Advanced Materials Research Vols. 347-353

Abstract: Steel slag, fly ash and lime were chosen as pretreatment and grinding materials of fluorgypsum, then the grinding effect and cementitious property of fluorgypsum were studied. PH of pretreatment fluorgypsum increased to 8 when 1.5% lime, 5% steel slag and 12.9% fly ash were added .Specific surface area, fractal dimension and medium diameter of the modified fluorgypsum reveal that the best grinding aid is steel slag. SEM analysis show that there were still large particles when 1.5% lime or 12.9% fly ash were added in fluorgypsum and grinding, the fluorgypsum particles sizing were small with distribution uniformity after grinding when it was pretreated by 5% steel slag. Mortar strength results show that the fluorgypsum with 5% steel slag had good strength after pretreating and grinding.

Abstract: Wind energy has been most prevalently utilized to generate electric power due to non pollution to the environment and the conservation of fossil fuel resources. The energy generated from wind turbine depends on the wind site characteristics and the wind turbine parameters. So, the choice of certain wind turbine for specific site is very important in terms of price of electric energy generated from wind energy system. Therefore, optimal choice of wind turbine is one of the most crucial issues in the design of wind energy system, which can utilize wind energy as efficiently as possible and achieve the best economic benefits. So this paper introduces a new and simple mathematic formulation for the wind turbine-site matching problem, based on wind speed characteristics of any site and the power curve parameters of any wind turbine. Wind speed at any site is characterized by the scale parameter (c) and the shape parameter (k) of the Weibull distribution function. The power curve parameters of any wind turbine are characterized by the cut-in, rated, and furling speeds and the rated power. The new formulation method is derived based on a generic formulation for the product of the Capacity Factor (CF) and Normalized Power (P_N). Three case studies are also presented to demonstrate the effectiveness of the proposed method to choose between a group of wind sites and a list of commercial wind turbines.

Abstract: The objective of this study was to determine the baseline concentrations of trace elements in grassland topsoils from 155 soil sampling sites in West Jilin province, Northeast China, to establish the relationships between the trace metal contents and soil physicochemical properties and major oxide contents and among trace metal concentrations themselves, and to identify the possible sources of trace element in soils. The baseline concentrations of trace elements(mg/kg) were: As 3.12-14.18, B 16.17-49.08, Cd 0.037-0.127, Co 0.96-15.28, Cr 18.87-60.83, Cu 10.81-24.75, Hg 0.004-0.035, Mn 171.25-657.87, Mo 0.08-1.15, Ni 6.79-30, Pb 12.58 -26.08, Se 0.03-0.36, and Zn 18.93-61.03. The upper baseline limits of these elements were all less than the Chinese Environmental Quality Standard for Soils, the Dutch Intervention Values for Soils, implying that trace element contents in the studied soils were of the safety levels.Fe2O3 and Al2O3 had stronger correlations with most trace elements than other oxides, and Co,Cr,Cu,Mn, Ni were highly correlated one another. Three types of geochemical associations were distinguished from this study:the first association involving As,Co,Cr,Cu,Mn,Mo,Ni,Pb,Zn,Al₂O₃ and Fe₂O₃ was mainly associated with Al,Fe-Mn oxides and/or with the Al-bearing clay minerals, suggesting that the trace elements were mainly derived from lithogenic and pedogenic processes; the second association including Se, Hg, Cd, CaO and organic carbon was mainly associated with organic matter and calcium oxides, showing that Se,Hg and Cd were mainly contributed by anthropogenic sources; the third association containing B, Na₂O, K₂O, MgO, pH, and electrical conductivity was mainly associated salinization processes of soils, implying that alkaline pH and high Na contents would enhance B concentration of soils.

Abstract: The paper conducts a quantitative study on the accumulative effect of the sedimentation and release of the sediment pollutants in the offshore area from Guanhe to Liezihe Estuary of Jiangsu along China coast. The study begins with the index of major pollutants in the sediment of this area and establishes the calculation relations of them between the water over the seabed and sediment pollutants. The sedimentation flux of suspended substances is calculated taking into account the mud-sand absorption in the river estuaries and the change of sediment release with time and space. Hydrodynamic force as the basic principle as well as the determining factor for offshore sediment release is analyzed in the last section of the paper. The model for the sedimentation release and the calculation formula for the sediment release ratio are established, and related parameters are set based on actual measurement and analysis of space attenuation of sediment release. Innovation is made for the “method of concentration difference location for sediment mixture” and the increment of pollutants and decrement of environmental capacity within a specific area are calculated. Calculation and verification are also carried out based on the data from actual measurement.

Abstract: In order to explore the surface layer wind energy characteristics in Jiangsu coastal area, MM5 model and CALMET model and wind observations data are used in this paper. The comparison of simulated wind speed and observed wind speed shows that the MM5 and CALMET model can well simulate wind resource distribution and the simulated result is well agreed with observation. The results show that (1) Wind Resource in coastal area is more abundant than other area in Jiangsu Province;(2) Wind speed and wind power density in winter and spring are higher than that in summer and autumn;(3) predominant wind direction is NNW-N and SE-SSE.

Abstract: The incorporation of cadmium into clinker during the co-processing of waste with cement kiln was investigated. Cadmium contained reagent was added to the cement raw meal to produce clinkers after clinkerization process. XRD analysis and SEM-EDS analysis were employed to indentify the major mineral phase of clinker and the cadmium contained mineral phase. Leaching test, sequential extraction procedures were employed to evaluate the leaching potential of cadmium in clinker. The results show the stabilization rate of cadmium during the clinkerization process is low. The incorporation ratio of cadmium in C2S is 0.32%~1.14%, the incorporation ability of cadmium in C2S is higher than C3S. The major mineral phases of clinker with the incorporation of cadmium were CH, C3S and C2S. The average leaching concentration of cadmium of clinker was 1.4 μg/L, which was higher than the blank samples. BCR Sequential extraction procedures analysis of the clinkers show exchangeable, water and acid-soluble fraction and residual fraction were very small, while the reducible phase of cadmium was up to 95.13%.

Abstract: In order to assess the performance of the two-dimensional (2D) large eddy simulation (LES) as a computational tool for analyzing separated flows. LES in various models has been developed to simulate turbulent flows, especially to separated flows. In this investigation, 2D LES is used to simulate flow past a wind turbine airfoil in deep stall which is a classical separated flow proved by experiments. The results of 2D LES are compared with that of a 3D model using RNS/LES hybrid methods and with experimental data. This shows that the 2D LES method can not only be used to simulate separated flows, but also the calculation time of 2D LES is significantly decreased to compare with the 3D model using RNS/LES hybrid methods.

Abstract: In order to achieve the digital management of null-pollution agricultural products certification and by adopting techniques such as Web Service, distributed database and workflow, this essay has completed the design and development of the system based on the J2EE platform. It includes certification data service subsystem, declare subsystem and certification workflow management subsystem. This system can highly automize and standardize the key link of origin and product certification such as the review of filing materials, site inspection and environment detection. It can automatically generate filing materials, inspection report and evaluation report. It has the function of sending documents among certification management departments at various levels and storing them respectively. This system has speed up the agricultural products origin and product certification integration process and realized standardized and digitalized management of certification work.

Abstract: This paper studied the scheduling optimization problem of the wind power integrated system. A power system scheduling model was established aiming at minimizing the generation cost and reducing pollution. A method combined priority-list method (PL) with multi-objective particle swarm optimization (MOPSO) was proposed to overcome the blindness of particle swarm optimization (PSO) and improve the calculation speed. The priority-list method was used to sort the units. The simple economic dispatch result was taken as the initial location of particles. Adaptive mutation was introduced to guarantee the diversity of particles. The simulation result indicates that the method proposed in this paper is feasible and reasonable.

Abstract: According to the feature of numeral image of electronic balance photographed by CCD, MATLAB, especially its video image toolbox, was used to achieve the manual character region location, automatical character segmentation and automatical digit recognition of the digit image in video signals. The method is able to recognize the values in the video signals with more than 97% correctness in multiple sampling tests. However, there were also some abnormal data caused by LED light retention in the dynamic display process and recorded by high frame rate video. The problem was solved by replacing the points outside the range with neighborhood median. This method is simple, highly adaptable and reliable, thus facilitate the research on filter media surface wettability and provide a set of reference for solution this kind of research.