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To clarify the evolution of thermal maturity and pore structure in continental organic-rich shales, calcareous shales of the Liaohe Basin (China) were pyrolyzed, and examined using Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), nitrogen sorption isotherms, and nuclear magnetic resonance (NMR) spectroscopy. The increase in Raman G-D band separation and decrease in Raman ID/IG ratio with increasing thermal maturity indicate that these parameters provide superior thermal maturity indicators. This is also confirmed by the good linear correlation of G-D band shifts and ID/IG with vitrinite reflectance (VR) and maximum temperature (Tmax), respectively. The relative detection accuracy (DA), sampling requirements (SR), sample preparation (SP), detection time (DT), and equipment requirement (ER) of VR, G-D band shifts, ID/IG, Tmax, FTIR, and XPS indicate that Raman analysis is a simple, quick, and robust method to evaluate thermal maturity. The moderate SR, complex SP, and long DT suggest that VR and Tmax are less widely applicable for characterizing thermal maturity. The FTIR and XPS techniques provide semi-quantitative maturity indicators with poor DA and high ER. Pores observed within organic matter and minerals under SEM indicate that an increase in thermal maturity not only affects the development of organic pores but is also beneficial for the formation of mineral dissolution pores, such as those formed during the transformation of Na0 95Ca016Al1 16Si2 84O8 to Na0 84Ca0 02Al1 02Si2 98O8, a process confirmed by XRD. The BET and NMR data also indicate that the development of pore structure is closely related to the evolution of thermal maturity in calcareous shale . During the initial stage, primary pores are filled by bitumen generated from kerogen; this leads to a decrease in transition pores, mesopores, and shale porosity, and reduced pore connectivity. Then, secondary nanoscale pores, transition pores, and mesopores increase with increasing thermal maturity. The peak in secondary porosity is consistent with the liquid hydrocarbon production rate peak, a process that increases shale porosity and leads to improved pore connectivity. The dissolution of minerals induced by organic acids may also contribute to this secondary porosity. With a further increase in thermal maturity, secondary porosity at the microscale is further developed, while transition pores and mesopores collapse, resulting in reduced pore connectivity. The poor pore connectivity that occurs at both low and high VR values may be more conducive to the preservation of shale oil and gas. This study is significant for research into the evolution of thermal maturity and pore structure in continental organic-rich shales. [ABSTRACT FROM AUTHOR]

Polyaniline (PANI) has long been explored as a promising organic cathode for Li-ion batteries. However, its poor electrochemical utilization and cycling instability cast doubt on its potential for practical applications. In this work, we revisit the electrochemical performance of PANI in nonaqueous electrolytes, and reveal an unprecedented reversible capacity of 197.2 mAh g−1 (244.8 F g−1) when cycled in a wide potential range of 1.5 to 4.4 V vs. Li+/Li. This ultra-high capacity derives from 70% -NH- transformed to =NH+- during deep charging/discharging process. This material also demonstrates a high average coulombic efficiency of 98%, an excellent rate performance with 73.5 mAh g−1 at 1800 mA g−1, and retains 76% of initial value after 100 cycles, which are among the best reported values for PANI electrodes in battery applications. [ABSTRACT FROM AUTHOR]

Vaccines are one of the most effective means of preventing influenza A, typically containing the hemagglutinin (HA) of the influenza A virus. However, antigenic drift and shift of the influenza A virus can lead to instability in vaccine efficacy. Compared to HA, the antigenic variation rate of neuraminidase (NA) is slower. In traditional inactivated influenza vaccines, although they contain a certain amount of NA, there are significant differences between different batches, which cannot consistently induce NA-based immune responses. Therefore, NA is often overlooked in vaccine development. In this study, we report an mRNA vaccine encoding the NA of two strains of influenza A virus. The experimental results demonstrated that when matched with the viral strain, this mRNA vaccine induced high levels of neutralizing antibodies, providing a protective effect to mice in viral challenge experiments, and this immune response was shown to be biased towards the Th1 type. In summary, this study demonstrates that NA is a promising potential antigen, providing new insights for the development of influenza A virus vaccines. [ABSTRACT FROM AUTHOR]

Porous carbons (PCs) have been widely investigated as electrode materials for supercapacitors. However, during the preparation process, intense pore formation reactions result in an amorphous carbon structure, which limits the rate performance of the electrode material. Herein, coal is chosen as a carbon source and making use of different reaction characteristics of vitrinite and inertinite with a KOH activator, an interconnected porous structure carbon material with an abundant graphite microcrystalline structure is obtained; the organic relationships between the ratio of vitrinite and inertinite, carbonization conditions, material structure and capacity performance were researched. At the ratio of vitrinite to inertinite of 1 : 2, the sample shows a specific surface area of 2507 m2 g−1 and its ID1/IG is 1.31, which is lower than that of raw coal (1.36). Due to the synergistic effect of the pore structure and graphite microcrystals, PC-900-40 exhibits an improved specific capacitance of 229.40 F g−1 at a current density of 1.0 A g−1, and even at a high current density of 10.0 A g−1 it delivers a specific capacitance of 170.04 F g−1. The PC-900-40//PC-900-40 symmetrical capacitor retains 96% of its initial capacitance after 20 000 cycles. [ABSTRACT FROM AUTHOR]

While biochar and manure can provide considerable benefits to soil properties, how these amendments may alter soil microbial activity and decomposition processes remains unknown. In a split‐split‐split‐plot experiment, we amended a sandy loam soil with three rates of manure (whole plot; 0, 3, 9 Mg ha−1) and biochar (split‐plot; 0, 2.5, 10 Mg ha−1), and installed three species of wood stakes (split‐split‐split plot; triploid poplar, Populus tomentosa Carr.; trembling aspen, Populus tremuloides Michx.; and loblolly pine, Pinus taeda L.) on the soil surface and in the mineral soil (split‐split plot) to serve as a substrate for microbial degradation. Wood stakes were sampled 3 years after installation to assess decomposition rates (mass loss), and changes in wood carbon (C) and nitrogen (N). In addition, soil extracellular enzyme activities at the 0–20 cm depth were examined. Biochar alone, especially 10 Mg ha−1, increased wood stake decomposition and moisture content on the soil surface and in the mineral soil. Manure at the rate of 9 Mg ha−1 increased soil N‐acetyl‐β‐D‐glucosaminidase, α‐glucosidase, and aryl sulfatase activities by 91%, 17%, and 48% respectively. Because of the synergistic benefits of biochar and manure, we suggest that, in this climatic regime and soil texture, 10 Mg ha−1 biochar can be used for soil C sequestration and soil quality improvement, and 9 Mg ha−1 manure can be used in combination with biochar to build soil organic matter in plantations. [ABSTRACT FROM AUTHOR]