Applied Mechanics and Materials Vols. 295-298

Abstract: Production of porous and light-weight thermal insulation materials with reduced thermal conductivity and raised porosity were accomplished using sludge (SL) and sugar filter mud (SFM) as pore-forming agent respectively and composite pore-forming agent (CPFA) at different sintered temperature and holding time. The results of thermal insulation materials with flexural strength 7.65 MPa and thermal conductivity 0.056 W•m^-1•K^-1, obtained at 1000 °C for 0.5 h show that its the porosity factor raised to 40.60% and the bulk density of the materials decreased down to 1.265 g/cm³ using CPFA, closed porosity and dense structure in sample was observed by SEM

Abstract: In the paper, we theoretical analysis the gas-particle flow behaviors in the drying chamber. Then establish a small experimental device and conduct a comparative fluidization experiment with superheated steam and hot air, which the dried rapeseed particles are the experimental material. The critical fluidizing velocity of the rapeseed particles in superheated steam is 1.26 m/s in the experimental condition. The experimental results show that the inlet operating flow velocity of superheated steam fluidized bed drying is greater than which of the traditional hot air fluidized bed dying under the same conditions.

Abstract: The article deals with determination of spontaneous ignition temperature and flash ignition temperature of polymeric materials and monitoring of mass loss rate during their degradation. An experiment was conducted in accordance with standard STN ISO 871: 2010 Plastics. Determination of ignition temperature using a hot-air furnace.

Abstract: Rhodamine B thiohydrazide (RBS) was firstly employed as turn-on fluorescent probe for hypochlorite in aqueous solution and living cells. It exhibits a stable response to hypochlorite from 1.0×10^-6 to 1.0×10^-5 M with a detection limit of 3.3×10^-7 M. The response of this probe to hypochlorite is fast and highly selective compared with other reactive oxygen species (such as ^.OH, ¹O₂, H₂O₂) and other common anions (such as X^-, ClO₂^-, ClO₄^-, NO₃^-, NO₂^-, OH^-, Ac^-, CO₃^2-, SO₄^2-).

Abstract: A rapid method for determination of formaldehyde in paint and indoor air by flow injection spectrophotometry based on the catalytic effects of formaldehyde on the oxidation reaction of methyl orange by potassium bromate in sulfuric acid medium was established. The relationship of the reduced absorbency to the concentration of formaldehyde was good linearity and the maximum absorption peak located at 508 nm. The affecting factors on the strength of absorption including temperature, acidity, dosage, coexisting ions and so on, and the optimal conditions of the reaction in the system were investigated. Calibration graphs were linear for ranges of 0 to 1.0 mg/L and a detection limit of 1.1×10-8 g/mL formaldehyde was achieved. The proposed method was successfully applied to the analyses of paint and indoor air samples, with relative standard deviation of less than 1.8% and the recoveries are 94.6％ to 106.2％for the determination of formaldehyde.

Abstract: Single-drop microextraction (SDME) coupled to capillary gas chromatography (GC) was established for the determination of four phthalate esters in wastewater, including dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-octyl phthalate (DnOP) and butyl benzyl phthalate (BBP). The SDME parameters such as extractants, extracting time，stirring rate and immerging depth of needle point were studyed and optimized. The abovementioned phthalate esters were quantified by external standardization method using GC coupled with a flame ionization detector (FID). The linear regression calibration curves, detection limits (S/N=3) and the linear ranges of the method for determining each phthalate were determined, respectively. The concentrations of components abovementioned in a real wastewater sample, the average of the recoveries obtained in the spiked wastewater samples and the corresponding relative standard deviations were determined, respectively. The results showed the proposed method several attributes, friendly enviroment, economic and highly efficient pretreatment, less time, simplicity, sensitivity, accuracy and wide linear range and so on.

Abstract: Single-drop microextraction (SDME) coupled to capillary gas chromatography (GC) was established for the determination of seven volatile halogenated hydrocarbons in wastewater, including chloroform (CF), carbon tetrachloride (CT), trichloroethylene (TCE), bromodichloromethane (BDCM), perchlorethylene (PCE), dibromochloromethane (DBCM) and bromoform (BF). The SDME parameters such as extractants, extracting time，stirring rate and immerging depth of needle point were studyed and optimized. The abovementioned halogenated hydrocarbons were quantified by external standardization method using GC coupled with a flame ionization detector (FID). The linear regression calibration curves, detection limits (S/N=3) and the linear ranges of the method for determining each halogenated hydrocarbons were determined, respectively. The concentrations of componds abovementioned in a real wastewater sample, the average of the recoveries obtained in the spiked wastewater samples and the corresponding relative standard deviations were determined, respectively. The results showed the proposed method several attributes, friendly enviroment, economic and highly efficient pretreatment, less time, simplicity, sensitivity, accuracy and wide linear range and so on.

Abstract: This study focused on the effect of chlorine on disinfection by-product (DBPs) formation. The concentration of DBPs and total residual chlorine were measured at the same time in synthetic drinking water. Chlorine demand and DBPs increased with chlorine dose and contact time. The descending DBPs formation potential rank was: TCM > DCAA > TCAA > TCNM > BDCM. Furthermore, a linear relation between the concentrations of DBPs (HAAs, THMs or TNMs) and chlorine demand was discovered, and the coefficients did not correlate with chlorine dose. Emerging N-DBPs such as HANs did not follow those disciplines because of their special structures. These results have instructive meanings to the further control of DBPs.

Abstract: When Puguang gas field in non-normal production of hydrogen sulfide emissions from the combustion generates sulfur dioxide, in order to prevent its impact on the environment, the need for its emergency absorption. Used static weight-loss method study of A3 steel, 304 stainless steel, aluminum, H62 copper in 10% of (NH4)2SO3 solution, 10% of NH4HSO3 solution, and the mixed solution of 10% (NH4)2SO3 and NH4HSO3 respectively, optimized absorption system of material, and using the electrochemical impedance spectroscopy and anodic polarization curve analysis of several kinds of material in the absorption product solution of the corrosion condition. The results showed that 304 stainless steel corrosion resistance of the best, in 10% of (NH4)2SO3 solution, 10% of NH4HSO3 solution, and the mixed solution of 10% (NH4)2SO3 and NH4HSO3 respectively.

Abstract: Nano-size ZnO of one dimensional structure was prepared by solvothermal synthesis through dissolution-crystallization mechanism and characterized by TEM and XRD. Moreover, photocatalytic degradation rate of dye Rhodamine B (RhB) at the present of nano-size ZnO were carried out, and the results indicated that the nano-size ZnO prepared by such a method has excellent photocatalytic properties.