Applied Mechanics and Materials Vols. 71-78

Abstract: Wastewater composition and characteristic in a northern university of China were analyzed according to the sampling and analysis of sewage discharged from the different function units. The sewage discharge quantities and principles of different time points and seasons were monitored. The results showed that the concentrations of pollutants in northern campus sewage changed in a certain pattern with the alteration of sampling time and season. Different function units had significant effect on wastewater composition. The influence degree depends on the concentration of characteristic contaminant. The study will helpful to design different campus sewage treatment system due to the principle of partition and dispersion.

Abstract: Samples of road dust were collected in Changzhi, Taiyuan and Jincheng in Shanxi Province, the characteristics of the chemical composition of fine particles (diameter ≤ 10μm)and the chemical profiles of road dust obtained from different cities were analyzed, the "double source apportion" technology was applied to identify the source of road dust . Results show that: the chemical profiles of road dust vary significantly in different regions, however, all contain a high percentage of Si, Ca, Al, TC and OC, with the highest content of Si; Road dust originates mainly from soil dust, smoke and dust from coal and cement dust, and their contributions to road dust are 50%,25% and 15% in Changzhi ,47%,26% and 20% in Taiyuan,48%,21% and 22% in Jincheng, respectively.

Abstract: This paper dealt with the influence of various factors on As(Ⅲ) and As(Ⅴ) removal using ferruginous manganese ore, including environmental factors (temperature, time, light, pH) and coexisting ions(HCO₃^-,CO₃^2-,Cl^-,HPO₄^2-,SiO₃^2-,SO₄^2-,Mg²⁺,Ca²⁺,Fe³⁺). The comprehensive influence of various factors was also studied in orthogonal experiment. The results showed that the removal efficiency of As(Ⅲ) was up to 90.26%, while As(Ⅴ) was only 79.88%, under the conditions of that manganese ore dosage was 0.1000g per 50ml polluted water, reaction time was 1h, pH was 3.05, the concentration of arsenic was 204.45ug/l. Lower pH could achieve higher removal efficiency. Illumination was little beneficial to the removal efficiency. SiO₃^2-, HPO₄^2-, CO₃^2- and HCO₃^- could reduce the efficiency, due to competitive adsorption and electrostatic repulsion. The results of orthogonal experiment indicated that SiO₃^2- and HPO₄^2- were the greatest competitors with arsenic for adsorptive sites on the manganese ore, while temperature and time had no significant effect on arsenic removal.

Abstract: Effects of different tillage systems on organic carbon and carbon management index (CMI) in paddy soil of long-term experiment site (since 1990) were studied. The experiment included three tillage treatments: conventional tillage with rotation of rice and winter fallow (CT-r) system, no-tillage and ridge culture with rotation of rice and rape (RT-rr) system, and conventional tillage with rotation of rice and rape (CT-rr) system. Soil labile organic carbon measured by oxidation of KMnO₄ respond rapidly to carbon supply changes, and it is considered as an important indicator of soil quality. Compared with CT-r system, long-term RT-rr system significantly increased total organic carbon and labile organic carbon in surface soil (0-10 cm and10-20 cm). The proportion of labile organic carbon to total organic carbon under RT-rr system was higher than other tillage systems. The carbon management index (CMI) is derived from the total soil organic carbon pool and carbon lability and is useful to evaluate the capacity of management systems to promote soil quality. The CMI increased in each layer under RT-rr system, while it decreased under CT-rr system. This indicated that conservation tillage improved the capacity of the management system into promoting soil quality in Sichuan Basin of China.

Abstract: Green roofs are a passive cooling technique that stop incoming solar radiation from reaching the building structure below. Many studies have been conducted over the past 10 years to consider the potential building energy benefits of green roofs and shown that they can offer benefits in winter heating reduction as well as summer cooling.With review and summarized the description of its functional traits in our country, this paper discuss the necessity to carry out the research on the functional traits of green roofs, and gave some suggestions about how to do this.At last, we propose the estimate method for the cost of green roofs construction project and green roof’s economic value and ecological benefit.

Abstract: In this research, the dissolved air flotation (DAF) were tried to treat drinking water to replace traditional sedimentation technology. Experimental study of sedimentation process and DAF was carried out in a jet tester and a glass bubble column respectively. The experimental results demonstrated that the indicators of water quality such as turbidity, chromaticity and COD_Mn after two processes decreased firstly and then increased with the PAC-dose increasing, and 7.41 mg Al L^-1 was the optimum PAC dosage. Moreover, with the optimum PAC dosage, water quality after DAF proved much better than that after sedimentation process. As a result, DAF is a more effective technology to treat the reservoir water with low temperature, low turbidity and high NOM.

Abstract: In this study, cost-benefit analyses based on life cycle assessment is applied to optimize the recycling of processing water for semiconductor factories. A representative 8-inch semiconductor wafer manufacturing plant is selected and seven existing or potential processing water-recycling sources were set, reverse osmosis (RO) reject, ultrafilter (UF) reject, multimedia filter (MMF), on-line analyzer drain, cation/anion (C/A) filter and merry-go-round (MGR) filter backwash water (including C/A sensor drain), wafer process organic drain and wafer process inorganic drain, marked as point 1 to 7, respectively. To sort the water-recycling sources in ascending order of the results of life cycle cost analyses, they were point 4, 5, point 2, 3, point 1, 7 and point 6, with life cycle the cost about 100,000$, 350,000$, 1000,000$ and 2000,000$, respectively. The order changed when they were sorted by their unit recycling-water costs; that was point 1, 2, point 5, point 3, 4 and point 7, with the unit recycling-water costs 0.2$/ton, 0.3$/ton, 0.4$/ton and 0.5$/ton, respectively. The analyses also evaluated the water recycling practice for various assumed unit tap water price. The optimal processing water recycling strategies based were proposed and corresponding optimal water-recycling rates were 24%, 64%, 81%, and 85% for water price 0.373$/ton, 0.578$/ton, 0.75$/ton and 0.945$/ton, respectively.

Abstract: The global environment is deteriorating gradually after the middle of the twenty century, the global aims at sustainable developments and positively research related policies and programs. SBTOOL is frequently referred to as the research tool of case assessment by many countries in International Conferences of sustainable development; SBTOOL is recognized internationally as assessment tool contributable to the development of sustainable buildings in various regions due to its elastic adjustment. Thus this study uses SBTOOL to access the relevance between EEWH and the results of assessment on the examples by SBTOOL based on 10 examples of the residence buildings granted as Taiwan Qualified Green Buildings, analysis the influence of the “Duplex and Single-family Houses” and “Architectural Floors” on the result of the assessment to provide reference for the international integration of Taiwan sustainable buildings.

Abstract: Bridge engineering concrete’s Freeze-thaw damage is the main durability diseases which take place in the service process of north China. Aiming at the Songhuajiang Highway Bridge being located in the cold-warm alternant area, According to this environmental characteristics, a batch of concrete samples were made in the construction site by using Material and ratio of the Bridge’s practical construction, they were shipped back to the laboratory and then were used in freeze-thaw test and carbonization test under the influence of freeze-thaw. Obtained the dynamic elastic modulus and compressive strength variation regulation according to the freeze-thaw circles of the concrete specimens. Analyzed the relation between laboratory experiment and field atmospheric exposure test, the paper constructs the durability degradation appraising model and predicts the maintenance-free life of Songhuajiang Highway Bridge. It has important meaning for the maintenance and repair measures in the process of this bridge.

Abstract: The study discusses the simulation analysis based on the modflow software. Generalize body site, zone and boundary conditions of simulation, make a finite element model based on the geology of the Collapse of Lot 110 , Dalian Metro. Determine the accuracy of the simulation results based on the comparison between the test and the field measurement data. And then predict the flow of groundwater and the penetration. Base on the software simulation of the surface displacement and field observation wells pumping records, to calculate the water surface elevation and the elevation, the general trend of measuring is same and the values are ​​consistent. Prove the necessity of the injection that is used in the accident.