Advanced Materials Research Vols. 354-355

Abstract: In order to determine the bluff body and slitted bluff body flame stability and combustion performance, atmospheric low-speed experimental platform was used to carry out diesel fog combustion experiment for two types of bluff body, which are respectively streamlined V-form added straight channel and triangle V-form added straight channel. Results have shown that flame stability and combustion efficiency of streamlined bluff body is orderly slit width at 13mm, 6mm, 0mm and the triangular bluff body is orderly slit width at 6mm, 13mm, 0mm. Optimal combustion performance is streamlined bluff body with slit width 13mm.

Abstract: The study on transport regularity of contamination can provide theoretical evidence for forecasting the potential hazard of contamination to underground water environment and safety disposal. In this paper analytic solution of transport model on ammonia nitrogen in soil under the condition of unchangeable contamination concentration. According to model solution transport situation of contaminant on different kinds of soil which are clay, heave silt clay, silt clay and clay silt has been simulated. The results have shown that the obstruct performance to contaminant of clay is the best and the obstruct performance to contaminant of clay silt is the worse.

Abstract: The new electrospinning technology NanospiderTM offering a realistic potential for industrial production was used for creation of nanofiber sheets from aqueous solutions of partially neutralized poly(acrylic) acid with crosslinking agent. Produced nanofiber sheet was crosslinked by heat treatment. Absorption capacity and rate of absorption were tested and compared with superabsorbent particles and commercial superabsorbent fibers. The morphology of electrospun fibers was observed using a scanning electron microscope (SEM). Possibilities of fiber diameter influence were studied.

Abstract: It is significant for safe operation and energy saving to foreknow ash fusibility of coal. Ash fusibility of coal was divided into three levels according to softening temperature. The fusibility level was correlated with coal properties by a nonlinear classified model which was built using support vector machine. The model receives coal properties as input variables and would give a judgment of fusibility level as an output. Validation of the nonlinear classified model on 62 training samples yielded 100% accuracy. The prediction accuracy of 15 testing samples was 86.7%. Results indicate that the level of ash fusibility can be accurately predicted from coal properties with the nonlinear classified model.

Abstract: This study investigated the feasibility of preparing the solid biomass fuel from bio-waste material in the waste mushroom cultivation bag (WMCB) and examined whether the decaying carbohydrates due to the fungi present in the bio-waste material of WMCB affects the heating value of the solid biomass fuel. This study involves the following steps: (1) drying the bio-waste material of WMCB and the wood dust of Taiwan Acacia (TA); (2) grinding the bio-waste material of W_MCB and the wood dust of TA into the powder GP_WMCB and GP_TA , respectively; (3) characterizing the heating value of the powder of GP_WMCB and GPTA ; (4) solidifying the air-dried powder of GP_WMCB (or GP_TA ) into a biomass briquette BMB_WMCB or BMB_TA using the piston-in-mold process; (5) charcoalizing the biomass briquette BMB_WMCB and BMB_TA into the charcoal briquette CB_WMCB and CB_TA, respectively, using a home-made mechanical furnace of charcoalization; and (6) characterizing the charcoal yield, the ash and the heating value of the CBWMCB and CBTA , respectively. Both CB_TA and CB_WMCB inhere the linear relationship between the average heating value and the charcoalization temperature. The RP_HV,which indicates the reduction percentage of heating value of CB_WMCB,is less than 10%,compared with the heating value of CB_TA .

Abstract: Abstract：A field test was conducted on a photobioreactors for cultivaion of P. tricornutum for optimization cultivation conditions.Here,we use a flat-cuvette pohotobioreactor to control the irradiance, pH, gas composition combined with on-line monitoring by fluorometer and densitometer.By chosing the culture medium in containing glucose，sodium acetate and glycerol, to check for the biomass, cell concentration, biochemical substances and fatty acid content nearly three months . The results show that: Phaeodactylum tricornutum is not only photoautotroph but also mixotroph, which with selectivity for substance concentration and organic carbon sources, the optimum concentration of glucose is 20mmol/L, the optimal growth condition in 500mL flask contains that the temperature is 25±1°C, the light intensity is 50µmol/m2.s, the pH is 8.5. Whatever the carbon sources are able to promote the biomass accumulation. When the cell concentration achieve to 2.5×106 cells/mL in the end of the culture, analyzed total lipid content so as to determine the biomass accumulation and biomass variation in different growth conditions. By ultrasonic extracting and freeze drying, the total of lipid reaches 20%(dry weight); the main content of fatty acid is C16:0,C18:0,which is the better material for biodisel production.

Abstract: This study aimed to investigate the influence of the paint film thickness on formaldehyde emission rates. A small-scale environmental chamber was set up to test the formaldehyde emission from wood lacquer with different thicknesses. In all experiments, the temperature, the airflow rate and the relative humidity were the same, which were set to 23 °C, 1000 L/s, 45 %, respectively. The emission rates of formaldehyde were calculated through the double exponential decay model. Results showed that the peak concentration was dependent of the paint film thickness. The thicker the film thickness was, the slower the emission rate was.

Abstract: This paper reports the results of a study on the reason for chlorine-induced corrosion in the superheater, the factor of corrsion is caused by the chloride deposit. A three-dimensional model is performed in order to analyse chloride particles deposit in the flue-gas. The use of CFD codes for modeling of two-phase flow, it is important to know whether or not deposition will be present in some sensitive location. The RNG k-ε turbulence model and mixture model are employed in the article. The predicted results show that the volume fraction of particles phase varies along with the flow field. Chloride particles may deposit where the area of high volume fraction. Actually, under the condition of different velocity magnitude, the deposition of chloride particles is existed on the border of the baffle and at the bottom of the vessel.

Abstract: Take Changguang high-sulfur coal as experimental coal type; carry out the experiment of mineral formation rule of co-generation cement clicker on two-section multiphase reaction test stand and conduct XRD, SEM and EDS analyses on the mineral composition of the obtained co-generation clicker sample. It can be found from the experimental results that the mineral composition of co-generation clinker presents great difference with the temperature change in the furnace on the test stand; when the temperature in the furnace reaches to 1,330°C, the main mineral species in co-generation clinker sample are 2CaO•SiO₂, Q phase and 3CaO•3Al₂O₃•CaSO₄ with excellent hydration activity. Conducted thermodynamic calculation on the mineral formation reaction probably occurring in the chemical compositions of Q-phase cement clinker co-generated from Changguang coal. It is shown in the findings of computational analyses that, according to the chemical composition of clinker, the direct synthesis reaction of 2CaO•Al₂O₃•SiO₂ firstly occurs, followed by the direct synthesis reaction of 2CaO•SiO₂, the next is the indirect synthesis reaction of Q-phase mineral, and the last is the indirect synthetic reaction of 3CaO•3Al₂ O₃•CaSO₄; the final main mineral compositions of co-generation clinker should be 2CaO•SiO₂, Q phase and 3CaO•3Al₂O₃•CaSO₄. The conclusion of thermodynamic analyses on co-generation clicker mineral formation reaction basically conforms to the mineral composition in experiment of Changguang coal co-generating Q-phase cement clinker.

Abstract: The application of new single-beam normalized photo-acoustic spectroscopy in semiconductor Pb₃O₄ nano-crystals photo-acoustic spectroscopy was carried out. The measured spectra of semiconductor Pb₃O₄ nano-crystals absorption coefficient of 0.95, and then measured the semiconductor Pb₃O₄ nano-crystals powders band gap is 2.3 . The TEM image shows the semiconductor Pb₃O₄ nano-crystals are round granular structure, while the XRD spectrum indicates that the semiconductor Pb₃O₄ nano-crystals are tetragonal. The grain size measured to be about 30nm, and the average particle size after the reunion is 100nm. Compared with the micron crystal, the optical properties of semiconductor nano-crystals and nano-particle size are closely related. By changing the size of semiconductor nano-crystals, doped to change shape and optical, electrical properties of the goal. Because the defense and photoconductive materials with very special properties, they were widely used in many areas of modern technology, especially in delay bombings and stealth coating.