Advanced Materials Research Vols. 955-959

Abstract: The purpose of this review is to aim a summary of the development in the use of different supports for the immobilisation of a heterogeneous Fenton catalyst, which areiron-containing materials. Various anchors and immobilisation methods that are universally employed to the remediation of wastewater are considered. Commonly, the immobilisation of a heterogeneous Fenton catalyst onto supportive material has chiefly been approved through one of two major routes; chemical route physical route or physical route. The advantages and disadvantages of various immobilisation methods to obtain a gigantic surface area iron-containing materials support is considered too.

Abstract: Gamma irradiation has been widely applied in biology and medicine in terms of biological effects from low doses stimulation to high-doses inhibition. This study investigates the physiological responses for plantlets of Pepper, Eggplant, and Chinese Cabbage by low-doses of ¹³⁷Cs-γ irradiation. The results show that the POD activity and the content of MDA and soluble protein increased after gamma irradiation except for Chinese Cabbage. A significant positive correlation was observed between POD and MDA. Soluble Protein and the others had a negative correlation for Chinese Cabbage. Mechanisms of plants under irradiation should have a more profound study in order to determine the correlation.

Abstract: Samples of corn straw, soils and environmental water were collected, and Benzo[a]pyrene (B[a]P) in samples was detected by means of GC/MS. Its levels in atmosphere, soils and environmental water are ranged from 17.6 to 18.4, 0.2 to 2.7 and 5.1 to 5.4μg/kg, respectively. To B[a]P in corn straw, the contribution of the atmosphere is dominant. B[a]P levels in soils where corn straw burned was higher than that where such burning not occurred, and higher levels of B[a]P in soils of suburban roadside and lower level in rural roadside were observed. B[a]P was detected in river water and rainwater, but it was not detected in groundwater. Although soil and environmental water contributed B[a]P to corn through root uptake, that will be very limited importance. For GC/MS, selected monitoring of molecular ions for target analyte and standard was performed instead of full scanning analysis.

Abstract: Magnetotactic bacteria (MTB) are microorganism found in lake sediments and have a chain like organelle called magnetosome which is composed of highly pure crystal of magnetite (Fe₃O₄). We cultured Magnetospirillum magnetotacticum (MS-1) with culture media containing heavy metal ions such as Fe (standard media), Fe/Zn or Fe/Co and study on a possibility of MTB as a tool for bioremediation. In culture media containing Fe, Fe/Zn or Fe/Co, the growth rate of the bacteria was almost same. We measured the magnetic properties of the dried cells. The saturation magnetization (M_s) and the saturation remanence (M_r) of MS-1 cultured in Fe/Zn or Fe/Co media were decreased, but the coercivity (H_c) and the coercivity remanence (H_r) were increased from those of MS-1 cultured in the Fe media. The value of M_r/M_s and H_r/H_c were ca. 0.5 and ca. 1.0, respectively. The changes in the magnetic properties of MS-1 cultured in Fe/Zn or Fe/Co media represent that MS-1 would take not only Fe, but also Zn or Co element in their environment. We discuss about a possible usage and advantages of MTB as a tool for bioremediation.

Abstract: Ecotoxicological responses of cadmium (Cd) on seed germination, electrolyte leakage and soluble protein of Trifolium repens cv. Rivendel seeds were studied. Seeds were exposed to different Cd treatments with concentration of 0-1250 μmol·L^-1 for seven days. In the present study, with the increasing Cd concentration, both of germination rate and germination vigor decreased. There was no significant reduce compared to the control under Cd concentration of 10 μmol·L^-1. With the pollution levels strengthen to 1250 μmol·L^-1, germination rate and germination vigor were significantly restrained. With the increasing Cd concentration, electrolyte leakage increased gradually. Electrolyte leakage reached nearly one times of the control under Cd concentration of 1250 μmol·L^-1. Soluble protein content increased under Cd concentration of 10-50 μmol·L^-1 and then decreased with Cd concentration increased continuously.

Abstract: The performance of Xian-He scale inhibitor was evaluated by experiment study with the method of scaling ion balance. The results imply that both of the scale inhibitor show good antiscale performance. The amount of calcium and magnesium ions decreased obviously and the scaling reduces. When the scale inhibitor NO.1 was added into the sample by 9ml/L, calcium and magnesium ions content was high and basically remained unchanged. The best dosage of the scale inhibitor NO.2 is 12mL/L. As the temperature rise, the amount of calcium and magnesium ions is declining. With the same dosage, the amount of calcium and magnesium ions in the sample of the scale inhibitor NO.1 is higher than that in the sample of the scale inhibitor NO.2. Therefore, the performance of the scale inhibitor NO.1 is better than the scale inhibitor NO.2.

Abstract: The porous ceramic support was realized at various temperature range from 1200°C~1300°C using α-Al₂O₃ as main material, carbon powder as pore-former, kaolin clay and titanium dioxide as sintering aids and polyvinyl alcohol (PVA) as adhesives. The microstructures of sintered body were significantly affected by the amount of pore-former and sintering temperature. The results indicated that the porosity dramatically increased and the pore radius increased from 2.9 μm to 3.2 μm as carbon powder addition increased from 3 wt.% to 12 wt.%. Correspondingly, their pure water flux depending on the pore structure parameters of the support increased from 1.37 to 4.53 m³.m^-2.h^-1.bar^-1. To prepare porous alumina support with 40% open porosity, carbon powder up to 10 wt.% is appropriate. Sintering experiments showed that the optimum sintering conditions are the sintering temperature of 1300 °C and 2 h holding time at this temperature.

Abstract: The multi-effect distillation (MED) process is one of the oldest process in desalination of seawater. This technology has been used for water and heat recovery from the petroleum waste in Liaohe Oilfield. However, the scale formation is one of the main problems that encountered in the operation of different plants. The temperature of the first stage of the MED evaporation is higher than 138 °C. Therefore, both the scale inhibition and removal technologies should be adopted. The Belgard EV 2050 scale inhibitor produced by Ciba-Geigy is recommended to be used to inhibit the scale due to the excellent scale inhibiting performance. Scale removal technology also needs to be adopted regularly for device descaling in addition to the scale controlling technology. The sulfamic acid (concentration of 5% -10%) can be selected as the acid cleaning agent with a certain amount of inhibitor added.

Abstract: In this paper, poly aluminium chloride (PAC) was used to remove phenol and aniline from the aqueous phase .The adsorption properties of this process was investigated by zeta potential measurement, infrared spectroscopy and the analysis of pollutants structure and adsorption kinetic. The results described that not only electrostatic attraction but hydrogen adsorption were the main mechanism of both the phenol adsorption and the aniline adsorption. The pseudo second-order kinetic equation could best describe these two adsorption kinetics. The calculated activated energy of adsorption processes of phenol and aniline were 47.2KJ/mol and 44KJ/mol, respectively, which indicated that the adsorption process was chemisorption. Friedrich model was fitter to describe the adsorption isotherm of these two adsorption processes.

Abstract: In order to investigate the potential of sequencing batch biofilm reactor (SBBR) technology of two-sludge system for denitrifying dephosphatation (A₂ON process),we build a tab-scale experiment .Then find that the simultaneous removal of phosphorus and nitrogen in the two sludge system is possible .By the control of COD/TN ratio ,highly effective simultaneous nitrification and denitrification is achieved in the A2ON system.And the ratio of denitrification is 85%, the ratio of dephosphatation is 87%.It also demonstrates that the process is stable ,at the same time decrease the effect of dephosphorization and denitrification by the limited carbon source.