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Ultramicroporous carbon materials with uniform pore size accurately adjusted to the dimension of electrolyte ions or CO2 molecule are highly desirable for maximizing specific capacitance and CO2 uptake. However, efficient ways to fine‐tuning ultramicropore size at angstrom level are scarce. A completely new approach to precisely tuning carbon ultramicropore size at sub‐angstrom level is proposed herein. Due to the varying activating strength and size of the alkali ions, the ultramicropore size can be finely tuned in the range of 0.60–0.76 nm as the activation ion varies from Li+ to Cs+. The carbons prepared by direct pyrolysis of alkali salts of carboxylic phenolic resins yield ultrahigh capacitances of up to 223 F g‐1 (205 F cm‐3) in ionic liquid electrolyte, and superior CO2 uptake of 5.20 mmol g‐1 at 1.0 bar and 25 °C. Such outstanding performance of the finely tuned carbons lies in its adjustable pore size perfectly adapted to the electrolyte ions and CO2 molecule. This work paves the way for a new route to finely tuning ultramicropore size at the sub‐angstrom level in carbon materials.

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Scenario analysis of ecosystem services (ES) can provide a scientific basis for ecosystem management. The objective of this study was to reveal the effects of future land use scenarios on ES in a mountain-oasis-desert system (MODS). We first simulated land use changes for the period of 2015–2035 in Altay Prefecture under three different scenarios: business as usual (BAU), economic development (ED), and ecological conservation (EC). We then evaluated water yield (WY), crop production (CP), soil conservation (SC), sand fixation (SF), carbon sequestration (CS), and aesthetic value (AV) and investigated the multiple interactions among ES at the regional and grid scales. The results showed that SC, CS, and AV continually increased, WY continually decreased under the three scenarios. Our study revealed that the multiple interactions among ES were spatially heterogeneous in the MODS and the spatial heterogeneities changed across scenarios. The locations of and causes for the formation of the multiple interactions among ES were identified based on spatial analysis. This information can help decision-makers develop targeted and differentiated ecosystem management strategies. This study can increase the understanding of the multiple interactions among ES. Our findings can provide a reference for studies of other regions with the MODS structure.

Background Quantitative evaluations of the relative impacts of climate change and anthropogenic activity on grasslands are significant for understanding grassland degradation mechanisms and controlling degraded grasslands. However, our knowledge about the effects of anthropogenic activities and climate change on the grassland in a mountain basin system in arid regions of Central Asia is still subject to great uncertainties. Methods In this research, we have chosen the net primary productivity (NPP) as an index for revealing grassland dynamics processes. Moreover, the human appropriation of net primary production (NPPH), which was calculated as the potential NPP (NPPP) minus the actual NPP (NPPA), was applied to distinguish the relative influences of climate change and human activities on the grassland NPP variations in a mountain basin system of Central Asia from 2001–2015. Results The results indicated that the grassland NPPA showed an increasing trend (35.88%) that was smaller than the decreasing trend (64.12%). The respective contributions of human activity, climate change and the two together to the increase in the NPPA were 6.19%, 81.30% and 12.51%, respectively. Human activity was largely responsible for the decrease in the grassland NPPA, with the area experiencing human-induced decreases accounting for 98.21% of the total decreased area, which mainly occurred during spring/autumn pasture and winter pasture. Furthermore, the average grazing pressure index (GPI) values of summer pastures, spring/autumn pasture and winter pastures were 1.04, 3.03 and 1.83, respectively, from 2001–2015. In addition, negative correlations between the NPP and GPI occupied most of the research area (92.41%). Discussion Our results indicate that: (i) anthropogenic activities were the primary cause of the reduction in the grassland NPP, especially grazing activities. (ii) For areas where the grassland NPP has increased, precipitation was the dominant climatic factor over temperature in controlling the grassland NPP changes in the study area. (iii) The findings of the current research indicate that some measures should be taken to reduce livestock pressure, and artificial grasslands can be built along the Irtysh River and the Ulungur River to relieve grazing pressure on spring/autumn pastures and winter pastures. Our results could provide reliable information for grassland management and the prevention of grassland degradation in arid regions of Central Asia.

Fluorinated graphene (FG) has been a star material as a new derivative of graphene. In this paper, a series of fluorinated graphene materials are prepared by using N, O-doped graphene aerogel as precursor via a direct fluorination method, and the effect of fluorination temperature on the FG structure is investigated. The prepared FG samples are systematically characterized by scanning and transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and Raman spectroscopy. It is found that the structure of FG, including features such as layer size, chemical composition, chemical bond state of the component elements, etc., is significantly related to the fluorination temperature. With the change of the fluorination temperature, fluorine atoms enter the graphene framework by a substitution process of the N, O-containing groups, including residual phenol, ether, carbonyl groups, or C–N groups, and the addition to CC bonds, subsequently forming a fluoride with different fluorine contents. The fluorine content increases as the fluorination temperature increases from 200 °C to 300 °C, but decreases at a fluorination temperature of 350 °C due to the decomposition of the fluorinated graphene. The prepared FG samples are used as cathode material for lithium primary batteries. The FG sample prepared at 300 °C gives a high specific capacity of 632 mAh g−1 and a discharge plateau of 2.35 V at a current density of 10 mA g−1, corresponding to a high energy density of 1485 Wh kg−1.