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Introduction
Published in Fang Lin Luo, Hong Ye, Renewable Energy Systems, 2013
The Earth is the third planet from the Sun with the mass Me (Me—Earth mass is the unit of mass equal to that of the Earth: 5.9722 × 1024kg), and it is the densest and fifth largest of the eight planets in the solar system It is also the largest of the solar system’s four terrestrial planets. It is sometimes referred to as the World, the Blue Planet, or by its Latin name, Terra.
Experimental thermophysical dependent mechanical analysis of earth bricks with Canarium schweinfurthii and Cocos nucifera bio-aggregates - A case study in Cameroon
Published in Cogent Engineering, 2023
Ganou Koungang B.M., Tchamdjou Mbouendeu J. O., Zhao Z, Tchemou G., Michel F., Messan A., Courard L.
The codification chosen for the samples was CEB_CNCS_x-y with the coefficients x and y representing the mass proportion of cement and CNCS aggregates based on the earth mass, respectively (Table 3). The manufacturing process followed several steps including preparation, mixing (Figure 7), compaction and curing. The tests were carried out after 28 days of curing according to ASTM D1632–07 standard (D1632–07, 2007).
Monte Carlo simulations of radiation shielding by rare-earth/polypropylene composites
Published in Radiation Effects and Defects in Solids, 2023
Tongyan Cui, Shuilian Wang, Anying Zhang, Rui Wang, Zhongjian Ma, Qingxiu Jia
After selecting the type of rare-earth filler, the effects of composite thickness and filler content on gamma-ray shielding were analyzed. The variable composite thicknesses were 0.2, 0.4, 0.6, 0.8 and 1.0 cm for a clear comparison, and different filler contents were defined for each thickness. The best rare-earth mass fraction in the composites was then determined.
Study of the State of Conservation and the Building Materials Used in Defensive Constructions in South-Eastern Spain: The Example of Mula Castle in Murcia
Published in International Journal of Architectural Heritage, 2021
M. L. Gutierrez-Carrillo, Anna Arizzi, I. Bestué Cardiel, E. Sebastián Pardo
Inner rammed-earth mass below the top of the wall (Mu-M2): This sample was taken from the inner rammed-earth mass below the top of the wall. It has a light brown, mud-like appearance and is poorly cohesive, which means that it breaks up quite easily. There is a natural patina on the outer surface due to the build-up of clays. Biodeterioration was detected in this sample, in the form of plant remains such as roots. The matrix is off-white and fissured, but there are also some more reddish (iron-rich) areas and other ochre-coloured areas. The sample has quite a low aggregate content. The aggregates have a sand grain size (0.06–2 mm) and are rounded and sub-angular in shape, as observed under the loop. The aggregates are of metamorphic and sedimentary origin. The sample has high porosity with irregular sub-rounded pores. Lime lumps and ceramic fragments of varying size (0.06–2 mm) can also be identified in the matrix. The matrix is quite severely fissured, with cracks and fractures visible around the aggregates and lime lumps. From the mineralogical study by XRD, calcite and quartz were identified as the main phases and dolomite, feldspars, muscovite, kaolinite and aragonite were also detected in minor amounts (Figure 7). From the petrographic study (Figure 10) we deduced that the matrix of the rammed-earth block is calcitic, which suggests that this building material was made from a mixture of calcitic lime and clays, which also included siliceous and carbonated aggregates with a sand grain size. The sample has a low aggregate content, and some lime lumps can be observed. The siliceous aggregates contain the following mineral phases: quartz (around 17%), phyllosilicates of a kaolinite and muscovite type (according to XRD) and feldspars, while the carbonated aggregates (around 65%) are composed of calcite and dolomite (both altered). Many fossil-rich limestone fragments were observed dispersed in the matrix. The porosity of this sample is medium, and the cohesion between the matrix and the aggregate grains seems to be higher than in the previous samples, although some shrinkage fissures have been observed.