Advanced Materials Research Vols. 183-185

Abstract: Twelve evaluation indices concerning the diversity, unification, uniqueness, people-orientedness, etc. were selected from the factors influencing the residential plant landscape in the study. Analytical hierarchy process was used to establish an objective and reasonable system of indices so as to establish a feasible evaluation system for the residential plant landscape to meet the actual needs.

Abstract: The urea inclusion was carried out to purify γ-linolenic acid (GLA). The single-factor, double-factor and orthogonal test were employed to optimize technical conditions. Single-factor tests showed that the best ratio of FFA: urea: alcohol was 1:3:8, the inclusion temperature was -15or-20°C and the duration time was 24 hours. Double-factor test indicated the optimal combination was A2B2 or A2B1. The best combination of the orthogonal test was A1B2C2D2 or A4B2C2D2. The ratio of filtrate and urea was 6:2 or 8:3, at the method of isolation was NO. II. Using urea inclusion, GLA purity was raised over 90% with a yield of 80%.

Abstract: Due to the existence of antibiotic residues, waste mycelium of lincomycin was difficult to be treated and used as resources, which had become a major problem in the production enterprise. So it is very necessary to isolate and screen lincomycin - degrading bacteria to biodegrade the waste mycelium. In this paper, Box-Behnken Experimental Scheme was performed to optimize the experimental conditions for the treatment of silica gel plates, and the visible spectrophotometry was used to determine the concentration of lincomycin in the silica gel plates to indicate the degradation capacity. The results showed that the optimal conditions were to add 4 ml of water to a silica gel plate, and immerse for 40min, and repeat this process for four times. Under these conditions, the linear correlation between the lincomycin concentration and absorbance was satisfactory in the calibration standards at the range of 0-5mg/ml (r=0.99976). The method precision values (RSD=0.1126%), accuracy values (RSD=0.2358%), reproducibility values (RSD=0.2358%), stability values (RSD=0.1129%) and recovery values (98.1318%) of lincomycin in silica gel aqueous solution were adequate. Application of this method to 1311 strain showed the lincomycin - degradation rate was of 35.81±2%. Taken together, we have established a simple, convenient, rapid and valid visible spectrophotometry method to detect lincomycin in silica gel plates for screening lincomycin - degrading bacteria.

Abstract: Based on the traditional time series methods, this paper researched a time series-exponential smoothing model that is built by SPSS statistical analysis software. In the application of the model, the original data of water consumption were in processed by a particular smoothing method first.Secondly, the processed data were used to build a time series-exponential smoothing model. On error test, we found that this forecasting model has advantages of better effect, high precision and minor error on urban water demand forecasing.

Abstract: The co-culture of fungus-bacteria was used for the bioremediation of petroleum hydrocarbon polluted mangrove sediment. The comparisons of single biosurfactant rhamonolipid and mixed biosurfactants (rhamonolipid and sophorolipid) added to enhance bioremediation were conducted in this study. The weight ratios of nC17/Pristane and nC18/Phytane were used as biomarker index in this study to monitor the progress of biodegradation progress of petroleum bioremediation test. The results revealed that the introduction of consortium of fungus-bacteria to petroleum hydrocarbons bioremediation was more efficient than the sum of the individual removal obtained in pure culture of fungus and bacteria. The introduction of rhamnolipid in bioremediation test of petroleum hydrocarbon in bioreactor E has higher removal of TPH than bioreactors of A, B, C, and D that without any biosurfactant added. And the result of bioreactor F demonstrated that the combination two different biosurfactant of rhamonolipid and sophorolipid provide a synergistic effects and lead to faster biodegradation than that added with single biosurfactant of rhamonolipid or sophorolipid in mangrove sediment. Conclusively, the combination of biostimulation and bioaugmentation approaches for petroleum bioremediation in mangrove sediment has achieved success in this study by co-culture of the fungus-bacteria amended with mixed biosurfactants, nutrients and aeration.

Abstract: Steam distillation oil (SDO) and simultaneous distillation oil (SDEO) were obtained from Tagetes Erecta L. leaf of Heilongjiang province by steam distillation method and simultaneous distillation method, respectively. The yields were 0.0943% and 1.005%. Compared the differentiation of essential oil through the GC-MS analysis, the result indicated that there were twenty-nine kinds of compounds can be confirmed from SDO and fifty-one kinds can be confirmed from SDEO. The two kinds of essential oil were assayed for affinity to scavenge sodium nitrite for the purpose of characterizing mechanisms of nitrite cleaning activity. Both show strong nitrite cleaning activity up to a concentration of 0.1mL.The maximum scavenging rate was 95.18% (SDO) and 54.28% (SDEO).

Abstract: In this paper, the two-dimensional renormalization group model for the failure process of a locked patch is designed according to the locked patch concept and renormalization group theory. The stress transfer among the blocks is defined with the conditional probability method. The critical probability P* of locked patch is obtained. By analysis the possible linkage between the failure mechanism of locked patch and evolution of landslides, it is found that the critical instability displacement of landslides has a dependency on the displacement at the onset point of accelerating creep, the number and the homogeneity of locked patches. At displacement less than the critical displacement, virtually no locked patch fails on a large scale. Above the critical displacement, the locked patch fails. After the failure of the last patch, the landslide would occur.

Abstract: This paper aims to study the technological conditions and adsorption mechanism of the rare-earth ammonia-nitrogen wastewater adsorption by unmodified water granulated slag and modified water granulated slag. The results showed that the optimum adsorption reaction time is around 60min for both of unmodified and modified slag; the optimum dosage of unmodified slag is 0.015g/mL, whereas it is 0.01g/mL for modified slag, correspondingly, the removal rate of ammonia-nitrogen could attain to (59.9±2.49) % and (79.24±1.21) % associated with unmodified slag and modified slag respectively. The ammonia-nitrogen removing process conducted by unmodified water granulated slag fits the Freundlich adsorption isothermal equation, conforming to physical adsorption. By contrast, the ammonia-nitrogen removing process accomplished by modified water granulated slag fits the Temkin adsorption isothermal equation and this process should be chemical adsorption.

Abstract: The effect of different tillage systems on the size distribution of aggregates and organic carbon distribution and storage in different size aggregates in a Hydragric Anthrosol were studied in a long-term experiment in Chongqing, China. The experiment included five tillage treatments, which are conventional tillage with rice only system (DP), conventional tillage with rotation of rice and rape system (SH), no-till and ridge culture with rotation of rice and rape system (LM), no-till and plain culture with rotation of rice and rape system (XM) and tillage and ridge culture with rotation of rice and rape system (LF), respectively. The results showed that the aggregates 0.25-0.05 mm in diameter accounted for the largest proportion in each soil layer under all treatments. The organic carbon mainly exist in aggregates in the 0.25-2 mm and 0.05-0.25 mm diameter in the plough layer, which mainly exist in the 0.25-2 mm in diameter in the bottom layer. Distribution of organic carbon in aggregates in the 0.05-0.25 mm diameter class was highest, followed by the aggregates in the 0.25-2mm diameter class. The organic carbon in aggregates under different tillage systems was in a decreasing order of LM (21.05 g·kg-1)> DP (14.13 g·kg-1)> XM (13.29 g·kg-1)> LF (12.54 g·kg-1) > SH (11.41 g·kg-1). The total organic carbon content showed a significant correlation with the amount of aggregates with diameter >0.005 mm. The results showed that the accumulation of soil organic carbon was mainly affected by aggregates in the >0.005mm diameter class.

Abstract: The impact of conservation tillage practices on carbon sequestration has been of great interest in recent years. This experiment analyzed the organic carbon status of soils sampled at depth increments from 0 to 60 cm after 20 years in a purple paddy soil. The tillage experiment was established in the Key Field Station for Monitoring of Eco-Environment of Purple Soil of the Ministry of Agriculture of China, located in the farm of Southwest University (30°26′N, 106°26′E), Chongqing. In this paper, five tillage treatments including conventional tillage with rice only system (DP), conventional tillage with rotation of rice and rape system (SL), no-till and ridge culture with rotation of rice and rape system (LM), no-till and plain culture with rotation of rice and rape system (XM) and tillage and ridge culture with rotation of rice and rape system (LF) were selected as research objectives to measure SOC storage and stratification ratio of SOC (CSR). The SOC storage under different tillage systems was calculated based on an equivalent soil mass. The CSR can be used as an indicator of soil quality because surface organic matter is essential to erosion control, water infiltration, and the conservation of nutrients. Results showed that in soil under no-till SOC was concentrated near the surface, while in tilled soil SOC decreased equably with the increase of soil depth. The difference of SOC contents between the five tillage systems was the largest in the top soil and the lowest in the bottom soil. The order of SOC storage was LM (158.52 Mg C•ha-1) >DP (106.74 Mg C•ha-1) >XM (100.11 Mg C•ha-1) >LF (93.11 Mg C•ha-1) >SL (88.59 Mg C•ha-1), LM treatment was significantly higher than the other treatments. The CSR of 0-10/50-60 cm was 2.65, 2.70 and 2.14 under LM, XM and LF treatments, while 1.54 and 1.92 under DP and SL treatments. We considered CSR>2 indicate an improvement in soil quality produced by changing from tillage to no-tillage, as well as changing from plane to ridge. Overall, long-term LM treatment is a valid strategy for increasing SOC storage and improving soil quality in a purple paddy soil in Southwest China.