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With ultra-wide bandgap and outstanding thermal properties, diamond-based high-power devices have excellent application prospects. The crystal structure and electronic property of the metal/hydrogen-terminated diamond (H-diamond) interfaces have been extensively studied experimentally, but the Schottky barrier height (SBH) theory at the metal/H-diamond interface has not been systematically investigated yet. In this work, SBHs of interfaces formed by H-diamond (111) surfaces with 12 metals (Y, Sc, Mg, Ag, Al, Ti, Cu, Co, Pd, Ni, Au and Pt) are investigated using ab-initio calculations. The fitted curve of the SBH with respect to the metal work function is obtained with a Fermi pinning factor of 0.30, which is close to the empirical value of 0.36. Due to the negative electron affinity of H-diamond, Schottky contacts can be formed with low work function metals, which is useful in device design to regulate the SBH and it is relatively easier to form ohmic contacts with high work function metals, leading to low contact resistances. Our work sheds light on the rational design of diamond-based semiconductor devices with low contact resistances. [ABSTRACT FROM AUTHOR]

Understanding the impacts of ecological projects on household livelihoods is important in ensuring their sustainability. However, existing studies typically cover only a limited, discrete temporal point. Insufficient study duration makes it difficult to determine the full impact and dynamics of a project, affecting the veracity of the results. Representing one of the world's largest investments in an ecosystem service programs, the Grain for Green Project (GGP) has an objective of increasing household incomes. Using data from 7112 questionnaires collected through 12 consecutive years (2007–2018) of field survey monitoring, this study examined the long-term impacts of the GGP on household livelihoods in the Beijing–Tianjin Sandstorm Source Control Project area through comparisons between participant households (PHs) and non-participant households (NPHs). The results show that GGP subsidies significantly increased household incomes only during the period 2007–2015, and their share of total household income decreased from 9.21% in 2007 to 1.62% in 2018. Subsidies for GGP cannot compensate farmers for losses due to the reduction in farmland. The above findings suggest that the effect of subsidies diminishes over time. Increased investment in jobs and skills training is needed to consolidate the GGP results. This provides new perspectives and empirical support for the study of international ecological compensation policies and sustainable development. [ABSTRACT FROM AUTHOR]

Understanding the interactions between land use and desertification in arid regions is crucial for both improving human well‐being and achieving the United Nations Sustainable Development Goals. However, there has been limited research on the effect of spatial scale on this relationship, especially within different land utilization function orientations. We used a revised coupling relationship index to analyze the complex interactions and dynamic changes between land use and desertification with multiscale and multifunctional oriented regions in the Tarim Basin, northwest China. Our results showed that the coupling relationship was more significant in small watersheds than in large watersheds. An inverted U‐shaped curve was observed for the coupling relationship with an increase in the proportion of cultivated land, which changed with the land utilization function orientations. The watersheds with a high proportion of unused land and a fragile ecological environment were dominated by negative coupling. Watersheds with roughly equal proportions of forest–grassland and cultivated land showed positive coupling and followed an inverted U‐shaped trend. Watersheds with a relatively high proportion of cultivated land may achieve a win–win situation with both the reclamation of cultivated land and the control of desertification. Our study proves the necessity of research about the coupling differences in different functional oriented regions and may also help to suggest action priorities to desertification control and ecological restoration. [ABSTRACT FROM AUTHOR]

In arid areas, land‐use change interacts with desertification through water resources. Since water is flowing, the interaction between land‐use change and desertification is not only local, but also regional. Previous studies have focused on the unidirectional influence of land‐use change on desertification, but little research has quantitatively examined the bidirectional coupling, especially contrasting the difference between intracoupling (interactions within a sub‐catchment) and telecoupling (interactions across different sub‐catchments) within a hydraulically linked watershed. To solve this issue, we introduced a vector autoregressive model and designed a strategy from intracoupling to telecoupling to examine the interactions between them in the Tarim River. In intracoupling, a negative relationship was found in most areas. The increase of the land‐use degree inhibits the desertification expansion, and this inhibition degree in the short term increases with the desertification degree. Conversely, the effect of desertification on land use is relatively smaller, and the feedback direction is related to land‐use degree. The region with a relatively low farmland exploitation intensity shows negative feedback and vice versa. In telecoupling, a positive relationship was found: Increasing land‐use degree in upstream sub‐catchment aggravates the desertification expansion in midstream and downstream sub‐catchments. Regarding the opposing unidirectional effect, after desertification expansion in midstream and downstream sub‐catchments, humans will slow down land exploitation in the upstream sub‐catchment, but this behaviour has a certain time lag. This study demonstrates that the special relationship found in telecoupling should be considered in the model development of desertification and land‐use simulation. [ABSTRACT FROM AUTHOR]