Advanced Materials Research Vols. 113-116

Abstract: In the 21st century, diminishing water resources have become a global concern. The Taihang Mountain area plays an important role in the sustainable development of the Bohai coastal area in Beijing, Tianjin and Hebei because of its special geographical location and features; but due to drought and deficiency of water, the Taihang Mountain area is faced with the dual problems of poverty and ecological vulnerability. It seems particularly important to develop and utilize the water resources in a sustainable manner as water is one of the key factors in promoting local economic development and improving the ecological environment. This paper investigates, from the perspective of water cycle and water transformation, the seepage recharge mechanism in slopes and river valleys, taking into account the hydrological features of the Taihang Mountain area and the hydro-geological features of slopes and river valleys in the area. Based on analysis of the formation process and characteristics of shallow groundwater resources, this paper puts forth the idea of “weak water consolidation” for sustainable development of water resources, and three groundwater development and utilization techniques in respect of seepage through rock-soil interfaces and weathered rock fissures in slopes and seepage in river valleys, offering a powerful support to the economic development and environmental improvement in the Taihang Mountain area.

Abstract: As certain refractory molybdenum with degree high oxidation and high argillization, on the premise of molybdenum concntrate recovery rate, in order to increase tenor of molybdenum concntrate, we use cyclonic static micro-bubble flotation column as concentration equipment. We used two concentrate courses to replace flotation machine eight concentrate courses. It showed that, in the condition of same recovery rate, tenor of molybdenum concntrate was 26.16%, rising by 8%. Using processes of flotation machine eight concentrate courses - concentrate regrinding - flotation column two concentrate courses, tenor of molybdenum concntrate was 39.33% and the recovery rate was of 8%. The results showed that, by increasing the degree of monomer dissociation of molybdenum ores, cyclonic static micro-bubble flotation column has higher capability in recovering and selecting ores of -400 mm size fraction. The high argillization resulting from the regrinding and unsuppressed gangue minerals are the main factors affecting the tenor of ore concentrate.

Abstract: The Circular Economy (CE) is described as changing the traditional Linear Economy to a circular one that is practiced as the “recycle use of wastes” in most developed countries. The “dilemma of ecological metaphor,” proposed both in the practices of and in academic research of CE, enlightens a strong sense for this paper to make some research about the original birth and concept of CE, the applications of CE in China and in developed countries. The paper summarizes the discussions about CE, and points out that the focal problems is how to achieve an “economic and ecological” CE, possible solutions are finally given: (1) enhance the economic foundation of theory and method in CE research (2) use market-based incentives widely on micro-behaviors in CE practices.

Abstract: Regulating the modes of production and living of urban residents in China is an important measure to cope with environmental changes, and the primary premise is to greatly improve the environmental awareness of urban residents. At present, research on resident’s environmental awareness has been carried out in many cities in China. Nevertheless, little comparative research has been carried out among cities, and there is lack of research on mutual relation and cooperation inside natural regions and the intrinsic relation in adaptability to environment. Therefore, taken the papers collected in CNKI as the data source, the paper has selected the cities in the eastern, central and western region as the objects to in-depth analysis of the present situations and the intrinsic relations between the level of environmental awareness and the adaptability to environment of the urban residents in 3 regions so as to provide reference for the government to formulate relevant management policies. As shown in the research results, the residents in the eastern cities of China have the highest overall level of environmental awareness, followed by the western cities, while that of the central cities is the lowest. In addition, the overall levels in the 3 regions differ greatly from each other. There is certain correlation between the 3 aspects of environmental awareness and 6 factors of adaptability to environmental changes. For example, Lanzhou and Inner Mongolia have the relatively lower environmental awareness with a larger population, which causes the low overall level of their environmental awareness. The educational level and energy-saving and emission-reduction level of Inner Mongolia, Jiaozuo and Suqian are relatively lower with relatively better environmental conditions, leading to relatively lower level of environmental knowledge. Urumchi and Inner Mongolia have a relatively larger population and lower economic level, which cause lower environmental awareness. The public awareness and environmental situations of Jiaozuo and Suqian are relatively better, and therefore the environmental protection there is more desirable. The fact that Shanghai has the highest education is the main reason for the highest comprehensive capacity.

Abstract: Hongfeng Lake, a man-made reservoir, is one of the five key drinking-water sources for Guiyang City, the capital of Guizhou Province in southwestern China. In the present research, the distribution and accumulation characteristics of seven heavy metals (Pb, Cd, As, Hg, Cu, Cr and Zn) in the sediment of this lake were analyzed by examining fourteen sediment samples. A method based on toxic-response factor was used to assess the potential ecological risk of these heavy metals to this lake. For comparison, the two sets of reference data representing the pre-industrial and the local baseline pollution levels of interested heavy metals were employed to derive their accumulating coefficients and potential ecological risk indices. The calculated potential ecological risk indices indicate that the lake was polluted by heavy metals, and both mercury and cadmium loadings were critical factors responsible for the ecological hazards posed to Hongfeng Lake among these seven elements.

Abstract: Rotating biological contactor (RBC) has good effect for treating wastewater, while it is rarely reported to be used for treating canteen wastewater in frigid area as in this paper. After having cultivated the biofilm, this article studied the purification effect on disposing of sewage from dinning hall by RBC and its affecting factors such as input organic loading, stages and temperature. The results indicated that even in low ambient temperature, the COD removal rate can achieve an average value of 70% and NH4-N elimination rate is over 80% in average which displayed better effects. Microscopic observations showed that there were plenty of and varies kinds of microorganisms displayed in order in bio-discs.

Abstract: Stormwater is a resource, but the traditional stormwater management practices treat it as a waste and cause many problems. Green Street is a new method to manage the street stormwater runoff through the landscape architecture application. By analyzing the origin, definition and function of the Green Street, it can draw a conclusion that the Green Street originates from America, it is a street that uses natural process to manage stormwater runoff at the source, and it can improve street water environment, create attractive streetscape, enhance neighborhood livability, etc. Also, the Green Street has five different types, including stormwater curb extension, stormwater planter, stormwater swale, pervious paving and infiltration garden. Finally, through analyzing two examples of Green Street application in Portland, Oregon, it proved that Green Street is a high effective and low-cost method to manage the street stormwater runoff. In brief, Green Street will have increasingly important significance for the street stormwater management when it is used widespread gradually.

Abstract: Cast-iron sealing devices using springs are commonly used in rotary vane steering gear. These devices have good wear resistance, long service life and maintenance-free. Finite Element Analysis of cast-iron sealing device includes contact analysis of metal materials effecting of fluid action. ADINA was used to carry on sealing mechanism of cast-iron sealing device based on taking Fluid-Structure Interaction(FSI) and contact analysis into consideration and the complex dynamic pressure metal seal with ability of automatic compensation is proposed and verified that it can enhance the sealing ability of rotary vane steering gear up to 10MPa and improve power density of steering gear which has important significance to improving controllability of ship.

Abstract: The experiment improved the synthetic methods of preparing expanded graphite, using the mixture of H2SO4 and HNO3 as the acid, KMnO4 as oxidizing agent and adopting chemical oxidization method to prepare the expanded graphite under the conditions of different temperature. We can get the optimum conditions of preparing expanded graphite by orthogonal experiment.

Abstract: Traditional leather processing posed great threat to the environment due to its numerous do-undo procedures and use of tremendous amount of chemicals, especially toxic reagents such as sulfides, lime, ammonium salts, etc. To minimize the pollution loads and avoid using unsafe substances in leather manufacturing, an enzyme-based dehairing and fiber opening, silicate pretreating, liming-deliming-bating free chrome tanning and post-tanning integrated leather processing technology has been achieved using biocatalysts for goatskins under slight basic condition. It has been found that the extent of hair removal, opening up of fiber bundles and shrinkage temperatures of crust leather are comparable to that produced by traditional methods. Scanning electron microscopic analysis, determination of physical-mechanical properties and organoleptic evaluation further verify that performance of the leathers is on par with conventionally processed leathers. Most important is that, reductions in water consumption, wastewater discharge, COD and TS loads are in the order of 60% when compared to conventional leather processing. Thus, the developed leather manufacturing technology offers immense potential for greener production of skins and hides to leather coupled with environmental excellence.