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One of the most important aspect of selecting the proper natural pozzolanic material as admixture of Portland cement in concrete or mortars is the chemical reactivity and mineralogical content. If the chemical reactivity index and quartz content are high the pozzolans can substitute the cement from the binder groundmass in a greater proportion. The paper present mineralogical, petrographical, chemical and mechanical properties of few natural pozzolans (tuffs and perlite) in order to determine if they are proper for usage in cement industry manufacturing. [ABSTRACT FROM AUTHOR]

Abstract: Zeolitic volcanic tuffs are important local reserve, which can be exploited in building materials industry both as rocks and the preparation of mortar for masonry, lightweight concrete or autoclaved aerated concrete. This study presents the results of the tests performed on different mortar recipes that are based on zeolitic volcanic tuff (from Macicaş quarry situated in the north-western part of Cluj-Napoca area) used as a substitute for cement or aggregate. The aim of the study is to obtain new building materialmade from local resources that can be used to realize new masonry works and to rehabilitate the old ones. [Copyright &y& Elsevier]

Abstract: Sustainable building materials are of top quality from technical point of view, with a long lifetime and a low cost of maintenance and exploitation. To ensure the sustainability of a building one of the essential condition is to use local materials with reduced embodied energy, low cost and good appearance. In case of new buildings masonry works can be durable and sustainable in the same time if all the materials (units and mortars) used to realise them have the similar characteristics (mineralogical composition, texture, structure, physical and mechanical properties). The study was performed considering tuffs as masonry units, mortar based on these tuffs (both in substitution of cement and sand), and classical mortar as joining together in order to realise a homogeneous structure. [Copyright &y& Elsevier]

Abstract: The potential of incorporating fodder tree foliage in the production of multinutritional feed blocks (MNBs) to supplement grazing sheep was evaluated. Leaves from Guazuma ulmifolia Lam., Leucaena lanceolata S. Watson, Acacia cochliacantha Humb. & Bonpl. Willd, and Brosimum alicastrum Swartz were used to make 2.5kg blocks which were offered to test the preference, consumption and weight gain in Pelibuey sheep during MNB supplementation while grazing. The MNBs contained 23.5% crude protein, 25% neutral detergent fiber, 17.5% acid detergent fiber, and 63% dry matter in vitro digestibility. Sheep equally preferred MNBs containing B. alicastrum, L. lanceolata, and G. ulmifolia, and less so A. cochliacantha (P>0.05). They also consumed more B. alicastrum MNB dry matter and less from those with A. cochliacantha (P<0.05). Supplementation with MNBs containing B. alicastrum did not increase weight gain (EEM=0.021). However, the nutritional quality of the MNBs might have a higher impact when animal diets in the field are based on low quality forages. [Copyright &y& Elsevier]

Drinking water on isolated islands includes treated rainwater, water shipped from the mainland, and desalinated seawater. However, marine transportation and desalination plants are vulnerable to emergencies, such as extreme weather, making self-sustaining stand-by water for emergency response essential. Rainwater is ideal for producing the stand-by water, and rainwater harvesting is sustainable and clean, and prolonged biostability can be ensured by managing biological and chemical parameters. The present study applied a stand-by drinking water purification system (primarily including nanofiltration and low-dose chlorination) to explore the feasibility of producing and storing cleaner drinking water from rainwater and the following conclusions were drawn. First, treatment of rainwaters ensures biosafety for seven days, which is longer than that for untreated rainwater; the proportion of opportunistic pathogens decreased from 23.40–7.77% after nanofiltration, and it was proposed that the microbial community converges after advanced water treatment. Second, chemical qualities were improved. Local resource coral sand prevents pH in rainwater from decreasing below 6.5, and treated rainwater had lower disinfection by-product potential and higher disinfection efficiency, allowing periodical rainwater recycling. Third, harvesting rainwater was extremely cost-effective, with an operation cost of 1.5–2.5 RMB/m3. From biosafety, chemical safety, and economic cost perspectives, self-sustaining water from rainwater can contributes to the development of sustainable and cost-effective water supply systems on isolated islands. Mixing treated rainwater and desalinated seawater reasonably guarantees sufficiency and safety. Unlabelled Image • Local resource (rainwater, coral sand and seawater) were used to improve the stability and sustainability. • Nanofiltration and low-dose chlorination ensure rainwater safe for production and storage. • Recycling rainwater is more cost-effective than shipping water and RO water. [ABSTRACT FROM AUTHOR]