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A high energy-efficiency capacitor switching scheme for successive approximation register (SAR) analogue-to-digital converters (ADCs) is presented. The switching method, verified on a 10-bit SAR scheme that uses bottom plate sampling, achieves an average switching energy and area reduction of 99.32 and 96.5%, respectively, with respect to the conventional solution. [ABSTRACT FROM AUTHOR]

Estimating cadmium (Cd) bioavailability and transfer to plants are important for food safety. We aimed to determine the dominant soil factors regulating the transfer of Cd from a wide variety of Chinese soils to Pak Choi (Brassica chinensis) and to establish a model for prediction of Cd uptake in B. chinensis. A greenhouse experiment was conducted in which B. chinensis plants were grown under 14-h 20±C light/10-h 16±C dark photoperiod for 60 d. The total Cd content in the plant and soil samples was measured. The Cd concentration in B. chinensis was positively correlated to the soil Cd concentration, and negatively correlated to the soil pH and soil organic carbon (SOC) content. The bio-concentration factors (BCF) measured in acidic soils (the maximum value being 0.551) were higher than those in alkaline soils (the maximum value being 0.366). Multivariable (pH, SOC, and total soil Cd) regression analysis could estimate the Cd bioavailability more accurately compared with the single-factor (total soil Cd) analysis. The most accurate Freundlich-type equation (Log[Cplant] = 2.34Log[Csoil] - 0.27pH - 0.23Log[SOC] + 0.92) was developed to estimate the Cd bioavailability using combined data from all treatments. The model described by us would be useful for estimating the bioavailability of Cd to B. chinensis in a variety of soils and would be helpful in assessing the risk of Cd contamination in soils. [ABSTRACT FROM AUTHOR]