Applied Mechanics and Materials Vols. 423-426

Abstract: The paper preheated poplar and Chinese fir with microwave before dipping into fire retardant solution with the purpose of improving their permeability. The test results showed that microwave increased the routs for liquid which proved to be a feasible way to facilitate fire retardant solution to enter into wood. Fire retardant loading dosage (FRLD) and implantation depth (ID) increased for both poplar and Chinese fir. Fire retardant properties such as oxygen index (OI), mass loss rate (MLR) and flame combustion time (FCT) increased and can meet the fire retardant wood requirements defined by standard of GA/T 42.1-92.

Abstract: The penetrability of wood can be improved by alkali treatment. In this study, Chinese fir (Cunninghamia lanceolata(Lamb.)Hook) was treated by sodium hydroxide (NaOH) and sodium hydroxide-ultrasonic (NaOH/US). The NaOH solution was 3%, the impregnation time was 48h and the ultrasonic treatment time was 30min. The crystalline region of the pretreated samples was analyzed using X-ray diffraction (XRD), and the results showed that the diffractive peak of 002 crystal faces was lower and crystallinity decreased after the alkali treatment. It proved that some boding of crystalline region was cut off and area of amorphous increased. In this paper, molecular model was constructed to explain the effect of alkali treatment on wood crystalline structure.

Abstract: It is necessary to obtain a further understanding of the behaviors and characteristics of water waves in the Bohai Sea for the coastal engineering construction and environment protection in this area. The SWAN (Simulating Waves Nearshore) model, a third-generation wave spectral model on the basis of wave action conservation has been applied to study the water waves in the Bohai Sea by several researchers, and encouraging results have been obtained. However, the calibrated parameter for a wave process at an individual station does not have universal applicability for other stations, which causing problems to anyalyze the wave characteristics in the Bohai Sea. Thus, in this study how to calibrate the SWAN model in the Bohai Sea was analyzed carefully in terms of five sets of short-term wave data and one set of long-term wave data at Tanggu. It was found that wind, whitecapping, bottom mechanisms of wave source function and tide current are the four main factors in the process of wave development. A set of optimized parameters suitable for both long-term and short-term wave processes in the Bohai Sea is suggested through the sensitivity analyses of these elements. Comparisons between the simulated results and the field measured data show that the validated model can provide more accurate results for both long-term and short-term simulations and can be used to study the wave characteristics in the Bohai Sea.

Abstract: The method of retaining piles working as an anti-floating piles has advantages of lesser environmental impact, high utilization of resources and good in economic benefits, but the method effecting on underground structure was worthy of further study and exploitation. According to the practical underground projects, this paper has proposed three possible connections between underground structure, shear connectors and retaining piles. The analysis showed that the internal force and displacement of underground structural is affected distinctly by the method. In addition, characters and applicable ranges of the three different connections is introduced with the finite element analysis and calculation of stress and displacement of the main parts like base plate ,top plate ,and so on.

Abstract: The well integrity issues are more and more prominent. There is an ever increasing need for methods that evaluate and confirm the status of wells with suspect integrity. Two well integrity evaluation methods are presented. The qualitative method is based on the international published standards. And the qualitative results are obtained. For the quantitative one, the well is divided into 3 parts (well head, completion string, and well bore), and then 7 elements. The evaluation criterion of each element is set. The weight coefficient which each element affects the well integrity is obtained using the analytic hierarchy process (AHP). Then the quantitative well integrity evaluation mode is established. The well integrity risk rank can be obtained based on the well parameters. Most of the parameters can be easily got from the oilfield database. The qualitative and quantitative methods could be combined each other. The methods are tested in Tarim oil field, and the results are satisfying.

Abstract: Experiments were carried out with the simulated fluoride-containing wastewater to study the fluoride removal. The effects on the residual fluoride concentration were investigated using lime-sedimentation and coagulation/sedimentation. The results showed that the fluoride contents were among 30mg/L～50mg/L, with lime alone. The residual fluoride concentrations of 600mg/L, 900mg/L and 1200mg/L solution decreased to below 10mg/L, using Ca(OH)2+FeCl3+PAM. The fluoride concentrations of 300mg/L, 600mg/L, 900mg/L, 1200mg/L fluoride wastewater remained below 10mg/L by Ca(OH)2+PFS+PAM. Comparing two methods, the supernatant was relatively clear with Ca(OH)2+PFS+PAM, which had better settling performance. It suggested PFS and PAM has an important increase effect on the fluoride removal, and the optimum conditions: PFS was 0.1mL, fluoride-calcium ratio was 2:1.15.

Abstract: The construction of regional ecological security network system can effectively ease urban environmental pollution and enhance the comprehensive competitiveness of the region. This paper, based on Suzhou National New & Hi-tech Industrial Development Zone (SND) as a study case, intends to explore an approach to establish the ecological security pattern for rapid development region. The paper has established an ecological security critical areas composed by Mt. Dayang, Mt. Shu, Mt. Jilong, Mt. Fenghuang and other mountains as well as Tai Lake Wetland Park, three ecological corridors comprising greenbelt along Taihu Avenue, Beijing-Hangzhou Grand Canal and greenbelt along the Canal, Huguang Canal and greenbelt along the Canal, as well as urban parks such as Dabai Marsh, Mt. He, Mt. Shi and Zhengshanlu Park etc. and junctions between roads and rivers etc. to make up the ecological nodes so as to build an ecological security network pattern for SND, which is of great significance for the regions sustainable development.

Abstract: This paper aims at investigating the cointegration relationship between industrial economic growth and environmental pollutions from the timing dimension by using three types of environmental pollution indicators of industrial emissions and going further to test whether this relationship is bidirectional Granger causality. Firstly, the cointegration analysis’ result shows that the relationship between industrial economic growth and environmental quality may not meet the hypothesis of EKC curve. In the timing period analyzed, the relationship is linear and positive. Hence, promoting the relationship to be negative when only relying on self-regulation of the market will probably not be achieved. Secondly, based on cointegration test, this paper goes further to conduct Granger causality test of cointegration relationship. The result shows industrial economic growth causes pollution emission but it is not true vice versa. The reasons possibly include that that the technological progress in recent years may not embody on the reduction of pollution emission intensity, the absence of resources product market, the lack of tradable emission permits market and no effective incentives of green production behaviors of enterprises to react up on encouraging enterprises’ development. These generate external pressure to the transformation of industrial economic growth pattern.

Abstract: The objective of this study is to improve water quality resulting from rainwater purification treatment and to utilize reclaimed water purification system and high-class treatment purification system. This can be done by developing a purification treatment technique through resolution of discharged ozone problems by circulation-type of ozone treatment method with the use of a high-efficiency air-cooled cylindrical ozone generator. While the final removal rate of BOD showed the highest rate of 96% for 12g without showing a great difference for the ozone injection amount of 9g and 12g, the final removal rate of COD upon treating for 12 minutes showed 73%, 66%, 93% and 96% for 3g, 6g, 9g and 12g, respectively, exhibiting similar treatment results to that of BOD. The removal of TSS and VSS due to ozone treatment was indicated not to have occurred. Also, upon passage of the magnetized water device, the removal rate of colon bacterium and general bacteria was shown to be about 35%, while a high removal rate exceeding 70% was indicated during the initial 3 minutes. Upon final treatment for 12 minutes, sterilization power above 99% was exhibited. Upon treatment using the magnetized water device and the OH^- radical generator, not only dissolved suspended materials but also excellent sterilization power appeared to be identifiable.

Abstract: Objective of the present study is to derive appropriate study factors upon introduction of purification technique with mounting of multi-type of electrical membranes in an industrial combined with contaminated underground water. For reaction times of 540mins, removal rates according to the strength of voltages were calculated and optimum operating factors of the electrical membrane were derived according to treatment conditions per concentration of electrode liquid using electrical membranes. The removal rates as a function of voltages were shown to be 88% at 15V for Ni, 65% and 68% at 15V and 20V, respectively, for Cr. In the comlex modulation electromagnetic field, Cr showed the removal rates of 80% and 85% at 15V and 20V, respectively, while Ni showed the removal rates of 94% and 97% at 10V and 15V, respectively. When the concentrations of electrode liquid (Na₂SO₄) were varied upon electrode membrane treatment, the removal concentration for 0.5% was 1.8mg/l in the case of 20V resulting in the removal rate of 91%. In case of 1% of electrode liquid (Na₂SO₄), the final concentrations at 15V and 20V were shown to be below 1mg/l in both cases, and high removal tates above 98.9% could be obtained in the treatement with combined application of the electromagnetic field.