Publications by authors named "Maria Neftali Rojas Valencia"

The validation of a feasible application for the production of sustainable bricks with local materials in humid and hot climates, which would allow the current housing needs of a constantly growing population with scarce economic resources to be met while also reducing energy inputs for climate control, is a current challenge without a definitive solution. Therefore, this research studied the incorporation of local aggregates and two second-generation materials to produce lime-stabilized Compressed Earth Blocks (CSEBs) using a semi-automatic machine for their manufacture. An initial matrix was designed as a baseline, and three more were developed with variations to incorporate second-generation materials individually and as mixtures.

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The building industry generates millions of tons of construction and demolition waste annually (12 million tons/year are generated in Mexico, of which only 4% is reused or recycled). Concomitantly, the demand for goods and services by the building industry causes significant environmental impacts. On the other hand, plastic waste is also difficult to assimilate into the environment in the short term, and its recovery is of special interest.

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The main aim of this research was to compare a bio-coagulant, organic coagulant, and a conventional coagulant applied to the treatment of leachates. Coagulant options were Stage 1 FeCl, Stage 2 Polyamine, and Stage 3 mucilage (OFM). Optimal conditions for maximum chemical oxygen demand (COD) removal were determined by experimental data and Response Surface Methodology.

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The objective of this paper is to offer an approach to assess the risk associated with Municipal Solid Wastes, in a geospatial context. Initially, a risk index including hazard, vulnerability and other important variables was built. The built model is based on multi-criteria evaluation techniques and geographic information systems.

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The construction sector generates 14,000 t/d of construction waste in Mexico City, these materials do not have real applications and end up accumulating in landfills. This work, the objective of which was to analyze the physicochemical and mineralogical properties of soil and construction waste used in the manufacture of Recoblocks, is divided in five stages. First, the excavation material was submitted to field tests.

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Evidence of the negative effects of several pharmaceutical molecules, such as hormones and steroids, on the environment can be observed throughout the world. This paper presents the results of the anodic oxidation of the mixture of gestodene steroid hormones and 17 α-ethinylestradiol present in aqueous medium. The tests were conducted in an undivided cell containing a working volume of 50 mL, using a NaSO solution as support electrolyte and boron-doped diamond electrodes.

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This study relates to a method for evaluating the degradation efficiency of Ascaris lumbricoides eggs through a Fenton reaction, using hydrogen peroxide (H2O2) at 100, 250, and 500 mg/L, ferrous sulfate (FeSO4) at 458 mg/L Fe(2+) and pH values of 3, 4.5, and 6. The experiments were conducted according to a 3(2) experimental design, with 1:1, 3:1, and 5:1 (H2O2/Fe(2+)) molar ratios.

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