Advanced Materials Research Vols. 374-377

Abstract: With the flooding construction of sewage treatment plants in cities, the production capacity has being increased rapidly. This paper compares the principium and advantages and disadvantages of the treatment methods systematically and proposes to apply the way to reduce the amount of the sludge on site to reduce the production radically and achieve the completed disposal of pollutant of urban wastewater, taken into account the society, economy and environment.

Abstract: In the early research work,the concept of building energy smart grid based on natural gas based distributed energy system is proposed. For design of energy storage system applied to NDES-SG, basic principles of system design are given which follows energy saving and efficiency increasing in this paper. To interpret integration, energy saving potential and system evaluation method of NDES-SG, Combining with design principles of energy storage system, a simplified typical case system is presented. The influence of energy storage system design on the NDES-SG performance is studied taking ice thermo storage system as an example and system energy saving rate for evaluation criteria. The results show that NDES-SG with a reasonable storage system design can realize energy saving rate approximately 30% compared with NDES-SG without energy storage system. NDES-SG system energy efficiency is further improved.

Abstract: The single-component adsorption equilibrium of VOCs on activated carbon was studied. Results show that the adsorption isotherms of benzene, toluene, ethyl acetate and acetone on activated carbon all fall into type I, according with the characteristics of micropore volume filling, and the Langmuir equation proves to be the best for the fitting of experiments data. The adsorption equilibrium of different adsorbates on the same adsorbent can be predicted by the D-R equation with affinity coefficients, and the prediction precision depends on the calculation method of affinity coefficients. Of the three calculation methods, the method of molar volume is the most precise, secondly the method of parachors, and thirdly the method of molecular polarizability, with average errors 5.9%，10.2% and 27.8% respectively.

Abstract: The advantages and disadvantages of shade trees for pollutants absorption are analyzed theoretically, through actual inspect and data analysis of typical roads in Xi’an City with CO as environmental tracer. The main factor of green belt hindering the gaseous pollutants diffusion was the canopy density and not the vegetation quantities, thus over increase in green quantity is of nobenefit in urban road planting, and some ideas for green planting in urban street is recommended.

Abstract: In winter, the heated dorms have a very poor air quality. This paper intends to establish a fresh air micro-circulation in the dorm through experiments. Three different outlet configurations are designed and made. By studying the distribution of CO2 concentration, air speed and temperature, the best outlet configuration and the best installing place are determined. In a room with a temperature of 24°C, CO2 concentration of 2000ppm, the fresh air device can lower the CO2 concentration in the immediate surroundings of the student down to 680ppm, while maintain a temperature of 21°C and an air speed under 0.18m/s.

Abstract: Abstract: The application of an active zeolite barrier was investigated to improvement of eutrophication in the ancient Canal. For this, four types of zeolites (diameter: 1～2 mm) were applied in order to investage effect of the type of zeolite on N removal. The dosage of the zeolites was 1.46 kg.m-2 and the ammonium concentrations in overlying water were 3.47 mg/L. It is found that the capacity of elimination total N of the four zeolites was significant and decreased with the following order: Haiyu zeolite F1 > Aolin zeolite F2 > Natural zeolite F3 > Calcium zeolite F4. In addition, the results show that zeolite F1 and F2 belong to N inhibiting type as TN concentration of overlying water quickly reduced to 2.53 mg/L, 3.7 mg/L, and the corresponding removal efficiency of TN is as high as 56% and 35.6% after covering zeolite F1 and F2. The results indicated that the consumption rates of ammonia nitrogen in this system is greater than or equal to release rates of ammonia from sediment. However, TN concentration of overlying water still rise to high level (1.57 times of initial TN) when covering zeolite F3 and F4 (N non-inhibited type). Therefore, it is considered that the Haiyu zeolite should be the best barrier materials to clean sediment of the ancient Canal.

Abstract: Simulating the summer outdoor thermal environment of Exhibition Center in Taizhou with the improved CTTC (cluster thermal time constant) model to quantitatively analyze the effect of shading types on the heat island intensity. The results show that the effect of tree canopy is the most obvious. When the shading coverage ratio is less than 20%, the variations of average heat island intensity with the increased of solar radiation transmissivity is little, and the cooling effect is not significant.

Abstract: It has been long time for lighting designers to solve the problem of lighting in some special rooms such as high temperature and humidity rooms. In this paper, a seamless prism light guide made by extruding technique and its application in a concrete-curing room with high temperature and humidity is introduced. The illuminance level and uniformity of the room has been improved greatly by application of the guide. The average illuminance on working surface created by the seamless light guide system is 19.2 lux while that created by the original lighting fixtures is 6.2 lux. The application of the seamless light guide system also makes the maintaining work easier and safer.

Abstract: It is well-know that spatial impression is one of the important characteristics in concert halls. It is popular belief that early sound contribute to apparent source width (ASW) and late sound contribute to listener envelopment (LEV). The major concern of our study originated from the question of whether or not ASW was created only by early lateral sound energy alone. In this paper, a group of psychological experiments are performed with simulated sound fields. In the experiment, listening tests were carried out in order to exam the effect of early lateral sound energy fraction(LFE) and early to late sound energy ratio (C80) on perceived ASW. The results confirmed that C80 affects ASW.

Abstract: Effect of acidizing conditions such as hydrochloric acid concentration, acidizing temperature and acidizing time etc. on moisture adsorption and desorption properties of sepiolite in closed space at constant temperature was studied. Relationships between moisture adsorption and desorption properties and microstructure of treated and untreated sepiolite were discussed by means of microscopic testing methods such as X-ray diffraction (XRD), Field emission scanning electron microscope (FESEM)and Brunauer-Emmett-Teller (BET). The results indicated that acidizing conditions had significant effect on moisture adsorption and desorption properties and microstructure of sepiolite in closed space. The optimum acidizing condition in this experimental program was obtained by treatment with 5 wt.% hydrochloric acid at 98 °C for 9 h. Fibers in the treated sepiolite become thinner and shorter, and carbonates in layers and pore canals were dissolved. Specific surface of sepiolite treated with the optimum acidizing condition increases from 35.64 m2/g to 84.86 m2/g ,and its average pore diameter decreases from 16.84 nm to 12.68 nm.