Applied Mechanics and Materials Vols. 246-247

Abstract: Multi-object auctions usually involve the sale of many homogeneous or heterogeneous objects. Aiming at homogeneous goods auction (such as mine auction, energy material auction), this paper introduces the research history and the newest research trends, and presents many widespread theoretical and applications problems. Moreover, assumptions, main ideas, and conclusions of literature related to homogeneous goods auction are reviewed and commented.

Abstract: Taking the representative alluvial plain of the Yellow River-Fengqiu county as example, difference of available K (AK), total (TK) and total (TP) between topsoil and subsoil and corresponding factors was studied. The result shows that average content of AK in topsoil is lower than it in subsoil, spatial variation of AK in topsoil is similar with it in subsoil. TK in topsoil shows more randomness than in subsoil. TP in topsoil has a stronger spatial correlation than in subsoil. The spatial distribution of TK and TP are quite consistent with landform in topsoil and subsoil, but AK does not have this trend. The difference of TK between two layers is related with surface deposit and irrigation condition. AK is mainly affected by surface deposit and farming intensity such as fertilization. The difference of TP is unrelated with elevation, the distance to the Yellow River, roads and water channel and residential areas.

Abstract: Accumulation characteristics on 7 heavy metals of 3 indigenous pioneer plants (Ageratum conyzoides, Comnyza canadensis, Miscanthus floridulus) & their rhizosphere soil was investigated in wasteland of coalmine tailing in Mingshan. The chief results were as follows: (1) soil pollution was mainly due to the compound Cd-Mn-Cu, of which Cd average content of soil was 2.052 mg/kg (between 0.759 to 3.109mg/kg) and much higher than the national secondary standard of GB 15618-1995 (Environmental quality standard for soils in China), and of which Mn average content of soil was 421.215mg/kg (between 387.057 to 488.660 mg/kg) and serious pollution, and of which Cu content was 91.281mg/kg (between 39.522 to 270.308mg/kg) and had certain pollution but not so serious; (2) the absorption and accumulation ability to the Ni, Cd, Cu, Pb, Zn, Mn and Cr of soil heavy metal among 3 indigenous pioneer plants & their different parts of the plant such like the root, stem, and leaf was not the same, on the whole had the synergistic and antagonistic effect for 7 ele-ments in 3 plants, of whom Ageratum conyzoides had an obvious synergistic action for Ni, Cu, Pb, Zn and Mn absorption and was beneficial to suck up further elements from the soil in wasteland of coalmine tailing, and of Comnyza canadensis and Miscanthus floridulus had different synergistic and antagonistic effect for 7 elements, especially Comnyza canadensis and Miscanthus floridulus were the Cd hyperaccumulator plants. (3) Heavy metal content of Miscanthus floridulus in the body was the lowest, and its enrichment coefficient, translocation factor was obviously lower than that of the other 2 plants too, so absorption mechanisms to heavy metal of Miscanthus floridulus could been believed as excluders, relatively Mn, Pb, Zn, Cu and Ni content in the over-ground parts of Comnyza canadensis and Miscanthus floridulus & their enrichment coefficient, translocation factor was rather high, and their absorption mechanisms to heavy metal belonged to accumulators.

Abstract: Heavy metal pollution in Topsoil is increasingly serious. In the paper, we present a novel analysis method for heavy metal pollution in Topsoil using Back-propagation (BP) Algorithm and genetic algorithm (GA). Usually there were many methods, including differential equation, but accuracy of these algorithms is not high. To acquire position and analysis of heavy metal pollution, we introduce GA and BP neural network. First, we build BP model and acquire the optimal weights and thresholds of BP through optimization of GA. At last, we search for global optima position of heavy metal pollution sources by GA. Experimental results show that better performance can be obtained by combining GA-based BP and GA-Based optimization.

Abstract: The four north-central Shaanxi OCPs observed surface concentration of farmland were analyzed via GC-MS and GC/ECD, respectively, Xi’an observation area 6.110 ng•g-1, Tongchuan observation area 0.817 ng•g-1, Yan’an observation area 3.018 ng•g-1, an observation area in Yulin 5.286 ng•g-1, respectively. Be observed over the same period in Xi’an concentration of OCPs in air 325.773 pg•m-3, where the concentration of particles OCPs 160.883 pg•m-3, the concentration of gaseous OCPs 164.890 pg•m-3.Xi’an urban air particles and gas field surface soil OCPs and the OCPs was correspondence between the basic components of content, indicating that much of Xi’an OCPs in the air of dust released from the soil. The results show that the observation area at the same time with different content of each component of different OCPs, DDTs maximum concentration, mainly in the form of p, p’-DDT, BHC, followed by HCHs, mainly in the form of β-HCH; air, gas-eous and OCPs There are two forms of particulate, HCHs gas content was significantly greater than the particulate phase, DDTs substances content of particles greater than the gas content; OCPs in soil content and the physical nature of the soil, HCB, Chlordane, TN+CN and soil organic matter Content showed a significant positive correlation, chlordane, endosulfan, EnSO4 and soil acidity was a significant positive correlation, HCHs, DDTs and soil acidity were some negative.

Abstract: Through the study of the ecological and environmental characteristics, based on ecological and environmental explore ways of the urban wetland park planning and design of the new method, the breakthrough only pay attention to content the traditional concept of space planning, through the space structure planning realize wetland park ecological and environmental functions, from ecological, safety, view and admire, close water, culture, economic research and other aspects of the urban wetland park comprehensive effect, pay great attention to the material empty between the ecological and environmental problems behind, and to realize the biodiversity of the wetland park protection and water environment protection goal to provide effective way.

Abstract: In order to predicate the value of roadbed settlement in peat soil area, and adopt proper groundwork disposal method, based on ground distortion principle and subsidence and consolidated computation analysis, the paper carries on theoretical analysis and forecast to the rule of peat soil ground lamination subsidence and final settlement time-space variation. By the contrast theoretical analysis of peat ground to subside, the theoretical result and actual monitor data fit well, and it proves that adoptive theories and parameters are appropriate. These instruct practical significance to design and construction.

Abstract: In order to guide the resource prediction and exploration evaluation of low-permeability sandstone gas reservoir, the physical properties of this kind of gas reservoir are summarized from such aspects as lithology, porosity, permeability and the characteristics of capillary force, and the main controlling factors of the gas reservoir are analyzed. The analysis show that low-permeability sandstone gas reservoir is mainly characteristic of high capillary pressure, high bound water saturation, low and high porosity as well as low permeability. Rock composition and structural characteristics of the reservoir is the basis of the factors that can affect the compactness of the reservoir. The formation of the reservoir is mainly affected by deposition, diagenesis and late tectogenesis: deposition can affect the composition of minerals, the original physical properties of clastic sediments and others; diagenesis is the main stages of the densification of reservoir, where compaction, pressure solution, cementation and late dissolution are the causes of the densification of reservoir. Dissolution and rim chlorite cementation improve reservoir property; tectonization can have an effect of late transformation on the physical properties of clastic reservoir. At the same time, the fluid characteristics in the reservoir can also affect the permeability of reservoirs.

Abstract: The tolerance and remediation efficiency of six local wild plant species in petroleum-contaminated soils in the Yellow River Delta were conducted at three contaminated levels, i.e., uncontaminated soil (control), soil contamination by petroleum at 1.48% (w/w, TI), and soil contamination by petroleum at 2.96% (w/w, TII). After 60 days, six plant species showed different petroleum contamination tolerance and degradation capability in soil. The degradation ability of Setaria viridis, Alopecurus pratensis and Echinochloa crusgalli(L) Beauv was significantly higher than that of Festuca elata, Eleusine indica (P<0.05). Suaeda salsa had the least degradation ability. Plant had the high ability to degrade petroleum in the weak pollution soil, which might be due to the low re-straining effect on plant growth. Based on their petroleum contamination tolerance and removal ef-ficiency, we suggest Alopecurus pratensis, Setaria viridis, Echinochloa crusgalli (L.) Beauv and Festuca elata are suitable for petroleum-contaminated soil remediation in the Yellow River Delta.

Abstract: In terms of the spatial and temporal characteristics of the mineral resources, the demands of the work to coordinate with Ministry of Land and Resources concerning overall dynamic inspections and managements of mine reserves, based on market economy model, an dynamic estimated module of minerals resources and reserves, which is able to dynamically analysis and inspect the dynamic changes of mineral resources and reserves in space and time, is made in correspondence with the actual deman with computer technology and GIS technology. This module is developed through MapGIS re-develop tools with the utilization of visual programming language C#, in order to realize the functions of dynamic adjustment of industrial indicators such as cut-off grade adapting to the market price and cost, quickly calculation and dynamic analysis of mine reserves, the interactive and rapidly delineation of ore bodies and automatic mapping and output of prospecting line profile map, which will greatly improve work efficiency and the level of management of mining companies so as to increase the economic benefits.