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Atmospheric water is one of the main water resources for plants in arid ecosystems. However, whether deep-rooted, tomentum-less desert trees can absorb atmospheric water via aerial organs and transport the water into their bodies remains poorly understood. In the present study, a woody, deep-rooted, tomentum-less plant, Haloxylon ammodendron (C.A. Mey.) Bunge, was selected as the experimental object to investigate the preconditions for and consequences of foliar water uptake. Plant water status, gas exchange, and 18 O isotopic signatures of the plant were investigated following a typical rainfall pulse and a high-humidity exposure experiment. The results showed that a high content of atmospheric water was the prerequisite for foliar water uptake by H. ammodendron in the arid desert region. After atmospheric water was absorbed via the assimilating branches, which perform the function of leaves due to leaf degeneration, the plant transported the water to the secondary branches and trunk stems, but not to the taproot xylem or the soil, based on the 18 O isotopic signatures of the specimen. Foliar water uptake altered the plant water status and gas exchange-related traits, i.e., water potential, stomatal conductance, transpiration rate, and instantaneous water use efficiency. Our results suggest that atmospheric water might be a subsidiary water resource for sustaining the survival and growth of deep-rooted plants in arid desert regions. These findings contribute to the knowledge of plant water physiology and restoration of desert plants in the arid regions of the planet.

Lubricant viscosity is one of the key parameters in hydrostatic bearing research. In order to solve the load capacity of hydrostatic bearing in the heavy equipment, viscosity-temperature equation of lubricant film is established, and the viscosity-temperature curve is fitted by B-Spline curve. Finite volume method is used on numerical simulation of pressure field of heavy hydrostatic bearing in constant and variable viscosity respectively and in different rotational velocity, whereafter, viscosity influence on load capacity of heavy hydrostatic bearing is discussed. The results show that, viscosity impose a minor influence on cavity pressure of hydrostatic bearing when rational velocity is low; whereas, when rational velocity is high, especially to the heavy hydrostatic bearing which with high liner velocity influence of viscosity changing must be taken into account in calculation. Numerical simulation results reflect the pressure distributing state of bearing veritably; furthermore, these provide theoretical basis for hydrostatic bearing design and lectotype in practical application.