Advanced Materials Research Vols. 1030-1032

Abstract: In this study, three bio-electrokinetic remediation experiments were carried out to study the external delivery of oil-degrading bacteria by electrokinetics and enzyme activities in saturated soil. Results showed that the oil-degrading bacteria could efficiently transport to the saturated oil-contaminated soil by electrophoresis and/or electroosmosis. Bacterial population increased from 6.02-7.75 log (CFU/g) in the control experiment to 8.53-12.83 log (CFU/g) after external bacterial delivery. Under unidirectional operation, the bacterial populations near the electrodes were lower than those in the middle of the soil as a result of unfavorable pH environments. In bidirectional experiment BEK-B, a relatively low bacterial population in the middle of the soil was observed after the experiment. The activities of catalase, polyphenol oxidase, and dehydrogenase have similar trends with bacterial population in the soil, indicating a good relation between the three enzymes and oil biodegradation of oil in soil.

Abstract: Sugar degree is an important indicator of red jujube internal quality. The main objectives of this paper are to minimize the collinearity between spectral variables, to find the variable groups which containing the lowest redundant information,and establish the model with better robustness by means of fewer variables. This paper uses SPXY (sample set partitioning based on joint x-y distances) to divide calibrating samples,and applies successive projections algorithm (SPA) to select the near-infrared spectral characteristic variable of southern Xinjiang jujube total sugar. To further establish the partial least squares (PLS) model with selected variables. The root mean square error of prediction (RMSEP) of the model is 2.8804. The correlation coefficient of prediction r is 0.9005.To compare the established PLS model results between SPA selecting variables and full spectrum. The results showed that: Firstly, the divided calibrating samples is reasonable in SPXY way.Secondly, SPA optimizes 9 variables of the full spectrum 1557 variables,and prediction effect of the established PLS model is better than the full spectrum PLS model.Finally,SPA can effectively select characteristic wavelength of component under test.

Abstract: This study describes an analytical method employing capillary gas chromatography (GC) using flame ionization detection (FID) that has been developed for the simultaneous determination of food preservatives in drinks, including sorbic acid (SA), benzonic acid (BA) and methyl paraben (MP). For this purpose, dispersive liquid-liquid microextraction (DLLME) was applied as a sample preparation technique. The DLLME conditions such as the types and volume of extraction solvent, the types and volume of the disperser solvent, pH value and salt addition were investigated and optimized. The method was linear in the ranges from 0.5 to 100.0 μg·mL^-1 for abovementioned preservatives with R² ≥ 0.9991. The DLLME procedure allowed efficient recovery of the analyted preservatives ranging between 91 % and 108 % with a relative standard deviation (RSD) ≤ 6.1 for the blank samples spiked with 20, 40 and 80 μg·mL^-1 of preservatives, respectively. The developed procedure was demonstrated to be a effective method for the analysis of preservatives in drinks. Furthermore, the method is simple, reproducible, envioronmentally friendly and inexpensive.

Abstract: The effects of four types of mulching models (surface tillage with straw mulching, no-tillage with straw mulching on furrow, no-tillage with stubble mulching, and no-tillage with straw mulching on ridge and furrow) on the root spatial distribution and the relationship between the roots and shoots of maize were investigated using stratified digging methods, with maize as the test crop. The distribution of maize roots was cone shaped and gradually extended from 20 cm to 40 cm below the surface during the elongation stage. Under the different mulch tillage models, the effects on maize root growth were positive. The mulching measures significantly affected the control and support of the early and later stages of maize growth. The maize significantly differed in the root weight density (P=0.026<0.05) and the root surface area (P =0.005<0.01) with different mulching measures. No-tillage with straw mulching on the ridge and furrow was the only mulching model in which the growth of the roots and leaves of maize was limited. However, the other maize growth measures were better than conventional tillage. In addition, no-tillage with straw mulching on the ridge and furrow had an advantage in terms of the growth of the surface roots, while stubble mulching and strip mulching had advantages in terms of the growth of deep roots and radial roots, respectively. Surface tillage with straw mulching was an ideal cultivation method for the cold and arid regions of North China and had significant advantages in terms of the growth of the root weight, root surface area and root-shoot ratio.

Abstract: For the experiment three different storage conditions were chosen: storage at room temperature of 22 °C in the light and in the dark and in the dark in a refrigerator at 4 °C. Parameters monitored were: peroxide value and changes in the content of α-, γ-and δ-tocotrienols and α - and γ-tocopherols during storage for 210 days (30 weeks). The peroxide value is an indicator of the content of primary oxidation products of oils. From analytical analyses results that the greatest destruction of grape oil occurs during storage at room temperature and access of light, where a peroxide value increased up to 484 meq. O₂/kg oil). The least intrusive method of storage was in terms of temperature refrigerator (4 °C) in the dark, when during 30 days of storage peroxide value had risen only to 71.9 meq. O₂/kg oil. Between these values ​​were values stored at room temperature in the dark (after 30 weeks storage 196 meq. O₂/kg oil). From these parameters is clearly showed that to the stability of oil contribute significantly both factors - temperature and light conditions. The same trend was also found in tocotrienols. At room temperature and access of light was complete decomposition of α-tocotrienol in the 9th week of storage, γ-tocotrienol at 30 weeks of storage and δ-tocotrienol in the 18th week of storage. The most stable seems γ-tocotrienol > δ-tocotrienol > α-tocotrienol. When stored in the refrigerator in the dark, there was practically no decomposition of α-, γ-and δ-tocotrienols whose contents remained completely unchanged.

Abstract: Mercury as a world wide pollutant gets much attention.The hazard of mercury differ from its forms.This paper review the transformation of mercury,especially in soil, and the remediation technologies of Mercury Contaminated Soil.

Abstract: The feasibility of using constructed wetland to treat saline shipyard wastewater was evaluated in this study. Constructed wetland, acting as an ecological engineering alternative, is capable of reducing NH₄⁺-N、TN、TP and COD from saline shipyard wastewater. The planted unit showed better capability of COD, TN and TP removal than unplanted unit obviously. Treatment performance of planted unit was found to be 77.7-89.1% for COD, 69.2~80.2% for TN and 54.5~85.9% for TP in the stable operation stage. However, the treatment performance of unplanted unit was found to be 55.3-72.4% for COD, 66.0~79.2% for TN and 55.4~85.3% for TP in the stable operation stage.

Abstract: Ultrasonic-degradation of the antimicrobial triclocarban (TCC) in aqueous solution with Fenton-like enhancement as a new treatment method was investigated. The effects of several important factors on TCC degradation were researched, including H₂O₂ concentration, solution pH. The results showed that US/Fenton-like system can effectively remove the TCC in aqueous solution. The removal rate of TCC can reach more than 94% at optimal conditions ( [H₂O₂]=2.0 mmol/L, pH=3.0).

Abstract: A novel alternating oxic-anoxic operation mode of shortcut nitrification-denitrification was developed in a sequencing batch reactor at ambient temperature. Operational parameters favorable for maintaining the shortcut nitrification-denitrification were investigated and optimized. The experiments showed that alternating oxic-anoxic shortcut nitrification-denitrification system was able to be an independent treatment process in domestic wastewater treatment. And the optimization approach was so efficient that the main pollutant discharge targets achieved Standard A of the first class in "Discharge standard of pollutants for municipal wastewater treatment plant". Moreover, the reliability of the operation strategy in this experimentation was proved, which indicated the excellent nitrogen removal performances.

Abstract: Biomass change and removal efficiencies of suspended solids (SS) along the process in the filter were investigated. As the normal operation of the biofilter process was often influenced by the blockage, the SS and the particle size of the backwash sludge along the process were also analysed, in order to find at which position the filter is easily blocked and what causes the blockage. The results showed that the bottom of upward flow biofilter had a higher removal efficiency of SS, with the removal rate of over 70%. The biomass and the height of the filter had an obvious regularity and the biomass increased as height of the filter increased, but the biomass at the lower middle of the filter decreased with the increasing height of the filter. At the same time, the SS and the particle size of the backwash sludge along the process in the filter also indicated the similar results.