Effect of Electro-kinetic Consolidation on Fine Grained Dredged Sediments

Abstract The management of the huge amount of dredged sediments is an important issue to be solved worldwide, and dewatering is by far the most critical step when fine grained sediments are involved. Different technologies have been proposed in time to speed up the process. Even though electro-kinetic treatment is in principle one of them, it has not been implemented yet at an industrial scale, and only few trial applications are known. For such a reason, a multidisciplinary research activity is ongoing at the University of Napoli Federico II in the framework of the EU commitment ROSE with the aim to analyse the effectiveness and feasibility of such a technology from the lab to the site scale. In this paper, some evidences stemming from lab tests are presented. The results indicate that the application of low voltages improves the mechanical behaviour of the tested soil. In this case, however, the improvement is due more to a change in microstructure than to a decrease in void ratio

The Seneca nation of Indians and the city of Salamanca : an analysis of the Senecas' options for renewal of the 99-year leases of Salamanca

Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 1984.MICROFICHE COPY AVAILABLE IN ARCHIVES AND ROTCH.Includes bibliographical references.by A. Lucia Mele.M.C.P

Green Aspects in Molecularly Imprinted Polymers by Biomass Waste Utilization

Molecular Imprinting Polymer (MIP) technology is a technique to design artificial receptors with a predetermined selectivity and specificity for a given analyte, which can be used as ideal materials in various application fields. In the last decades, MIP technology has gained much attention from the scientific world as summarized in several reviews with this topic. Furthermore, green synthesis in chemistry is nowadays one of the essential aspects to be taken into consideration in the development of novel products. In accordance with this feature, the MIP community more recently devoted considerable research and development efforts on eco-friendly processes. Among other materials, biomass waste, which is a big environmental problem because most of it is discarded, can represent a potential sustainable alternative source in green synthesis, which can be addressed to the production of high-value carbon-based materials with different applications. This review aims to focus and explore in detail the recent progress in the use of biomass waste for imprinted polymers preparation. Specifically, different types of biomass waste in MIP preparation will be exploited: chitosan, cellulose, activated carbon, carbon dots, cyclodextrins, and waste extracts, describing the approaches used in the synthesis of MIPs combined with biomass waste derivatives

Raclopride-Molecularly Imprinted Polymers: A Promising Technology for Selective [11C]Raclopride Purification

In this work, we developed a novel approach to purify [C-11]Raclopride ([C-11]RAC), an important positron emission tomography radiotracer, based on tailored shape-recognition polymers, with the aim to substitute single-pass HPLC purification with an in-flow trap & release process. Molecular imprinting technology (MIT) applied to solid phase extraction (MISPE) was investigated to develop a setting able to selectively extract [C-11]RAC in a mixture containing a high amount of its precursor, (S)-O-Des-Methyl-Raclopride (DM-RAC). Two imprinted polymers selective for unlabeled RAC and DM-RAC were synthesized through a radical polymerization at 65 degrees C using methacrylic acid and trimethylolpropane trimethacrylate in the presence of template molecule (RAC or DM-RAC). The prepared polymer was characterized by scanning electron microscopy and Fourier transform infrared spectroscopy and tested in MISPE experiments. The polymers were used in testing conditions, revealing a high retention capacity of RAC-MISPE to retain RAC either in the presence of similar concentrations of RAC and DM-RAC precursor (96.9%, RSD 6.6%) and in the presence of a large excess of precursor (90%, RSD 4.6%) in the loading solution. Starting from these promising results, preliminary studies for selective purification of [C-11]Raclopride using this RAC-MISPE were performed and, while generally confirming the selectivity capacity of the polymer, revealed challenging applicability to the current synthetic process, mainly due to high backpressures and long elution times

Photoreduction of Carbon Dioxide to Formic Acid in Aqueous Suspension: A Comparison between Phthalocyanine/TiO2 and Porphyrin/TiO2 Catalysed Processes

Composite materials prepared by loading polycrystalline TiO2 powders with lipophilic highly branched Cu(II)- and metal-free phthalocyanines or porphyrins, which have been used in the past as photocatalysts for photodegradative processes, have been successfully tested for the efficient photoreduction of carbon dioxide in aqueous suspension affording significant amounts of formic acid. The results indicated that the presence of the sensitizers is beneficial for the photoactivity, confirming the important role of Cu(II) co-ordinated in the middle of the macrocycles. A comparison between Cu(II) phthalocyanines and Cu(II) porphyrins indicated that the Cu(II)- phthalocyanine sensitizer was more efficient in the photoreduction of CO2 to formic acid, probably due to its favorable reduction potential

Photocontrolled wettability changes in polymer microchannels doped with photochromic molecules

The authors demonstrate the possibility to control the fluid flow inside microfluidic networks by photoresponsive capillaries. The approach relies on the use of photochromic molecules undergoing reversible changes in their polarity when irradiated with light of specific wavelength, thus varying the wettability of cyclic olefin copolymer microchannels. The realized photoresponsive elements exhibit a decrease up to 20° between the water contact angles of the native and the irradiated surfaces, which could be exploited for enhancing the penetration flow rate of fluids inside microfluidic channels up to 25%. The photocontrollable microfluidic circuitry presents on-off valve behavior, allowing or blocking liquid filling processes on the base of optical control, thus allowing one to manipulate liquid flow within microfluidic networks without mechanical actuation parts

Magnesium and its alloys as degradable biomaterials : Corrosion studies using potentiodynamic and EIS electrochemical techniques

Magnesium is potentially useful for orthopaedic and cardiovascular applications. However, the corrosion rate of this metal is so high that its degradation occurs before the end of the healing process. In industrial media the behaviour of several magnesium alloys have been probed to be better than magnesium performance. However, the information related to their corrosion behaviour in biological media is insufficient. The aim of this work is to study the influence of the components of organic fluids on the corrosion behaviour of Mg and AZ31 and LAE442 alloys using potentiodynamic, potentiostatic and EIS techniques. Results showed localized attack in chloride containing media. The breakdown potential decreased when chloride concentration increased. The potential range of the passivation region was extended in the presence of albumin. EIS measurements showed that the corrosion behaviour of the AZ31 was very different from that of LAE442 alloy in chloride solutions.Facultad de Ciencias Exacta

cardanol based green nanovesicles with antioxidant and cytotoxic activities

ABSTRACTThis manuscript describes the preparation of green nanovesicles by using cardanol as renewable starting material with embedded minor amounts of phthalazines, a class of heterocyclic bioactive compounds. The nanovesicles were prepared by stirring induced self-assembly in aqueous medium without involvement of any organic solvent. Dynamic light scattering studies and transmission electron microscopy revealed the formation of nanostructure with an average diameter in the range of 227–375 nm and a well defined spherical morphology. Potential antioxidant activity of nanovesicles were evaluated for the first time by 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging assay and bleomycin-dependent DNA damage. Moreover, their cytotoxic effects were also investigated by 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay on different tumour cell lines. Unloaded nanovesicles showed moderate antioxidant and antitumoural activity that was further enhanced particularl..