The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Piero Baglioni - One of the best experts on this subject based on the ideXlab platform.
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nanoparticles of calcium hydroxide for wood conservation the deacidification of the vasa warship
Langmuir, 2005Co-Authors: Rodorico Giorgi, David Chelazzi, Piero BaglioniAbstract:The seventeenth century Swedish warship Vasa represents a unique case in the study of ancient wrecks and a challenge for finding new methods for artifacts conservation. The presence of sulfuric acid inside the wooden structure of Vasa is one of the possible causes of Chemical Damage of the wood. During recent investigations, pH values below 2 were observed inside the wreck in several places. Neutralization treatments temporarily raised the surface pH about 6 units, but after a few months the pH reverted back to original values. In this study we show that wood from the Vasa warship can be deacidified by using a dispersion in 2-propanol of calcium hydroxide nanoparticles. These particles can penetrate into the wood allowing a very efficient deacidification. Alkaline nanoparticles are converted into calcium sulfate without mechanical stress to the wood's lumens. Additional applications produce an excess of alkaline nanoparticles that are converted into carbonate, an alkaline reservoir to protect the wood fro...
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nanoparticles of calcium hydroxide for wood conservation the deacidification of the vasa warship
Langmuir, 2005Co-Authors: Rodorico Giorgi, David Chelazzi, Piero BaglioniAbstract:The seventeenth century Swedish warship Vasa represents a unique case in the study of ancient wrecks and a challenge for finding new methods for artifacts conservation. The presence of sulfuric acid inside the wooden structure of Vasa is one of the possible causes of Chemical Damage of the wood. During recent investigations, pH values below 2 were observed inside the wreck in several places. Neutralization treatments temporarily raised the surface pH about 6 units, but after a few months the pH reverted back to original values. In this study we show that wood from the Vasa warship can be deacidified by using a dispersion in 2-propanol of calcium hydroxide nanoparticles. These particles can penetrate into the wood allowing a very efficient deacidification. Alkaline nanoparticles are converted into calcium sulfate without mechanical stress to the wood's lumens. Additional applications produce an excess of alkaline nanoparticles that are converted into carbonate, an alkaline reservoir to protect the wood from further acid attack. Artificial aging of Vasa wood demonstrates that nanoparticles facilitate protection of wood toward further acid degradation.
Slava V Rotkin - One of the best experts on this subject based on the ideXlab platform.
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two color spectroscopy of uv excited ssdna complex with a single wall nanotube photoluminescence probe fast relaxation by nucleobase autoionization mechanism
Nano Research, 2016Co-Authors: Tetyana Ignatova, Alexander Balaeff, Michael Blades, Ming Zheng, Peter Stoeckl, Slava V RotkinAbstract:DNA autoionization is a fundamental process wherein ultraviolet (UV)-photoexcited nucleobases dissipate energy by charge transfer to the environment without undergoing Chemical Damage. Here, single-wall carbon nanotubes (SWNT) are explored as a photoluminescent reporter for the study of the mechanism and rates of DNA autoionization. Two-color photoluminescence spectroscopy allows separate photoexcitation of the DNA and the SWNTs in the UV and visible range, respectively. A strong SWNT photoluminescence quenching is observed when the UV pump is resonant with the DNA absorption, consistent with charge transfer from the excited states of the DNA to the SWNT. Semiempirical calculations of the DNA-SWNT electronic structure, combined with a Green’s function theory for charge transfer, show a 20 fs autoionization rate, dominated by hole transfer. Rate-equation analysis of the spectroscopy data confirms that the quenching rate is limited by thermalization of the free charge carriers transferred to the nanotube reservoir. This approach has great potential for monitoring DNA excitation, autoionization, and Chemical Damage, both in vivo and in vitro.
Rodorico Giorgi - One of the best experts on this subject based on the ideXlab platform.
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nanoparticles of calcium hydroxide for wood conservation the deacidification of the vasa warship
Langmuir, 2005Co-Authors: Rodorico Giorgi, David Chelazzi, Piero BaglioniAbstract:The seventeenth century Swedish warship Vasa represents a unique case in the study of ancient wrecks and a challenge for finding new methods for artifacts conservation. The presence of sulfuric acid inside the wooden structure of Vasa is one of the possible causes of Chemical Damage of the wood. During recent investigations, pH values below 2 were observed inside the wreck in several places. Neutralization treatments temporarily raised the surface pH about 6 units, but after a few months the pH reverted back to original values. In this study we show that wood from the Vasa warship can be deacidified by using a dispersion in 2-propanol of calcium hydroxide nanoparticles. These particles can penetrate into the wood allowing a very efficient deacidification. Alkaline nanoparticles are converted into calcium sulfate without mechanical stress to the wood's lumens. Additional applications produce an excess of alkaline nanoparticles that are converted into carbonate, an alkaline reservoir to protect the wood fro...
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nanoparticles of calcium hydroxide for wood conservation the deacidification of the vasa warship
Langmuir, 2005Co-Authors: Rodorico Giorgi, David Chelazzi, Piero BaglioniAbstract:The seventeenth century Swedish warship Vasa represents a unique case in the study of ancient wrecks and a challenge for finding new methods for artifacts conservation. The presence of sulfuric acid inside the wooden structure of Vasa is one of the possible causes of Chemical Damage of the wood. During recent investigations, pH values below 2 were observed inside the wreck in several places. Neutralization treatments temporarily raised the surface pH about 6 units, but after a few months the pH reverted back to original values. In this study we show that wood from the Vasa warship can be deacidified by using a dispersion in 2-propanol of calcium hydroxide nanoparticles. These particles can penetrate into the wood allowing a very efficient deacidification. Alkaline nanoparticles are converted into calcium sulfate without mechanical stress to the wood's lumens. Additional applications produce an excess of alkaline nanoparticles that are converted into carbonate, an alkaline reservoir to protect the wood from further acid attack. Artificial aging of Vasa wood demonstrates that nanoparticles facilitate protection of wood toward further acid degradation.
Zhiguang Guo - One of the best experts on this subject based on the ideXlab platform.
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robust and muti repaired superhydrophobic surfaces via one step method on copper and aluminum alloys
Materials Letters, 2018Co-Authors: Zhiguang GuoAbstract:Abstract Facile preparation, mechanical durability, and fast regeneration are superior factors to expand the application of superhydrophobic surfaces. In this letter, a one-step immersion process was explored to construct a mechanically and Chemically durable superhydrophobic surface on copper and aluminum alloy, respectively, which can also be used when the surfaces were destroyed by mechanical stress or Chemical Damage. By immersion of the wrecked surfaces in the one-step regenerative solution or by the spray method and air dried, the substrates could be easily repaired, regaining the durable superhydrophobic properties.
David Chelazzi - One of the best experts on this subject based on the ideXlab platform.
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nanoparticles of calcium hydroxide for wood conservation the deacidification of the vasa warship
Langmuir, 2005Co-Authors: Rodorico Giorgi, David Chelazzi, Piero BaglioniAbstract:The seventeenth century Swedish warship Vasa represents a unique case in the study of ancient wrecks and a challenge for finding new methods for artifacts conservation. The presence of sulfuric acid inside the wooden structure of Vasa is one of the possible causes of Chemical Damage of the wood. During recent investigations, pH values below 2 were observed inside the wreck in several places. Neutralization treatments temporarily raised the surface pH about 6 units, but after a few months the pH reverted back to original values. In this study we show that wood from the Vasa warship can be deacidified by using a dispersion in 2-propanol of calcium hydroxide nanoparticles. These particles can penetrate into the wood allowing a very efficient deacidification. Alkaline nanoparticles are converted into calcium sulfate without mechanical stress to the wood's lumens. Additional applications produce an excess of alkaline nanoparticles that are converted into carbonate, an alkaline reservoir to protect the wood fro...
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nanoparticles of calcium hydroxide for wood conservation the deacidification of the vasa warship
Langmuir, 2005Co-Authors: Rodorico Giorgi, David Chelazzi, Piero BaglioniAbstract:The seventeenth century Swedish warship Vasa represents a unique case in the study of ancient wrecks and a challenge for finding new methods for artifacts conservation. The presence of sulfuric acid inside the wooden structure of Vasa is one of the possible causes of Chemical Damage of the wood. During recent investigations, pH values below 2 were observed inside the wreck in several places. Neutralization treatments temporarily raised the surface pH about 6 units, but after a few months the pH reverted back to original values. In this study we show that wood from the Vasa warship can be deacidified by using a dispersion in 2-propanol of calcium hydroxide nanoparticles. These particles can penetrate into the wood allowing a very efficient deacidification. Alkaline nanoparticles are converted into calcium sulfate without mechanical stress to the wood's lumens. Additional applications produce an excess of alkaline nanoparticles that are converted into carbonate, an alkaline reservoir to protect the wood from further acid attack. Artificial aging of Vasa wood demonstrates that nanoparticles facilitate protection of wood toward further acid degradation.