Comparison of Conventional and Ultrasound-assisted Extraction Techniques on Mass Fraction of Phenolic Compounds from Sage (Salvia officinalis L.)

An innovative ultrasound-assisted extraction (UAE) is the rapid non-thermal extraction technique, which in comparison to conventional extraction (CE), offers high reproducibility in a short time with simplified manipulation, reduced solvent consumption and lower energy. Optimization of ultrasonic conditions was conducted for devices with nominal output power of 100 and 400 W, including the influence of geometrical parameters of probes regarding ultrasound-assisted extraction. The results showed that the optimal parameters for extraction of total phenols and rosmarinic acid as a dominant compound in sage extracts were as follows: solvent: 30 % ethanol, extraction duration of 11 minutes, and ultrasonic device output power of 400 W. The antioxidant capacity of the obtained extract correlated with the concentration of total phenols and flavonoids, and among individual phenols the rosmarinic acid contributed the most to the antioxidant capacity. The achieved results and statistical analysis (p ≤ 0.05) have shown how UAE resulted in shorter extraction time, and increased extraction capacity of phenolic compounds by using solvents with a less amount of organic phase

Performance based studies of in-plane loaded unreinforced masonry walls

The shear capacity of masonry subjected to both monotonic and cyclic loading was experimentally studied in order to assess its potential seismic performance. The strength and deformation characteristics of both the masonry assembly and its components were studied. The performance of the masonry panels subjected to pre-compression and in-plane load was assessed both in relation to failure criteria postulated by previous investigations as well as the Euro Code (EC) provisions. The results were also assessed in terms of Performance Based Design (PBD). The results show that, by considering the results of testing the brick-mortar interface and of compressive and diagonal tests of masonry specimens, the performance of in-plane laterally loaded masonry walls under cyclic loading can be well predicted for brickwork made from stiffer mortars. The proposed model for evaluating the characteristic shear strength from EC6 using the partial safety factors according to the provisions of EC8 can accurately predict the design shear strength of the masonry derived from cyclic shear tests under different levels of pre-compression. However, for diagonally loaded walls under monotonic loading, the partial safety factors given by EC6 seem to be too severe. For wall specimens under cyclic loading, using the results from the splitting tensile tests of the masonry in conjunction with Turnsek's model gave a better prediction of the design shear strength

Progress on testing of mechanical properties of cement-based materials - Extended Round Robin Test of COST Action TU1404

The Extended Round Robin Testing program (RRT+) of COST ACTION TU1404 is the main activity within Working Group 1 (WG 1): Testing of cement-based materials (CBMs). In its main phase that is currently under way, the RRT+ program is divided into six group priorities, among which group priority 1d (GP1d) deals with mechanical properties and creep of CBMs across several scales – hardened cement paste, mortar and concrete. One of the aims of the RRT+ as a whole is to extensively characterize a set of predefined CBM’s and support the development and validation of material models in WG2 - modelling and benchmarking. After six months of development of the Main Phase of RRT+ , results of 13 laboratories are available for analyses in the scope of GP1d. In this paper we focus on the correlation between compressive strength of concrete and corresponding mortar and hardened cement paste, and on the reproducibility of unloading modulus of elasticity of concrete in compression. Among advanced testing methods of GP1d we present the results of EMM-ARM method, which enables continuous measurement of elasticity modulus of CBMs after casting.The authors would like to acknowledge networking and dissemination support by the COST Action TU1404 (http://www.tu1404.eu/). The research performed within the RRT+ program of the COST Action is on volunteering basis, since there is no budget foreseen for research activities. Therefore, the authors would like to express their sincere gratitude to all participating laboratories for their dedicated work within this experimental campaign. The authors also acknowledge financial support of EDF, France, CEVA Logistics, Austria and Germany, OeBB Infra, Austria, Staten Vegvesen, Norway and Schleibinger Gerate, Germany. This work was partially supported by: project POCI-01-0145-FEDER-007633 (ISISE), funded by FEDER funds through COMPETE2020 - Programa Operacional Competitividade e Internacionalização (POCI), and by Portuguese funds through FCT - Fundação para a Ciência e a Tecnologia. FCT and FEDER (COMPETE2020) are also acknowledged for their funding of the research project IntegraCrete PTDC/ECM-EST/1056/2014 (POCI-01-0145-FEDER016841).info:eu-repo/semantics/publishedVersio

Sensitivity analysis for setting up the investigation protocol and defining proper confidence factors for masonry buildings

At present, the codified procedures for the seismic assessment of existing structures do not consider explicitly the use of sensitivity analysis that, on the contrary, is an essential tool due to the intrinsic and epistemic un-certainties involved. In particular, results of a sensitivity analysis allow, on one hand, to optimize the plan of investigations and tests, limiting it to what is really useful, and, on the other hand, to be aware of the propaga-tion of uncertainties in the final outcome of the assessment. The paper proposes how to implement the sensi-tivity analysis in a systemic way, in order to define proper confidence factors, which are used within the semi-probabilistic approach of the performance-based assessment procedure. In relation to the procedures adopted by current standards, this method is aimed to overcome the following drawbacks: i) the a priori definition of values for the confidence factor; ii) the a priori selection of parameters to which confidence factor has to be applied; iii) the weak connection between investigation and assessment. Despite the generality of most as-pects of the proposed procedure, main attention is given in the paper to its application in the case of masonry existing buildings and, in particular, of those with a significant cultural value, where the minimization of in-vasiveness of investigations on the construction together with that of costs plays a crucial role for the aim of conservation

THE INFLUENCE OF CEMENT REPLACEMENT MATERIALS ON THE FLEXURAL BOND STRENGTH OF MASONRY

Abstract This paper reports on an experimental study of the influence on bond strength of partial Portland cement replacement in mortar. The replacement materials used were either ground granulated blast furnace slag (GGBS) or fly ash (FA). Two mortar types were used, 1:1:6 (cement:lime:sand by volume) and 1:0:5 (with a methyl cellulose additive), in conjunction with high and low suction fired clay units. Bond strengths of masonry joints were obtained at 7 and 28 days using the bond wrench. In all cases, reduced bond strengths were obtained for varying proportions of GGBS and FA replacement. However, the strengths obtained for all blend proportions were still greater than the default bond strength values assumed in the Australian Masonry Code. Detailed results are presented and the causes of strength variations discussed

Structural Integrity of Buildings under Exceptional Fire.

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