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ObjectiveTo reduce the content of cadmium in rice， the method of cadmium removal from rice was established and the extraction conditions were optimized by response surface methodology.MethodsThe cadmium extraction rate was used as the index to screen the cadmium removal methods. Commercially available cadmium positive rice was chosen as the test sample and four kinds of food grade organic weak acids were chosen as extractants. The concentration of acid solution， extraction time， solid-liquid ratio and rice powder particle size were used as independent variables to carry out the single factor extraction. And the optimal conditions for removing cadmium from rice was obtained by response surface design.ResultsThe optimal conditions for removing cadmium from rice were 4.2% acetic acid solution， 11 min extraction， liquid-to-material ratio 13：1 （mL/g）， and at least 50 mesh for rice flour. Under these conditions， the average removal rate of cadmium in rice was 98.67%.ConclusionThe experimental model is reasonable and the optimized extraction method is feasible. The removal or reduction of cadmium in raw rice is realized with optimal cadmium extraction conditions， which provides a scientific method for the research on cadmium removal from cadmium-contaminated rice.

In this study, The 30 mol% La-Y co-doped HfO2 was prepared by solid-phase synthesis and the effect of the doping content of La element on the phase structure and high temperature phase stability was investigated by XRD. The results show that LaYSH is pyrochlore p-phase + fluorite c-phase when the doping content of La element is 6 and 9 mol%, and a single fluorite c-phase when the doping content is 0-3 mol%. After sintering at 1600 °C for 50 h, 0, 1 and 2 LaYSH remained as a single fluorite c-phase, 3 LaYSH produced 2.54 wt% pyrochlore p-phase, and the pyrochlore p-phase content in 6 and 9 LaYSH decreased to varying degrees. The prepared 0, 1 and 2 LaYSH coatings all had a single c-phase and remained unchanged in the single c-phase when sintered at 1600°C for 50 hours, demonstrating their good high temperature phase stability.

Ice accumulation on high voltage insulators can cause accidents by flashover across the ice-covered insulators. The ice accumulation can be reduced by changing the insulator surface properties by application of a semiconducting RTV silicone coating. This method is based on the hydrophobicity and semiconductivity properties of the coating. The mechanism for reducing ice accretion is analyzed theoretically. Experimental results are presented to validate the effectiveness of the semiconducting RTV coating at reducing ice on insulator strings. The results show that the coating on the insulators delays ice formation and reduces the amount of ice. Index Terms--Ice, insulator, semiconducting, coating, RTV, flashover, hydrophobicity.

Based on artificial icing test results, it was found that the dc flashover voltage of iced insulator strings was non-linear with different string lengths. An experimental formula of flashover voltage on iced insulators of different string lengths is introduced in this paper. Icing tests were carried out on different kinds of insulators including DC antifog, double-shed and three-shed insulators. Under serious ice conditions, the DC flashover voltages of the different types of insulator strings were very close. The flashover voltage of energized iced strings was a little higher than that of de-energized ones. Index Terms--Iced insulator string, dc flashover, flashover, overhead line.

Organosilicone adjuvants are widely used to increase insecticide application on targeted surfaces. In this work, our aim was to investigate side effects of imidacloprid treatment, either applied alone or in combination with organosilicone compounds, against Chrysoperla nipponensis, an important predator of aphids. Four types of organosilicones were mixed with imidacloprid at different concentrations. The toxicity of the mixture to C. nipponensis was measured under laboratory conditions. The LC50 and LC30 of imidacloprid applied alone and in combination with 0.05% organosilicone were determined. Imidacloprid (LC30) applied alone or in combination with 0.05% organosilicone was used to treat second instar larvae of C. nipponensis; thereafter, its effects on the growth, development, longevity, reproduction, and predatory ability of C. nipponensis were evaluated The results demonstrated that the organosilicone Silwet L-77 reduced the LC50 and LC30 of imidacloprid to 6.09 (95% CI: 2.31–9.42) and 10.95 mg/L (95% CI: 8.16–13.63), respectively, and enhanced imidacloprid toxicity to C. nipponensis, as reflected by the resulting extension of the growth and developmental period, reduction in female longevity, and inhibition of reproduction. When applied alone or in combination with an organosilicone, imidacloprid reduced the consumption of Corcyra cephalonica eggs by C. nipponensis. The functional response of C. nipponensis treated with imidacloprid alone or in combination with organosilicone was type II. Concomitantly, the attack rate was reduced and the handling time of prey increased. [ABSTRACT FROM AUTHOR]