Applied Mechanics and Materials Vols. 522-524

Abstract: In this paper, an advanced economic method is proposed in the measurement about water resources efficient (WRE), which is based on the social cycle of water resources in different economic departments and different areas. The advances of this research are as following: firstly, WRE from the economic perspective emphasizes thesocial traits of water resources which are the bases of the value of water resources; secondly, research on WRE from the economic perspective gives the special link between water resources and economy; thirdly, because the usages of water resources in different economic departments and areas are various, the measurements of Chinas WRE are run by different economic departments and various areas, and then the advance analysis are proposed. According to the research, the WRE and agricultural & industrial WRE of each province of China are calculated, and the WRE and industrial WRE decrease while agricultural WRE increase during 2001~2010.

Abstract: Water quality of Poyang Lake is facing serious threats with the quick development of Jiangxi Province. Water quality control and pollution prevention of Poyang Lake have become important problems set before Jiangxi Province. To keep good water quality of Poyang Lake, a series of pollution-preventing strategies were studied. In order to prevent point source (PS) pollution, industrial types and layout, management measures and production technique should be improved. Strategies to prevent non-point source (NPS) pollution include four aspects. First is to transform part of NPS pollution to PS pollution by rationally laying out industry system. Second is to construct spatially harmonious and reasonable landscape pattern. Third is to reform conventional agricultural production by using advanced chemical and biological technologies. Fourth is to carry out Best Management Practices (BMPs) and Low-impact Development (LID) by learning and innovation.

Abstract: The SWAN (Simulating WAves Nearshore) model was applied to study the characteristics of water waves in the Bohai Sea. The model was calibrated against both short-term and long-term field measured data from six different stations in the Bohai Sea and the computational results are in good agreement with the measured data. Then the wave process during 1999 to 2009 in the Bohai Sea was simulated using the calibrated model. The wave characteristics such as significant wave height, average period, dominant wave direction and their seasonal variations were analyzed based on the simulated results. The distributions of wave height and wave period are similar to those of the previous studies, but the wave height is slightly smaller than that given by other researchers.

Abstract: Recent researches on soil macropore and preferential flow were reviewed in this paper. Definition of macropore, causes of preferential flow, observation technologies, and preferential simulated models were introduced. Soil macropore investigated methods include dye tracing, sectioning, CT scan, tension infiltration curve, and markers tracing. Preferential flow models include two domain model and multiple domain model, two phase model and hybrid model, etc.

Abstract: A form of hyperbolic mild-slope equations extended to account for rapidly varying topography, nonlinear dispersion relation, wind input and energy dissipation during the process of wave propagation, has been derived from the mild-slope equation modified first in this paper. With the inclusion of the input of wind energy, the resultant model can be applied in some areas where the effect of wind could not be neglected. The wave-breaking mechanism which will cause energy dissipation remarkably, as well as the bottom friction, is introduced and discussed during this derivation. Since the modifying factors have taken plenty of aspects into consideration, the extended equations hold enlarged application and increased accuracy.

Abstract: The agricultural irrigation water of Kaifeng is mainly supplied by the Yellow River and the local underground water. According to the conditions of irrigation area water supply and groundwater reduction for many years, the paper puts forward the optimal allocation and the supplying water programs on using combination of surface water and groundwater. By using variable one-dimensional search technology, the nonlinear programming problem will be turned into linear programming problem. Thus, choose different decision variables and different parameters to use computing in order to get to approach the optimal allocation of water resources.

Abstract: Excessive propagation of Tubifex tubifex in eutrophic source water can result in the emergence of them in the drinking water plant, which has been a troublesome problem in recent years. Our objectives were to investigate the driving force of drift and quantify the influence of temperature and DO on the worm drift. Results showed that one of the major driving forces of the worm drift was water flow, which exhibited its effect by direct shear stress on the worm or inducing sediment suspension. The worm drift rates were increased with the decrease of temperature and DO content. The results confirmed that worm drift from sediment to overlying water, which was induced by water flow and could be influenced by temperature, DO content and sediment property was the main cause of worm pollution in drinking water plant.

Abstract: As an advanced heat metering method, on-off valve regulation method has good temperature-control and energy-saving effects. But its hydraulic regime is different from other existing systems, the conditions are more complicated and researches are not enough. There is an opinion that differential pressure valve should be used in the buildings consumer heat inlet. For all the questions and uncertainties, this article conducted researches by field test and program simulation analysis. The field test was conducted in a housing estate in Beijing, one buildings flow regulations influence on other buildings hydraulic regime was tested. The simulation was done in HACNet hydraulic simulation software. A pipe net model was built to simulate different working conditions. Both results indicate that systems hydraulic regime is stable and differential pressure valve is not necessary.

Abstract: Water consumption per ten thousand yuan GDP (WG) is an internationally comparative indicator of water use efficiency (WE), but it cannot further reveal the causes of the differences of WE. The shift-share analysis method is introduced, and the WG-shift-share analysis model (WG-SSM) is built combined with the regression model. According to the model, WE is decomposed and analyzed from the three levels of the country, the region and the industry from 1997 to 2011. The results show that: WG of the country, the region and the industry shows a significant downward trend, but WE is greatly different of inter-region and inter-industry; total shift of each region relative to the national average level is shrinking year by year, and inter-regional differences are mainly due to the competitive effect; the influence of the industrial mix effect is determined by the WE of the primary industry;the allocation effect least impacts on the differences of regional WE, but it can test the interaction between the competitive effect and the industrial mix effect, which can provide objective reference for drafting the water-saving policies and measures.

Abstract: It is significant to use different techniques to improve the overall efficiency of mine water treatment, because the utilization rate of treated mine water is low and the treating cost is high. According to the characteristics of water quality of coal mine water, the influence of the magnetic field on mine water treatment was studied in this paper in order to provide a reference for mine water treatment. It was found that magnetic field has effect on surface tension and electrical conductivity of mine water. When the magnetic field strength is less than 0.3T, the surface tension of the mine water decreases with the increase of magnetic field intensity, while the magnetic field strength is more than 0.3T, the surface tension of the mine water increases with the increase of magnetic field intensity. In the range of 0.0T ~ 0.5T, the mine water conductivity increases with the increase of magnetic field intensity and, as high as 14.8 ms/cm, then along with the increase of magnetic field intensity, the conductivity remains same. The influence of magnetic field intensity, amount of coagulant and magnetization time on coagulation were studied in this paper, and their effect were also investigated by Orthogonal test. The results show that when the magnetic field intensity is 0.35 T, magnetization time is 4 min and the amount of coagulant is 3 ml/L, the coagulation effect is the best. Under the condition, the mine water turbidity fell to 0.85 NTU from 200 NTU.