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AbstractIn recent years, with the higher requirements for the performance of cement-based materials and the call for energy conservation and environmental protection, a wave of research on new materials has set off, and various high-performance concrete and more environmentally friendly geopolymers have appeared in the public. With a view to solving the defects of energy consumption, environmental protection and low toughness of traditional cement-based materials. At the same time, nanomaterials have become a focus of current research. Therefore, the research on the properties of cement-based materials and geopolymers modified by graphene and its derivatives has aroused extensive interest of researchers. Graphene-based nanomaterials are one of them. Because of their large specific surface area, excellent physical properties have been favored by many researchers. This paper reviews the research progress of graphene-based nanomaterials in improving the properties of cement-based materials and geopolymer materials, and points out the main challenges and development prospects of such materials in the construction field in the future.

Microorganisms are essential for the formation of biogenic coalbed methane (CBM) and the application of microbially enhanced CBM (MECoM). Anthracite-degrading methanogenic microflora was cultivated by enrichment and subculture from produced water obtained in Qinshui Basin where CBM is explored commercially. The maximum methane yield was 255 μmol/g of coal after 23 days of cultivation at 35 °C, 1.1–1.2% of salinity, <0.15 mm of coal particle size, pH 8–9, and 5 mL of inocula/g of coal. Microflora archaea, as revealed by MiSeq, were mainly composed of Methanosaeta, an acetic acid-consuming methanogen, followed by Methanocella, a hydrogen-consuming methanogen, suggesting a diversity of methanogenic pathways with a dominance of acetoclastic methanogenesis. The bacteria mainly included Enterobacter, Acetoanaerobium, Macellibacteroides, Clostridium, and Ercella. FTIR analysis showed that the oxygen-containing groups and aliphatic groups were the main targets for microbial degradation. XRD analysis indicated that crystal nucleus structures of coal decreased after degradation. The concentrations of aliphatics were shown to increase over the incubation period based on GC–MS analysis, while the concentrations of dissolved aromatics decreased. These results show the potential for enhancing CBM production by stimulating the activity of methanogenic consortia in situ in Qinshui Basin as well as other high-rank coal reservoirs.

China is the world’s largest emitter of CO2. As the largest sector of China’s fossil energy consumption and carbon emissions, manufacturing plays an important role in achieving emission reduction targets in China. Using the extended logarithmic mean division index (LMDI) decomposition model, this paper decomposed the factors that affect the CO2 emissions of China’s manufacturing industry into eight effects. The results show the following: (1) China’s manufacturing CO2 emissions increased from 1.91 billion tons in 1995 to 6.25 billion tons in 2015, with an average annual growth rate of 6%. Ferrous metal smelting and rolling were the largest sources of carbon dioxide emissions, followed by chemical raw materials and products and then non-metallic minerals. (2) During the research period, the industrial activity effects were the most important factor leading to increased CO2 emissions in manufacturing and energy intensity was the most important factor in promoting the reduction of CO2 emissions from manufacturing. The investment intensity was the second most influential factor leading to the increase in China’s manufacturing CO2 emissions after the industrial scale and this even exceeded the industrial activity effect in some time periods (2000–2005). R&D efficiency and R&D intensity were shown to have significant roles in reducing CO2 emissions in China’s manufacturing industry. The input of R&D innovation factors is an effective way to achieve emission reductions in China’s manufacturing industry. (3) There were differences in the driving factors of CO2 emissions in the manufacturing industry in different periods that were closely related to the international and domestic economic development environment and the relevant policies of the Chinese government regarding energy conservation and emission reduction. (4) Sub-sector research found that the factors that affect the reduction of CO2 emissions in various industries appear to be differentiated. This paper has important policy significance to allow the Chinese government to implement effective energy-saving and emission reduction measures and to reduce CO2 emissions from the manufacturing industry.

Fully integrated nanodevices that allow the complete functional implementation without an external accessory or equipment are deemed to be one of the most ideal and ultimate goals for modern nanodevice design and construction. In this work, we demonstrate the first example of a bendable biofuel cell (BFC)-based fully integrated biomedical nanodevice with simple, palm-sized, easy-to-carry, pump-free, cost-saving, and easy-to-use features for the point-of-care (POC) diagnosis of scurvy from a single drop of untreated human serum (down to 0.2 μL) by integrating a bendable and disposable vitamin C/air microfluidic BFC (micro-BFC) (named iezCard) for self-powered vitamin C biosensing with a custom mini digital LED voltmeter (named iezBox) for signal processing and transmission, along with a ″built-in″ biocomputing BUFFER gate for intelligent diagnosis. Under the simplicity- and practicability-oriented idea, a cost-effective strategy (e.g., biomass-derived hierarchical micro–mesoporous carbon aerogels, screen-printed technique, a single piece of Kimwipes paper, LED display, and universal components) was implemented for nanodevice design rather than any top-end or pricey method (e.g., photolithography/electron-beam evaporation, peristaltic pump, wireless system, and 3D printing technique), which enormously reduces the cost of feedstock down to ∼USD 2.55 per integrated kit including a disposal iezCard (∼USD 0.08 per test) and a reusable iezBox (∼USD 2.47 for large-scale tests). These distinctive and attractive features allow such a fully integrated biomedical nanodevice to fully satisfy the basic requirements for POC diagnosis of scurvy from a single drop of raw human serum and make it particularly appropriate for resource-poor settings, where there is a lack of medical facilities, funds, and qualified personnel.