Applied Mechanics and Materials Vols. 260-261

Abstract: With continuous consumption of proven resources, people have to turn to new resources or find new ways for prospecting. As to Yunnan Gejiu Tin and copper polymetallic deposit, deep ore prospecting may be the solution. The newly discovered copper-polymetallic deposit inside the rock of Tangzi’ao depression zone, which located in western part of Yunnan Gejiu east tin mine area, is a new type of deposit in deep ore prospecting. This kind of deposit produced in the alkali-rich, oxidizing environment, potash feldspathization is an important sign of prospecting, and a variety of metallic elements can be comprehensive utilization. It is special that potash feldspathization zone and epidotization zone alternating with each other; the phenomenon may caused by multi-period of hydrothermal fluids. By quantitative calculating the results of altered rocks and original rock samples, the author find out the migration laws of the constant elements and the main ore-forming elements and their associated elements, which provide a basis for prospecting in the future.

Abstract: A hexagonal unit cell for non-uniform electrokinetic (EK) remediation was constructed and the electric field distribution of the cell was simulated using MATLAB software. The changes of soil pH and residues of heavy metals in different parts of the cell during the permeable reactive composite electrode electrokinetic (PRCE-EK) remediation were also studied. The results showed that, the changes of soil pH, the removal of heavy metals and the distribution of the non-uniform electric field in the cell were closely related to one another during the PRCE-EK remediation. Simulation of electric field distribution could help to predict the changes of soil pH of different parts of the cell, and then help to optimize the EK remediation process. The results also showed that an acidic migration band, which could prevent premature precipitation of heavy metals to a certain extent and promote EK removal of heavy metals, was formed in the whole hexagonal cell when the cathode used PRCE during the non-uniform EK remediation of cationic metallic ions, Cd²⁺ and Pb²⁺. After 480 hours of remediation, the total removal efficiency of Cd and Pb were 89.9% and 69.3%, respectively. Further prolonging remediation and constantly replacing electrodes with new ones could obtain better remediation results.

Abstract: With the development of society, watercraft is used more and more widely. However, the stability and vibration control of watercraft have been the bottleneck of its development. In order to reduce investment cost and the accident risk, the work presents a set of design for the vibration control of propulsion motor TJDJ-1000 on watercraft. The efficiency and reliability of the proposed method are demonstrated by experimental results. Hope the work can effectively promote the rapid development of watercraft.

Abstract: This study aims to examine technical feasibility of the FLY system that was developed for control indoor temperature against change of outdoor temperature based on principles for green infrastructure. The FLY system is a control system that protects inner system from external disturbances by making transition layer. The CFD simulation was used for analyzing change of temperature at transition layer and indoor. It was analyzed that the FLY system can reduce variability of indoor temperature against uncertain change of outdoor temperature.

Abstract: Land reclamation in mine area starts later in China than developed countries, land reclamation rate is also lower, it urgently requests to explore land reclamation technology suitable for China's national conditions, in order to improve land reclamation rate and the production potential. This paper will systemicly analyzes ecological effects of mining exploitation and summarizes typical technology of ecological restoration in order to promote the further development of land reclamation in China.

Abstract: Based on referring to a large number of domestic and international literatures, the situation of arsenic pollution, the source of arsenic in drinking water and the present treatment of it were summarised. A comment on treatment for arsenic water has been made.

Abstract: In this paper the problem of road's capacity is dealt in presence of perturbations of the vehicular flow. In particular, among the different disturbing causes, it is here considered the presence of vehicles parked along the road in relation to their parking activity. Having already established the delay, caused by those vehicles leaving their stationary positions and entering the traffic flow or by those who slow down the flow to park, it is possible to evaluate the changes in time running values. Related to these times delay, the extra pollutant emissions by a given urban running fleet is also evaluated, by utilizing emission factors depending on age, type, volume capacity and engine of the vehicles.

Abstract: Five extraction methods were used to extract extracellular polymers (EPS) from Platymonas subcordiformis. Results suggested that the extraction efficiencies of EPS decreased as followed: cation exchange resin (CER) > ultrasonic extraction> heating (80°C) > EDTA > centrifugation. CER method was the most effective in the EPS extraction from P. subcordiformis with the highest amount of EPS and the lowest cell lysis, while the ultrasonic extraction method was not suitable to extract EPS for its obvious cell lysis. In addition, heating (80 °C) was used to investigate EPS formation of P. subcordiformis. Results showed EPS amount increased at the increased incubation time when the nutrients were enough whereas the ratio of EPS components remained unchanged in the growing cycle.

Abstract: Flocculation and sedimentation of fine bauxite from flotation tailing pulp were studied using different flocculants to investigate the possibility of its application. The results of this investigation indicate that inorganic flocculants of PAC and PAS have better flocculating effect than organic flocculants of PAM1# and PAM2# when keeping the original pH (7.5~8.0) of tailing pulp, however its consumption are large. It was found that the pH of pulp is important to the tailings settlement. The dosage of flocculants are greatly reduced and the velocity of floc settling is accelerated when the pH of tailing pulp is adjusted to 6.5~7.0 using sulfuric acid. PAM1# and PAM2# are effective flocculants for fine bauxite from the tailings pulp and improved the sedimentation performance compared with PAC and PAS at pH 6.5~7.0. It was also found that the flocculants can be used in combination to treat original bauxite tailing, and good sedimentation effect has been achieved, but the dosage of reagents is bigger when the organic flocculant is combined with inorganic flocculant.

Abstract: The core of eco-efficiency is to make maximum use of resources to increase the value of products or services, and to reduce the hazard to the environment as far as possible. The essence of circular economy is to improve eco-efficiency. With reference to related eco-efficiency research at home and abroad, to assess circular economy in provincial region, an eco-efficiency index system is constructed in this paper, linear weighted method is applied to evaluate eco-efficiency of circular economy of central six provinces in 2010. According to the results, the rank of circular economy development level is given in six provinces. Aiming at the shortages of eco-efficiency and developing circular economy, some corresponding policies and suggestions are put forward in six provinces.