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Abstract Microparticle adhesion and resuspension are critical in studies of surface contamination, non-contact sampling, environmental and occupational health assessments, and surface cleaning. Direct adhesion measurement methods that evaluate the pull-out force are often limited to a range of operational conditions. The established analytical models need additional terms to account for roughness, morphology, and environmental conditions. The proposed aerodynamic method offers a non-contact evaluation of particle-surface adhesion force. In this work, aerodynamic detachment of silica microspheres in the 12–26 µm range from a smooth glass surface is studied experimentally. Computational fluid dynamics (CFD) calculates the drag and lift forces acting on the particles. The adhesion force is derived from the moment balance required to initiate the rolling motion of the particle. The aerodynamic forces acting on the particle, calculated by the CFD, agree with the theoretical values for a spherical particle in the shear flow in the Stokes regime (Re <1). The aerodynamic force calculations are extended to Re = 1–1000. The aerodynamic method shows a monotonically increasing dependency of the adhesion force with particle diameter; the results are consistent with the theoretical models and the published experimental data. The approach can be extended to more complex systems, including the effects of roughness, particle morphology and aging, and a range of environmental conditions. Highlights • The aerodynamic method for determining the particle adhesion force provides consistent results with the DMT and JKR models. • The drag force computed numerically is consistent with the modified Stokes flow theory for Re<1. For Re>1. • Relationship between the drag coefficient and particle is developed for 1 < Re < 10 3. • The lift force is consistently at least at an order of magnitude less than the drag force and several orders of magnitude less than the adhesion force. The lift can be neglected in the adhesion calculations of spherical particle. Graphical abstract fx1 [ABSTRACT FROM AUTHOR]

Land use transitions are an important research area in land system science. In seeking a feasible way to improve rural residents' livelihoods and rural development, this paper explores the mechanism and effects of farmland use transition on rural livelihood transformation from the perspective of the human-land relationship. The theoretical framework of rural livelihood transformation as affected by farmland use transition is established, and econometric models are used to test the effects based on empirical panel data from China for the period 2000–2017. The major conclusions are drawn as follows. In essence, farmland use transition is the redistribution of agricultural productivity on farmland, and rural livelihood transformation is a process of long-term and trend transformation of rural residents' livelihood capital, livelihood structure, and livelihood pattern. Land use transitions boost the transformation of rural livelihood by regulating the rural human-land interactive relationship and substitutional relationship of elements in agricultural development. For every 1% increase in farmland management scale transition and farmland efficiency transition, rural livelihood transformation can be improved by 3.748% and 3.854%, respectively. The direction and intensity of the impact of farmland use transition on rural livelihood transformation differ by area and topographic conditions. Furthermore, people's livelihood finances and farmers' planting decisions regulate the effects of farmland use transition on rural livelihood transformation. The authors argue that regulating land use transitions can be an important component of policy-making to promote rural livelihoods transformation, and rural development transformation. • Theoretical framework for rural livelihood transformation affected by farmland use transition is established. • For every 1% increase in farmland scale and efficiency transition, rural livelihood transformation can be improved by 3.748% and 3.854%, respectively. • Impact of farmland use transition on rural livelihood transformation is heterogeneous in different areas and terrains. • People's livelihood finances and farmers' planting decisions will regulate the effect of farmland use transition on rural livelihoods transformation. • Regulating land use transition can be an important component of policy-making to promote rural livelihood transformation. [ABSTRACT FROM AUTHOR]