Oil Media on Paper: Investigating the Effect of Linseed Oils on Pure Cellulosic Paper Supports. A Research Matter of Damage Assessment

Oil media on paper, such as oil paintings, sketches, prints, and books, occasionally present problems associated with the effect of oil medium on the paper support, raising a composite matter of condition assessment as it depends on several factors. The present work examines the effect of linseed oil on paper and, in particular, the changes caused by three types of linseed oil on the optical, morphological, mechanical, and chemical properties of pure cellulosic paper, employing mock-ups submitted to artificial ageing in controlled conditions of relative humidity and temperature in airtight vessels. The study involved colorimetry, opacity, tensile strength, pH measurements, SEM, FTIR, and VOC analysis with GC-MS. Processing of the results has so far indicated that thermal-humid ageing caused the gradual darkening of the oil-impregnated mock-ups, as well as alterations in opacity, intense fall of pH values, and severe reductions in tensile strength, while linseed oil processing during manufacture has a significant impact. FTIR spectra have indicated that chemical changes upon ageing are in accordance with those of optical and mechanical changes, while VOC emissions are mostly associated with the drying and degradation of the different types of linseed oil

Oil Media on Paper: Investigating the Effect of Linseed Oils on Lignocellulosic Paper Supports

Condition assessment of works of art created with oil media on paper could be a complex matter when presenting problems of damage due to the absorption of oil binders by the paper support, since they depend on several factors and occur in variable conditions. The present work refers to the results of an investigation on the effect of linseed oils on the color, opacity, morphology, tensile strength, and chemical properties of lignocellulosic papers, in comparison to that of pure cellulosic papers. Lignocellulosic papers are involved in research on new, yet significant, parameters that might influence the behavior of the oil-impregnated areas of the supports upon aging. The research was applied to mock-ups, made of two types of lignocellulosic paper impregnated with three types of linseed oil and subjected to accelaratated ageing in specific conditions of relative humidity and temperature in closed environment. The research involved colorimetry, opacity, tensile strength, pH measurements, SEM, FTIR, and VOC analysis with GC-MS. The results indicated that thermal-humid ageing caused the gradual darkening of the oil-impregnated mock-ups, alterations in opacity, and decrease of pH values, depending mainly on the formulation of linseed oil, as well as a reduction in tensile strength. FTIR analysis results indicated that the chemical changes that occur upon ageing supported the recorded optical and mechanical alterations, while VOC emissions are both associated with the paper type and the kinetics of degradation of the different types of linseed oil

Inverted Perovskite Photovoltaics Using Flame Spray Pyrolysis Solution Based CuAlO2/Cu−O Hole-Selective Contact

We present the functionalization process of a conductive and transparent CuAlO2/Cu-O hole-transporting layer (HTL). The CuAlO2/Cu-O powders were developed by flame spray pyrolysis and their stabilized dispersions were treated by sonication and centrifugation methods. We show that when the supernatant part of the treated CuAlO2/Cu-O dispersions is used for the development of CuAlO2/Cu-O HTLs the corresponding inverted perovskite-based solar cells show improved functionality and power conversion efficiency of up to 16.3% with negligible hysteresis effect

La conservazione preventiva del patrimonio librario come possibile alternativa al restauro tradizionale

The present paper focuses on the close relation between library collections and their preservation environment, aiming, in particular, at highlighting the importance of promoting and sustaining the monitoring. The paper proposes some simple and ready-to-use technologies – smart monitoring – to prevent future damages

Versions, variants or distortions of tools ?

Choulis Konstantinos. Versions, variants or distortions of tools ?. In: Gazette du livre médiéval, n°50. Printemps 2007. pp. 51-55

Study and analysis of the design and construction parameters of reverse osmosis desalination plants

95 σ.Οι παγκόσμιες ανάγκες σε νερό δεν μπορούν πλέον να καλυφθούν λόγω της συνεχούς μείωσης των διαθέσιμων υπόγειων και επιφανειακών υδάτων σε συνδυασμό με την ταυτόχρονη ρύπανσή τους σε ανεπανόρθωτο βαθμό. Το πρόβλημα αντιμετωπίζεται με 2 τρόπους. Η πρώτη και φθηνότερη επιλογή είναι η επεξεργασία των διαθέσιμων ρυπασμένων ή/και υφάλμυρων υπόγειων και επιφανειακών υδάτων. Η δεύτερη και ακριβότερη επιλογή είναι η παραγωγή καθαρού νερού μέσω επεξεργασίας του νερού της θάλασσας, το οποίο και είναι απεριόριστο. Η πιο αποτελεσματική τεχνολογία που εφαρμόζεται και στις δύο παραπάνω περιπτώσεις είναι η αντίστροφη όσμωση. Προτού κάποιος μηχανικός ασχοληθεί με την χρήση, την εγκατάσταση, την κατασκευή και τον σχεδιασμό ενός συστήματος επεξεργασίας νερού, θα πρέπει πρώτα να γνωρίζει ποιο είναι το πρόβλημα του νερού, ποιο είναι το τελικό επιθυμητό αποτέλεσμα, ποιες είναι όλες οι πιθανές τεχνολογίες που μπορούν να χρησιμοποιηθούν και ποια τα χαρακτηριστικά της καθεμίας. Αφού καλύψει τα παραπάνω ζητήματα, κατόπιν καταλήγει στο βέλτιστο συνδυασμό μεθόδων για την εκάστοτε περίπτωση προβλήματος. Η εργασία αναλύει όλα τα ζητήματα που σχετίζονται με μονάδες επεξεργασίας νερού με αντίστροφη όσμωση. Αρχικά αναλύονται λεπτομερώς όλα τα επί μέρους τμήματα μιας τέτοιας εγκατάστασης που είναι τα εξής: υδροληψία, προ-επεξεργασία υδάτων, τμήμα αντίστροφης όσμωσης, μετα-επεξεργασία υδάτων. Σκοπός της εργασίας είναι η περιγραφή των βημάτων που πρέπει να ακολουθηθούν για την ορθή εκπόνηση μιας μελέτης σχεδιασμού και κατασκευής μιας μονάδας αφαλάτωσης με αντίστροφη όσμωση.The global demand for water can no longer be met due to the constant reduction of the available groundwater and surface water sources and their simultaneous contamination to an irreversible degree. The problem is solved by 2 ways. The first and cheapest option is to treat the available polluted and / or brackish groundwater and surface water. The second and most expensive option is to produce clear freshwater by treating seawater, given that seawater is unlimited. The reverse osmosis is the most effective technology which is applied in both cases. When an engineer has to deal with the design, the construction, the installation and the operation of a water treatment system, first of all he has to be able to answer the following questions: • What is the problem of the water? • What is the desired quality and quantity of the product water? • Which are all the possible technologies that can be applied effectively and what are the characteristics of each one? After answering these questions, the engineer decides which the best combination of methods for each case of problem is. This dissertation analyzes all the parameters related to reverse osmosis desalination plants. There is a full analysis of every unit of such facilities: water intakes, water pre-treatment unit, reverse osmosis unit and water post-treatment unit. The purpose of this dissertation is to describe the steps that must be followed for the proper preparation of a design and construction study of a reverse osmosis desalination plant.Κωνσταντίνος Ι. Χούλη

Photovoltaic analysis of the effects of PEDOT:PSS-additives hole selective contacts on the efficiency and lifetime performance of inverted organic solar cells

Solution processed inverted organic photovoltaics (OPVs) usually use (Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) PEDOT:PSS derivatives as hole selective contact. In this study the effect of different PEDOT:PSS formulations, Al4083, PH and PH500 in inverted structured OPVs is investigated. Through detailed device physics analysis PEDOT:PSS PH is proposed as most suitable hole selective contact for inverted OPVs device function. Furthermore, PEDOT:PSS PH hole selective contact is treated with 3 different wetting agents, Zonyl FS-300 fluorosurfactant (Zonyl), 2,5,8,11-tetramethyl-6-dodecyn-5,8-diol ethoxylate (Dynol) and Zonyl:Dynol mixture and the corresponding non-encapsulated inverted OPVs investigated under accelerated humidity lifetime conditions. The inverted OPVs incorporating PEDOT:PSS:Zonyl hole selective contact shown limitations on humidity lifetime performance due to the poorest adhesion properties of Zonyl-treated PEDOT:PSS PH compared with Dynol and Zonyl/Dynol mixture treaded PEDOT:PSS PH

Correlation between thickness, conductivity and thermal degradation mechanisms of PEDOT:PSS films

D.c. conductivity σ and thermal degradation measurements on PEDOT:PSS films of different thicknesses d  =  50, 120 and 180 nm are reported. The experimental results are consistent with a hopping type carrier transport. For the films with thickness d  =  50 nm, which consist of almost one single layer of PEDOT:PSS conductive grains, the conductivity and the heat aging are consistent with a hopping transport in a granular metal type structure. However, for films with d  =  120 and 180 nm, in which many conductive grains constitute the film thickness, a completely different behaviour is exhibited. An explanation of this is propose

The influence of additives in the stoichiometry of hybrid lead halide perovskites

We investigate the employment of carefully selected solvent additives in the processing of a commercial perovskite precursor ink and analyze their impact on the performance of organometal trihalide perovskite (CH3NH3PbI3-xClx) photovoltaic devices. We provide evidence that the use of benzaldehyde can be used as an effective method to preserve the stoichiometry of the perovskite precursors in solution. Benzaldehyde based additive engineering shows to improve perovskite solid state film morphology and device performance of CH3NH3PbI3-xClx based solar cells