【摘 要】
:
We analyzed the influence of sodium polyphosphate (STPP) on the performances of recycled gypsum (RG). This analysis was performed with two different ways of STPP addition: One was that the STPP was added into Plaster of Paris (POP), then recycled plaster
【机 构】
:
College of Material Science and Engineering, Chongqing University, Chongqing 400045, China;Chong Qin
【出 处】
:
武汉理工大学学报(材料科学版)(英文版)
论文部分内容阅读
We analyzed the influence of sodium polyphosphate (STPP) on the performances of recycled gypsum (RG). This analysis was performed with two different ways of STPP addition: One was that the STPP was added into Plaster of Paris (POP), then recycled plaster (R-SP) was obtained after a series of processes and the other was that the STPP was directly put into recycled plaster (R-PS). The conclusions confirmed that STPP increased the water demand and delayed the hydration of R-PS. With regard to its hardened performance, STPP provided hardened recycled gypsum with a loose structure which led to the lower strength and higher water absorption than recycled plaster (R-P) without STPP. On the contrary, the water requirement and the setting time were decreased and shortened by STPP in R-SP, respectively. A dense structure was also possessed by R-SP which contributed to the high strength and low water absorption. The analysis shows that STPP is selectively chemisorbed on the (111) face of R-PS crystals, it inhibits the growth in c axis direction, resulting in the extending of setting time and the transformation of morphology, making the hardened R-PS crystals coarsened, which results in high W/P and low strength. Whereas the low W/P is made by both the rod-like crystals of low length-radius possessed by R-SP and the relatively high ζ-potential absolute value caused by – (PO3Ca) on the surface of R-SP, leading to the complete development of crystals and their close overlapping, thus bringing about the increase of strength.
其他文献
In order to look for the best proportion ofβ-tricalcium phosphate(β-TCP) and poly(lactide-co-glycolide) (PLGA) we fabricated porous compositesβ-TCP/PLGA scaffold using freeze-drying method. Morphological characterization using scanning electron microscopy
Ba0.65Sr0.35TiO3 (BST) nanocrystals doped with different concentrations of Er3+ ion were fabricated using sol-gel method. The structure and morphology of these BST nanocrystals were studied using X-ray diffraction (XRD), field emission scanning electron m
The feasibility of using coral reef sand (CRS) in Portland cement concrete is investigated by testing the mechanical property and microstructure of concrete. The composition, structure and properties of the CRS are analyzed. Mechanical properties and micr
Ti6Al4V substrates were anodized in a 0.5 mol/L H2SO4 solution at applied voltages of 90-140 V. A hydroxyapatite-titanium oxide (HA-TiO2) coating was then deposited on the anodized Ti6Al4V substrates via a hydrothermal-electrochemical method at a constant
Fe3O4-octadecyltrichlorosilane (Fe3O4-OTS) was synthesized and used to remove dyes in a competitive system. Fe3O4-OTS was prepared by slow hydrolysis of OTS in cyclohexane on the surface of Fe3O4 obtained through coprecipitation method. Scanning electron
We developed poly lactic-co-glycolic acid (PLGA) microspheres loaded with cefquinome and tested their effectiveness in a mouse model.The microspheres were prepared by optimizing several key parameters such as PLGA molecular weight,drug/polymer ratio,inter