Advanced Materials Research Vols. 884-885

Abstract: This paper describes experimental work on laser-controlled combustion of solid propellants. Combustion of AP/HTPB, including ignition, combustion, extinction and re-ignition could be controlled by CO₂ laser irradiation at the back pressure of 0.1, 0.3 and 0.5 MPa in nitrogen. Burning rate of propellant increased linearly with the increasing of laser power density. Vieilles law was used here to check pressure effect to burning rate, pressure exponent under different power density (except 0.5 MW/m²) are very close to 0.17.

Abstract: The objectives of this study were to investigate impact of preoxidation on disinfection by-product (DBP) precursors in drinking water via two different preoxidation methods. The full-scale study was conducted on surface river water in a water supply plant in Tianjin, China. Two treatment trains were performed, with prechlorination and preozonation as preoxidation methods, respectively. The water samples were collected on different stages along the treatment processes and analyzed by following organic parameters: dissolved organic carbon (DOC), UV₂₅₄ and specific ultraviolet absorbance (SUVA). The results indicated that Train 2 with preozonation was more effective to reduce DBP precursors. Preozonation possessed an excellent ability in the removal of UV₂₅₄ and SUVA, the removal efficiencies were 25.14% and 18.77%, respectively, comparing to the removal rates of 6.66% and 5.64% during prechlorination, separately.

Abstract: Many gas-condensate reservoirs experience a sharp drop in gas production owing to condensation near the wellbore as pressure drops lower than the dew point. It has been a challenge for a long time to develop cheaper chemical to stop the dramatic decline in gas production. In this study several molecule formulas are designed, properties of two chemicals for wettability alteration are predicted using molecular modeling method and then synthesized. Analysis result shows high conformity between the prediction and experimental properties.

Abstract: Many attentions have been paid on wettability alteration to gas wetness since it is widely concerned in 2000. Although many researchers tried to explain or realize such phenomenon, several problems have not been resolved now including possibility and mechanism of wettability alteration in water saturated cores. In this study, new insight is made into wettability alteration to gas wetness, both experimental and simulate. A serial of spontaneous water imbibition experiments are conducted to evaluate applicability of wattability alteration in different water saturated cores. SEM observation indicates microcosmic mechanism by compare of pore surface before and after chemical treatment. Numerical simulation in Eclipse gives theoretical evidence of wettability alteration phenomenon and also proves almost the same result with that in spontaneous water imbibition experiments.

Abstract: For the water-sweeping gas reservoir, especially when the water-body is active, water invasion can play positive roles in maintaining formation pressure and keeping the gas well production. But when the water-cone break through and towards the well bottom, suffers from the influencing of gas-water two phase flows, permeability of gas phase decrease sharply and will have a serious impact on the production performance of the gas well. Moreover, the time when the water-cone breakthrough will directly affect the final recovery of the gas wells, therefore, the numerical simulation method is used to conduct the research on the key influencing factors of water-invasion performance for the gas wells with bottom-water, which is the basis of the mechanical model for the typical gas wells with bottom-water. It indicate that as followings: (1) the key influencing factors of water-invasion performance for the gas wells with bottom-water are those, such as the open degree of the gas beds, well gas production and the amount of Kv/Kh value; and (2) the barrier will be in charge of great significance on the water-controlling for the bottom water gas wells, and its radius is the key factor to affect water-invasion performance for the bottom water gas wells where the barriers exist nearby.

Abstract: This paper is mainly aimed at the problem of low bonding strength of soy bean protein adhesive,poor water resistance,with methyl methacrylate and vinyl acetate composite study made with rubber manufacturing class II plywood,meet the national standard,so as to solve the water resistance of soy protein adhesives and bonding strength of.Experiments that 3.5g soy protein, 5g PVA, 30g MMA, 0.3g APS and 100g water, modified soy protein adhesive bonding strength obtained is excellent, and cost reduction.Preparation of soybean protein-acrylate adhesive solid content,viscosity and strength of plywood detection.

Abstract: Anti-fouling PLA hollow fibers were fabricated using synthesized PLA-PEG-PLA copolymer as an additive to improve the hydrophilicity. The tri-block copolymer was prepared by ring-opening polymerization and a hydrophilic copolymer processing good compatibility with PLA molecule was obtained and utilized to fabricate membrane with PLA by NIPS. Elemental analysis showed that PLA-PEG-PLA could stably exist in membranes and endow the membrane with persistent hydrophilic. Thus the contact angle decreased nearly 20^o with 5% PLA-PEG-PLA content, resulting in higher water permeability and BSA rejection which indicated the anti-fouling property of PLA membrane was improved.

Abstract: The catalyst Fe/SiO₂ was prepared by impregnation method and used as catalyst for treating the dye wastewater by catalytic wet peroxide oxidation method. The catalyst preparation process was optimized, and under the conditions of: the particle size of catalyst carrier was 0.125-0.200 mm, concentration of iron nitrate was 1.10mol/L, calcination temperature was 600 °C, and calcination time was 4h, the catalyst has higher activity and better stability in treating the wastewater.

Abstract: Two magnetites (M-20 and M-80) were successfully prepared by two different methods. The XRD patterns showed that M-20 was a poorly crystalline magnetite and M-80 possessed a relatively well crystallinity. For M-20 and M-80, the specific surface area (SSA) was 48.53 and 26.72 m²/g; at pH 5.0 the zeta potential was 28.34 and 23.51 mV; and the isoelectric point (IEP) was 6.8 and 7.0, respectively. At pH 5.0, the Langmuir adsorption capacity for fluoride of M-20 and M-80 was 12.45 and 9.89 mg/g, respectively. This indicates that M-20 is a higher efficient adsorbent for fluoride removal from waters compared to M-80. Langmuir model was suitable to fit the fluoride adsorption data of M-20 and M-80 (R² =0.988 and 0.982, respectively) and Freundlich model can not well fit the fluoride adsorption data of the two magnetites (R² =0.937 and 0.951, respectively).

Abstract: Removal of manganese (II) ions from wastewater by H₂O₂ as oxidant was studied. Effects of reaction temperature, hydrogen peroxide concentration, reaction time and calcium oxide concen-tration on the manganese removal were investigated. The results indicated that the removal rate of manganese exceeded 99.9% and the Mn (II) ions concentration of treated wastewater was lower than 0.1 mg·L^-1 under the conditions of reaction temperature 55 °C, concentration of H₂O₂ 0.1 mL·L^-1, reaction time 70 min, concentration of CaO 0.25 g·L^-1.