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Two-dimensional layered materials commonly face hindered electron transfer and poor structure stability, thus limiting their application in high-rate and long-term sodium ion batteries. In the current study, we adopt finite element simulation to guide the rational design of nanostructures. By calculating the von Mises stress distribution of a series of carbon materials, we find that the hollow biconcave structure could effectively alleviate the stress concentration resulting from expansion. Accordingly, we propose a biconcave-alleviated strategy based on the Aspergillus niger-derived carbon (ANDC) to construct ANDC/MoS2 with a hollow biconcave structure. The ANDC/MoS2 is endowed with an excellent long-term cyclability as an anode of sodium ion batteries, delivering a discharge capacity of 496 mAh g-1 after 1000 cycles at 1 A g-1. A capacity retention rate of 94.5% is achieved, an increase of almost seven times compared with the bare MoS2 nanosheets. Even at a high current density of 5 A g-1, a reversible discharge capacity around 400 mAh g-1 is maintained after 300 cycles. ANDC/MoS2 could also be used for efficient lithium storage. By using in situ TEM, we further reveal that the hollow biconcave structure of ANDC/MoS2 has enabled stable and fast sodiation/desodiation.

The hybrid tracked vehicles(HTV) usually adopt series hybrid powertrain with extra steering mechanism, which has relatively low transmission efficiency and reduces the flexibility of structural arrangement. To overcome the disadvantages, a new kind of single-mode powertrain has been proposed. The power-split hybrid powertrain is composed of three planetary gear (PG) sets connected to one engine, left and right track outputs, and three motors. The proposed powertrain can realize steering while going forward by controlling the output torque on each side without extra steering mechanism or steering shaft. Due to the diversity of the connection way between components and planetary gear sets, a rapid configuration design approach is proposed for the design selection of HTV. The automated dynamic modelling method can show the one-to-one correspondence with the selected feasible groups by establishing two characteristic matrices, which is more simple than other researches. The analytically-based method is proposed to classify all possible connection designs into several groups to decrease the searching scope with improved design efficiency. Finally, the optimal control strategy is used to find the design with optimal fuel economy under typical condition of HTV. The case study is implemented by the proposed design approach which demonstrates better design performances compared with the existing series-hybrid HTV.

To protect the underlying soil and groundwater from landfills, the landfills are commonly lined with layered liner systems. Geosynthetic clay liners (GCL) have been increasingly used in the landfill liner systems to substitude the traditional compacted clay liners (CCL) because of their low cost, easily construction behavior and low leakage rate. To study the behavior of the GM+GCL liner system used in China due to the migration of Pb2+, we introduce in detail GM+GCL liner systems proposed by the Chinese specification. Then one dimensional finite layer model is used to investigate the anti-pollution behavior of the CM+GCL composite liner systems, with the focuses on the heavy metal Pb2+. It could be concluded that the main migration way through the GM+GCL composite liner system is that the transport of Pb2+through a GM+GCL composite liner system of a landfill cover takes place primarily through the holes in the GM. The findings provide useful reference for preventing, controlling and treating groundwater pollution in the GM+GCL liner system technically and scientifically.

An analytical model is established to predict the seepage performance of the liner system composed of a compacted clay liner (CCL) covered by a geomembrane (GM). The contaminant of Pb2+diffusing through the geomembrane is assumed to be a steady-state process. The liner systems with low leakage performance are usually utilized in the municipal solid waste landfills to prevent the contaminants of the leachate from polluting the groundwater and soil beneath the landfill. To investigate the seepage rate of the Pb2+in the liner systems of the landfill considering the effects of the geomembrance, the influence of the geomembrance on the seepage performance of the liner system is studied. Parametric analyses are conducted to study the effects of the thickness of GM and the number of defects in the GM on the leakage performance of the liner system. In conclusion, some suggestions for the design of the municipal solid waste landfills are proposed based on the analyses results.

The cushion systems with low leakage performance are usually utilized in the municipal solid waste landfills to prevent the contaminants of the leachate from polluting the groundwater and soil beneath the landfill. Even there are the rigorous demands in related specifications in China and other countries all over the world for the design of the cushion system in the landfill. Pollution of the groundwater and the soil beneath the landfill still occurred in a large number of rubbish landfills because of the seepage. To investigate the seepage rate of the Cd2+ in the cushion systems, the minimum requirements for the design of the cushion systems are summarized according to the provisions of China and US. Comparative studies using 1-dimensional migration model are performed to investigate the seepage performance of the cushion systems consisting of geomembrance (GM) and compacted clay layer (CCL) sastifying the related minimum design demands. It could be concluded that the cushion system designed according to the minimum demands of China provide better anti-leakage performance, while that of US perform the lower. Finally, some advices for the releavent design standards are suggested according to the analyses.

The pollutants in the municipal solid waste landfill leachate result in severe damage to the environment of the groundwater and the soil beneath the municipal solid waste landfill. The liner systems with a low leakage performance are commonlly adopted under the municipal solid waste landfills to stop the contaminants of the leachate from polluting the environment. Even there are the rigorous demands in related specifications for the design of the liner system in the landfill. Pollution of the groundwater and the soil beneath the landfill still occurred in a large number of rubbish landfills because of the seepage. To investigate the influence of the compact clay layer (CCL) on the seepage performance of the liner systems, parametric analyses are conducted to study the influence of the thickness of CCL and the hydraulic conductivity of CCL on the leakage performance of the liner system. In conclusion, some suggestions for the design of the municipal solid waste landfills are proposed based on the analyses results.

The Shanxi and Taiyuan formations in Permo-Carboniferous of upper Paleozoic Erathem of Qinshui Basin, not only has abundant coal and CBM resources, also has a lot of shales. By analyzing the shale thickness, organic matter type, organic matter abundance, vitrinite reflectance, mineral composition of the Permo-Carboniferous coal-bearing strata, considered that the shale thickness of coal-bearing strata in the Qinshui Basin is larger, the organic matter abundance is general, but maturity is high and full of rich brittle mineral. It is in favor of late fracturing.

Based on the coal reservoirs geological feature and coalbed methane (CBM) wells production data, and taken FS-2 well in the southern Junggar Basin as examples, history matching and productivity prediction of FS-2 well were conducted by using COMET3 numerical modeling software and the influence factors sensitivity of gas well productivity in the study area were analyzed. The results suggest: FS-2 well total gas production in the eight years was 2915007 m3, and the average daily gas production reached 1209.5m3/d, the CBM well belongs to medium production well. Permeability and gas content has the most effect on the single wells production in the study area, so the influence of the fracture half-length and coal seam thickness is weakened.

Applying the method of source rocks pyrolysis to analyze 19 pieces of coal measure source rocks of Shanxi-Taiyuan group in Huanghua Depression, the results show that the level of organic matter abundance of coal measures hydrocarbon source rock in Shanxi-Taiyuan group of Well Wanggu 1 is the poor. Using monadic linear regression method to analysis the data of S2 and TOC, the results show that the type of the mudstone organic matter in the Shanxi - Taiyuan group belongs to III, the type of coal sample organic matter in Shanxi-Taiyuan group belongs to I. Due to the data of samples in the Shanxi group is less, the results of the coal sample in Shanxi group are only for reference. According to the data of Tmax, the most of the coal measures hydrocarbon source rocks in Shanxi - Taiyuan group are in the maturity stage, several samples are in the high maturity stage.

Using data analysis and comparative analysis, the distribution of Coalbed methane (CBM) gas content in southern Junggar were analyzed on the basis of the southern Junggar Basin coalfield geological data, and the main controlling factors of CBM accumulation were studied. The results show that, Gas content ranges from 2cm3/g to 15cm3/g, which overall is highest in central and eastern and becomes progressively smaller in trend of westward. The study area has many characteristics, such as Multi-seam, large coal seam thickness, mainly Fine-grained clastic rock, which is conducive to the enrichment of the CBM. Study area belongs to confined aquifer of low water-richness and receives the supply of atmospheric precipitation and river. In the coal seams within a certain depth formed Runoff water and the CBM diffusion pattern of desorption - diffusion - transport - water soluble gas runoff, which are not conducive to the enrichment of the CBM.

The objective of this study is to analyze the crash frequency by collision type at freeway diverge areas. Three major collision types were identified in this study including rear-end, sideswipe and angle collisions. We compared the crash counts and crash rates by collision type between exit ramp. The data analysis results show that exit ramps with lane-balance design have lower crash frequency and crash rate of rear-end collisions than those not lane-balanced.

During the last decades, especially the Eleventh Five-Year Plan period, China vocational education on environmental protection has made remarkable progresses. The vocational education on environmental protection has developed fast and spread widely, and formed an integrity system with various kinds of types. On the basis of analyzing the development status of vocational education in the field of China environmental protection and the cooperative mechanism and operative mode of production, teaching, research and application of partial higher vocational environmental education and environmental majors at home, this paper describes the history and development of vocational education on environmental protection in China and conducted a case study of vocational education on Changsha Environmental Protection Vocational College (CEPVC). The purpose is to identify lessons from past experience in vocational education to inform future development. The retrospective nature of this paper focuses attention on what has been done in the past, and to a lesser extent on the nature of current state. There are significant issues in vocational education, for example, the contribution of training to informal sector employment, that fall largely outside of vocational education experience, this is important for the future.

With the rapid development of science and technology, we could enjoy more and more convenience of modern technology, we have to face the negative influence of modern technology on environment. The Kitakyushu city used to be one of most heavily air-polluted regions in Japan. Through decades of improvement on the environmental education, the Kitakyushu city become the ‘Demonstration city on environment protect of Japan’ and the ‘Typical city of environmental governance’ award by the United Nation. These effective measures include increasing the investment in the environmental education and scientific research, extensively conducting environmental education to improve the public awareness of environmental protection and promoting the integration and transformation of production, knowledge and research on environmental protection. This paper studied the main steps that the Kitakyushu city take to improve its environment pollution and analyze the revelation of these useful measures to China’s environmental education.