The OECD NEA (Nuclear Energy Agency) anticipates that by 2050 the amount of nuclear-generated electricity worldwide will increase by a minimum of 1.6 times and a maximum of 3.9 times its 2008 value of 372 GWe [1]. At the same time, the amount of radioactive waste that will be produced is expected to increase substantially. High-level radioactive waste is usually derived from the burning of uran...

Cementitious waste forms (CWFs) are an important component of the strategy to stabilize nuclear waste resulting from plutonium production by the U. S. Department of Energy. Technetium (99Tc) is an abundant fission product of particular concern in CWFs because of the high solubility and mobility of Tc(VII), pertechnetate (TcO4-), the stable form of technetium in aerobic environments. CWFs can mo...

Ahstract--Mn-substituted iron oxides were synthesized by coprecipitating Fe(NO3)3 and Mn(SO4) solutions with NH4OH, adjusting the suspensions to pH 4 or 6, and then keeping the suspensions at 55~ for 62 days. The Mn mole fraction of the final products ranged from 0 to 0.3. X-ray powder diffraction patterns showed that goethite and hematite formed in each Fe-containing system. Groutite formed in...

Semi-Flexible Pavement (SFP) is a composite type of pavement produced by manufacturing porous asphalt mixes using open graded aggregate gradation to create 20-35% voids filled with grout (cement paste, cement mortar, etc.….). The resulting has the flexibility and some strength concrete pavement. current study focused on investigation widely available (in Iraq) waste material namely Rice Husk As...

Consider a mosaic image, the edges of the tesseræ being unrelated to pictorial content. Depending upon grout color, the picture is seen as uninterrupted "behind bars" or divided into tiles by "cracks" as in an ancient oil painting. The phenomenology is explored.

Grout sleeve splicing of rebar is a major technology in prefabricated buildings, and cementitious grout for (hereinafter called grout) an essential material this technology. Grout, with its excellent mechanical properties, improves the stability splicing. In study, properties were improved by introducing admixture form defoamer, influence defoamer on fluidity, loss rate wet apparent density str...

INTRODUCTION Beijing subway line 14 includes four stations and approximately 2.8 km of tunnels between the Dongfengbeiqiao and Jingshunlu areas of the city. Due to the surface and underground space limitations of this section, a double-track running tunnel instead of two single-track running tunnels was adopted to connect the two stations. The double-track tunnels were excavated by a 10.22 m di...