA) increased due to the high input of the effluent. In addition, the abundance of ARB variation in the lake also changed, but the abundance of four types of bacteria remained stable in the downstream sampling sites. [ABSTRACT FROM AUTHOR]

In this study, we developed a molding process for a new type of z-pin applicable to C/C composites. Polyvinyl alcohol (PVA) was adopted as the matrix of z-pins because it has few solid residues when subjected to an inert high-temperature environment. A highly concentrated PVA aqueous solution was prepared to impregnate the carbon fiber bundle. The draw forming method from small-hole-cavity dies was used to mold the PVA-matrix z-pins. Four z-pins with different resin content were made by four dies with the cavity diameters of 0.50, 0.60, 0.70 and 0.80 mm, respectively. The piercing processes and properties of the z-pins were analyzed by piercing them into carbon fiber laminated fabrics. The results showed that the measured value of the PVA resin volume content of the z-pins was slightly larger than the theoretical value. And the z-pin prepared in the molding die with a cavity diameter of 0.70 mm (P7) exhibited the best piercing property with a resin volume content of 45.6%. The maximum compressive stress in the whole piercing process of P7 was the lowest as compared to the z-pins molded by the other dies, and little damage to the piercing tip of P7 was observed after the penetration. In addition, the z-pins can fully pierce laminated fabrics with a thickness of 9 mm. [ABSTRACT FROM AUTHOR]

The aim of this study executed on Silicon Nitride (Si3N4) yarn is to examine some bending damage behaviors and fracture mechanisms that occur during the 3D orthogonal fabric forming process. A three point bending experiment device has been developed in order to simulate the Z-binder yarn bending condition. The effects of weft density, fabric thickness, and yarn tension have been studied. The Weibull analysis of the tensile strength show that the bending damage increases with the increase of weft density, fabric thickness, and yarn tension. The resulting bending damage causes a reduction in yarn strength of between 2.5 and 17.2% depending on the bending parameters of yarn. The growth of the fibrillation area also reflects similar trends with tensile strength loss rate. The fibrillation length produced by the yarns is mostly distributed within the range of 0.3 to 0.9 mm. A comparison of the calculation result to experimental data shows the bending fracture probability of filaments inside yarn are less than that of monofilament. The tensile and bending fracture of Si3N4 filaments exhibit typical brittle fracture characteristics. [ABSTRACT FROM AUTHOR]