Advanced Materials Research Vols. 726-731

Abstract: The amount of soil total soluble N (TSN), NH₄⁺-N, NO₃^--N and soluble organic N (SON) declined significantly with increasing of sampling depth (P < 0.0001). Compared with CK, application of chicken manure significantly increased the amount of soil TSN and NO₃^--N by 77.0% and 213.0% in the CM20 treatment, and 176.4% and 766.4% in the CM 30 treatment, respectively (P < 0.0001). The amount of soil NH₄⁺-N was lower in CM20 treatment than CK and CM30 treatments. However, the amount of soil SON was higher in CM20 treatment than CK and CM30 treatments (P < 0.0001). Proportion of NH₄⁺-N to TSN was lowest. Application of chicken manure remarkably increased the proportion of NO₃^--N to TSN, and decreased that of NH₄⁺-N and SON to TSN (P < 0.0001). Soil SON accounted for the majority of soluble N irrespective of soil layer in CK and CM20 treatments, and followed by NO₃^--N. However, the trend was reversed in CM30 treatments. This result indicated that application of chicken manure significantly increased the amount of soil soluble N, especially SON and NO₃^--N, which may extend N leaching risk into deeper soil layer.

Abstract: Laolongdong Underground River used to be important drinking water source, but the water quality has been deteriorated since 1990s and the underground river becomes a sewer nowadays because of anthropogenic and urbanization influence. In order to find out the impacts of water-bedrock interaction, domestic sewage and agricultural activities on groundwater, the chemical characteristics of the groundwater were monitored each month to research the contamination sources and the contributed factors. The result shows that the groundwater is characterized as the HCO₃-SO₄-Ca type, which implys that groundwater geochemistry is controlled by middle and lower Triassic carbonate rocks. Moreover, the concentrations of K⁺, Na⁺, Cl^-, and PO₄^3- reveale an increasing trend and NO₃^- deceasing from 2008 to 2012. According to general contamination sources, the data implys that urbanization process and land use changing caused karst ground water pollution process and contaminations convert from agriculture effort to sewage and animal feces effort.

Abstract: Four diesel fuel degrading microorganisms were isolated from soil and sea water from Crude Oil Terminal at Tianjin Port using diesel fuel as sole carbon source, and they all could degrade diesel fuel. The initial diesel fuel concentration in the culture medium was optimized and was 1.5 g/L. The ability of the four strains to degrade diesel was compared by spectrophotometer with the initial diesel concentration at 1.5 g/L. The results showed that the strain C1 had the highest degrading activity, which could degrade 32.59% of diesel in 7 days. The strain C1 was further identified by 16S rDNA sequence analysis as Rhodococcus erythropolis, and the phylogenetic tree of the strain C1 was constructed.

Abstract: Through the soil column experiments, the migration behavior of heavy metal copper ions in saturated sandy loam is analyzed, and it is found that the inflow solution with high concentration is conducive to the migration of copper ions. In the meantime, the software package of CXTFIT is utilized to conduct fitting for the outflow dynamics of copper ions with deterministic equilibrium model and non-equilibrium two-zone model, and predict the changing process of copper ion concentration at the different depths of soil column over the time. The results show that in the indoor saturated homogeneous conditions, the simulation accuracy of fitting parameters that applied deterministic equilibrium model is higher than that used the non-equilibrium two-zone model. Moreover, the influence of fixed water on the copper ion migration can be ignored.

Abstract: The subcellular distributions of cadmium, chromium, copper, plumbum and zinc in hyperaccumulator (Pterts vittata and Solanum nigrum) and accumulator (Conyza Canadensis and Digitaria sanguinalis) had been studied in pot experiment. The results showed that hyperaccumulator and accumulator had different accumulation capacity of five heavy metals. The total content of five heavy metals in four plants roots was followed the order: P. vittata > S. nigrum > D. sanguinalis > C. Canadensis, and the total content of five heavy metals in four plants shoots was: S. nigrum > D. sanguinalis > P. vittata > C. canadensis. So, S. nigrum is the best repair material, followed by D. sanguinalis. The subcellular distributions of five heavy metals in the same hyperaccumulator or accumulator were different, indicating that different plants had different detoxification mechanism for different heavy metals. The proportion order of subcellular distribution of total heavy metal content in four plants roots was: F1 > F3 > F2, and the shoots had the same order. It could be conclude that plants weaken the toxicity of heavy metal by accumulating more heavy metal in the cell wall.

Abstract: Yeast SP1 was selected from the three strains to remove chemical oxygen demand (COD) in wastewater from refining part of N, 2, 3-trimethyl-2-isopropyl butanamide (WS-23). The effects of some factors on the degradation for wastewater from refining part of WS-23 were investigated and the optimum conditions for biological water treatment by yeast SP1 were obtained through orthogonal experiments. The results indicate that this wastewater can be treated directly by yeast without any pre-treatment and the best conditions are as follows: inoculum is 10% (v/v), reaction temperature at 30 °C for 48 h. Under these conditions, the total COD removal efficiency can reach 87.11%. In addition, according to Monod model, the kinetics parameters were obtained from the experiments by determining influent COD (S₀), effluent COD (S_e), biomass (X) and the kinetics of COD removal was established, furthermore, the difference of experimental and calculated values was within 1 hour by testing.

Abstract: Six benzimidazole derivatives were synthesized and charactrized by IR spectra, 1H-NMR spectra and MS spectra. The coordination reaction of the derivatives with CuCl₂. And six novel Cu (II) complexes with the derivatives were prepared and characterized by UV spectra, IR spectra and elemental analysis. The catalytic degradation of methyl orange aqueous solution was investigated using the complexes as catalysis in presence H₂O₂ by HPLC method and Vis-spectrophotometry. The result of characterization showed that there are four coordination sites around Cu (II) in all complexes, which are respectively occupied by one sulfur atom (from the derivative), one nitrogen atom (from the derivative), one oxygen atom ( from the OH^-) and one chlor atom (from the Cl^-). The degradation of methyl orange indicated that all the complexes show the properties of enzyme activity. And the main degradation products determined were hydroquinone and maleic acid.

Abstract: Coal fly ashes are a coal combustion product at high temperature. With a certain porous structure and large specific surface area, they have certain adsorption capacities and can be used as the materials for watewater treatment.But limited by the adsorption properties, the raw coal fly ashes have a very low pollutant removal efficiency, and can not meet the practical requirements of wastewater treatment. Therefore, researches now focus on the coal coal fly ashes modification, including increasing the active components in them, enlarging the specific surface area to improve their performance, and to enhance their wastewater treatment effects.Aiming at providing some references of their integrated utilization in wastewater treatment, the modification methods and application status of the coal coal fly ashes are summarized.

Abstract: The intrusion of pathogens into ballast water, not only destroys marine ecological environment, but also threatens human health. The study synthesized a new cobalt complex with a ligand of 3-pyridine-4-benzoic acid by hydrothermal synthesis method. Its structure was characterized by elemental analyzer and single crystal diffractometer, and its infrared spectroscopy, thermal stability and inhibitory activity were analyzed. The results show that the complex belongs to the monoclinic system and space group C2 / c, with unit cell parameters a = 8.2484 (9) Å, b = 10.3371 (11) Å, c = 12.2031 (14) Å, α = 89.588 (2) °, β = 87.0870 (10) °, cell volume = 982.03 (19) Å3, Z = 2, F (000) = 508, D_calc = 1.709mg/cm³, R1 = 0.0391 and wR2 = 0.0807. The asymmetric unit of the complex consists of the two Co ions, four ligand molecules and two coordinated water molecules, each center Co ions forms a hexacoordinated distorted octahedral structure. The MIC of complex for Escherichia coli, Salmonella and Vibrio parahaemolyticus in ballast water are respectively 78μg/mL, 39μg/mL and 78μg/mL, and its antimicrobial effects is better than ligands, which can be used as a novel bacteriostatic agent of ballast water.

Abstract: Response surface methodology (RSM) with central composite design was adopted to investigate the optimum condition for carbohydrate released from hydrothermal pretreated sludge in an autoclave used for WAO (wet air oxidation). Temperature, time and stirring rate were chosen as variables. The maximum carbohydrate release (1356.8 mg/L) was estimated at the temperature of 161.2 °C, the time of 48 min and the stirring rate of 661 r/min. This statistical method could precisely optimize reaction conditions and predict the experimental data. Only 11.2 mL methane was generated with little hydrogen production of raw sludge. In contrast, hydrogen production potential of 25 mL was reached by using supernatant as substrate with a COD removal of 78.14%. Hydrogen yield was increased from 0.13 mL/g-VS (raw sludge) to 13.16 mL/g-VS (supernatant of pretreated sludge).