Applied Mechanics and Materials Vols. 675-677

Abstract: The oil pipeline burying divulging pollutant was taken as the object of study in this paper, the heat transfer and mass transfer process of which in the soil porous medium were carried by the numerical analysis. The oil phase change for multiphase flow leakage process for buried pipelines for oil, gas and water in the low temperature was considered, and the impact on multiphase leakage process of high and low viscosity of the oil phase viscosity properties was analyzed. It cited multiphase pipeline leak by using Fluent at different times during the course of the earth temperature field , the oil / water phase distribution , surface temperature, and the results showed that : there existed a big difference between the multiphase flow leakage process surface temperature changes and porous medium heat and mass transfer processes with the conditions of high viscosity and low viscosity conditions . Therefore, the impact of the physical properties on buried oil pipeline leak process at low temperatures is great.

Abstract: Due to the weak absorption of H₂O in the near infra red region, the frequency modulation (FM) is one of good technologies to increase the sensitivity of detection. This method is used to study the absorption spectra of water-vapor in the region around 814.65 nm. Compared to direct absorption method, the signal-to-noise of spectral signal is enhanced. Therefore, the laser FM is a good potential spectroscopic technology in the application of laser sensor for trace gas.

Abstract: This paper established mathematic and physic model of buried oil pipelines leaking in porous media of soil. Make use of FLUENT software to simulate crude oil phase change and non-phase change in the soil of cold regions. The result shows that: The temperature over the leakage hole of phase change diffusion process is higher than not considering phase change. The oil phase diffuse to the earth’s surface needs more time. And the speed diffusing to the underground is basically same. The earth surface temperature’s variation of leakage process without crude oil phase change lags behind the process considering phase change.

Abstract: In order to analysis the Heavy metals in the bottom mud at beng river, we put the river reach between the bridge of beng river beside the er’huang road and the bridge beside the yin’meng road as the main research object, survey 14 transects of bottom mud from three indications (Hg,Pb,Cr) of the river and build a relate standards about the pollution of bottom mud depend on the domestic standards, in this paper, we use the potential ecological risk index method which was putted forward by Swedish scientists Hakanson as the criterion of the pollution about heavy metals in the mud. The results show that: at the rive reach mentioned above, we found there are very high heavy metals content in the bottom mud.

Abstract: Adopting microwave digestion and ICP-AES method while detecting Ni, Cr, Pb, Cd, As and Hg in edible fungus of Liaoning province, results show that the acceptance rate of heavy metal in lentinus edodes, oyster mushrooms, pleurotus eryngium, agrocybe cylindracea, agaricus bisporus, black fungus, coprinus comatus, cordyceps militaris was above 90%, Hg was not checked out, only in exceptional sampals Pb, Cd, Cr have checked out but not exceed, Ni and As out of limits, but the superscale was very small, the lentinus edodes in Liaoning province in a great measrue was safty.

Abstract: A rapid extraction method involving ultrasound wave and microwave synergistic extraction (UMSE), followed by sample clean-up on a neutral Al₂O₃ cartridge, high performance liquid chromatography (HPLC) with fluorescence detection, was optimized for polycyclic aromatic hydrocarbons (PAHs) determination in Ginkgo biloba extracts (GBE). The optimum extraction conditions of UMSE were carried out with 5 g of GBE and 40 mL n-hexane/dichloromethane (1:1, v/v), on ultrasound wave and microwave simultaneous mode of working for 9 min for one time. The extraction mean recovery of total PAHs amounted to 88.69%. The optimized procedure, that presented good analytical performances could be applied to determine PAH content in GBE.

Abstract: Considered influence of buried pipeline leakage of crude oil pollutants multiphase flow migration phenomenon effects, numerical model was established to buried pipeline road multiphase leak process simplified for two-dimension problem, numerical simulation was used with the CFD software FLUENT on buried pipeline leakage of crude oil pollutants migration process caused pollution problem, calculation simulation was carried out in the two species workers condition of one phase flow and multiphase flow buried pipeline leakage of pollutants around earth temperature field, the speed field and the distributions of oil/water phase in the soil porous media. Analysis the comparison of results indicated that: 1) the affected region of temperatures spread above the buried oil pipeline was more slowly than either side of the rate of diffusion;2) During the buried pipeline leakage early, except the maximum of velocity near the leakage mouth, the other penetration regional velocity of leakage crude oil are very low.

Abstract: The distribution and source apportionment of 12 heavy metals including Hg, As, Cd, Pb, Cr, Ni, Cu, V, Co, Zn, Mn and Ba in atmospheric particulate matter (APM) at 5 samplings sites from Gansu, Ningxia and Inner Mongolia sections of the Yellow River of China in 2012 year were studied in this paper. The results indicated that Zn had a maximum mean concentration at T5 (Gansu Province), followed by As. The order of average concentrations of all heavy metals was as follows: Zn>Mn>As>Cu>Pb>Cr>V>Ni>Cd>Hg>Co, Ba. According to enrichment factors (EF), only Mn was seriously enriched at all sampling sites, especially at T4, which indicated that anthropic source is dominant and the others were not enriched. The results of cluster analysis (CA) showed that 12 heavy metals from 5 sampling sites were clustered into four different groups at the linkage distance of 10 and they came from a variety of sources such as fuel, fertilizers, agrochemicals and mining.

Abstract: Butterfly Lake provides an important function of ecological environment and campus service for Guangdong Ocean University. Based on the data which were collected in March,May, September and December in 2013, the water environment quality of Butterfly Lake was assessed. The results show that the key pollutant of Butterfly Lake is total phosphorus (TP). The average concentration of TP is worse than the national quality standards for Class V. The water quality appears an obvious difference in different monitoring time. In September the water quality is the best. The average of single parameter pollution index (Sj) is 0.75 and the water quality belongs to good environment area. The average of integrated parameter pollution index (WQI) is 1.76 and the water quality belongs to light pollution area. In December the water quality is the worst. Sj and WQI is 1.14 and 3.14. The water quality belongs to light pollution area and moderate pollution area, respectively. The comprehensive trophic state index is 70.38 in December. The eutrophication level is hyper eutropher. The other monitoring time belongs to middle eutropher. In order to improve the water quality of Butterfly Lake,the valid measure is to strengthen the management of wastewater discharge from the laboratory and the dormitory.

Abstract: In last ten years, significant sedimentation has occurred, particularly in the lower portions of riparian zone of the Three Gorges Reservoir. However, the sediment and related environment effect did no explore well. In this study, sediment and soil in situ were collected in riparian zone, Three Gorges Reservoir, and heavy metals were analyzed and assessment. Results demonstrated:(1) concentration of heavy metals (except Cr and Ni) in sediment were significantly higher than those in soil; (2) sediment was moderately polluted by Cu and Pb, while soil were unpolluted-moderately polluted by As and Cu; (3) all of heavy metals both from sediment and soil are a potentially minor risk. Enrichment of heavy metals in riparian sediment is probably of formation regime and anthropogenic activities related pollutant emission. Therefore, enhanced control of water and soil, and pollution in the upper stream of the Yangtze River and the Three Gorges Reservoir area are recommended.