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Current conservation approaches are shifting toward small, tailored, and less invasive interventions. Therefore the problems and best practices for conservators are becoming increasingly mobile. The future of art preservation heating systems will be with “intelligent” devices that are portable, flexible, reliable, and cost-effective. In this scenario, flexible heaters are becoming the preferred device for the application of heat in restoration since they can be shaped in different geometries and sizes, are easy to be transported and can be applied in the most versatile way with other treatment devices. Moreover, such devices can be applied also for in situ treatments, for instance, in emergency interventions. The development of these flexible devices comes from the past and, therefore, has a long history. To provide the reader with a comprehensive description of most innovative heating devices for art conservation, this chapter provides a brief history on how such devices evolved from the beginning to now, with the final aim of understanding the technological challenges and issues that allowed to continuously improve traditional heat tables and wound wire–based blankets toward the creation of innovative carbon nanotubes (CNTs)-based devices. After an historical investigation of heating devices, mostly based on heat tables, the chapter focuses on current technologies where nanomaterials are increasingly being used to boost the heating performance in several fields of application. Finally this work describes the main outcomes of a recent European Project, which applied CNTs-based coating on flexible substrates to create the first prototypes of intelligent mobile heaters to be adopted extensively by conservators. A number of applications of this new kind of device are eventually proposed and discussed.

Alfacalcidol and paricalcitol are vitamin D analogs used for the treatment of secondary hyperparathyroidism in patients with chronic kidney disease, but have known dose-dependent side effects that cause hypercalcemia and hyperphosphatemia. In this investigator-initiated multicenter randomized clinical trial, we originally intended two crossover study periods with a washout interval in 86 chronic hemodialysis patients. These patients received increasing intravenous doses of either alfacalcidol or paricalcitol for 16 weeks, until parathyroid hormone was adequately suppressed or calcium or phosphate levels reached an upper threshold. Unfortunately, due to a period effect, only the initial 16-week intervention period for 80 patients was statistically analyzed. The proportion of patients achieving a 30% decrease in parathyroid hormone levels over the last four weeks of study was statistically indistinguishable between the two groups. Paricalcitol was more efficient at correcting low than high baseline parathyroid hormone levels, whereas alfacalcidol was equally effective at all levels. There were no differences in the incidence of hypercalcemia and hyperphosphatemia. Thus, alfacalcidol and paricalcitol were equally effective in the suppression of secondary hyperparathyroidism in hemodialysis patients while calcium and phosphorus were kept in the desired range.

In this work, the elastic properties of melts of polycarbonate (PC)/multi-wall carbon nanotubes (MWCNT) composites were studied by means of rotational and capillary rheometry. Linear viscoelastic shear oscillations combined with simultaneous electrical measurements, creep recovery experiments in shear and extrudate swell measurements were performed. The application of the fractional Zener model for the phenomenological description of the viscoelastic properties of PC/MWCNT composites in the linear regime is discussed. The modulus of the spring of the fractional Zener model is a measure of elasticity and increases with carbon nanotubes concentration. The results of creep recovery experiments reveal that the microstructure strongly influenced the viscosity and the reversible deformation of the nanocomposites. Below the rheological percolation threshold, agglomeration of carbon nanotubes generally led to an increase of the reversible deformation up to a maximum value. Above the rheological percolation threshold, a larger concentration of carbon nanotubes caused a decrease of the recoverable deformation. As revealed by capillary rheometry, the extrudate swell of the PC/MWCNT composites at shear rates above 100 s − 1 was lower than the extrudate swell of neat polycarbonate which indicates the decrease of reversible deformation caused by the addition of MWCNT in capillary flows (large stress regime). The experimental data are discussed in the context of the current understanding of the rheological properties and the microstructure of polymer composites with carbon nanotubes.

A method of carbon nanotubes (CNTs) oxidation at room temperature using ozone with added water vapor is described. The resulting CNTs were characterized by Fourier transform infrared, X-ray photoelectron spectroscopy, and scanning and transmission electron microscopy. These show that more oxygenated functional groups could be grafted onto the CNT surfaces due to the addition of water vapor, compared to traditional approaches in which high density of ozone is required. The existed hydroxyl radicals in the water vapor/ozone mixture is considered to be responsible for the increased CNT oxidizing degree.

The influence of molar mass and temperature on the formation of networks of multiwalled carbon nanotubes (MWCNT) in oscillatory shear flows was investigated. Combined rheological and electrical investigations were performed using composites with 0.5–5.0 wt% MWCNT in a low- and a high-viscosity polycarbonate (PC) at 190 °C and 250 °C. The objective of this work was to study the dynamics of the simultaneous formation of electrical and rheological networks by taking into account the superposition of (i) network breakup by the applied shear field and (ii) the diffusion-controlled clustering of carbon nanotubes. The formation (i.e. the buildup) of electrical and rheological networks proceeds more rapidly for a lower-viscosity matrix and at higher temperatures, whereas breakup of the electrical network is more pronounced at lower temperatures because of a larger stress-transfer between polymer matrix and MWCNT network. Sinusoidal shear deformation results in an oscillatory electrical conductivity with decreasing average value at large shear amplitudes, indicating that the electrical nanotubes network consists of weakly bonded carbon nanotube clusters which can be easily released and reformed. These data also show that MWCNT–MWCNT bonds can be reversibly deformed up to a maximum deformation. The latter experimental result precises the current understanding of electrical carbon nanotubes networks.

Zusammenfassung Bei sieben Ponys (O 185 kg Lebendmasse) wurde der Einflus steigender Proteinmengen (Sojaeiweis; 0,98 bis 4,26 g/kg Lebendmasse bzw. 3,68 bis 15,8 g/kg LM0,75) auf die Verdauungsvorgange sowie den Wasser- und Mineralstoffumsatz uberpruft. Wahrend der erhohten Proteinzufuhr nahm der Kotwassergehalt geringgradig, die Gesamtindikanproduktion erheblich zu. Bei zwei Pferden traten Rehe-Erkrankungen auf. Der Harnstoffgehalt im Blut stieg von durchschnittlich 38 auf 88 mg/dl, die Wasseraufnahme von durchschnittlich 37 auf 103 ml/kg Lebendmasse an. Daruber hinaus fiel wahrend der hochsten Proteingabe eine erhebliche (nicht signifikante) Steigerung der renalen P-Exkretion auf (die zu einer negativen P-Bilanz fuhrte). Bei Pferden, die im Erhaltungsstoffwechsel stehen, sollte nicht mehr als das Dreifache des Proteinerhaltungsbedarfes, der rd. 3 g verdaul. Rohprotein/kg LM0,75 betragt, gefuttert werden. Summary Effects of giving excess protein to horses In 7 ponies (mean body wt. 185 kg) the effects of protein rations augmented with soya protein (0.98–4.26 g/kg live weight or 3,68–15.8 g/kg LW0,75) on digestive changes and on water and mineral exchange were studied. During the high protein feeding the water content of the faeces rose slightly and total indican production markedly. Two of the ponies developed signs of laminitis. Blood urea rose from, on average, 38 to 88 mg/dl and water intake from 37 to 103 mg/kg body weight. In addition, during the highest protein feeding, there was a marked but not significant rise in renal P excretion which led to a negative P balance. In horses on a maintenance diet it is not advisable to give more than three times the protein maintenance requirement, which is about 3 g digestible crude protein / kg live weight0.75. Resume Consequences d'un surdosage de proteines chez le cheval On a examine chez 7 poneys (poids moyen de 185 kg) l'influence de rations proteiques augmentees (proteine de soja: 0,98 a 4,26 g/kg de poids, respectivement 3,68 a 15,8 g/kg LM0,75) sur les processus de la digestion et les echanges eau-mineraux. Le taux aqueux des matieres fecales n'a augmente que tres faiblement et la production totale d'indican s'est fortement elevee durant l'apport augmente de proteines. Deux chevaux ont presente une fourbure. Le taux d'uree dans le sang est monte en moyenne de 38 a 88 mg/dl, l'absorption d'eau en moyenne de 37 a 103 ml/kg de poids. On a constate une nette augmentation (non significative) de l'excretion — P renale durant le regime proteique le plus eleve qui a conduit a un bilan — P negatif. On ne devrait pas donner plus que trois fois la dose proteique d'entretien qui conprend 3 g de proteines digestibles/kg LM0,75 a des chevaux en metabolisme d'entretien. Resumen Efectos de suministros excesivos de proteinas en el caballo Se verifico en siete ponys (O 185 kg masa viva) el influjo de cantidades crecientes de proteinas (proteina de soja; 0,98 hasta 4,26 g/kg masa viva resp. 3,68 hasta 15,8 g/kg MV0,75) sobre los procesos digestivos asi como el metabolismo del agua y mineral. Durante la aportacion proteica aumentada se acrecentaba en grado escaso el contenido en agua del estiercol, mientras que bastante la produccion de indican total. En dos caballos aparecieron pododermatitis. El contenido de urea en sangre aumento de un promedio de 38 a 88 mg/dl, la toma de agua de un promedio de 37 a 103 ml/kg masa viva. Ademas llamo la atencion durante la administracion maxima de proteina el aumtento considerable (no significante) de la excrecion renal de P (el cual conducia a un balance negativo del P). A los caballos que se encuentran en el metabolismo de conservacion, no se les debia facilitar nada mas que el triple de la demanda proteica de conservacion, la cual asciende aprox a 3 g de proteina bruta/kg MV0,75.