Advanced Materials Research Vols. 610-613

Abstract: The treatment of anion surfactants in wastewater with the electrochemical reactor is studied in this paper. Factors affecting the removal rate were investigated,such as anode material、electric current density、electrolyse time、electrolyte and pH etc.At the optimal conditions of electric current density 30 mA/cm2 electrolyse time 45min, conductivity 1100µs/cm and pH 7-8，the removal rate of anion surfactants can be more than 97%. The middle outcome of the treatment is studied with UV analysis methods.

Abstract: To calibrate model parameters of tritium migration in a test site of China, an intelligent parameter inversion model based on parallel genetic algorithm is built, a forward and inverse coupling program of radionuclide migration is designed, and the values of key parameters like hydraulic conductivity, dispersity and porosity are inverted automatically on a mainframe computer, by means of abundant observation data of tritium concentration. The inversion results accord with observation data well on the whole. Compared to manual adjustment method, this method has better overall convergence, higher calculated precision and efficiency, and less manpower cost. The results show that parallel genetic algorithm is feasible and valid in application to parameter inversion of tritium migration.

Abstract: In this study, the environmental behavior of major VOCs in ambient air were investigated in urban and suburban areas in Chengdu city in the spring of 2012. VOCs samples were collected by sorbent tubes with TENAX TA, and were analyzed by thermal desorption followed by gas chromatography mass spectrometry. The most abundant VOCs were aromatic hydrocarbons (58.09%), next in order were alkanes(15.28%), esters(11.27%), aldehydes and ketones(7.64%), acids and heterocyclic compounds(3.39%), olefins(2.96%), alcohols(0.84%), amines(0.35%), ethers(0.17%). Alkanes, alkenes, aromatic hydrocarbons, esters and alcohols had the similar diurnal variation, and their concentration peaks appeared in the morning 08-09; ethers, aldehydes and ketones had similar characteristics of diurnal variation, and their concentration peaks occurred in the afternoon 14-15. This paper provided an overview and some useful information for approaching the composition characteristics, concentration levels and variation in ambient air of Chengdu

Abstract: The tunnel module of a rather simple Lagrangian model GRAL (Grazer Langrange model) has been chosen to study air pollutant dispersion around tunnel portals in Nanjing inner ring. Two points have been made to popularize GRAL3.5TM (the tunnel module of a Lagrangian model GRAL; the update was in May 2003) and assure it more suitable for the actual situations in Nanjing. One is to derive a piecewise function of the intermediate parameter ‘stiffness’. Another is to take Romberg NO_x-NO₂ scheme into account. After these 2 works on GRAL3.5TM, NO₂ dispersion from portals of all the 6 tunnels in Nanjing inner ring has been simulated. The importance of limiting urban traffic volume to control air quality around tunnel portals and roadways has been emphasized.

Abstract: Using ammonia solution to absorb CO₂ from flue gas is expected to achieve low cost and high efficiency; however, ammonia escape during CO₂ absorption limits the application of this technique. In this work, we investigated the inhibitory effect of polyethylene glycol dimethyl ether (NHD) on ammonia escape in bubbling absorption using ammonia solution. Various NHD and ammonia concentrations on ammonia escape are considered. Results show that NHD significantly inhibits on ammonia escape and enhances removal of CO₂ at the same time as well. The amount of escaping ammonia was reduced by 24.9% when 5% NHD was used. The study has important implications for application of the ammonia absorption method in carbon capture.

Abstract: Phthalates were of heath concern in groundwater and drink water. In order to understand how Phthalates were transported at different medium of the aquatic environment, adsorption experiments were conducted using quartz sand, kaolinite, and natural clay as inorganic adsorbents and sewage sludge as organic adsorbents for adsorbing Di-n-butyl phthalate and Bis(2-Ethylhexyl) phthalate. As a result, the inorganic particles displayed Langmuir adsorption characteristics. The maximum adsorption capacity is the most important parameter, varied much between the types of Phthalates than the adsorbents.

Abstract: Due to the debilitating effect of biological and mineral fouling on the optical windows, the in situ development period and data quality of moored radiometer have been very limited, especially in coastal waters. In this paper, a device for protecting the optical window of the underwater radiometer from biofouling was designed, developed and tested, and with this device, the surface of the optical window can be cleaned for several times before and after radiometric measurements to clear away the biofouling and the mineral that have adhered to the optical windows. The reliability of this device has been tested in the offing of our country.

Abstract: It is found that the increase in the number of nozzle will lead to overall pressure drop in the tower when there is no fluid column jet and in this process RNG double equation model was used to describes gas phase turbulence, by means of simulation calculation of the gas-liquid two phase flow field in double contact liquid-column tower. In the stage of liquid column jet, with the increasing of the number of nozzle pressure drop range reduced, but phase change is more apparent, flow field distribution in the tower tends to be evenly. Through the numerical simulation of the particular condition, gas flow condition was described in conditions of different nozzle number and different liquid air ratio. Calculation is well agreed with test results, which show that the model and the algorithm has good predictive and reliability.

Abstract: Artificial lakes are important parts of urban ecological construction. Combined with the local hydro-geological conditions and the topography, this paper studied the leakage problem of the proposed artificial lake, determined that the main source of leakage are reservoir bottom and by-pass dam, calculated the corresponding leakage, and finally demonstrated that the lake's storage capacity is fully capable of maintaining its ecological landscape effects.

Abstract: Water quality parameter is the basic data of the river water quality mathematical model for forecasting river water quality status. In this paper, the parameter estimation problem of the analytical model, which is used to describe one-dimensional tracing test data of river streams with tracers instantaneously injected, is converted to the function optimization problem. And particle swarm optimization algorithm is applied to solve this problem. The experimental results show that the particle swarm optimization algorithm can estimate the water quality model parameter values regardless of whether the randomly sampling data has noise.