Advanced Materials Research Vols. 113-116

Abstract: In precast concrete elements manufacturing, steam-cured concrete incorporating 30% fly ash encountered the problem of a too low demoulding compressive strength. To resolve it, this paper developed a new steam-cured concrete (AFSC) incorporating fly ash and a chemical activator. Experiments were conducted to investigate the mechanical properties of AFSC. The corresponding mechanism was also discussed by testing the microstructure of concrete. Results indicate that the demoulding compressive strength of AFSC can meet production requirements, and compressive and flexure strength of AFSC at later ages increase well. Compared with that of ordinary steam-cured concrete, AFSC has a higher tensile strength, and the capability of AFSC to resist cracks is enhanced remarkably. At an early age, addition of the chemical activator can distinctly accelerate the extent of hydration of the fly ash cement systems, and thus the microstructure of concrete becomes denser.

Abstract: The rice straw particleboard was prepared using corn starch-based polymer-isocyanate adhesive, and the factors which affected the particleboard properties were investigated .The hot-pressing parameters were fixed as follows: 700kg/m3 of density, 160°Cand15min of hot-pressing temperature and time, 4.2 MPa of unit pressure. The results showed that using the acetic acid which concentration is 1% to spray the surface of straw ,the ratio of straw to wood shavings ：85︰15，the ratio of SBR/PVA：70︰30, glue- spreading 25%, the PMDI addition 3%. Using this adhesive the straw particleboard could meet the requirement of GB/T4897.3-2003.

Abstract: The removal of trichloroethylene (TCE) from water using activated carbon fibers (ACF) and activated carbon (AC) was investigated. Adsorption, as an efficient process to remove TCE from water was chosen; in particular with ACF and AC as adsorbents. The results showed that physisorption play important roles for adsorption of TCE onto activated carbon fibers, while the less important chemisorption. Langmuir and Freundlich models were then employed to correlate the equilibria data. The Langmuir model best described the AC adsorption isotherm of TCE, with R2 0.9942. Freundlich model best fitted the ACF adsorption isotherm of TCE, with R2 0.9978.

Abstract: In view of this major environmental geology problem in Dezhou City that continuous overexploiting of deep groundwater has caused he rapidly-expansion of groundwater drop funnel in recent years, the dynamic change of deep groundwater in Dezhou City was systematically analyzed as well as the evolution and development of hydrodynamic field and deep drawdown cone in temporal and spatial variation was simulated by the application of the numerical Model. On the basis of hydrogeological conditions generalized in this region, Visual MODFLOW software was applied to build mathematical model of groundwater and stimulate the seepage field of groundwater. It predicted the expansion of groundwater drop funnel and the change of underground water level under the conditions of exploitation situation and different designed exploiting volume by the model built. The depth reduction and variation of groundwater under different design schemes for pumping rate were argued by contrast analysis of the calculated results. The forecasting result under the current situation of groundwater exploitation indicates that the drawdown of water level would increase more with the continuous exploitation when the exploiting volume of current situation is 2047×104m3/a. When (time)is equal to 5a(2013), (the decline depth of groundwater) is at 4.81～22.65m and the annual deceleration is at 0.96～4.53m/a. When is equal to 10a(2018), is at 14.32～32.87m as well as the annual deceleration is at 1.43～3.29m/a, and then the average elevation of central water level of funnel is -118.06m. The forecasting results under different design schemes for exploiting volume showed that the groundwater level would continuously decrease if the present exploiting quantity is still kept at 2047×104m3/a, which the depth of central groundwater level of funnel is 144.95m in 2012. While exploiting quantity cuts down to 1950×104m3/a, the groundwater level still constantly decreases, which the depth of central groundwater level of funnel is 133.90m in 2012. Only when exploiting quantity further cut down to 1750×104m3/a, the groundwater level would never descend after 2011, and then it would begin ascending, which the depth of central groundwater level of funnel would be 120.25m in 2012. According to the model stimulation of groundwater flow and the results of water balance analysis, the exploitation project was proposed that the drawdown cone would not further expand. The key measure to protect deep groundwater resources in this region is scientific planning of underground water, and ensuring that The allowable exploiting volume in this region should be kept at 1750×104m3/a in order that it can reach a benign circle with the balance of exploitation and supplementation.

Abstract: In order to disscuss the ability of H2-production and wastewater treatment, a up-flow anaerobic sludge bed (UASB) using a synthesize substrate with brown sugar wastewater was conducted to investigate the hydrogen yield, hydrogen producing rate, fermentation type of biohydrogen production, and the chemical oxygen demand (COD) removal rate, respectively. In this paper, UASB reactor was seeded with sludge from the Harbin Wenchang Sewage treatment plant dewatered sludge. Successful start-up of the reactor was achieved within 40 days at 35±1°C.The concentration of chemical oxygen demand (COD) in influent is increased from 1100mg/L . When it reached maximum, the loading rate was adjusted in a small way and indicators such as VFA, pH and COD in effluent as well as gas production are observed. The most relevant parameters were calibrated with lab-scale experimental data. These experimental results clearly showed that, the most proper corresponding organic loading rate (OLR) and hydraulic retention time (HRT) were 6 kg/ (m3.d)（COD=6000mg/L）and 24 h respectively. Up to 85% of COD was removed and the CH4 production rate of 3.2 m3 / (m3 .d) was obtained. The produced biogas contained 72% of CH4. In the mean time, anaerobic sludge multiplies more faster and exiguous particles appeared. Granules with diameter 1-3mm.

Abstract: By a environmentally friendly method with the control of anionic amino acid surfactant N-lauroylsarcosine sodium (Sar-Na), hydroxyapatite (HAP) nanoplates were synthesized and the adsorption behavior of bovine serum albumin (BSA) were carefully studied. The products were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). Results showed that hydroxyapatite nanocrystals with lengths of 100 nm, a width of 10 nm and a high aspect ratio (10:1) were obtained. Results of UV-Vis spectrum indicate that prepared hydroxyapatite nanoplates can be effectively adsorbed BSA. The current work provides a new approach to produce biomaterials.

Abstract: The paper reviewed hydrogen production biotechnology on reactor development and design aspects. Biological hydrogen-producing reactor as acid-producing phase of two-phase anaerobic organism treatment system plays an important role in the following aspects: Reactor was developed as the follow ideas: a. CSTR-type anaerobic fermentation reactor is selected to reduce the substrate concentration in reactor and increase target product operational yield and selectivity in the reactor; b. mixture liquid in reaction area is stirred by the stirrer to reach a turbulent state in order to reduce interfacial layer thickness and temperature gradient in a floc unit particle and increase mass transfer rate; c. H2 in the particle and Liquid phase is accelerated to release to prevent accumulated H2 from bringing feedback inhibition to organism metabolism, and H2/CO2conversion to acetic acid; d. A sector turbine agitator with hoisting capacity and mixing power is selected to facilitate sludge to flow back through a effluence seam.

Abstract: Cationic surfactant, quaternary ammonium salt of lignin, was synthesis from the lignin and trimethylamine though Mannich Reaction. Then quaternary ammonium salt of lignin was used as a novel template to prepare nanostructural silica from TEOS by sol-gel templating method. After removing the template at 580°C, nanostructural silica were obtained. The results of SEM and TEM show that there were two kinds of the silica after calcined. One is 3-dimetional macroporous silica, with the pore size of 100-200 nm. The other kind of silica is nanoparticle: the particle sizes range from 20 to 200nm and the specific surface area is 387.6 m2•g-1.

Abstract: The isolation and identification of hydrogen production bacteria(HPB)with high yield and high evolution rate is an important foundation of fermented hydrogen production process by anaerobic digesting high strength organic wastewater. An improved Hungater rolling tubes technique and a plate method of culture bottle (PMCB) were employed to enumerate and isolate the anaerobes. The HPB-RL medium was designed specially for isolating and culturing anaerobic hydrogen bacteria. Culture temperature was at 37°C and 5.5 of pH. About 90 strains of bacteria were isolated, in which, a strain of the hydrogen producer with high yield and high evolution rate was isolated and named Rennanqi12. The isolates were straight rods, Grams positive, strictly anaerobic, no spore-forming bacteria, whole bacteria flagella, having capsule, 3~4 metachromatic granules. The strain of Rennanqi12 could produce hydrogen using molasses wastewater as the carbon resource. The isolate Rennanqi12 has the closest relationship with the strain C. cellulose for the 94% homology of 16S rDNA. The strain of Rennanqi12 might be a new species that belongs to a new genus. The amount of hydrogen-producing (YH2)is 1880.5ml/L medium and the maximum hydrogen-producing rate(QH2)is 28.2 mmol/g•(dry•cell)•h when R12 digested substrates were glucose.

Abstract: Four kinds of structure schemes were designed based on studying the properties, structure design principles and processing technique requirements of railway sleeper composites. The method of material performance increasing with cost level was applied in the layer jacketed type, which could ensure the performance of railway sleeper materials, as well as reduce the cost with highest possibility.