Search

Climate change is becoming an important issue in all fields of infrastructure development. Electricity plays a core role in the decarbonized energy system’s path to a regional zero-emission pattern. A well-built trans-Mediterranean backbone grid can hedge the profound evolution of regional power generation, transmission, and consumption. To date, only Turkey and the Maghreb countries (i.e., Morocco, Algeria, and Tunisia) are connected with the Continental European Synchronous Area. Other south- and east-shore countries have insufficient interconnection infrastructures and synchronization difficulties that have proven to be major hurdles to the implementation of large-scale solar and wind projects and achievement of climate goals. This study analyzes the current trans-boundary grid interconnections and power and carbon emission portfolios in the Mediterranean region. To align with the recently launched new climate target ‘Fit for 55’ program and the accelerated large-scale renewables target, a holistic review of projected trans-Mediterranean grids and their market, technical, and financial obstacles of implementation was conducted. For south- and east-shore countries, major legal and regulatory barriers encompassing non-liberalized market structure, regulation gaps of taxation and transmission tariffs, and the private sector’s access rights need to be removed. Enhancement of domestic grids, substations, and harmonized grid codes and frequency, voltage, and communication technology standards among all trans- Mediterranean countries are physical prerequisites for implementing the Trans-Mediterranean Electricity Market. In addition, the mobilization of capital instruments along with private and international investments is indispensable for the realization of supranational transmission projects. As the final section of the decarbonization roadmap, the development of electric appliances, equipment, and vehicles with higher efficiency is inevitable in the decarbonized building, transportation, and industry sectors.

With the rapid development of 5G technology, low dielectric constant materials present a widespread application prospect in microelectronic devices. Poly (aryl ether) resins have been widely used in this field due to their excellent thermal stability, mechanical properties and electrical insulation properties, however, reducing its dielectric constant remains a challenge. In this study, novel phenolphthalein poly (aryl ether ketone) containing isopropyl groups and fluorene groups was successfully synthesized with high molecular weight via SN2 aromatic nucleophilic polycondensation reaction. At lower frequencies ranging from 10 Hz to 1 MHz and higher frequencies from 10 GHz to 42 GHz, the films exhibit the intrinsic dielectric constant in the range of 2.4–2.7. The resin has good thermal stability, mechanical properties and insulation properties. Thus, the functional poly (aryl ether ketone) possesses attractive potential applications in the field of high-performance flexible electronic packaging materials.

Antibiotic resistance genes (ARGs) have been widely found and studied in soil and water environments. However, the propagation of ARGs in plant microbiomes has attracted insufficient attention. Plant microbiomes, especially the rhizosphere microorganisms, are closely connected with water, soil, and air, which allows ARGs to spread widely in ecosystems and pose a threat to human health after entering the human body with bacteria. Therefore, it is necessary to deeply understand and explore the dynamics and the transmission of ARGs in rhizosphere microorganisms and endophytes of plants. In this review, the transmission and influencing factors of ARGs in the microorganisms associated with plants, especially the influence of root exudates on plant microbiomes, are analyzed. Notably, the role of intrinsic genes of plants in determining root exudates and their potential effects on ARGs are proposed and analyzed. The important role of phyllosphere microorganisms and endophytes in the transmission of ARGs and co-resistance of antibiotics and other substances are also emphasized. The proliferation and transmission of ARGs associated with plant microbiomes addressed in this review is conducive to revealing the fate of ARGs in plant microorganisms and alleviating ARG pollution.

Abstract The cryogenic process has been widely applied in various fields, but it has rarely been reported in the preparation of anode materials for lithium-ion battery. In this paper, activated carbon derived from hemp stems was prepared by carbonization and activation; then, it was subjected to cryogenic treatment to obtain cryogenic activated carbon. The characterization results show that the cryogenic activated carbon (CAC) has a richer pore structure than the activated carbon (AC) without cryogenic treatment, and its specific surface area is 1727.96 m2/g. The porous carbon had an excellent reversible capacity of 756.8 mAh/g after 100 cycles at 0.2 C as anode of lithium-ion battery, in which the electrochemical performance of CAC was remarkably improved due to its good pore structure. This provides a new idea for the preparation of anode materials for high-capacity lithium-ion batteries.

Abstract As a biomass waste, hemp stems have the advantages of low cost and abundance, and it is regarded as a promising anode material with a high specific capacity. In this paper, activated carbon derived from hemp stems is prepared by low-temperature carbonization and high-temperature activation. The results of characterizations show the activated carbon has more pores due to the advantages of natural porous structure of hemp stem. The aperture size is mainly microporous, and there are mesopores and macropores in the porous carbon. The porous carbon has an excellent reversible capacity of 495 mAh/g after 100 cycles at 0.2 °C as the anode of lithium-ion battery. Compared with the graphite electrode, the electrochemical property of activated carbon is significantly improved due to the reasonable distribution of pore size. The preparation of the activated carbon provides a new idea for low cost and rapid preparation of anode materials for high capacity lithium-ion batteries.

Traffic flow prediction is the foundation of many applications in smart cities, and the granular precision of traffic flow prediction has to be enhanced with refined applications. However, most of the existing researches cannot meet these requirements. In this paper, we propose a spatial-temporal attention based fusion network (ST-AFN), for lane-level precise prediction. This seq2seq model consists of three parts, namely speed process network, spatial encoder, and temporal decoder. In order to exploit the dynamic dependencies among lanes, attention mechanism blocks are embedded in those networks. The application of deep spatial-temporal information matrix results in progresses in term of reliability. Furthermore, a specific ground lane selection method is also proposed to ST-AFN. To evaluate the proposed model, four months of real-world traffic data are collected in Xiaoshan District, Hangzhou, China. Experimental results demonstrate that ST-AFN can achieve more accurate and stable results than the benchmark models. To the best of our knowledge, this is the first time that a deep learning method has been applied to forecast traffic flow at the lane level on urban ground roads instead of expressways or elevated roads.

With the continuous development of smart cities, intelligent transportation systems (ITSs) have ushered in many breakthroughs and upgrades. As a solid foundation for an ITS, traffic flow prediction effectively helps the city to better manage intricate traffic flow. However, existing traffic flow prediction methods such as temporal graph convolutional networks(T-GCNs) ignore the dissimilarities between lanes. Thus, they cannot provide more specific information regarding predictions such as dynamic changes in traffic flow direction and deeper lane relationships. With the upgrading of intersection sensors, more and more intersection lanes are equipped with intersection sensors to detect vehicle information all day long. These spatio-temporal data help researchers refine the focus of traffic prediction research down to the lane level. More accurate and detailed data mean that it is more difficult to mine the spatio-temporal correlations between data, and modeling heterogeneous data becomes more challenging. In order to deal with these problems, we propose a heterogeneous graph convolution model based on dynamic graph generation. The model consists of three components. The internal graph convolution network captures the real-time spatial dependency between lanes in terms of generated dynamic graphs. The external heterogeneous data fusion network comprehensively considers other parameters such as lane speed, lane occupancy, and weather conditions. The codec neural network utilizes a temporal attention mechanism to capture the deep temporal dependency. We test the performance of this model based on two real-world datasets, and extensive comparative experiments indicate that the proposed heterogeneous graph convolution model can improve the prediction accuracy.

Aiming at the flexible 3D stretch bending with multipoint dies for the aluminum profile, the numerical simulation analysis of the bending process was carried out by ABAQUS finite element software. In the multipoint stretch bending (MPSB) process, the influence of the number of die units on the springback for the complex section profile was studied. The shape error between the forming parts and the target parts was reduced through the method of die surface modification. The results showed that the springback of the aluminum profile could reach a minimum when the number of die units was 25 under the precondition of saving cost and ensuring the quality of forming parts. In the numerical simulation, the maximum shape error of the forming parts reduced from 18.824 mm to 2.456 mm; in the test, the maximum shape error reduced from 27.26 mm to 6.03 mm through the method of die surface modification.

BackgroundEffects of extreme sleep duration on risk of mortality and cardiovascular outcomes remain controversial. We aimed to quantify the dose‐response relationships of sleep duration with risk of all‐cause mortality, total cardiovascular disease, coronary heart disease, and stroke. Methods and ResultsPubMed and Embase were systematically searched for prospective cohort studies published before December 1, 2016, that examined the associations between sleep duration and at least 1 of the 4 outcomes in generally healthy populations. U‐shaped associations were indicated between sleep duration and risk of all outcomes, with the lowest risk observed for ≈7‐hour sleep duration per day, which was varied little by sex. For all‐cause mortality, when sleep duration was 7 hours per day, the pooled RR was 1.13 (95% CI, 1.11–1.15) per 1‐hour increment. For total cardiovascular disease, the pooled RR was 1.06 (95% CI, 1.03–1.08) per 1‐hour reduction and 1.12 (95% CI, 1.08–1.16) per 1‐hour increment of sleep duration. For coronary heart disease, the pooled RR was 1.07 (95% CI, 1.03–1.12) per 1‐hour reduction and 1.05 (95% CI, 1.00–1.10) per 1‐hour increment of sleep duration. For stroke, the pooled RR was 1.05 (95% CI, 1.01–1.09) per 1‐hour reduction and 1.18 (95% CI, 1.14–1.21) per 1‐hour increment of sleep duration. ConclusionsOur findings indicate that both short and long sleep duration is associated with an increased risk of all‐cause mortality and cardiovascular events.

In this study, we adopted a novel method to synthesize a rice husk-derived carbon@SnO _2 @reduced graphene oxide (rGO)composite with a multi-level structure as an anode electrode for lithium-ion batteries. The carbon source of composite was cellulose extracted from RH. The material exhibits excellent performance of LIBs with large reversible capacity and outstanding cycle performance. It shows a reversible capacity of 1206.9 mAhg ^−1 at a current density of 0.2C after 100 cycles. Excellent cycle performance is due to unique multi-level structure, which increases active site of lithium ion. Furthermore, SnO _2 nanoparticles (SnO _2 NPs) and carbon skeleton have strong chemical bonds to prevent SnO _2 NPs from falling out of the three-dimensional network during cycling., thereby making material a promising anode material for LIBs.

As a most attractive renewable resource, biomass has the advantages of low pollution, wide distribution and abundant resources, promoting its applications in lithium ion batteries (LIBs). Herein, cellulose-derived carbon nanospheres (CCS) were successfully synthesized by hydrothermal carbonization (HTC) from corn straw for use as an anode in LIBs. The uniform distribution and cross-linked structure of carbon nanospheres were obtained by carefully controlling reaction time, which could not only decrease the transport pathway of lithium ions, but also reduce the structural damage caused by the intercalation of lithium ions. Especially, obtained after hydrothermal carbonization for 36 h, those typical characteristics make it deliver excellent cycling stability as well as the notable specific capacity of 577 mA h g−1 after 100 cycles at 0.2C. Hence, this efficient and environment-friendly method for the fabrication of CCS from corn straw could realize the secondary utilization of biomass waste, as well as serve as a new choice for LIBs anode materials.

Nanostructured TiO2 was successfully synthesized via a facile one-pot solvothermal reaction followed by calcina‐ tion. Hydrolysis and polycondensation of titanium butox‐ ide (Ti(OR)4) were performed in the presence of sodium dodecylbenzenesulfonate (SDBS). The morphologies, crystallinity and compositions of obtained samples were identified by the methods of X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) and transmission electron microscopy (TEM). It was found that the nanostructured TiO2 with an average diameter of 10±5 nm had the crystal type of anatase. A good specific surface was also obtained by the standard multipoint BET method (119.2 m2/g). As the anode materials for the lithium-ion batteries (LIBs), the anatase phase TiO2 demonstrated a relatively high gravi‐ metric specific capacity of 264.8 mAh g-1. The reversible capacity of TiO2 remained 196.4 mAh g-1 at a rate of 0.2 ̊C after 100 cycles. It indicated that this kind of TiO2 possessed a good electrochemical performance.

Composites with good thermomechanical and UV-shielding properties are essential in fiber-reinforced composites. This paper focuses on composites' ultraviolet (UV) shielding efficiency with added Ce-Zr-Si oxide nanoparticles/epoxy resin. The Ce-Zr oxide nanoparticles were first functionalized with a silicon coupling agent and ethyl silicate to improve their dispersion and surface activity. In this work, we prepared epoxy nanocomposites with the addition of Ce-Zr -Si oxides(1,3,5,7 wt%) and found that the materials had good enhancement of the UV shielding properties of the epoxy resin matrix. Meanwhile, it was used in basalt fiber (BF)/epoxy composites prepared by the hot-pressing method, and surface treatment of basalt fibers was carried out. The results showed that the modified fiber composites could effectively enhance the thermomechanical properties of epoxy resin composites. It is noteworthy that the tensile strength and flexural strength of the hybrid composites reached their peak when 5 wt% Ce-Zr-Si was added, increasing by 13.8% and 33.67% respectively. The modified (BF)/epoxy composites exhibited improved thermal stability compared to pure epoxy resin, with the maximum weight loss temperature of BF-1/EP reaching 349°C. The T(UVA) decreased to 2.41%, while the T(UVB) decreased to 0.053%, and almost all the ultraviolet irradiation was blocked. These results show that our prepared composites have good thermomechanical and UV shielding properties. Highlights • Ce-Zr oxide nanoparticles were functionalized with a silicon coupling agent. • Ce-Zr-Si oxide was added to enhance the ultraviolet shielding efficiency. • Modified BFs were composited to improve thermomechanical properties. [ABSTRACT FROM AUTHOR]