Advanced Materials Research Vols. 374-377

Abstract: The building energy saving, a leading trend of building development, is associated with the sustainable development strategy. First of all, the paper introduces the energy consumption situations of large public buildings in China. Next, it puts forward some proposals about energy saving, hoping to be valuable for improvement of the buildings in the aspect of energy saving .

Abstract: In order to establish and analyze the categories and application status of energy-saving products of building envelope in northern China, especially in severe cold and cold climate zones, the categories and statistic data of building envelope in northern China is gained in the classes of wall, door and window, through the way of referencing from the relevant literatures and data, investigating and visiting companies. The comparison and analysis of the date shows that the building envelop in northern China can basically meet the design requirement of heat preservation and energy-saving in severe cold and cold climate zones. Traditional products of building envelop are suitable for the multiple requirements and energy-saving need of modern architecture. Further research and development of new materials and technologies is needed but the restrain and lack of standardization in existing market should also be taken into consideration. The categories and statistic data in this paper play a reference role to other scholars and designers for researching the building envelop in severe cold and cold climate zones.

Abstract: In temperature and humidity independent control system, although the heat storage capability of the concrete ceiling is not big, for energy-saving building with small air-conditioning load, its potential of operating cost’ saving is not negligible. Based on an energy-saving dwelling building’s typical room in Wu Han, China, this paper dynamically analyzes the room’s load and concrete ceiling’s radiating capability, get conclusion that: according to the peak-valley electricity price and reasonable intermittent operation strategy, the temperature control system can save cost by 16.6% in summer, 27.3% in winter.

Abstract: By using parallel process of photocatalysis-biological contact oxidation, a research on the pretreatment effect of micro-polluted raw water was conducted. The result indicates that the changes of HRT and the initial concentration take significant impact on the removal of NH₃-N. 60min is the best residence time for the pretreatment. Once the thickness of composite media is 120mm, the removal efficiency of COD_Mn may reach as much as 15.55%, while the average removal efficiency of turbidity is 20%. Since the nitration reaction consumes certain amount of alkalinity, the pH value of outlet water is lower than inlet water. When employing parallel process, biological oxidation and photocatalysis are performed and finished in the same reactor simultaneously, conducing to maintaining a moderate level of the removal of CODMn and NH₃-N. All these are of reference value for its application in practical engineering projects.

Abstract: High photocatalytic activity TiO2 photocatalysts were prepared using titanium(IV) sulphate as the precursor by liquid-phase precipitation method. X-ray diffraction and TEM were employed to characterize the morphology, structure of the photocatalysts. Photocatalysic activity of TiO2 prepared by this method was investigated using photocatalytic degradation of methyl red (MR) under UV and visible-light (VL) irradiation as the model reaction. The results indicated that the highest catalytic activity TiO2 catalyst was prepared under 700°C calcination for 4h. The optimum decoloration rate of simulated dyeing wastewater for MR reached to 95% and 98% after UV and visible-light illuminating for 30 min and 140min respectively.

Abstract: A new type of a non-light concentrating solar photoreactor with immobilized catalyst was developed, where a flat and transparent structured box made of polymethylmethacrylate comprised the main body, and immobilized TiO2 membrane supported on glass fiber net with sol-gel method was used as catalyst. Phenol was used as model pollutant to evaluating the device performance. The limitation of mass transfer was diminished when the circular flux exceeded 2L/min. The apparent reaction kinetics was first order with respect to the phenol concentration, and the apparent kinetic constants decreased with the increase of initial concentration. The linear dependence between apparent reaction rate and radiation density flux was found from 12.8 to 47.6 W/m2. The new reactor, which treated phenol in tap water with high efficiency, has a promising prospective in real drinking water treatment.

Abstract: The phosphate removal and recovery from lower concentrated phosphate wastewater with the quartz sand, ceramsite, blast furnace slag and steel slag as seed crystals were investigated. The results showed that the steel slag performed a better phosphate removal performance than the other threes. The phosphate crystallization occurred under the reaction conditions of Ca/P 2.0, pH 9.0, phosphate concentration 10 mg/L and reaction time 12h. The steel slag could be employed as an effective seed crystal, of which the phosphate concentration decreased drastically in 12h and almost had been removed completely in 48h. The XRD analysis showed that the main crystallization products were hydroxyapatite (HAP) and the crystallinity increased with the reaction time.

Abstract: Nano-sized titanium dioxide in aquatic environment poses potential impact on environment and human health. In this research, the impact of pH value, humic acid (HA) and divalent cations (Ca2+) on the stability of titanium dioxide nanoparticles(NPs) in the aqueous enviorment was investigated using a batch test. The results showed that the particle size of TiO2 NPs was not sensitive to the pH value but presented inversely proportional to zeta potential. The TiO2 NPs become more stable along with surface zeta potential, accompany with small particle size and high dispersion. In the presence of HA, the particle size was smaller and TiO2 NPs could be stabilized. This might be synergistic effect of the ligand exchange and electrostatic force. Meanwhile, NPs particle size increased with the addition of Ca2+ and the stability of TiO2 NPs became decreased.

Abstract: In our study, a new kind of material for Copper (Cu2+) absorbency was prepared by melt blending with EPDM as the matrix and modified zeolite as the filler. In order to overcome this obstruction, PEG-2000 was used as pore forming agent. By calculating, trial parameter n was 1.9, so, the composite was easy absorption. By SEM and XRD measurement, it was confirmed that the composite was more suitable as filler than the original zeolite and the acid modified zeolite. It can be showed that the pore forming agent adding was necessary and effective for the absorption by SEM micrograph of suction passage in EPDM and the composite.

Abstract: A new kind of prism light guide is introduced in this paper. The guide is seamless and made by extruding technique, which makes it has lower cost. The cost of the guide is only about 15% of the price of prism films. The guide transport light by total internal reflection and the light-transporting principle is described in detail in this paper. In theory all light would be transported by the process of total internal reflection but irregularities in the guide cause a small proportion of light to leak out the guide. This effect can make the guide glow and for this reason the seamless prism light guide acts as both a light transport and emission device. The guide can be used in lighting or daylighting of underground buildings and windowless buildings, or buildings in which inflammable and explosive products are manufactured. It can also be used in nightscape lighting as a decorative lighting fixture. In this paper, the application of the guide in a concrete-curing room is introduced briefly.