Applied Mechanics and Materials Vols. 260-261

Abstract: Early warning system of water resources security is a multi-level and complex system made of many factors. By analyzing current situation of water resources security early warning, operating mechanism of water resources security early warning system is put forward. Logic, time and knowledge related to operating mechanism are discussed. For early warning threshold decision is one of key technologies in water resources security early warning, warning threshold decision and warning degree classification of water resources security early warning are set forth. These methods are systematic method, control chart method, catastrophe theory method and expert decision method. Adopting the water resources security early warning system, situation can be analyzed and predicted promptly and effectively.

Abstract: Life cycle assessment is a technique to assess potential environmental impacts associated with all the stages of a product, process or service. This paper introduces life cycle assessment into the full process of agricultural circular economy. There are increasing environmental risks associated with agricultural circular economy; however, no appropriate assessment and analysis techniques on environmental impact are available. Due to the lack of special life cycle assessment database and available methodology in agricultural circular economy, we proposed a life cycle assessment technical framework with emphasis on problems associated with traditional agricultural circular economy life cycle assessment. This paper is aimed to produce reliable information on the environmental impact assessment for agriculture policy-makers, producers and consumers to help them choose sustainable development agricultural products and processes.

Abstract: A simulation training system of multi-effect seawater desalination is helpful for research and training. A method of organizing the virtual space and models into a hierarchy tree was proposed, according to their topology relationship. The simulation model of seawater desalination plant was given, and the PID control system was designed. According to different kinds of operation modes, the meaning of gestures in different scene context was analyzed. A context-sensitive fast algorithm was proposed to accelerate the collision detection. A simulation training system of multi-effect seawater desalination is successfully realized and applied in worker’s training.

Abstract: The removal of heavy metal ions is very significant for the restoration of ecological environment and recycling utilization of water resources. By using the advanced treatment technology for wastewater such as strengthening coagulant, adsorption by modified zeolite and the combination of both，respectively, the influence of different parameters like adding dosage of coagulant and flow rate of raw water on the removal efficiency of zinc and cadmium ions from wastewater was investigated, and the operating conditions were optimized. The results showed that the removal efficiency of zinc and cadmium ions from wastewater both improved in the combination process of strengthening coagulant and adsorption by modified zeolite, and they increased by 5.8% and 2.8% respectively than that of strengthening coagulation process alone, while the removal efficiency of zinc ion increased by 4.5% than that of adsorption by modified zeolite process alone. The removal efficiency of zinc and cadmium ions both gradually increased with increasing adding dose of coagulant, but they decreased when flow rate of raw water increased. In the combination treatment process of strengthening coagulant and adsorption by modified zeolite, the suitable operating condition were selected as 8 of initial pH of wastewater, 18 mg/L of polyaluminium chloride (PAC), 9mg/L of polyacrylamide (PAM), 150g of modified zeolite and 20L/h of flow rate of raw water.

Abstract: The environmental similarity in this study is the special part of ships' ballast water risk assessment of environmental similarity in ships' ballast water risk assessment. The environmental similarity refers to the degree of similarity between two or more ports. For the study of ships' ballast water, the main consideration is the degree of similarity between the port seawater, in the process of the degree of similarity to the seawater, choosing temperature, salinity, pH, DO, DIN, DIP to calculate the environmental similarity. Firstly, the two calculating environments similarity methods (angle cosine method and based on the concept of ORDR (overlap ratio of data ranges) environmental similarity calculation method) are described and discussed. And analyze their problems. Then, propose a new method for calculating the environmental similarity.

Abstract: The papermaking black liquor of one Paper Mill in ChaoZhou, GuangDong Province was treated with the wet oxidation method and the influence on treatment effect with the reaction pressure was researched. Experimental results showed that the papermaking black liquor was treated by the wet oxidation method; the treatment effect was showed upward trend with the increase of the reaction pressure, and the reaction pressure of 3.5 MPa is appropriate. The papermaking black liquor was treated by the wet oxidation method, the influent pH about 8.00 showing weakly alkaline basically. The decolorization removal and turbidity removal first increases and then slightly decreases basically with the increase of reaction time.When the reaction time is 60 min, the treatment effect is overall best. The decolorization removal can reach 61.1 % and the turbidity removal can reach 73.8 %.

Abstract: The northeast of China with rich sources of corn straw resources as raw materials, we take use of multi-component solvent as the liquefaction. Ethylene glycol, polyethylene glycol (200) and glycerol，the three kinds of solvent mixing for liquefacient. We got the optimum process conditions, which is reaction temperature is 160 °C, reaction time is 60 minutes, catalyst amount to total liquefied agent is 3%. On the product analysis shows that the solvent liquefied corn straw can be effectively degradation. The results indicated that the liquefaction products contains phenols, aldehydes, et al, such as carboxylic acid group material, which can be converted into the corresponding ether, ester etc polymer compound that can be used in plastic, building heat preservation etc partly replace at present, these resources products from petrochemical. Straw liquefaction can reduce dependence on fossil energy, and make up for a single energy products of the shortcomings of the economy, which have great significant strategic.

Abstract: Focusing on the water shortage and water stress during the construction period of Zhidan energy chemical industrial park, the optimal allocation of water resources in Zhidan was conducted, in order to guarantee the water demand of the energy chemical industrial park. The optimal allocation of water resources is based on the advanced investigating and analyzing on the potential of four kinds of available water in this industrial park (surface water, underground water, the rain-flood and the recycled water). As well as the principle of optimal allocation is to reduce the conventional water exploitation and to increase the unconventional water resource utilization. The study result shows, the recent total water resources in this park is 12.39×10⁴ m³/d and the forward total water resources is 13.39×10⁴ m³/d, which can meet the requirement of both recent and forward water consumption for this park(4.40×10⁴ m³/d and 5.16×10⁴ m³/d). The optimal allocation of water resources program is to achieve the goal of reaching a recent water supply of 4.5×10⁴ m³/d, among which the underground water is 0.95×10⁴ m³/d, the surface water is 3.0×10⁴ m³/d, the recycled water is 0.5×10⁴ m³/d, the rain-flood water is 0.05×10⁴ m³/d. While for the forward water supply of these 4 available kinds of water are 1.45×10⁴ m³/d, 3.0×10⁴ m³/d, 1.0×10⁴ m³/d, 0.05×10⁴ m³/d respectively with a total supply of 5.5 ×10⁴ m³/d.

Abstract: Generally speaking, after the rapid economic development in base of the rich resources, there will inevitably come with the economic downturn which caused by resource exhaustion in resource-based cities. It will be difficult to avoid the phenomenon of “urban decay with the depletion of mineral”, if corresponding countermeasures can not be made timely. In this thesis, we will analysis in-depth to find constraints on the sustainable development in these cities, and point out that we can achieve the sustainable development by the adjustment of industrial structure in these cities. Meanwhile, we will expound and prove the possibility to overcome these constraints from the internal and external of these cities. Finally, we come to the conclusion that it is an inevitable choice to achieve the sustainable development of resource-based cities by the adjustment of industrial structure.

Abstract: In order to analyze the impact of the green tide (Ulva prolifera) on the phytoplankton community, eight surveys were conducted in the sea area of Haiyang, Yantai and Rizhao from July 2008 to September 2008. In the surveys, 62 phytoplankton species were identified, belonging to 4 phyla, 31 genera. The average abundance of the phytoplankton was 3.49×10⁶ cells/m³(1.59×10⁵–1.28×10⁷ cells/m³), with a proportion of 92.02% diatom and 6.70% dinoflagellate. The phytoplankton abundance gradually decreased from the inshore area to the offshore area. When green tide occurred, the dominant phytoplankton shifted from Chaetoceros curvisetus, Ceratium tripos, Chaetoceros affinis, Skeletonema costatum to Thalassionema nitzschioides in Haiyang, Yantai and Rizhao. The varied nutrients caused by green tide could be an important factor for the dominant species shift in the phytoplankton community.