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In this study, field monitoring testing and machine learning are used to analyze vegetated soil’s response to various rainfall events under natural environmental conditions. Parameters that reflect the soil, vegetation, and atmosphere of three monitoring points at different distances from a tree (0.5 m, 1.5 m, and 3.0 m) at a constant depth (0.2 m) are quantified and used for multivariate model development. A machine learning method, multi-gene genetic programming (MGGP), is used to formulate the relationships between two indices representing vegetated soil response and six selected influential parameters. Analysis indicates that for a complicated system, the MGGP method is suitable for establishing an efficient computational model under conditions of limited data. Global sensitivity analysis and parametric study are conducted, based on the obtained multivariate models, to reveal the effect of each influential parameter, indicating that rainfall pattern has much the same impact on variations in soil suction as rainfall amount and intensity and tree canopy do. An advanced rainfall pattern can trigger a more rapid response of vegetated soil than intermediate and delayed rainfall patterns can. Rainfall pattern’s effect on the descent rate of soil suction is nonlinear.

In this study, a machine learning method, i.e. genetic programming (GP), is employed to obtain a simplified statistical model to describe the variation of soil suction in drying cycles using five selected influential parameters. The data used for model development was recorded by an in-situ experiment. The image processing technology is used to quantify several tree canopy parameters. Based on four accuracy metrics, i.e. root mean square error (RMSE), mean absolute percentage error (MAPE), coefficient of determination (R2), and relative error, the performance of the proposed GP model was evaluated. The results indicate that the model can give a reasonable estimation for the spatiotemporal variations of soil suction around a tree with acceptable errors. Global sensitivity analysis for the statistical model obtained using limited data of a specific region demonstrates the drying time as the most influential variable and the initial soil suction as the second most influential variable for the soil suction variations. A case study was conducted using a set of assumed input variable values and validated that the simplified GP model can be used to estimate and predict the spatiotemporal variations of soil suction in rooted soil at a certain range.

A sequential ultrasound intensified photocatalytic reactors was investigated to degrade and mineralize typical endocrine disruptor, bisphenol A (BPA) using nanometer TiO2 as photocatalyst. The process parameters i.e., US power, TiO2 dosages, air flow rate and circulating liquid velocity of the reactors were optimized of the process. Under the optimum operation condition, nearly 90% and 80% BPA was degraded and mineralized in the reactor within 2.5 h. The combination of sonolysis and photocatalysis of TiO2 exhibits a synergetic effect, and benefits for BPA mineralization.

Air stripping of ammonia is a widely used process for the pretreatment of wastewater. Scaling and fouling on the packing surface in packed towers and a lower stripping efficiency are the two major problems in this process. New patented equipment that is suitable for the air stripping of wastewater with suspended solids has been developed. Air stripping of ammonia from water with Ca(OH)2, was performed in the newly designed gas-liquid contactor, a water-sparged aerocyclone (WSA). The pressure drop of gas phase was investigated in order to know the momentum transfer characteristic of the WSA. It was found that the gas phase pressure drop exhibited a different change tendency compared with the traditional aerocyclone, and could be divided into three characteristic stages, including low pressure drop, pressure drop jump and high pressure drop phases. The three different pressure drop areas corresponds to steady jet, spiral and fogged flow patterns of the liquid phase. The critical value for the air flow rate which caused the mass transfer coefficient to increase rapidly took place at the point where the steady jet was transformed into the spiral flow pattern.

Air stripping of ammonia is a widely used process for the pretreatment of wastewater. Scaling and fouling on the packing surface in packed towers and a lower stripping efficiency are the two major problems in this process. New patented equipment that is suitable for the air stripping of wastewater with suspended solids has been developed. Air stripping of ammonia from water with Ca(OH)2, was performed in the newly designed gas-liquid contactor, a water-sparged aerocyclone (WSA). The mechanism of the mass transfer process in the WSA was investigated using a CO2—NaOH rapid pseudo first order reaction system. The results indicated that there is a critical gas phase inlet velocity Ug. When Ug is lower than this value, the increase of the inlet velocity has a double function of both intensifying the liquid side film mass transfer coefficient kL and increasing the specific mass transfer area a; whereas when Ug is larger than this value, the major function of Ug increase is to make the water drops in the WSA broken, increasing the mass transfer area of gas-liquid phases.

Thiol-terminated oligonucleotide was immobilized to gold surface by self-assembly method. A novel amplification strategy was introduced for improving the sensitivity of DNA. hybridization using biotin labeled protein-streptavidin network complex. This complex can be formed in a cross-linking network of molecules so that the amplification of the response signal will be realized due to the big molecular size of the complex. It could be proved from the impedance technique that this amplification strategy caused dramatic improvement of the detection sensitivity. These results give significant advances in the generality and sensitivity as it is applied to biosensing.

To prepare lidocaine nanoemulsion and investigate its transdermal delivery ability in vitro.The optimal Km (surfactant/cosurfactant) value and the component proportion were determined by pseudoternary phase diagrams combined with Origin software analysis. The diameter and distribution range were detected by Zeta particle size analysis instrument, and the morphology of the nanoemulsion was observed by electron microscope. The permeation flux of lidocaine was determined in vitro using the modified Franz diffusion cell combined with HPLC, and the cumulative transdermal absorption amount and the apparent skin transdermal velocity were compared among nanoemulsion, gel and tincture containing 5% lidocaine. The permeation mode of lidocaine nanoemulsion was analyzed.The average drop size of lidocaine nanoemulsion was 29.8-/+14.4 nm, and 98% of the drop sizes ranged from 15.1 to 45.5 nm and 2% from 77.9 to 261.3 nm. The nanoemulsion drop showed a spherical morphology in a polydisperse system. The Kp value of the nanoemulsion (3.07-/+0.74 cm/h) was significantly higher than that of gel (1.27-/+0.35 cm/h) and tincture (0.97-/+0.18 cm/h), and the permeation rate of the nanoemulsion was 69.82-/+7.48 microg x cm(-2) x h(-1), which fitted the the Zero-order release dynamic procedure.The component proportion of lidocaine nanoemulsion can be conveniently obtained through pseudoternary phase diagrams and Origin software analysis, and the drop size, distribution, morphology and system type can be determined by Malvern Zetasizer combined with electron microscopy. The results also indicate that the nanoemulsion system with high permeation rate may provide a new promising means for local anesthesia.