Search results for "Salt"
showing 10 items of 1157 documents
Effects of natural fibres reinforcement in lime plasters (kenaf and sisal vs. Polypropylene)
2014
Nowadays the tendency to realize environment-friendly products is becoming more widespread to ensure sustainable and smart development. The synthetic fibres, frequently used, are harmful to the environment because they are non-degradable and non-renewable. Their use has resulted in an increase of oil consumption. Therefore, the possibility of replacing them with natural fibres becomes increasingly concrete confirmed by the researches and investigations carried out. In this work three lime based plasters were prepared and analysed to evaluate the influence on their performance of different fibres used as reinforcement. In particular each plaster was realised by adding to the mortar the same …
Mesomorphic and electrooptical properties of viologens based on non-symmetric alkyl/polyfluoroalkyl functionalization and on an oxadiazolyl-extended …
2019
Two different sets of ionic liquid crystals based on bistriflimide salts of non-symmetrically substituted polyfluorinated bipyridinium (viologens) and bent symmetrically substituted dialkyl-oxadiazolyl-bipyridinium have been synthesized, in order to study the effect on the mesomorphic and electrooptical properties of the non-symmetric functionalization (alkyl chain and fluoroalkyl chains of different lengths) on the two pyridinium rings and additionally the effect of a bent conjugated spacer among the two pyridinium units of the viologen. POM and DSC characterization show that the synthesized salts have a mesomorphic and, in some cases, polymesomorphic behaviour in a wide thermal range, als…
Eine apparatur zur gaschromatographischen verfolgung der metathesereaktion kurzkettiger olefine
1973
Es wird eine Apparatur beschrieben, die einen Reaktor, kombiniert mit einem Gaschromatographen, umfast und die es gestattet, Umsetzungen kurzkettiger Olefine bei der Metathesereaktion schnell und einfach zu erfassen. Die Leistungsfahigkeit der Apparatur wird u. a. am Beispiel der Metathesereaktion von Penten-2 in Gegenwart des Katalysator-systems WCl6/C2H5OH/(C2H5)3Al2Cl3 demonstriert. An apparatus consisting of a reactor tube in conjunction with a gaschromatograph is described which allows to follow instantaneously the progress of the metathesis reaction of short chain olefins. The ability of the apparatus is demonstrated among other things by means of the metathesis reaction of pentene-2 …
Influence of sodium bicarbonate treatment on the aging resistance of natural fiber reinforced polymer composites under marine environment
2019
Abstract Aim of the current study is to investigate how an innovative and eco-friendly chemical treatment based on sodium bicarbonate solution (10 wt%) can improve the aging resistance in marine environment of epoxy based composites, reinforced with flax and jute fibers. To this scope, treated and untreated fiber reinforced composites were manufactured through vacuum infusion technique. The resulting composites were then exposed to salt-fog spray conditions up to 60 days, according to ASTM B117 standard. The assessment of their durability was made by means of tensile, flexural quasi-static tests and Charpy impact tests. Furthermore, the water uptake evolution of each composite was monitored…
Pinned hybrid glass-flax composite laminates aged in salt-fog environment: Mechanical durability
2019
The aim of the present paper is to study the mechanical performance evolution of pinned hybrid glass-flax composite laminates under environment aging conditions. Hybrid glass-flax fibers/epoxy pinned laminates were exposed to salt-spray fog environmental conditions up to 60 days. With the purpose of assessing the relationship between mechanical performances and failure mechanisms at increasing aging time, single lap joints at varying joint geometry (i.e., hole diameter D and hole distance E from free edge) were characterized after 0 days (i.e., unaged samples), 30 days, and 60 days of salt-fog exposition. Based on this approach, the property&ndash
Effects of anodizing surface treatment on the mechanical strength of aluminum alloy 5083 to fibre reinforced composites adhesive joints
2021
Abstract In this study, the anodizing process based on the use of tartaric sulfuric acid solution (TSA) was carried out on metal substrate to evaluate for the first time its effect on the adhesion strength and corrosion resistance of aluminium alloy (i.e., AA5083) to fibre (i.e., basalt or glass) reinforced composite adhesive joints for nautical applications. Furthermore, some TSA anodized samples were soaked in a NaOH solution to investigate the influence of this post-immersion step on the joint performances. With the aim to improve the fibre-matrix adhesion in the composite substrate thus further increasing the overall mechanical response of the joint, glass and basalt fibres were treated…
Effect of glass fiber hybridization on the durability in salt-fog environment of pinned flax composites
2021
The aim of the present paper is to evaluate the effect of the hybridization with external layers of glass fibers on the durability of flax fiber reinforced composites in severe aging conditions. To this scope, full glass, full flax and hybrid glass–flax pinned laminates were exposed to a salt-fog environment for up to 60 days. Double-lap pinned joint tests were performed to assess the pin-hole joints performances at varying the laminate stacking sequence. In order to better discriminate the relationship between the mechanical behavior and the fracture mechanisms of joints at increasing the aging time, different geometries (i.e., by varying both the hole diameter D and the free edge distance…
Energy Consumption for the Desalination of Salt Water Using Polyelectrolyte Hydrogels as the Separation Agent
2017
The energy consumption for a novel desalination approach using charged hydrogels under externally applied pressure is experimentally measured and calculated. The salt separation is based on a partial rejection of mobile salt ions caused by the fixed charges inside the polyelectrolyte network. Self-synthesized and commercial poly(acrylic acid) hydrogels are used to study the desalination performance in reference to sodium chloride solutions within the concentration range of 0.1–35 g L−1. The influence of various synthetic parameters, such as the degree of crosslinking (DC) and the size and shape of the particles, is investigated. Furthermore, the effect of process parameters including the am…
Insights into the effect of the spacer on the properties of imidazolium based AIE luminogens
2021
Abstract With the aim to obtain organic salts with potential applications in high performance molecular electronics, we combined properties of π-conjugated spacers, like 1,4-diethynylbenzene and 1,6-diethynylpyrene, with the ones of both imidazole and imidazolium units. Physico-chemical properties of obtained fluorescent organic salts were investigated performing thermo-gravimetric analysis (TGA), differential scanning calorimetry (DSC) and cyclic voltammetry measurements (CV). Photophysical behavior of the salts was analyzed in conventional solvents and ionic liquids, by UV–vis and fluorescence investigation. Solution phase aggregation study revealed that these salts self-assemble in conve…
Magnetic Polyurethane Microcarriers from Nanoparticle-Stabilized Emulsions for Thermal Energy Storage
2020
Hydrated inorganic salts are phase change materials (PCMs) with promising thermal energy storage capacity. However, their application is commonly restricted because of problems of phase segregation...