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1.
Environ Sci Pollut Res Int ; 30(47): 104633-104639, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37707725

ABSTRACT

The identification of the degradation products in objects of cultural significance, including musical instruments (e.g., a piano), is a key issue for the preservation and valorisation processes of cultural heritage. The aim of this study is to characterize the degradation products of lead weights from an important Steinway & sons piano using a multi-analytical approach that includes ionic chromatography (IC), X-ray diffraction (XRD) and Fourier transform-infrared (FTIR) spectroscopy analyses. These techniques allowed us to identify hydrocerussite as the main degradation product on the superficial layer of lead weights, followed by lead acetate and formate. Moreover, accelerated corrosion experiments in closed environments were performed under acetic and formic acid atmospheres to evaluate the development of lead acetate and formate over time. Exposure of lead weights to formic and acetic acid vapours leads to the prevalent formation of basic lead formate, which promotes the formation of hydrocerussite. These results can help to limit the degradation of these piano components and consequently preserve the sound of the piano itself.


Subject(s)
Lead , Nuclear Family , Acetic Acid , Formates
2.
Water Res ; 231: 119608, 2023 Mar 01.
Article in English | MEDLINE | ID: mdl-36709564

ABSTRACT

The use of surfactants represents a viable strategy to boost the removal yield of Dense Non-Aqueous Phase Liquids (DNAPLs) from groundwater and to shorten the operational timing of the remediation process. Surfactants, in general, help in reducing the interfacial tension at the DNAPL/water interface and enhance the solubility of the pollutant in the water phase through the formation of dispersed systems, such as micelles and emulsions. In this paper, we show that a suitable choice of a surfactant, in this case belonging to the bio-degradable class of ethoxylated alcohols, allows for the formation of hydrodynamic interfacial instabilities that further enhances the dissolution rate of the organic pollutant into the water phase. In a stratified configuration (denser organic phase at the bottom and lighter water phase on top), the instabilities appear as upward-pointing fingers that originate from the inversion of the local density at the interface. This inversion stems from the synergetic coupling of two effects promoted by the ethoxylated surfactant: i) the enhanced co-solubility of the DNAPL into the water (and viceversa), and (ii) the differential diffusion of the DNAPL and the surfactant in the aqueous phase. By dissolving into the DNAPL, the surfactant also reduces locally the surface tension at the liquid-liquid interface, thereby inducing transversal Marangoni flows. In our work, we carefully evaluated the effects of the concentration of different surfactants (two different ethoxylated alcohols, sodium dodecylsulphate, cetyltrimethyl ammonium bromide, N-tetradecyl-N, N-dimethylamine oxide and bis(2-ethylhexyl) sulfosuccinate sodium salt) on the onset of the instabilities in 3 different DNAPLs/water stratifications, namely chloroform, trichloroethylene and tetrachloroethylene, with a special emphasis on the trichloroethylene/water system. By means of a theoretical model and nonlinear simulations, supported by surface tension, density and diffusivity measurements, we could provide a solid explanation to the observed phenomena and we found that the type of the dispersed system, the solubility of the DNAPL into the water phase, the solubility of the surfactant in the organic phase, as well as the relative diffusion and density of the surfactant and the DNAPL in the aqueous phase, are all key parameters for the onset of the instabilities. These results can be exploited in the most common remediation techniques.


Subject(s)
Trichloroethylene , Water Pollutants, Chemical , Solubility , Water Pollutants, Chemical/analysis , Alcohols , Surface-Active Agents , Sodium
3.
J Environ Manage ; 327: 116881, 2023 Feb 01.
Article in English | MEDLINE | ID: mdl-36462484

ABSTRACT

Coffee consumption is concentrated in the "Global North", while production is mainly located in the "Global South". This trade-driven dependency leads to the exploitation of natural resources. As an export-oriented cash crop, such dependency jeopardizes the existence of a fair distribution of the risks and revenues among all the actors taking part in its globalized supply chain. Coffee trees are mainly rain-fed and only partly irrigated. However, the increasing global coffee demand led to higher consumption of freshwater, which can exacerbate the stressed condition of already stressed water basins. This study quantifies the impact of global coffee consumption on water scarcity, considering the larger system made of producer and consumer countries. The global displacement of such impact is driven by consumer preferences. We found that the US, EU and Asian countries' coffee consumption create impact on water scarcity mostly in African and South American countries, which is also representative of the economic disparities existing behind the global trade flows. Climate change will likely affect the varieties currently preferred by global consumers. Therefore, immediate environmental sustainability actions including water resource preservation are necessary to face current and future challenges.


Subject(s)
Water Insecurity , Water Supply , Water Resources , Fresh Water , Water
4.
Molecules ; 27(23)2022 Dec 03.
Article in English | MEDLINE | ID: mdl-36500616

ABSTRACT

Unlike halides, where the kosmotropicity decreases from fluoride to iodide, the kosmotropic nature of halates apparently increases from chlorate to iodate, in spite of the lowering in the static ionic polarizability. In this paper, we present an experimental study that confirms the results of previous simulations. The lyotropic nature of aqueous solutions of sodium halates, i.e., NaClO3, NaBrO3, and NaIO3, is investigated through density, conductivity, viscosity, and refractive index measurements as a function of temperature and salt concentration. From the experimental data, we evaluate the activity coefficients and the salt polarizability and assess the anions' nature in terms of kosmotropicity/chaotropicity. The results clearly indicate that iodate behaves as a kosmotrope, while chlorate is a chaotrope, and bromate shows an intermediate nature. This experimental study confirms that, in the case of halates XO3-, the kosmotropic-chaotropic ranking reverses with respect to halides. We also discuss and revisit the role of the anion's polarizability in the interpretation of Hofmeister phenomena.


Subject(s)
Chlorates , Water , Anions , Sodium Chloride , Temperature , Iodates
5.
J Phys Chem B ; 124(43): 9658-9667, 2020 10 29.
Article in English | MEDLINE | ID: mdl-32989990

ABSTRACT

We studied the effect of spectator ions in the prototype of far-from-equilibrium self-organized chemical systems, the Belousov-Zhabotinsky (BZ) reaction. In particular, we investigated the specific ion effect of alkali metal cations, connoted for their kosmotropic and chaotropic properties. By means of combined experimental and numerical approaches, we could show a neat and robust evidence for the Hofmeister effect in this system. Spectator cations induce a marked increment of the induction period that preludes regular oscillations and decrease the oscillation amplitude following the sequence Li+ < Na+ ≪ K+ ∼ Cs+. These ions affect the system kinetics by interfering in the interaction between the oxidized form of the catalyst and the organic substrate, responsible for resetting the BZ system to pre-autocatalytic (reduced) conditions. The specific ion effect on these key reactive steps is systematically characterized and correlated with different parameters which describe the interaction of the cations with the solvent.

6.
Phys Chem Chem Phys ; 19(48): 32235-32241, 2017 Dec 13.
Article in English | MEDLINE | ID: mdl-29188267

ABSTRACT

In this paper we show that the active interplay of nonlinear kinetics and transport phenomena in a chemical oscillator can be exploited to induce and control chaos. To this aim we use as a model system the ferroin-catalysed Belousov-Zhabotinsky (BZ) oscillating reaction, which is known to evolve to characteristic chaotic transient dynamics when carried out under batch and unstirred conditions. In particular, chemical chaos was found to appear and disappear by following a Ruelle-Takens-Newhouse (RTN) scenario. Here we use medium viscosity as a bifurcation parameter to tune the reaction-diffusion-convection (RDC) interplay and force the reaction in a specific sequence of dynamical regimes: either (i) periodic → quasi-periodic → chaotic or (ii) periodic → quasi-periodic or (iii) only periodic. The medium viscosity can be set by adding different amounts of surfactant (sodium dodecyl sulphate), known to have a little impact on the reaction mechanism, above its critical micelle concentration. Experimental results are supported by means of numerical simulations of a RDC model, which combines self-sustained oscillations to the related chemically-induced buoyancy convection.

7.
Food Chem ; 136(3-4): 1426-8, 2013 Feb 15.
Article in English | MEDLINE | ID: mdl-23194544

ABSTRACT

This paper reports the results of a preliminary study on the characterization of parameters influencing formation of acrylamide in fried potatoes, from biological cultivation. The formation of acrylamide was investigated in relation to frying in biological extra virgin olive oil and commercial seed oil. Three different cultivars (Rossa di Colfiorito, Quarantina bianca genovese and Kennebec) were chosen. Asparagine, glucose, fructose and sucrose concentrations were determined in potato slice before frying, while acrylamide content was analysed by LC-ESI-MS/MS in the slices fried in seed and extra virgin olive oil. The Kennebec cultivar showed differences in its potential for acrylamide formation, which was primarily related to its relatively high asparagine and reducing sugars contents, respect the other local cultivars (particulary Quarantina). Values of acrylamide below detection limit (LOD) were found in Quarantina bianca genovese cultivar samples fried in extra virgin olive oil and peanuts seed oil and higher in peanuts seed oil fried potatoes of Kennebec cultivar.


Subject(s)
Acrylamide/analysis , Cooking/methods , Solanum tuberosum/chemistry , Agriculture , Chromatography, Liquid , Hot Temperature , Mass Spectrometry , Solanum tuberosum/economics
8.
Chaos ; 22(3): 037109, 2012 Sep.
Article in English | MEDLINE | ID: mdl-23020500

ABSTRACT

The interaction of traveling waves, with both Marangoni and buoyancy driven flows, can generate an extraordinary rich array of patterns ranging from stationary structures to chaotic waves. However, the inherent complexity of reaction-diffusion-convection (RDC) systems makes the explanation of the patterning mechanisms very difficult, both numerically and experimentally. In this paper, we describe the appearance of segmented waves in a shallow layer of an excitable Belousov-Zhabotinsky solution. The segmentation process was found to be dependent both on the depth of the solution and on the excitability of the reaction. We caught the essential features of the system through a RDC model, where the chemical waves were coupled both with surface and bulk fluid motions and we found that by varying the excitability of the reaction, and in turn the wavelength of the chemical fronts, it is possible to create a sort of hydrodynamic resonance structures (corridors), which are responsible for the segmentation process.


Subject(s)
Convection , Models, Chemical , Diffusion , Probability , Rheology , Solutions , Time Factors
9.
Phys Chem Chem Phys ; 12(36): 11062-9, 2010 Sep 28.
Article in English | MEDLINE | ID: mdl-20672153

ABSTRACT

Chemical oscillations generated by the Belousov-Zhabotinsky reaction in batch unstirred reactors, show a characteristic chaotic transient in their dynamical regime, which is generally found between two periodic regions. Chemical chaos starts and finishes by following a direct and an inverse Ruelle-Takens-Newhouse scenario, respectively. In previous works we showed, both experimentally and theoretically, that the complex oscillations are generated by the coupling among the nonlinear kinetics and the transport phenomena, the latter due to concentration and density gradients. In particular, convection was found to play a fundamental role. In this paper, we develop a reaction-diffusion-convection model to explore the influence of the reagents consumption (BrO in particular) in the inverse transition from chaos to periodicity. We demonstrated that, on the route towards thermodynamic equilibrium, the reagents concentration directly modulates the strength of the coupling between chemical kinetics and mass transport phenomena. An effective sequential decoupling (reaction-diffusion-convection --> reaction-diffusion --> reaction) takes place upon the reagents consumption and this is at the basis of the transition from chaos to periodicity.

10.
J Theor Biol ; 265(4): 511-6, 2010 Aug 21.
Article in English | MEDLINE | ID: mdl-20493195

ABSTRACT

The Belousov-Zhabotinsky phenomenon is analyzed in a framework where the dynamics of dissipative structures outlined by Prigogine is implemented through the collective dynamics produced in liquid water by Quantum Electrodynamics, which has received recently some experimental support. A mechanism allowing the appearance of self-produced oscillations is suggested.


Subject(s)
Models, Chemical , Water/chemistry , Quantum Theory
11.
Math Biosci ; 222(1): 36-41, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19706297

ABSTRACT

This paper presents a novel approach to study in vivo cellular kinetics by the combined use of magnetic resonance (MR) spectroscopy and Odum's system modeling, which includes the entire process of substrate degradation and product formation. The experiment was conducted directly in the MR-probe, where microorganisms (Klebsiella planticola) were incubated with high (13)C-glucose and (13)C-xylose concentration. Sugar consumptions and (13)C-ethanol production were followed for 17 h and MR-spectra were acquired every 30min without external sampling. Fitting of data allowed evaluation of sugar degradation, ethanol formation, cell activation induced by substrates, as well as cell inhibition induced by ethanol. The dynamics related to the diauxic growth of the bacterium under study were analyzed in terms of different kinetic behaviors. This approach gives not only a good fit of theoretical to experimental results, but is able also to interpret the way substrates, cells and products interact with each other. The proposed methodology can be applied to different living systems to study complex novel mechanisms.


Subject(s)
Glucose/metabolism , Klebsiella/metabolism , Magnetic Resonance Spectroscopy/methods , Models, Biological , Xylose/metabolism , Ethanol/metabolism , Kinetics
12.
J Chem Phys ; 130(2): 024902, 2009 Jan 14.
Article in English | MEDLINE | ID: mdl-19154051

ABSTRACT

The transition to spatial-temporal complexity exhibited by spiral waves under the effect of gravitational field in the Belousov-Zhabotinsky reaction is numerically studied on the basis of spiral tip dynamics. Successive transformations in tip trajectories are characterized as a function of the hydrodynamical parameter and attributed to a Ruelle-Takens-Newhouse scenario to chaos. The analysis describes the emergence of complexity in terms of the interplay between the evolution of the velocity field and concentration waves. In particular, (i) by mapping the tip motion in relation to some hydrodynamical pseudopotentials, the general mechanism by which the velocity field affects the tip trajectory is pointed out, and, (ii) by comparing the dynamical evolutions of local and mean properties associated with the inhomogeneous structures and to the velocity field, a surprising correlation is found. The results suggest that the reaction-diffusion-convection (RDC) coupling addresses the system to some general regimes, whose nature is imposed by the hydrodynamical contribution. More generally, RDC coupling would be formalized as the phenomenon that governs the system and drives it to chaos.

13.
J Theor Biol ; 255(4): 404-12, 2008 Dec 21.
Article in English | MEDLINE | ID: mdl-18835281

ABSTRACT

This paper is an attempt to conceptualize pattern formation in self-organizing systems and, in particular, to understand how structures, oscillations or waves arise in a steady and homogenous environment, a phenomenon called symmetry breaking. The route followed to develop these ideas was to couple chemical oscillations produced by Belousov-Zhabotinsky reaction with confined reaction environments, the latter being an essential requirement for any process of Life. Special focus was placed on systems showing organic or lipidic compartments, which represent more reliable biomimetic matrices.


Subject(s)
Biomimetics , Models, Biological , Systems Biology/methods , Animals , Chemistry, Physical , Diffusion , Emulsions/chemistry , Lipid Bilayers/chemistry
14.
J Chem Phys ; 128(11): 111102, 2008 Mar 21.
Article in English | MEDLINE | ID: mdl-18361546

ABSTRACT

Direct numerical simulations of the transition process from periodic to chaotic dynamics are presented for two variable Oregonator-diffusion model coupled with convection. Numerical solutions to the corresponding reaction-diffusion-convection system of equations show that natural convection can change in a qualitative way, the evolution of concentration distribution, as compared with convectionless conditions. The numerical experiments reveal distinct bifurcations as the Grashof number is increased. A transition to chaos similar to Ruelle-Takens-Newhouse scenario is observed. Numerical results are in agreement with the experiments.

15.
J Environ Manage ; 86(2): 354-64, 2008 Jan.
Article in English | MEDLINE | ID: mdl-17110019

ABSTRACT

This work is part of a larger project, which aims at investigating the environmental sustainability of the Province of Siena and of its communes, by means of different indicators and methods of analysis. The research presented in this article uses ecological footprint and biocapacity as indicators to monitor the environmental conditions of the area of Siena, thus complementing previous studies carried out using Emergy, greenhouse gases balance and other methods. The calculations have been performed in such a way as to enable a disaggregation of the final results according to the classical categories of ecologically productive land and of consumption, but also according to citizen's and public administration's areas of influence. This information allows us to investigate in detail the socio-economic aspects of environmental resource use. Among the notable results, the Siena territory is characterized by a nearly breakeven total ecological balance, a result contrasting with the national average and most of the other Italian provinces. Furthermore, the analysis has been carried out at different spatial scales (province, districts and communes), highlighting an inhomogeneous territorial structure consisting of subareas in ecological deficit compensated by zones in ecological surplus.


Subject(s)
Ecosystem , Environmental Monitoring/methods , Conservation of Natural Resources , Energy-Generating Resources , Italy
16.
J Environ Manage ; 86(2): 407-18, 2008 Jan.
Article in English | MEDLINE | ID: mdl-17157978

ABSTRACT

Adaptive management as applied to tourism policy treats management policies as experiments that probe the responses of the system as human behavior changes. We present a conceptual systems model that incorporates the gap between observed and desired levels of the ecological footprint with respect to biocapacity. Addressing this gap (or 'overshoot') can inform strategies to increase or decrease visitation or its associated consumption in the coming years. The feedback mechanism in this conceptual model incorporates a gap between observed and desired ecological footprint levels of tourists and residents. The work is based on longer-term and ongoing study of tourism impacts and ecological footprint assessments from the SPIN-Eco Project. We present historical tourism and environmental data from the province of Siena, Italy and discuss the use of discrete, static environmental indicators as part of an iterative feedback process to manage tourism within biophysical limits. We discuss a necessary shift of emphasis from certain and static numbers to a process-based management model that can reflect slow changes to biophysical resources. As underscored by ecological footprint analysis, the energy and material use associated with tourism and local activity can erode natural capital foundations if that use exceeds the area's biological capacity to support it. The dynamic, and iterative process of using such indicators as management feedback allows us to view sustainability more accurately as a transition and journey, rather than a static destination to which management must arrive.


Subject(s)
Conservation of Natural Resources/methods , Ecosystem , Recreation , Travel , Environmental Monitoring/methods , Humans , Italy , Models, Theoretical
17.
Environ Sci Pollut Res Int ; 14(4): 227-8, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17668817

ABSTRACT

The aim of this paper is to propose a research framework, based on the joint use of three widely used methods: EMergy Evaluation (EME), Ecological Footprint Analysis (EFA) and Greenhouse Gas Inventory (GHGI), that are applied to assess the environmental sustainability of a region. The results of application of these methods to several Italian Provinces enabled us to compare their sustainability, and to test the methods with respect to sustainability requirements at local and global level. The outcomes suggest that the proposed framework provides an organic evaluation of regional systems based on key aspects, such as resources depletion, consumption patterns, waste production and absorption.


Subject(s)
Conservation of Natural Resources , Environment , Models, Theoretical , Humans , Italy
18.
Environ Monit Assess ; 133(1-3): 1-13, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17295112

ABSTRACT

This research proposes an integrated framework to investigate human-dominated systems and provide a basic approach to urban and regional studies in which the multiple interactions between economic and ecological processes are considered as a whole. Humans generate patterns of land use, infrastructures and other settings and redistribute ecosystem functions as flows of energy and matter for self-maintenance. To understand these emerging interactions between humans and ecological processes, human activities (e.g. transformation processes, land conversions, use of resources) and biophysical agents such as geomorphology, climate and natural cycles need to be considered. Emergy Analysis (spelled with an "m") is then used as an environmental accounting method to evaluate different categories of resource use with reference to their environmental cost. A case study of the Province of Cagliari (in the island of Sardinia, Italy) is reported and the procedure for allocating emergy flows, assigning them to districts and managing point data is discussed. Outcomes plotted on a map showed non-homogeneous spatial distribution of emergy flows throughout the region, suggesting the way ecosystem functions are affected and restructured by the human economy.


Subject(s)
Environmental Monitoring , Italy
19.
Ann Chim ; 95(3-4): 143-52, 2005.
Article in English | MEDLINE | ID: mdl-16485655

ABSTRACT

This paper presents the application of the eMergy evaluation, introduced by H.T. Odum as an efficient methodology of environmental accounting. The results of this analysis are a part of a wider sustainability assessment for the Province of Venice realized in 2003. Within a territorial sustainability analysis, it is necessary to implement an environmental accounting method, which is able: to precisely consider the boundaries of the investigated system (spatial scale); to arbitrarily separate the life of the investigated system into periods (temporal scale); to account for both economic and natural support to a given territorial system in order to implement a sustainable management of resources; to assess all the items supporting the system on the basis of a physical unit that is objective (while the traditional economic evaluation method is based on individual preferences, hence it is subjective). The Province of Venice is a very complex system due, on one hand, to the heavy and consolidated presence of industrial activity since the beginning of the 20th century and, on the other hand, to the principal natural ecosystem which characterizes it: the lagoon, the largest wetland in the Mediterranean Sea. The role of the lagoon, as a provider of resources and services is represented by the analysis of two aspects: the lagoon as an ecosystem on the basis of the evaluation of all flows that cyclically support its biotic activity and the lagoon as a productive system on the basis of the contribution of both natural and "economic" inputs that support human activity. In particular, the case of clam fishing will be presented to put on evidence the importance of natural inputs that are systematically neglected by the traditional accounting methodologies.


Subject(s)
Conservation of Natural Resources , Energy-Generating Resources , Fisheries , Animals , Bivalvia , Ecosystem , Humans , Italy , Seawater
20.
J Am Chem Soc ; 126(37): 11406-7, 2004 Sep 22.
Article in English | MEDLINE | ID: mdl-15366864

ABSTRACT

The present work deals with the spatially extended oscillatory Belousov Zhabotinsky reaction-diffusion system carried out in an anisotropic environment of phosphatidylcholines/water binary system, which presents layered aqueous domains separated by lipid bilayers. We report the occurrence of stable Turing patterns, spiral waves, and other exotic structures in phospholipids bilayers that are generally used as a models for cell plasma membranes.


Subject(s)
1,2-Dipalmitoylphosphatidylcholine/chemistry , Water/chemistry , Anisotropy , Cell Membrane/chemistry , Chemical Phenomena , Chemistry, Physical , Lipid Bilayers/chemistry , Scattering, Radiation , X-Rays
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