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The electrochemical oxidation of para-, meta-and ortho-aminophenols was carried out using a platinum electrode in aqueous acid medium. The spectroscopic results indicate that p-aminophenol suffers hydrolysis giving the formation of hydroquinone/pbenzoquinone. CO 2 has been detected by in situ FTIR spectroscopy as the main soluble oxidation product. The m-aminophenol oxidation produces a blocking polymeric film on the platinum surface. The main oxidation products detected by in situ infrared spectroscopy were CO 2 and quinone. Cyclic voltammetry and in situ FTIR spectroscopy were combined to study the redox processes of the conducting polymer obtained in the o-aminophenol oxidation. The spectroscopic results indicate that phenoxazine units are produced during the oxidation/reduction of poly(o-aminophenol).

In this research, strain-sensing and damage-sensing functional properties of cement composites have been studied on a conventional reinforced concrete (RC) beam. Carbon nanofiber (CNFCC) and fiber (CFCC) cement composites were used as sensors on a 4 m long RC beam. Different casting conditions (in situ or attached), service location (under tension or compression) and electrical contacts (embedded or superficial) were compared. Both CNFCC and CFCC were suitable as strain sensors in reversible (elastic) sensing condition testing. CNFCC showed higher sensitivities (gage factor up to 191.8), while CFCC only reached gage factors values of 178.9 (tension) or 49.5 (compression). Furthermore, damage-sensing tests were run, increasing the applied load progressively up to the RC beam failure. In these conditions, CNFCC sensors were also strain sensitive, but no damage sensing mechanism was detected for the strain levels achieved during the tests. Hence, these cement composites could act as strain sensors, even for severe damaged structures near to their collapse.

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Please cite this article as: Baeza-Brotons F, Garcés P, Payá J, Saval JM, Portland cement systems with addition of sewage sludge ash. Application in concretes for the manufacture of blocks, Journal of Cleaner Production (2014), doi: 10.1016/j.jclepro.2014.06.072. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT Highlights 1. Sewage sludge ashes (SSA) were used for preparing dry consistency concrete 2. SSA-concrete blocks were fabricated and fully characterized 3. Addition of SSA (up to 20% of weight of cement) was successfully achieved 4. In blocks containing SSA, good water absorption behavior was achieved 5. A new valorization way for SSA could be implemented in the construction industry M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT 16This study analyzes the viability of using sewage sludge ash (SSA) as a raw material in the 17 composition of concrete, with a similar dosage to when it is used to manufacture blocks, therefore, 18with dry consistency given the type of the industrial process of these precast. These ashes are a serious