Advanced Materials Research Vols. 250-253

Abstract: The discharge of urban sewage and agricultural non-point source pollutants is the main reason causing eutrophication in gullies in most cities of northern China. Based on a careful analysis on the ecological structure and ecological characteristics of a gully, this article preliminarily studies the interception and degradation mechanisms of nitrogen pollutants by the gully. Meanwhile, to take gullies in Changchun as the object of the study, this article carries out an experiment on the interception effect of nitrogen pollutants by gullies. This experiment respectively establishes a control section in the upper and lower reaches of a gully, and takes water samples four times in each section from May to August to determine total nitrogen, total phosphorus, nitrate nitrogen, ammonia nitrogen and salinity. The result shows: the gully plays some role in the interception of pollutants; total phosphorus accounts for the largest interception in pollutants in the experimented gully section, with the relative interception rate of 27.46%, followed by ammonia nitrogen, with the interception rate of 21.80%, which is the result of the combined effects of aquatic plants, microorganisms and sediment in the gully.

Abstract: A spectrum analysis is one in which the results of a modal analysis are used with a known spectrum to calculate displacements and stresses in the model. It is mainly used in place of a time-history analysis to determine the response of structures to random or time-dependent loading conditions such as earthquakes, wind loads, ocean wave loads, jet engine thrust, rocket motor vibrations, and so on. The paper is to analysis displacements and stresses of a cable-stayed bridge that is used with a known earthquake spectrum.

Abstract: The impact of the campus environment is an important factor in the quality of college campus, it is closely related to the school's image, brand, honor, and quality. Therefore, building high-quality, high-quality university campus landscape has drawn attention of colleges and universities increasingly. In order to build a campus environment with good ecological environment, beautiful landscape, vibrant and rich cultural atmosphere, we need to understand the nature of university landscape planning design. With the purpose of in promoting and exemplifying the university landscape planning and design, the thesis will illustrate from the following aspects: the design of campus landscape is to build an organic growth, carrying the material carriers the school even the human spirit the cities, and with the responsibility of integrational function.

Abstract: Landscape design of reservoir buildings is an important part modern hydraulic engineering. Besides specific functions, all buildings in the reservoir should be carriers of histories, cultures, ethical customs and modern technologies. In the present paper, engineering characteristics of Kizil reservoir, combined with specific human geography environment was comprehensively analyzed based on principles of landscape. Corresponding concept, design and program of landscape are proposed, so as to provide an important foundation for the construction of reservoir landscape ecology and development of local tourism resources.

Abstract: ‘Diversion enter city’ is a fundament in constructing ‘Waterfront City’. It plays an important role in enriching the urban landscape level and improving the quality of the environment and urban quality. Associated with the planning project of Mengjin channel passing through Wujiaqu city, the present paper suggested a planning idea of ‘landscaping by the water’ by means of ‘Diversion enter city’, on satisfying the requirement of flood control. Choosing history and culture as landscape design elements, the landscape units became the carriers of urban culture. The idea provides a theoretical guidance and technical support for planning landscape ecology, constructing eco-city garden, building civilized city, improving the quality of life, speeding up the economic development of this city.

Abstract: Based on the equivalence principle, the concentrated vertical load which acts on the Continuously Reinforced Concrete Pavement(CRCP) transverse crack is translated into the equivalent half-wave sine load by Fourier transform. According to the translation principle of the force, the half-wave sine vertical load acting on the CRCP transverse crack is decomposed to the half-wave sine vertical load and the torsion force acting on the center of CRCP. Lastly, the deflection, torsional displacement and stress formulas of CRCP under the concentrated vertical load with hollow foundation are put forward, which is on the basis of the small deflection theory of elastic thin plate and torsion theory. The results show that increasing the slab thickness is the most effective measure to reduce maximal deflection, distortion displacement and stress of CRCP concentrated vertical load with hollow foundation.

Abstract: The Golmud-Lhasa section of Qinghai-Tibet railway strides over the Tibet Plateau hinterland, ‘the roof of the world’, which traverse to typical ecosystem, as desert, alpine grassland, plateau alpine meadows, swamp wetland, and permafrost zone. Due to the special ecological property of the Tibet Plateau, it become the more river source of the China, even of South Asia, it plays an irreplaceable role of ecological function of the China and the South Asia. The human actions and climatic changes have contributed to the environmental becoming worse and worse. Fragile ecological environment once destroyed, it recovering is very difficult or unrecoverable. The railway construction, it inevitable involved in environmental problem, therefore, how to implement ecological environmental protection is one of the most major subjects of the railway construction. This paper analyzed the adverse effect of the ecological environment in the railway construction period and summarizes the protection measures of ecological environment that had taken in the railway construction. Given the example of the human economic development and the environment protection could be harmonious and sustainable developed in the Tibet Plateau, also show the most precious experiences for the ecological environment protection of the project construction in the plateau zone.

Abstract: As a traditional disinfection method, chlorination disinfection is used generally in the plants ,however, disinfection by-products (DBPs) during chlorination process generate accordingly. Nitrogenous organic compounds is a kind of important precursors of DBPs. Haloacetic acids (HAAs) is one kind of the main DBPs. Aspartic acid (Asp) is one kind of elementary amino acids,which are typical nitrogenous organic compounds.In this paper, the formation characteristics of HAAs by Asp under different chlorination disinfection conditions have been researched, such as reaction time, chlorine dosage, pH, temperature and Br^- . The results show that the yields of dichloroacetic acid(DCAA) and trichloroacetic acid(TCAA) are both increased with the reaction time increasing,and the formation rates is accelerated at the initial period; With the increase of chlorine dosage, the yields of DCAA and TCAA increased; The yield of DCAA and TCAA are both low in the acidic condition and high in the conditions of neutral and alkaline conditions. The yield of DCAA and TCAA increased with the increase of temperature. When there is Br^- in water, bromided-HAAs can be formed.The total HAAs yield and BIF both increase with the increase of Br^- concentration. The HAAs constituents contain DCAA,TCAA,BCAA,DBCAA, DCBAA, DBAA and TBAA. At low Br^- concentration,the order of HAAs constituents yields is DCAA>BCAA>DCBAA>TCAA>DBCAA> DBAA>TBAA.

Abstract: This study evaluates the influence of an extensive green roof on runoff quantity dynamic during individual rainstorms in Central China. Controlled experiments on a simulated extensive green-roof plot were carried out firstly to produce a unit hydrograph (UH) by the methods of S-curve linearization treatment and curve fitting. Then in situ tests were conducted to compare runoff quantity per minute from the green roof plot and a conventional roof plot to verify the obtained UH and compare their runoff quantity dynamic during two rain storms in the year of 2009.The obtained UH is able to predict accurately peak flows and runoff volumes for any rain input. When the initial water content of the substrate was dry, the 7 cm thick green roof can delay the runoff initiating for nearly 8 minutes, lower runoff peak and volume by about 50% compared with conventional roof during a 10.1mm rainstorm on 7 June; and even when the substrate was wet, the extensive green roof can detain runoff effectively by 129 min longer than conventional roof and thus lower the peak flow of runoff by 43% during a 6.3 mm rainstorm on 12 March.

Abstract: Rural landscape elements reflect lifestyle and cultural awareness of local residents, people can capture the characteristics of cultural identity within the territory clearly; the other hand, people can live their own lives, accurate positioning of space activities, and handle the relationship between culture and nature on the sustainable development of modern town planning and design of great significance. The article is gonging to focus on the local environment and landscape elements to create a small town in the theoretical basis, practice application methods were studied.