Ionic liquids and deep eutectic solvents for application in pharmaceutics

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Earthquakes and robustness for timber structures

Major similarities between robustness assessment and seismic design exist, and significant information can be brought from seismic design to robustness design. As will be discussed, although some methods and limitations considered in seismic design can improve robustness, the capacity of the structure to sustain limited damage without disproportionate effects is significantly more complex. In fact, seismic design can either improve or reduce the resistance of structures to unforeseeable events, depending on structural type, triggering event, structural material, among others.European Cooperation in Science and Technology (COST

Earthquakes and robustness

This guideline was prepared within the COST Action E55 "Modelling of the performance of timber structures" WG3 "Robustness of Structures". The main objective of the Action is to provide the basic framework and knowledge required for the efficient ans sustainable use of timber as a structural and building material. Focus is directed on the aspects of design, construction, assessment and maintenance of competitive and high performance timber structures. The Action mainly considers high performance structures where the load-bearing capacity is of predominant interest; for example, structures such as timber bridges, large-span halls and roofs, and also load-bearing elements of other types of timber structures

Organic salts based on isoniazid drug: Synthesis, bioavailability and cytotoxicity studies

UIDB/50006/2020 POCI-01-0145-FEDER?007265 PTDC/QUI-QOR/32406/2017 MAR-02.01.01-FEAMP-0042Tuberculosis is one of the ten causes of morbidity and mortality worldwide caused by Mycobacterium tuberculosis complex. Some of the anti-tuberculosis drugs used in clinic studies, despite being effective for the treatment of tuberculosis, present serious adverse effects as well as poor bioavailability, stability, and drug-resistance problems. Thus, it is important to develop approaches that could provide shorter drug regimens, preventing drug resistance, toxicity of the antibiotics, and improve their bioavailability. Herein, we reported the use of organic salts based on the isoniazid drug, which can act as an organic cation combined with suitable organic anions such as alkylsulfonate-based (mesylate, R or S-Camphorsulfonate), carboxylate-based (glycolate, vanylate) and sacharinate. The synthesis, characterization, and cytotoxicity studies comparing with the original isoniazid drug have been performed. The possibility to explore dicationic salts seems promising in order to improve original bioavailability, and promote the elimination of polymorphic forms as well as higher stability, which are relevant characteristics that the pharmaceutical industry pursues.publishersversionpublishe

Chiral ionic liquids based on L-cysteine derivatives for asymmetric aldol reaction

POCI-01-0145-FEDER–007265 PTDC/QUI-QOR/32406/2017 022161Structure, and consequently properties, of ionic liquids can be easily tailored by changing cation/anion combinations and/or attaching functional groups. By grafting enantiopure moieties to the framework of ionic liquid it is possible to prepare bioinspired chiral molecules that can serve as a reaction medium, additive or even asymmetric catalyst. In this context, new chiral ionic liquids (CILs), based on biomolecules, such as aminoacids (L-cysteine derivatives), have been synthesised and tested in asymmetric aldol condensation of aldehydes and ketones. The best results were obtained for CILs composed of S-methyl-L-cysteine cation and bis(trifluoromethane)sulfonimide anion, in the reaction of 2-or 4-nitrobenzaldehyde with acetone or cyclohexanone, giving the aldol product in moderate yields 70–76% and high ee values (up to 96%).publishersversionpublishe

Robustness analysis of traditional timber trusses

In the present work, the safety of existing traditional timber trusses is evaluated, with particular emphasis on the structural robustness. Traditional Portuguese timber trusses are analyzed probabilistically, using the information provided in the JCSS model code, combined with action and resistance models provided in the Eurocodes. Robustness is evaluated through introduction of a localized defect, simulating deterioration, construction error or damages. The comparison between the reliability index considering a defect and the corresponding index for an intact structure is defined as a measure of susceptibility to local damage. The reliability index is computed using Monte-Carlo simulation combined with linear elastic finite elements for different examples.Cost Action E55 “Modelling of timber performance”

Inference on stiffness and strength of existing chestnut timber elements using Hierarchical Bayesian Probability Networks

The assessment of the mechanical properties of existing timber elements could benefit from the use of probabilistic information gathered at different scales. In this work, Bayesian Probabilistic Networks are used to hierarchically model the results of a multiscale experimental campaign, using different sources of information (visual and mechanical grading) and different sample size scales to infer on the strength and modulus of elasticity in bending of structural timber elements. Bayesian networks are proposed for different properties and calibrated using a large set of experimental tests carried out on old chestnut (Castanea sativa Mill.) timber elements, recovered from an early 20th century building. The obtained results show the significant impact of visual grading and stiffness evaluation at different scales on the prediction of timber members’ properties. These results are used in the reliability analysis of a simple timber structure, clearly showing the advantages of a systematic approach that involves the combination of different sources of information on the safety assessment of existing timber structures

New Protic Ionic Liquids as Potential Additives to Lubricate Si-Based MEMS/NEMS

Funding Information: The work was financed by the Portuguese Foundation for Science and Technology (FCT) through the projects UIDB/00100/2020, UIDP/00100/2020 and IMS-LA/P/0056/2020 and through the PhD grant SFRH/BD/140079/2018 from Mariana Donato. Additionally, this work was financed by national funds from FCT in the scope of the projects UIDB/50022/2020 (IDMEC/LAETA) and LA/P/0037/2020, UIDP/50025/2020 and UIDB/50025/2020 of the Associate Laboratory Institute of Nanostructures, Nanomodelling and Nanofabrication—i3N. Publisher Copyright: © 2023 by the authors.The motivation for this work was to develop new protic ionic liquids (PILs) as additives for the lubrication of micro and nanoelectromechanical systems (MEMS and NEMS). Ten PILs based on the combination of methylimidazolium ([MIMH]), 4-picolinium ([4-picH]), pyridinium ([PyrH]), 1,8-diazabicyclo[5.4.0]-undec-7-ene-8-ium ([DBUH]) and tetramethylguanidinium ([TMGH]) cations with hydrogen sulfate([HSO4]) and mesylate ([MeSO3]) anions were tested as additives in polyethylene glycol (PEG200) to lubricate steel/silicon and silicon/silicon contacts. The best additive was [4-picH][HSO4], which adsorbed strongly on the Si surface, leading to a protective film that reduced wear by up to 15 times compared to PEG200.publishersversionpublishe

Bio-inspired Systems for Carbon Dioxide Capture, Sequestration and Utilization

This chapter reviews the study and development of biological, enzymatic and bio-molecular systems for carbon dioxide capture and further sequestration or even utilization. Regardless of the interest on the use of the captured CO2 as C1 synthon on the manufacture of added-value compounds, there is a tremendous unbalance between the requirements of the contemporary society (leading to a massive production of carbon dioxide) and the framework of commercialization of the products from CO2 utilization. In this context, viable options are storage as a solid in the form of calcium or magnesium carbonate and conversion into other energetic frameworks. In addition, it is important to highlight that the conventional energy resources are progressively being replaced by renewable resources. While the change in energetic paradigm is not accomplished, systems that capture and convert carbon dioxide are highly sought. To this end, bio-inspired systems will be presented, starting from the use of compounds from the chiral pool, such as amino acids, saccharides and related bio-polymers, involved in the physical and chemical capture, sequestration and/or utilization of CO2. Additionally, enzymatic systems are presented in the context of sequestration of CO2 in the form of solid carbonates or even utilization of this C1 synthon in the preparation of fuels and commodity chemicals. Carbonic anhydrase is by far the most studied enzyme, as it catalyses the inter-conversion between CO2 and hydrogencarbonate in an effective mode. The biological option comprises the utilization of methanogens, acetogens and other organisms leading to the formation of added-value compounds. Most of the described systems are based on microbial electro-synthesis model and microbial carbon-capture cell prototypes