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• Protective multifunctional properties of archaeological textiles were achieved by coating methods. • Hydrophilic fabrics surface was developed using Ca-alginate/metal oxide NPs coating. • Super-hydrophobic fabrics surface was developed using SiO 2 NPs/ silicone rubber. Multifunctional protective surfaces for protecting archaeological textiles are of great interest in the conservation of the archaeological textile field. This study aims to provide protective properties against UV irradiation and microorganisms as well as self-cleaning properties to coloured archaeological textile surfaces without damaging their mechanical and colour properties. For the first time, two facile approaches for preparing the protective surfaces of archaeological textiles were developed to protect their surfaces from light radiation, microbes, and liquid stains. To achieve this aim, the study was carried out on empirically accelerated ageing dyed linen fabrics with madder natural dye, to get mockups as similar as possible to the archaeological ones (standard aged linen fabrics). In the first approach, the aged linen fabrics were coated with Ca-lignate@metal oxide NPs to fabricate hydrophilic fabrics' surfaces. In the second approach, the aged linen fabrics were coated with SiO 2 NPs/silicone rubber to fabricate hydrophobic fabrics' surfaces. The influence of the two coating approaches was evaluated on the performance and protective properties of coated aged linen samples, such as wettability, mechanical properties, coloration, UV protection, antimicrobial activity, and self-cleaning. Design innovative strategies for coating archaeological linen textiles surface to achieve protective multifunctional properties [Display omitted] [ABSTRACT FROM AUTHOR]

Cannabis sativa L. is a plant belonging to the Cannabaceae family known primarily for its recreational use due to the psychoactive properties of Δ9-tetrahydrocannabinol (THC). Despite this, several compounds belonging to the category of phytocannabinoids have shown in recent years a number of potentially promising therapeutic effects that have increased the interest in the pharmaceutical field towards this plant. However, the content of these compounds is very variable and influenced by different factors, such as growing conditions and time of the year. An indication of the status and age of Cannabis samples is provided by the content of CBN, a minor phytocannabinoid and degradation product of other phytocannabinoids, including THC. In this research work an innovative, solid state analytical approach has been developed to observe and evaluate the variations in the content of two phytocannabinoids (CBN and CBD) in Cannabis-derived products over time. In order to simulate the ageing of the Cannabis samples, an artificially accelerated ageing procedure has been developed and optimised by using high temperatures. The analyses were carried out using an innovative ATR-FTIR method for solid state analysis, enabling direct analysis of a solid sample without any pretreatment phase. This study has allowed the development of an innovative analytical approach for the evaluation of the age and state of conservation of Cannabis samples and may be a useful tool both in the industrial, pharmaceutical and forensic fields. [Display omitted] • An accelerated procedure for ageing studies of Cannabis products has been developed. • Microwave heating and oven heating were compared. • Samples were subjected to 70°C temperature in a humid oven environment. • The procedure used ATR-FTIR signals of CBN and CBD to evaluate concentration changes. • The 32-h results closely matched those from 12 months of natural aging. [ABSTRACT FROM AUTHOR]

• MMT/MMA/EA/HEMA nanocomposite was prepared by in situ microemulsion polymerization. • A novel paste was formed from the prepared nanocomposite and hydroxyapatite. • The artificial accelerated heat ageing was applied to the novel paste. • Different analytical techniques were used for the evaluation of the novel paste. • The novel paste is good and can be applied for gaps filling of archaeological bone. Montmorillonite MMT/ Methyl Methacrylate-Ethyl acrylate-2-hydroxyethyl methacrylate MMA/EA/HEMA terpolymeric nanocomposite was prepared through in-situ microemulsion polymerization. The produced nanocomposite was evaluated with hydroxyapatite, forming a novel paste for the gap filling of archaeological bones. Thermal ageing was used for the evaluation of prepared paste. Characterizations were carried out by FTIR; change of colour, Mechanical properties, SEM, X-Ray Diffraction (XRD), Antifungal activity, Density, porosity, water absorption, and wettability. The prepared MMT/ MMA-EA-HEMA terpolymer nanocomposite was produced in well-defined nanospheres with an average size of 144 nm. The results confirmed that the novel paste was very stable and had a great resistance against thermal ageing. All analysis and investigations proved that the addition of MMT/polymer nanocomposite gave good resistance to the reduction in contact angle, density, and resistance the rise in the porosity and water absorption during ageing. Microbiological studies showed that the novel paste had a good resistance against microorganisms. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • The papyrus writing-ground was analysed by near-infrared (NIR) spectroscopy. • Spectra were evaluated using PCA, HCA, PLS-DA, and SOM. • Cluster analysis and PLS-DA proved to be useful tools for distinguishing modern papyri from ancient papyri. • Natural and accelerated ageing did not affect the classification. • A PLS-DA classification model identifired recent Papyri samples by NIR even after accelerated ageing. Papyrus has been used for millennia to record information, for sophisticated works of art as well as mundane notes. The collection, identification, and translation of papyrus fragments therefore opens a gateway into the past. To aid the efforts to access the history recorded in papyri, we investigated the suitability of NIR spectroscopy to perform two tasks: One is to support the authentication of ancient papyri, by differentiation of papyri that were manufactured more recently and subjected to accelerated ageing to resemble the originals. The other is the extensive task to piece together papyrus fragments into readable texts again. In museums around the world, more than 100,000 ancient papyrus fragments still wait for their proper assembly, deciphering and publication. The papyrus writing-ground was analysed by near-infrared (NIR) spectroscopy, and the spectra were evaluated using principal component analysis (PCA), hierarchical cluster analysis (HCA), partial least squares discriminant analysis (PLS-DA), and self-organizing maps (SOM). Cluster analysis and PLS-DA proved to be useful tools for distinguishing modern papyri from ancient papyri which were provided by collections in Vienna and Leipzig. Neither natural nor accelerated ageing affected the classification. A PLS-DA classification model, constructed from NIR spectra of 89 model scores, detected recent Papyri samples with 100 % sensitivity and specificity, even after accelerated ageing. The identification of groups of fragments of ancient papyri based on NIR spectra and chemometry is not straightforward. HCA, which focuses on the differences between samples, only grouped the fragments of 4 out of 20 papyri correctly. SOM, which rather focuses on the similarities, grouped 6 sets of fragments correctly. An automated grouping of fragments remains difficult, since the fragments themselves are heterogeneous while similarities between unrelated ancient papyri can be large. [ABSTRACT FROM AUTHOR]

To maintain the permanence of a painting in a hanging scroll until subsequent repairs are made, inhibiting not only the deterioration of the painting and lining papers but also inhibiting decrease in the adhesiveness between them is important because the first lining process significantly influences the mechanical support to the painting paper by attachment. Several studies have been conducted on the deterioration attributed to each component of the lining system. This study evaluated the adhesiveness behaviour by peel strength in the lined complex depending on the painting and lining materials with varied concentrations, as well as the fibre type of the lining paper. The lined complex consisting of the untreated painting paper showed the highest initial peel strength owing to the significant cohesiveness of the wheat starch paste layer, which was attributed to the paper's higher wettability and permeability, even though substrate failure occurred with longer ageing times. Degradative materials such as Cu2+ attributed to pigments in the painting paper decomposed starch and decreased adhesiveness the fastest. Lined complexes coated with animal glue containing alum or Cu2+ in the painting paper maintained the lowest peel strength during ageing owing to lower wettability and permeability, resulting in interfacial failure between the animal glue and the wheat starch paste layer. In addition, adhesiveness varied with different fibre types of the lining paper, depending on combined factors such as fibre length, surface roughness, shape, and intensity of hydroxyl groups. Thus, variable conditions attributed to fibre characteristics, materials used for lining, and degradative products in the painting paper influenced the changes in adhesion and adhesiveness. This variation contributed to different lining effects that influenced the life expectancy of the hanging scroll and determined the efficiency of the subsequent repair work. • Long-term permanence of the complex of painting and lining paper assuming a Japanese hanging scroll. • Improving the lining effect by evaluating the adhesion and adhesiveness of lined complexes. • Different lining effects caused by the painting and lining materials and the fibre type of the lining paper. • Influence of fibre length, roughness, shape, and hydroxyl groups of the lining paper on wettability of adhesive. [ABSTRACT FROM AUTHOR]

• Thermal insulating mortars were exposed to different accelerated ageing procedures. • Ageing tests included elevated temperature, freeze–thaw and elevated relative humidity levels. • The ageing procedures were designed to be equivalent to 10 years of natural ageing. • The long-term thermal conductivity and mould susceptibility of the mortars are assessed. • A maximum increase of thermal conductivity up to 30% is obtained after ageing. The use of thermal insulation materials in the opaque walls is one of the best strategies toward the improvement of the thermal performance of the building envelope, thereby contributing to increase the energy efficiency of the built environment. In this context, an increasing number of studies are focusing on the development of mortars with enhanced thermal performance, i.e., thermal insulating mortars. However, considering the innovative character of these materials, reliable data on their long-term performance is still lacking, particularly concerning the thermal performance and suitability to refurbishment works. The aim of this paper is to evaluate the long-term thermal conductivity and biological colonisation of industrially produced and experimentally designed thermal mortars with EPS, cork and silica aerogel aggregates. The long-term performance of the mortars was assessed prior, during and after exposure to three accelerated ageing tests including elevated temperature, freeze–thaw cycles and high humidity levels. For each test, an empirical model (i.e., Arrhenius law, Peck model, and Coffin-Manson equation) was used to compute the acceleration factor, thus allowing to correlate the accelerated and natural ageing results and to estimate the degradation levels that would be obtained after 10 years of exposure to natural weather conditions. The results of the thermal conductivity show that a maximum increase of 10 % and 30 % can be obtained after ageing for the industrially produced and experimentally designed mortars, respectively. Moreover, all mortars were susceptible to mould growth, with the greatest biological colonisation levels obtained after the high moisture content ageing for the experimentally designed mortars. [ABSTRACT FROM AUTHOR]

Older cancer survivors may experience ageing at an accelerated rate when compared to their similar-aged, cancer-free counterparts. Ageing is undoubtedly a significant risk factor for cancer. There is evidence to suggest, however, that this relationship may in fact be bidirectional, with cancer and its treatments contributing to the ageing process. In this review, we outline the current literature linking cancer and anti-cancer therapy to adverse ageing outcomes and explore what additional research is needed in order to conclusively define cancer and its treatment as an accelerator of ageing. [ABSTRACT FROM AUTHOR]

• Export of degradation data for DSSCs under various accelerated ageing conditions. • Discussion of the DSSCs degradation mechanisms for each type of accelerated ageing. • Demonstration of one-diode model as a powerful tool for routine analysis of DSSCs. • Proposal of a predictive model for DSSCs degradation under accelerated ageing. • Accurate prediction of the degradation of DSSCs for all types of accelerated ageing. The present paper constitutes one of the few comprehensive studies found in literature on the stability of dye-sensitized solar cells (DSSCs) under different accelerated ageing conditions. Specifically, the accelerated ageing tests involved isothermal ageing at high or low temperature, thermal shock cycling, hydrothermal ageing, and reverse biasing of conventional DSSCs, fabricated using mainly commercially available materials, prepared for DSSCs application. One-diode model was in all cases applied to the characteristic curve of the solar cells, as a simplified version of the general transmission line model used in electrochemical impedance spectroscopy, for the fast and straightforward analysis of the charge transport and back-reaction kinetics in the DSSCs. A semi-analytical model (residual property model (RPM)) that was previously developed by the last author, was also applied, for the first time to solar cells, to predict the degradation of DSSCs performance due to their accelerated ageing. The results showed that moisture, in combination with high temperature, is the most critical environmental factor that leads to the degradation of DSSCs performance. In all cases of accelerated ageing, the stability of the solar cells seemed to be highly dependent on degradation/desorption phenomena of the conventional hydrophilic ruthenium (N719) dye from the TiO 2 anode. Finally, it is worth mentioning that the RPM accurately predicted the degradation of DSSCs performance in all cases of accelerated ageing. The present paper reveals a simple but powerful approach for routine evaluation and prediction of the stability of DSSCs and, hopefully, of other solar cell technologies under various accelerated ageing conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Primitivo toasted vine-shoots chips were tested as an alternative to oak chips. • Primitivo toasted vine-shoots chips and ultrasound treatment were used during wine aging. • Vine-shoots chips and ultrasound treatment promoted the colour stabilisation, accelerating the aging process of wine. • Primitivo wine enriched of compounds associated with new wood-related aromas. Ageing wine in barrels is an historical practice used to improve the aromatic complexity of wine, but due to the high cost and the long ageing period, alternative approaches have been developed, such as the use of wood chips and ultrasound treatment. The present paper reports the results of an investigation performed on wine (cv. Primitivo). Three treatments were investigated: a) control wine untreated; b) wine with toasted vine-shoot chips (10 g/L); c) wine with toasted vine-shoot chips (10 g/L) and treated by ultrasound. Wines were analysed after 7, 14, 21, and 28 days. The application of ultrasound combined with vine-shoot chips promoted tannin evolution, thereby accelerating the ageing process of wine. The chips addition decreased the total anthocyanins content and increased the stilbenes (trans -resveratrol and trans -piceid) and wood-related aromas (i.e., furfural, 5-methylfurfural) concentration. Finally, wines added with chips were richer in woody, vanilla, oak, and chocolate notes and more preferred by the tasters. [ABSTRACT FROM AUTHOR]

• Acceleration of post-LOCA is adequate if meeting certain conditions. • Multi-scale approach using non-destructive electrical measurements during post-LOCA. • Comparison of different non-destructive diagnostic techniques. Cables important to safety used in nuclear power plants are required to withstand environmental, operational and system conditions to which they are exposed during their design life. This may include harsh conditions resulting from a design basis event (DBE), such as a Loss-of-Coolant Accident (LOCA). The testing procedure includes accelerated thermal and ionizing radiation ageing which brings the tested samples to their end-of-life condition. Accelerated pre-ageing is then followed by accident simulation (LOCA test). The latter part of accident simulation (post-LOCA), which may take up to 1 year, is commonly accelerated based on the Arrhenius approach, however the adequacy of this approach remains a topic of ongoing discussion, lacking a clear scientific or engineering consensus. While numerous works have focused on testing various conditions during accidental and post-accidental conditions in nuclear power plants, there is notable absence of direct assessment of acceleration effects. The aim of this work was to assess the effects of accelerating post-accident conditions on electrical cables using non-destructive electrical measurements. The cables were subjected to thermal and radiation pre-ageing, LOCA test, and then were divided into two groups for post-LOCA tests: one group was tested for one year in non-accelerated post-accident conditions, while the other was accelerated using the Arrhenius approach. Diagnostic methods, including insulation resistance, capacitance, voltage withstand tests, and high-frequency parameters such as attenuation, characteristic impedance, and relative permittivity, were employed for comparing sample conditions. Results from both accelerated and non-accelerated post-LOCA simulations were consistent, indicating that the acceleration was adequate. [ABSTRACT FROM AUTHOR]

• Proposal of a methodology for defining heat-cold ageing cycles adapted to climatic zones. • Link between degradation mechanisms and accelerated ageing procedures for multilayer thermal renderings. • The capillary absorption of thermal and finishing mortars determines their interior or exterior application. • Demonstration of the applicability of the durability evaluation methodology through extensive laboratory tests. The increase of the thermal resistance of building envelopes is a result from the growing demand of energy efficiency. Several new materials and systems emerged in recent years as an answer to that growing need. Thermal mortars applied in thermal rendering systems are an example of how the research community and the building industry try to tackle that challenge. A gap in the durability assessment of thermal rendering systems can however be observed. The existing standardization for the durability assessment of mortars does not allow a consistent evaluation of thermal mortars, especially in multilayer systems. As such, the main goal of the present work consists in proposing a durability assessment methodology of thermal mortars applied as multilayer systems. Accelerated ageing cycles, directly applicable to thermal mortars, were developed through numerical simulation, taking into account material properties, climatic conditions and consequent degradation mechanisms to which the system is subjected. A theoretical methodology for the determination of heat-cold cycles that can represent specific climatic conditions was developed. The implementation of the developed accelerated ageing cycles and the obtained experimental results contributed to the definition of a new durability assessment methodology. This methodology defines the accelerated ageing cycles that should be performed in each climate zone, representative of the main degradation mechanisms. One of the major advantages is the temperature adaption of the accelerated ageing cycles to the climatic conditions. The new methodology contributes to the evaluation of new solutions, during their development stage, and to their adequacy for specific climatic conditions. [ABSTRACT FROM AUTHOR]

Abstract The ageing of beef is essential to provide a tender product which is deemed acceptable by consumers, with beef processors routinely ageing beef for ~ 14 d at 0–2 °C. The rate of tenderisation is directly affected by temperature, and as such the possibility of decreasing the required ageing time by increasing storage temperature could provide an opportunity to decrease associated costs. To test this, 320 beef M. longissimus lumborum portions were subjected to one of 72temperature-time combinations (TTC) incorporating temperatures of 3, 5 or 7 °C and ageing times of 6, 8, 10 or 12 d, with some temperature changes occurring during ageing. Controls (n = 32) were held at ~ 1 °C for 14 d. The application of TTCs did not affect beef quality, however longer storage at higher temperatures resulted in higher microbial loadings. Therefore, it can be concluded that shorter, cooler TTCs could be implemented to decrease ageing time requirements and maintain beef safety. Highlights • Different temperature-time combinations on eating quality and safety were tested. • Higher temperatures and longer ageing time influenced microbial safety. • Temperature-time combinations did not influence colour or quality. • Temperature-time combinations did not influence consumer satisfaction. [ABSTRACT FROM AUTHOR]

Abstract The estimation of the long-term durability of adhesively bonded interfaces between Fiber Reinforced Polymers (FRP) and concrete substrates is crucial because degradation potentiates FRP premature debonding. One of the main reasons for mistrusting the use of FRP composites is the premature debonding phenomenon, which, associated to degradation, has been preventing their widespread use. In this research work, an analytical model is proposed that introduces ageing to estimate the effects of degradation of Glass (G) FRP externally bonded to concrete. Cycles were used to experimentally accelerate ageing of beam specimens, namely, (i) salt fog cycles; (ii) wet-dry cycles with salted water; (iii) temperature cycles between −10 °C and +30 °C; and (iv) temperature cycles between +7.5 °C and +47.5 °C. Based on the experimental results obtained and a corresponding bond-slip curve, the analytical model predicts the complete debonding process between FRP composites and a substrate. Consequently, the temporal evolution of the degradation of the bonded interfaces can be calculated and compared with the initial situation prior to exposure. The effects of the environmental conditions are reported and compared. [ABSTRACT FROM AUTHOR]

Metabolic syndrome (MetS) is a risk factor for the development of diabetes, cardiovascular disease, and all-cause mortality. It has an estimated prevalence of 40 % among older adults. Epigenetic clocks, which measure biological age based on DNA methylation (DNAm) patterns, are a candidate biomarker for ageing. GrimAge is one such clock which is based on levels of DNAm at 100 Cytosine-phosphate-Guanine (CpG) sites. This study hypothesised that those with MetS have 'accelerated ageing' (biological age greater than their chronological age) as indexed by GrimAge. This study examined MetS's association with GrimAge age acceleration (AA) using data from a subsample of 469 participants of the Irish Longitudinal Study on Ageing (TILDA). MetS was defined by National Cholesterol Education Program Third Adult Treatment Panel (ATP III) and International Diabetes Foundation (IDF) criteria, operationalised using the conventional binary cut-off, and as a count variable ranging from 0 to 5, based on the presence of individual components. This study also explored inflammation (as measured by C reactive protein) and metabolic dysfunction (as measured by adiponectin) as possible mediating factors between MetS and GrimAge AA. We found that MetS as defined by IDF criteria was associated with GrimAge AA of 0.63 years. When MetS was treated as a count, each unit increase in MetS score was associated with over 0.3 years GrimAge AA for both ATP III and IDF criteria. Inflammation mediated approximately one third of the association between MetS and GrimAge AA, suggesting that chronic subclinical inflammation observed in MetS has a relationship with DNAm changes consistent with a faster pace of ageing. Metabolic dysfunction mediated the association between MetS and GrimAge AA to a lesser extent (16 %). These data suggest that chronic subclinical inflammation observed in MetS has a relationship with DNAm changes consistent with a greater pace of ageing. • Metabolic syndrome associates with accelerated ageing as indexed by GrimAge. • Inflammation mediated approximately one third of the association. • Metabolic dysfunction mediated 16 % of the association. [ABSTRACT FROM AUTHOR]

Understanding and predicting the storage stability of sweetcorn seeds is critical for effective supply chain management, however, prediction ability relies heavily on accelerated ageing (AA) studies and this is not always directly applicable to natural ageing (NA). In this study, hyperspectral imaging (HSI) and non-targeted metabolomics (LC-MS/MS) were integrated using PLS-R, SVM-R and OPLS-DA to predict loss of seed vigour in NA seeds, using data based on AA seeds. The inconsistencies in the pattern of spectral variation between seeds undergoing AA and NA were first identified. AA-based vigour prediction models were then built using all wavelengths and effective wavelengths (EWs) selected by regression coefficients. These models were externally validated by independent AA and NA seed datasets, respectively. The results yielded satisfactory predictions for AA seeds (R2 ≥ 0.814), but low precision for NA seeds (R2 ≤ 0.696). Metabolome analysis identified 54 differential metabolites, containing a large proportion of amino acids, dipeptides and their derivatives, which were important substances reflecting discrepancies between the ageing mechanisms of AA and NA seeds. Subsequently, N-H bond-related wavebands were deemed to be a possible interference factor in the models' practicability. After removing the N-H bond-related EWs, the AA-based models achieved better performance on NA seeds, with R2 v-2 value increasing from 0.696 to 0.720 for Lvsechaoren and from 0.668 to 0.727 for Zhongtian 300. In summary, coupling HSI, LC-MS/MS and machine learning was shown as an appropriate approach for non-destructive monitoring and predicting the vigour of stored sweetcorn seeds. [Display omitted] • Optimizing seed storability prediction with HSI, LC-MS/MS, and machine learning. • Metabolic differences between seeds undergoing NA and AA emerged. • AA-based PLS-R and SVM-R models differed in predicting vigour of NA and AA seeds. • N–H bond-related EWs may interfere with RC-PLS-R predictive models on NA seeds. • The RC-PLS-R models' applicability was optimized after deleting interference EWs. [ABSTRACT FROM AUTHOR]

The use of antireflective coatings to increase the transmittance of the cover glass is a central aspect of achieving high efficiencies for solar collectors and photovoltaics alike. Considering an expected lifetime of 20–30 years for solar energy installations, the durability of the antireflective surfaces is essential. Here, a novel antireflective SiO 2 coating with a hexagonally ordered closed pore structure, produced with an aerosol-based sol-gel method is benchmarked against two commercial coatings; produced with acid etching and sol-gel roll coating. The optical and mechanical properties together with contact angle characteristics were evaluated before and after various durability tests, including climate chamber tests, outdoor exposure, and abrasion. Compared to the commercial antireflective coatings with open pore structures, the novel coating performed in parity, or better, in all tests. Based on the results of humidity freeze and industrial climate chamber tests, it appears that the coating with closed pore structure has a better ability to prevent water adsorption. Additionally, the closed pore structure of the coating seems to minimize the accumulation of dirt and deposits. The abrasion and cleanability test further confirm the advantages of a closed pore structure, showcasing the coating's mechanical durability. While the coatings exhibit similar hardness and reduced elastic modulus, the closed pore coating proves to be even harder after undergoing the industrial climate chamber test, but also slightly more brittle, as indicated by the probability of crack initiation. In summary the closed pore structure is well suited for tempered and arid climates, making it a truly competitive alternative to existing antireflective coatings. [Display omitted] • Durability of antireflective silica coating for solar thermal applications. • Comparative benchmark tests between coatings with closed- and open pores. • A superior resistance to abrasion, dry soiling, humidity, and temperature is attributed to the closed pore structure. • The antireflective coating with a closed pore structure is well suited for arid and tempered climates. [ABSTRACT FROM AUTHOR]

Highlights • Neuroprogression/neurosenescence paradigm is a less researched component in schizophrenia. • Telomere length is a biomarker of cellular senescence, which is reportedly shortened in schizophrenia. • Neuroimaging studies have demonstrated a significant hippocampal atrophy in schizophrenia compared to other brain structures. • Schizophrenia patients showed a significant sex-by-telomere interaction with both right & left hippocampus. • These cross-sectional observations suggest the need for longitudinal studies to understand postulated accelerated ageing processes in schizophrenia. Abstract Accelerated ageing processes are postulated to underlie schizophrenia pathogenesis. This postulate is supported by observations of reduced telomere length in schizophrenia patients. Hippocampus, one of the most important brain regions implicated in schizophrenia, is shown to atrophy at a faster rate in aging. In this study, telomere length (TL) was measured in 30 antipsychotic-naive/free schizophrenia patients and 60 healthy controls using quantitative PCR assay. Hippocampus volume was measured using voxel-based morphometry. Schizophrenia was associated with differential TL between sexes [Status × Sex; F (1,85) = 5.9, p = 0.017, η2 = 0.065]. Male schizophrenia patients had significantly lower relative TL than female patients [ F (1,85) = 7.38, p = 0.008], while such sex difference was not observed in healthy controls [ F (1,85) = 0.16, p = 0.69]. Schizophrenia patients showed a significant sex-by-telomere interaction with both right & left hippocampus, with male patients showing positive association of telomere length with volume, while female patients showed negative association. Telomere shortening and the positive association of telomere length with hippocampus volume was observed only in male patients with schizophrenia. Since correlational observations in this cross-sectional study does not necessarily support definitive causal relationship, further longitudinal studies examining hippocampus volume and telomere in schizophrenia patients are needed. [ABSTRACT FROM AUTHOR]

Highlights • Accelerated ageing test on SWSSC beams were conducted. • The contribution of BFRP stirrups to shear resistance decreased after conditioned. • An approximately strength retention of 49.4% was observed for SFCB after 9 months. • The cracks became sparse and the load fluctuation became serious after conditioned. Abstract Fibre-reinforced polymer (FRP) bars and seawater sea-sand concrete (SWSSC) is a very promising new combination. When seawater and sea sand are used, not only the tensile reinforcements but also the stirrups and top reinforcements should be FRP to avoid corrosion. In this paper, an accelerated ageing test was conducted on SWSSC beams completely reinforced with FRP bars in the marine environment. Two types of beams were tested. One had a basalt FRP (BFRP) bar as the tensile reinforcement, and the other had a steel-FRP composite bar (SFCB) as the tensile reinforcement. The stirrups and top reinforcements were all BFRP bars. The experimental results indicated that cracks in both types of beams after bending tests became sparse after environmental exposure. The load fluctuation during crack formation increases for environmentally conditioned SWSSC beams reinforced with BFRP bars. After immersion in 50 °C seawater for longer than 6 months, the failure mode of BFRP beams changed from concrete crushing to shear failure, and the contribution of BFRP stirrups to shear resistance capacity clearly decreased. For the SFCB beam, the failure mode changed from concrete crushing to SFCB rupture due to the reduction of tensile strength of SFCB after exposure, which causes a maximum of 11% reduction in load capacity. [ABSTRACT FROM AUTHOR]

Abstracts A soil washing residue (SWR) (containing 90% clay, cadmium (Cd2+) of 132 mg/kg, lead (Pb2+) of 3410 mg/kg) was stabilized with MgO (M) and MgO + bioapatite (MB) respectively at a dosage of 5% in w/w. The stability of the metals in original and amended SWRs was assessed after immediate treatment and using a laboratory accelerated ageing method simulating 26, 52, 78 and 104 years in field conditions. The dissolved Cd2+ and Pb2+ from the SWR in Toxicity Characteristic Leaching Procedure (TCLP) leachates significantly reduced (by 96.84–99.06%) by both amendments after immediate treatment. The stabilization remained effective within simulated 26 years as the TCLP leached Cd2+ and Pb2+ kept below regulatory levels. This immobilization was mainly due to the increased non-bioavailable Cd2+ and Pb2+ from sequential extraction tests in SWR by the amendments. At simulated 52 years, the TCLP leached Cd2+ from M and MB exceeded regulatory level by 106% and 1% respectively. Large amounts of Cd2+ and Pb2+ were leached out by 36.74–48.18% regardless of the treatments at simulated 104 years. Although bioapatite can significantly aid the stabilization of metals by MgO, the stabilization effectiveness for both treatments diminished at simulated 52 years and from 52 to 104 years. Graphical abstract Unlabelled Image Highlights • TCLP leached Cd2+ and Pb2+ reduced by 96.84–99.06% after immediate treatment. • Cd2+ and Pb2+ stabilization remained effective within simulated 26 years. • Effective stabilization owed to increased non-bioavailable metals. • Bioapatite can significantly aid MgO in Cd2+ and Pb2+ stabilization. • Stabilization effectiveness diminished at simulated 52 years and later. [ABSTRACT FROM AUTHOR]

Highlights • Development of an accelerated test for chemically-active antifouling coatings. • Ageing mechanism based on the coating erosion and the formation of a leached layer coming from the release of biocides. • Correlation between in vitro and in situ ageing of two coatings. Abstract The accelerated ageing of chemically-active antifouling coatings was investigated by performing in vitro and in situ static/dynamic cycles. One of the main objectives of this study was to develop an ageing test able to predict long-term antifouling coating performances in less than one year with a mechanism which is representative to the natural ageing. One self-polishing copolymer (SPC)-based coating and one controlled depletion polymer (CDP)-based coating were selected because of their well-known distinct mechanisms of action. Five static artificial conditions were used in cycles and their influence on the ageing of two coatings was investigated. Comparison of two key parameters such as erosion of the coatings and formation of a leached layer or a depleted layer at the surface of the two coatings were investigated in accelerated and in situ tests. Results support the different mode of action of the two coatings. The static artificial conditions were shown to affect the residual antifouling efficiency differently. Deionized water buffered at pH = 8 with tris(hydroxymethyl)methylamine was the only static artificial condition that led to an acceleration of both the formation of a leached layer or a depleted layer at the surface of the two coatings and their erosion. [ABSTRACT FROM AUTHOR]

Highlights • New and accelerated aged parchments and leathers were naturally aged for 4 years. • The effect of natural ageing was assessed by the denaturation temperature T d. • For parchments the largest decrease of T d was observed for the new samples. • For the strongly accelerated aged parchments the temperature shift was negligible. • For leathers the shift of T d was unrelated to the previous accelerated ageing time. Abstract The paper discusses the effects of a 4-year natural ageing on hydrothermal stability of new and previously accelerated aged parchments and leathers. It was observed that natural ageing generally lowers the denaturation temperature (measured using DSC), but in a different way for the two types of these collagen-based materials. Thus, for parchments the largest effect (up to 7 °C) was observed for the new samples, while for the strongly aged ones the temperature shift was negligible. For leathers, no relevant dependence of the denaturation temperature shift (3.0 ± 1.0 °C in average) with the previous accelerated ageing time was observed. For parchment, the enthalpy of denaturation decreases substantially following natural ageing, while for leathers no significant alteration was observed. It was also found that the 1-day accelerated ageing performed in 2013 had comparable effects on the denaturation temperature of these materials as the 4-year natural ageing, making the possibility of predicting the effects of natural ageing on patrimonial artifacts manufactured from parchment and leather. [ABSTRACT FROM AUTHOR]

Highlights • The effect of combined ageing on the residual stability of EVA was quantified. • Residual stabilities decrease exponentially with increasing radiation dose. • Thermal ageing at 90 °C reduces stability less than the radiation ageing. Abstract Effect of gamma radiation and temperature on the stability of ethylene vinyl-acetate copolymer (EVA) cable insulation was studied by non-isothermal DSC measurements. From the dependences of oxidation onset temperatures on heating rates, the kinetic parameters describing the temperature dependence of induction period have been obtained. The kinetic parameters enabled to calculate the length of induction period for a chosen temperature and to evaluate the residual stability of EVA cable insulation after an artificial ageing stress. It has been shown that the extinction of residual stability with radiation dose obeys a first-order kinetics for all studied temperatures and the extinction constants of residual stabilities have been calculated. Their values indicate, that the radiation ageing has a more significant effect on the residual stability of EVA cable insulation than the temperature ageing at 90 °C. [ABSTRACT FROM AUTHOR]

The degradation of fluorinated polyurethane (FPU) coating on AA7075 Al-alloy was studied by electrochemical impedance spectroscopy (EIS) through accelerated ageing tests under ultraviolet A (UVA) irradiation and salt spray tests (SST), respectively. The morphological changes of the coating were observed by scanning electron microscope (SEM) and atomic force microscopy (AFM). Furthermore, the variation of thermal performance and functional groups of the FPU coating were characterized by differential scanning calorimeter (DSC), thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FTIR). EIS results showed that SST caused faster decrease of corrosion barrier than the UVA irradiation, especially in the initial stage. Nevertheless, the UVA rather than the SST increased the glass transition temperature ( T g ) and the brittleness of FPU coating, indicating that the UVA could accelerate the chemical degradation of FPU coating. In addition, many blisters and wrinkles could be found on the surface of FPU coating during UVA but only micropores could be found during SST. These micro flaws provide fast channels for aggressive ions to migrate to the coating/ metal interface, accelerating the delamination of FPU coating and the Al matrix. [ABSTRACT FROM AUTHOR]

Abstract Technical lifetime prediction of polymeric materials is often based on accelerated ageing tests at elevated temperatures. Samples are exposed to relatively high temperatures to accelerate the natural degradation processes. For district heating pipes, accelerated thermal ageing is the ordinary method used to determine the lifetime of pipes. According to the Standard EN 253:2009 + A1:2013, the district heating pipes shall be subjected to an accelerated thermal ageing for a long period of time at 160 ˚C or 170 ˚C. The lifetime is determined by extrapolation using the Arrhenius relationship. However, papers published recently have questioned this method, especially the high temperatures used for ageing of the pipes and the use of Arrhenius equation to describe the complicated degradation mechanisms, which can result in the erroneous estimation of the technical lifetime. Our investigation has shown the complexity of the pipe’s degradation mechanisms. The behaviour of mechanical shear strength at elevated temperatures (T > 130 °C), suggests an alteration rather than an acceleration of the degradation mechanisms. Accelerated ageing tests should reproduce the proper natural ageing mechanisms. The analyses of PUR’s thermal conductivity and its chemical structure by FTIR confirmed the degradation patterns. [ABSTRACT FROM AUTHOR]

The lifetime of pre-insulated district heating pipes (DHPs) is commonly evaluated using the method described in the normative European Standard EN 253. This lifetime is normally calculated using an Arrhenius equation, which makes use of test results from accelerated ageing tests at elevated temperatures. In this investigation, long-term accelerated ageing tests of DHPs at elevated temperatures were carried out. The ageing behaviour, especially at the interface between steel pipe and polyurethane (PUR) foam, showed several routes of degradation. It is clearly demonstrated using measurements of shear strength, thermal conductivity and alterations of chemical structure by Fourier Transform Infrared spectroscopy that the results of accelerated ageing at 170 and 150 °C significantly diverge from those obtained from the ageing test at 130 °C. It is therefore concluded that accelerated ageing at commonly used high temperatures does not create an acceleration of degradation processes at the steel/PUR interface relevant for the DHP application, but rather a significant alteration in mechanism. This finding is of crucial importance for the use of EN 253 and the development of future methods for lifetime prediction of DHPs. [ABSTRACT FROM AUTHOR]

Soil washing residue (SWR), which typically concentrates the washed toxic metals and is comprised of high contents of clay particles, may pose risks to the surrounding environment. This study aims to simulate accelerated ageing to assess the stability of selected metals (Cd 2 + (132 mg/kg), Cu 2 + (248 mg/kg) and Pb 2 + (3470 mg/kg)) in a SWR (89.68% of clay) with and without biochar treatment. The soil was incubated under constant moisture and wet-dry cycles (accelerated ageing), respectively, and the mobility and fractions of heavy metals in the soils with and without biochar treatment were examined. Under the constant moisture condition, biochar addition at 5% w/w reduced the leached Cd 2 + (by 1.81%) and Cu 2 + (by 8.70%) from SWR at day 1 and the leached Cu 2 + (by 51.08%) and Pb 2 + (by 25.36%) from SWR at day 14; however, the leached metals in the TCLP solution from the biochar-amended soils still exceed the regulatory limits (1 mg/L for Cd 2 + , 5 mg/L for Pb 2 + , no regulatory limits for Cu 2 + ). Conversely, accelerated ageing (14 days) significantly increased the fractions of exchangeable Cd 2 + (from 3.63–3.94% to 6.21–6.29%) and Pb 2 + (from 0.025–0.027% to 0.034–0.041%) as well as the TCLP leachabilities of Cd 2 + (from 2.91–3.28% to 3.46–3.73%), Cu 2 + (from 0.08–0.10% to 0.03–0.06%) and Pb 2 + (from 0.25–0.35% to 0.52–0.57%) in the soils, as compared with those incubated under constant moisture, regardless of biochar addition. This study reveals challenges associated with stabilising SWR due to the presence of residual fine-grained particles. [ABSTRACT FROM AUTHOR]

In the building sector, various adhesive materials are experiencing an increased usage for sealing of overlaps and joints between most commonly used building materials, around penetrations, pipes and windows for increasing the moisture tightness and the airtightness of buildings. Among the adhesive materials are adhesive tapes that are used to ensure adequate airtightness of a building and thus must be able to withstand severe environmental conditions without significant long-term deterioration. Durability test methods are needed to evaluate whether the tapes fulfill their performance requirements for the service life of the whole building. However, there is a lack of reliable test methods and evaluation procedures for tapes used for building applications. This study was performed to evaluate tape durability testing and evaluation methods, which hence form a basis for further improvements of the existing methods. [ABSTRACT FROM AUTHOR]

The degradation behaviors of hemp fibers reinforced PP biocomposites under outdoor and artificial weathering were compared to establish a correlation. For this purpose, several measurements were performed throughout the expositions. Mechanical performance was tested by three-point bending test. Microstructure and chemical composition changes were also assessed. Otherwise, visual aspect and topography were determined. The artificial weathering effectively accelerated the degradation mechanisms. Oxidation pathways and surface aspect alteration of both polymer and biocomposites occurred faster. However, whereas biocomposites were mainly subjected to outdoor conditions due to high sensitivity of hemp fibers, neat PP was globally mostly affected by laboratory chamber conditions. Its oxidation rate largely outstripped reinforced materials ones. Principal Component Analysis was used for verifying the differences of variables correlations profiles between artificial and exterior ageing dataset in order to compare the degradation mechanisms. Through the statistical analysis, some attempts were made to find equivalence between artificial and outdoor weathering times thanks to properties degradation rate similarities. [ABSTRACT FROM AUTHOR]

A natural antioxidant, quercetin, was adsorbed on the surface of halloysite nanotubes in various amounts to prepare a controlled release device. The combined additive was added to polyethylene providing antioxidant levels of 250, 500, 750 and 1000 ppm. All polymer samples contained 1000 ppm Sandostab PEPQ phosphonite secondary antioxidant as well. The stabilizing efficiency of quercetin was determined in processing experiments and by accelerated ageing. Quercetin proved to be a very efficient stabilizer of polyethylene. The use of the halloysite nanotube support resulted in more homogeneous dispersion and facilitated the dissolution of the compound in the polymer. Because of the high energy of halloysite surface, the stabilizer adhered to it very strongly and did not dissolve in polyethylene below a critical concentration. The melt stabilization efficiency of quercetin did not decrease in the presence of the halloysite support. The efficiency of long term stabilization decreased somewhat, but halloysite nanotubes pretreated with the stabilizer possessed a controlled release function, ageing was slower in their presence than with separately dispersed components or in the absence of the halloysite. [ABSTRACT FROM AUTHOR]

Low dropout voltage regulators (LDOs) play a crucial role in power management circuits. Unfortunately, long-term instability may threaten their functionality as well as their EMC performance, both concerning immunity and emission. The modeling of EMC deviations due to ageing degradation can assist to estimate the life expectancy of the LDOs and improve the reliability of the circuits. In this paper, a novel model is proposed to predict the conducted immunity deviations of LDOs based on convolutional neural networks and a long short-term memory (CNN LSTM) algorithm. It can explicitly learn the features of the conducted immunity in a wide frequency range and can accommodate multiple stresses which are applied to mimic the ageing process. The model is validated by carrying out an experiment where the DC (direct current) characteristics and conducted immunity performance are consistently monitored when the LDOs are subject to thermal-electrical-stresses in an ageing test. It can provide accurate immunity predictions and bypass the internal structure of the chips. It is shown that the proposed approach outperforms other models. • A novel model is developed to predict the conducted immunity deviations of LDO regulators based on CNN and LSTM. • The DC characteristics EMC deviations of LDO regulators are carried out by multi-stresses accelerated ageing test. • The proposed model can explicitly learn the features of the LDOs' conducted immunity performance in a wide frequency range and can accommodate multiple stresses. • The model can provide accurate immunity predictions and bypass the internal structure of the chips. [ABSTRACT FROM AUTHOR]

Self-made and commercial acrylic paints containing phthalo blues (C. I. Name PB15:1, PB15:3, PB15:6, and PB16), and phthalo greens (PG7 and PG36) were exposed to artificial ageing in a Xenon Arc simulator (910 W/m 2 ). The ageing conditions are reproducing the typical outdoor solar radiation, which artworks conceived for outdoor spaces might be exposed to. Complementary analytical techniques were employed in order to study the photodegradation process occurring on the paints. By means of micro-Raman spectroscopy the pigment component in the paints was investigated, while Py-GC/MS in double shot mode was employed for the characterization of photodegradation products of both binder and pigments. Furthermore, FTIR-ATR analyses allowed semi-quantitative considerations about the influence of each selected pigment on the degradation of the acrylic binder. Finally, UV-Vis spectroscopy allowed the discrimination of the pigments in the paints and the study of the colour changes. Raman spectra acquired on both, unaged and aged specimens did not show any difference concerning the pigment bands, whereas Py-GC/MS in double shot mode, revealed a decrease in the thermal stability of the pigments as well as of the acrylic binders identified (nBA/MMA, EA/MMA, nBA/Sty/2-EHA, and 2-EHA/MMA). Typical photooxidation products of acrylic binders, such as increased monomers and oligomers, related to side-chain scission as well as main-chain scission reactions, were characterized by means of Py-GC/MS and FTIR-ATR. Commercial paints revealed also whitening and chalking phenomena, mainly due to the presence of white fillers and additives in the paints formulations. These phenomena could be registered also by UV-Vis spectroscopy. [ABSTRACT FROM AUTHOR]

One major problem with ball and socket artificial discs is the migration of wear particles to the surrounding tissues. This debris can cause inflammation that can lead to implant loosening. Encapsulating the artificial disc with an elastomer sheath could prevent this problem by retaining the wear particles within the disc. The encapsulation sheath will face millions of tensile cycles during the implant life and, therefore, it must have the ability to withstand large strains without fracture. Using cyclic displacement, crack nucleation was applied on dumbbell specimens and crack growth was applied on rectangular specimens with an initial crack. Both tests were performed on Silex silicone and polyurethane ether elastomer specimens, both with a Shore durometer hardness of 40 shore A. No samples completely failed during the crack nucleation tests after five million cycles. The polyurethane ether elastomer showed a slower rate of crack growth life (421 k cycles to reach 70 mm crack length) than silicone elastomer (221 k cycles to reach the same crack length) in the control group. Accelerated ageing decreased the hardness and the crack growth rate of the polyurethane elastomer but had the opposite effect for the silicone elastomer. Gamma sterilization increased the crack growth rate and did not affect the hardness of the polyurethane elastomer. The hardness and the crack growth rate of the silicone elastomer were increased after gamma sterilization. [ABSTRACT FROM AUTHOR]

Accelerated aging experimental investigations are performed on polymeric insulators which are used for extra high voltage (EHV) and ultra high voltage (UHV) transmission. A newly developed rotating wheel and dip test facility as per std. IEC 62217 is used for the study. The experimental study is conducted with AC stress for 15000 cycles. The specimen insulators used are of 725 mm creepage and treated under different environmental stresses close to the real service life. The present study focuses on the effect of acidic environment during acid rain encountered by the polymeric insulators. The contaminants used for the study are as per standard and practically observed acid rain information. A comparative study is carried out for normal and acidic environmental conditions, some interesting results are observed. Leakage current monitoring and visual observation were conducted at regular intervals. Results show acid treatment is found to be comparatively more severe than the normal treatment. Further Physico-chemical investigation are carried out using Fourier Transform Infrared (FTIR) Spectroscopy and Scanning Electron Microscopy (SEM), Energy dispersive X-ray Analysis (EDAX) and Thermo-Gravimetric Analysis (TGA) which confirm the severity of material degradation of polymeric insulators and corrosion over metal end fittings under acidic environmental condition. [ABSTRACT FROM AUTHOR]

Pre-insulated district beating pipes (DKP) have been in use daring the last fort)* years. Many improvements and development have been done in the system. However, life-time prediction is soil an uncertain issue. This paper is a pan of a bigger project with the objective to determine mechanisms related to the deterioration of the mechanical and insulation properties of pre-insulated heating pipes as a result of ageing. The focus in this project is on degradation mechanisms of the PUR material at high temperatures. In this paper some results of the two types of exposure are presented. The first type comprises a condition where the new pipes are subjected to accelerated ageing at three different temperatures. The second type comprises condition, when the PUR material itself is aged in different atmospheres in order to identify different degradation mechanisms. The chosen ageing temperatures in the first condition were 1309C, (close to the supply temperature), 150°C and 170SC, (accelerated ageing temperature in EN 253 [1]). Changes in thermal insulation and the adhesion force between the PUR and the steel pipe were evaluated using the transient plane source (TPS) technique and the SP plug method respectively. The results of ageing show that the degradation of PUR is a multi-stage process composed of a rapid change in properties followed by a plateau phase which changes later to a gradual deterioration of the properties. The results of die PUR material exposure at 150'C in air and in nitrogen showed significant differences in the degradation characteristics between the two environments as were revealed by DSC and FTTR methods. [ABSTRACT FROM AUTHOR]

In the present research, an industrially aged Pt/Al 2 O 3 catalyst was used as a basis for the study on the sulfur deactivation and the development of more resistant catalytic materials. The catalytic activities of both industrially and laboratory-aged materials in DMDS oxidation were studied in addition to characterization by XRD, XPS, FESEM, TEM and N 2 adsorption. The industrial ageing induced a phase change from γ-Al 2 O 3 towards θ-Al 2 O 3 , formation of aluminum sulfates and an increase in Pt particle size as well as a change in the oxidation state of Pt to a higher state. These changes caused an increase of 30 °C in the light-off temperature for DMDS oxidation. Accelerated ageing in the presence of SO 2 and H 2 O vapor at 400 °C for 5 h decreased the activity of the Pt/Al 2 O 3 at the same level than for the industrially aged catalyst even though smaller sulfur content and no sintering of γ-Al 2 O 3 were observed. Pt sintering (10–20 nm) in both cases was observed. The XPS results confirmed the formation of new sulfate phases and the interaction between sulfur and the active phase as well as the support of the catalyst undergone accelerated ageing. After the accelerated ageing of copper-based catalysts, the 0.3Pt10Cu/Al 2 O 3 ǀ 0.8 SiO 2 ǀ 0.2 catalyst showed an interesting resistance towards sulfur deactivation, as it was expected. [ABSTRACT FROM AUTHOR]

This research aims at determining the fracture envelope of an adhesive as a function of the water content. The fracture toughness of an adhesive joint was determined under pure mode I, II and mixed mode I + II loadings, in three different environments: dry, aged in salt water and aged in distilled water. The fracture toughness under mode I and II were determined using Double Cantilever Beam (DCB) and End-Notched Flexure (ENF) tests, respectively. The characterization of the fracture toughness under mixed-mode was done using an apparatus capable of applying a wide range of loadings that go from pure mode I to almost pure mode II. To accelerate the diffusion process and obtain a uniform water concentration in the adhesive joint, a modified DCB specimen (ODCB specimen) was adopted. Finite Element (FE) analysis was used to determine the gradient of water concentration in both specimens and to validate the use of the modified DCB specimens, comparing the fracture toughness obtained using DCB and ODCB specimens. It was found that the toughness of the adhesive changed as a function of the ageing environment. For the salt water environment, the mechanical properties increased, while for the distilled water environment, degradation of the mechanical properties was observed. [ABSTRACT FROM AUTHOR]

Photocatalytic building materials have been shown to be a promising remediation technique for air pollutants such as NOx and VOC's. However, there are still doubts and questions about the durability of the air cleaning characteristic in time. In this respect, a pre-normative research is being undertaken at BRRC as a first step towards evaluation of the life time of these photo-active air purifying products. This is done by combining and adapting existing durability tests for cement-based materials with standardized test methods to determine the photocatalytic activity. First results of this research are presented here, including a state-of-the-art on accelerated ageing testing as well as the validation of applicable ageing procedures in combination with a normalized evaluation test for photocatalytic NOx abatement. Finally, recommendations for future work regarding durability testing on photocatalytic building materials are also given. [ABSTRACT FROM AUTHOR]

The urgent need for revision of the normative test method (EN 253) for the lifetime prediction of district heating pipes requires a better understanding of the failure mechanisms involved. Therefore, various methods were used to study thermal degradation characteristics of rigid polyurethane (PUR) foam in both air and nitrogen atmosphere. Accelerated ageing in nitrogen caused insignificant changes, whereas ageing in air caused significant changes in weight, dimensions, chemical structure and cell gas composition, indicating importance of the thermo-oxidative type of degradation. A clear indication of the thermo-oxidative type of degradation was the formation of new carbonyl groups in PUR together with the loss of CH 2 groups after ageing in air. Another result of ageing in air was the loss of pentane and cyclopentane, and the formation of some new volatile compounds in the cells of PUR foam. However, despite a large difference in degradation characteristics between the samples aged in air and in nitrogen, no significant difference in the flexural strength of PUR foam was recorded during the induction stage of the degradation process. Furthermore, it is shown that the significant drop in shear strength, which reflects the adhesion force between PUR foam and steel pipe, observed during the early stage of accelerated ageing of district heating pipes is not caused by thermo-oxidative degradation. [ABSTRACT FROM AUTHOR]

Metals are mostly painted to improve corrosion protection of the coated item. Nevertheless, paints can be used to deliver visual aspects to them. Several investigations were conducted to comprehend color variation of paints as function of accelerated tests however, limited information is found concerning these variations versus field exposure. Thus, there is the interest to cover this lack of information and investigate color changes of waterborne paints versus field exposure. In this study colored styrene-acrylic painted steel panels were naturally aged in the alpine climate of Trento, northern of Italy. Color measurements were conducted according to the CIEL*a*b* standard. Gloss measurements and FT-IR spectroscopy assessed variations on the surface topography and chemical structure of the coated panels. It was observed that the changes in color of the colored paints were commanded by the interaction of ultraviolet radiation and they were dependent on the chemical nature of the color pigments. In addition, in the months with attenuated solar irradiance and predominance of TOW ISO conditions, gloss reduction rates and L* of the coated panels have their evolution trend shifted. Upon accelerated UV.B ageing conducted in dry condition neither fluctuations on the L* nor attenuation on the gloss reduction rates were detected. [ABSTRACT FROM AUTHOR]

In order to investigate a synergetic role of water and oxygen in the degradation of permanent paper in archiving climate, accelerated ageing in three different conditions was conducted: humid air, humid nitrogen and dry air. This allowed to decouple acid-catalysed hydrolysis versus oxidation of cellulose. After ensuring the reliability of the ageing experiment, the degradation state of the paper was assessed. Various techniques (size exclusion chromatography, pH extraction, alkaline reserve, paper colour and water content) were used. It appeared that the cellulose scission rate of the Canson® permanent paper was reduced compared to the Whatman No. 40 acidic cotton paper used as reference, but not in the same proportion for all the ageing conditions. This was attributed to a lower acidification, inhibiting acid-catalysed hydrolysis, due to the presence of the alkaline reserve. The degradation mechanisms are the same for both papers, which exhibited a similar chemical and physical degradation. [Display omitted] [ABSTRACT FROM AUTHOR]

• Accelerated weathering of the Highly modified Asphalt (HiMA). • Solvent extraction and recovery of the RAP and HiMA. • FTIR analysis of the aged HiMA and aged VG-30. • Benzene and toluene as solvents used to extract asphalt binders. A growing market for Highly Modified Asphalt (HiMA) has led to the development of HiMA based Reclaimed Asphalt Pavement (RAP) (i.e., aged HiMA). In order to understand the aged HiMA physical and chemical properties, the aged HiMA must be extracted. Usually, the aged binder is extracted using a solvent extraction process. During the extraction process, the aged binder may change its properties, therefore, it is important to evaluate the same. Accordingly, the Fourier Transform Infrared (FTIR) analysis is conducted on three binders namely VG-30, HiMA and RAP to evaluate the changes in the chemical composition due the extraction process. In this research, two solvents i.e., benzene and toluene are used for the extraction of the aged binder. It is confirmed that the extraction process affected the ageing behaviour of the binders. Comparatively, benzene showed high reactivity with the aged binders than the toluene. It is concluded that among three binders, aged HiMA had a significant reaction with the solvent, reduced the cross-linking copolymer and increased the stiffness. The FTIR results indicate that the solvent extracted aged HiMA may show different physical properties. The accelerated weathering of the VG-30 results confirm that the ageing characteristics of the VG-30 are similar to the RAP. It is emphasized to conducted further studies on the accelerated weathering effect on the asphalt to obtain consistency in the test results. It is recommended to analyse the ageing behaviour of HiMA and solvents to achieve consistency in the test results. [ABSTRACT FROM AUTHOR]

Long-term stability is a major issue preventing dye-sensitized solar cells (DSCs) market implementation. The DSC stability problem relates to the sealing methods which usually employ thermoplastic sealants. This communication shows for the first time that laser glass sealing originates stable and efficient DSCs. Laser sealed DSCs showed remarkable stability compared to the Surlyn® sealed devices ( ca . 2% vs . 44%) after accelerated ageing during 1000 h, at 65 °C, light intensity of 765 W m −2 and resistive electrical load (~0.6 V). These results show that efficient encapsulation methods are crucial to DSC stability and that the developed sealing process can bring stable and efficient DSCs to the photovoltaic market. [ABSTRACT FROM AUTHOR]

The objective of this study is to evaluate the effects of third-body particles on the in vitro wear behaviour of three different sets of polyethylene acetabular cups after prolonged testing in a hip simulator and accelerated ageing. Vitamin E-blended, cross-linked polyethylene (XLPE_VE), cross-linked polyethylene (XLPE) and conventional polyethylene (STD_PE) acetabular cups were simulator tested for two million cycles under severe conditions (i.e. by adding third-body particles to the bovine calf serum lubricant). Micro-Fourier Transform Infrared and micro-Raman spectroscopic analyses, differential scanning calorimetry, and crosslink density measurements were used to characterize the samples at a molecular level. The STD_PE cups had twice mass loss than the XLPE_VE components and four times than the XLPE samples; statistically significant differences were found between the mass losses of the three sets of cups. The observed wear trend was justified on the basis of the differences in cross-link density among the samples (XLPE>XLPE_VE>STD_PE). FTIR crystallinity profiles, bulk DSC crystallinity and surface micro-Raman crystallinity seemed to have a similar behaviour upon testing: all of them (as well as the all-trans and ortho-trans contents) revealed the most significant changes in XLPE and XLPE_VE samples. The more severe third-body wear testing conditions determined more noticeable changes in all spectroscopic markers with respect to previous tests. Unexpectedly, traces of bulk oxidation were found in both STD_PE (unirradiated) and XLPE (remelting-stabilized), which were expected to be stable to oxidation; on the contrary, XLPE_VE demonstrated a high oxidative stability in the present, highly demanding conditions. [ABSTRACT FROM AUTHOR]

Pultruded rods of carbon fiber reinforced polymer (CFRP) are excellent alternative materials to steel tendons for the anchoring of deep-sea oil drilling floating platforms. However, the ageing of the rods for use as tension leg in platforms operating in harsh and unusual offshore conditions, and degradation mechanisms associated with these materials should be investigated. In this work, a systematic study was carried out aiming at evaluating how accelerated ageing affects the performance of pultruded CFRP rods, focusing on microstructure, tensile behavior, and thermal and chemical stability. CRFP rods with epoxy and with vinylester resins were evaluated. Rods were aged in hot distilled water, in hot seawater, and in UV radiation wheatherometer camera. Degradation was more severe in the vinyl-ester rods based on tensile strength and stiffness results. Deterioration of the fiber-matrix interface and consequent fiber debonding was the main failure mechanism. The vinyl-ester rods presented higher water uptake than the epoxy rods in both distilled water and seawater, and lower mechanical strength after exposed in the latter. In general, the epoxy resin CFRP rods were more resistant to the ageing processes evaluated. [ABSTRACT FROM AUTHOR]

Unilateral nuclear magnetic resonance (NMR) and imaging thermal microscopy (imageMHT) were performed on newly obtained and artificially aged vegetable tanned leathers. Calf and sheep leathers tanned with vegetal extracts of mimosa bark, quebracho and chestnut wood were compared. Ageing was simulated by exposing the leather samples to heating at 70 °C in controlled atmosphere at 30% relative humidity and irradiating them with 4000 lx in the visible light region for 8, 16, 32 and 64 days. Proton spin-lattice relaxation times T 1 and effective spin-spin relaxation times T 2eff were measured at room temperature and their trend variation compared with the corresponding variations of shrinkage temperature T s and total length of shrinkage interval measured by imageMHT. Newly obtained leather displayed different proton relaxation times and shrinkage temperatures depending on both the collagen origin and tannin type. Effective spin-spin relaxation values shown to be discriminative for collagen origin and sensitive to the cross-linking degree, whereas spin-lattice relaxation values were more sensitive to the tannin type. Both NMR relaxation times were sensitive to the changes in the water dynamics upon ageing due to the formation of collagen damaged intermediate states and shown a sudden change when the tannin matrix was depleted (e.g. de-tanning). [ABSTRACT FROM AUTHOR]

This paper presents the findings of a user study which explored tactile and aesthetic responses to new and artificially aged mobile phone cases made from bamboo, walnut, cork, leather, brushed titanium, plastic and rubber. The paper outlines test methods for accelerated ageing of the external enclosures of consumer electronics based on the types of wear experienced in use, and the use of semantic differential scales (SDS) to probe user attitudes to these materials. The results indicate that preferences for the materials tested were extremely subjective, and even a single participant can have conflicting requirements for the characteristics of the materials (for example, sleek and shiny yet easy to grip). Whilst in general participants preferred the new materials and saw the ageing process as negative, there were examples where the aged samples either scored more highly due to durability (titanium) or received positive comments about the aesthetic changes caused by severe ageing (bamboo and leather). This study captured the participants' immediate, visceral response to the materials, which may be very different to their feelings towards materials and objects that they have owned and interacted with for a period of time. [ABSTRACT FROM AUTHOR]

First-generation (irradiated and remelted or annealed) and second-generation (irradiated and vitamin E blended or doped) highly crosslinked polyethylenes were introduced in the last decade to solve the problems of wear and osteolysis. In this study, the influence of the Vitamin-E addition on crosslinked polyethylene (XLPE_VE) was evaluated by comparing the in vitro wear behavior of crosslinked polyethylene (XLPE) versus Vitamin-E blended polyethylene XLPE and conventional ultra-high molecular weight polyethylene (STD_PE) acetabular cups, after accelerated ageing according to ASTM F2003-02 (70.0±0.1 °C, pure oxygen at 5 bar for 14 days). The test was performed using a hip joint simulator run for two millions cycles, under bovine calf serum as lubricant. Mass loss was found to decrease along the series XLPE_VE>STD_PE>XLPE, although no statistically significant differences were found between the mass losses of the three sets of cups. Micro-Raman spectroscopy was used to investigate at a molecular level the morphology changes induced by wear. The spectroscopic analyses showed that the accelerated ageing determined different wear mechanisms and molecular rearrangements during testing with regards to the changes in both the chain orientation and the distribution of the all-trans sequences within the orthorhombic, amorphous and third phases. The results of the present study showed that the addition of vitamin E was not effective to improve the gravimetric wear of PE after accelerated ageing. However, from a molecular point of view, the XLPE_VE acetabular cups tested after accelerated ageing appeared definitely less damaged than the STD_PE ones and comparable to XLPE samples. [ABSTRACT FROM AUTHOR]

The axial shear strength of plastic jacket pipes consisting of a steel medium pipe surrounded by polyurethane insulation and a casing of polyethylene was determined after service life. Recalculation of the physical life to equivalent life at 120 °C with the respective Arrhenius equation showed the envelope of lifetime ends much earlier than stated as minimum requirement in EN253. A method to determine an apparent activation energy considering additionally the oxidative degradation of PUR in plastic jacket pipes is presented. Enabled gas exchange within accelerated ageing similar to 30 years of life time resulted in an apparent activation energy of 95 kJ/mol, and additionally a further degradation, obviously due to corrosion, was found. [ABSTRACT FROM AUTHOR]

Carbon fibre reinforced polymer (CFRP) sheet has gained its popularity to retrofit civil structures which is bonded externally, typically on the soffit of a beam. In this study, the bond between carbon fibre reinforced polymer (CFRP) and concrete is improved by modifying the property of commercial epoxy and compared against normal epoxy. The deterioration in bond strength was produced by placing the beam into salt water under wet dry cycles. Also, a model is proposed to determine the bond strength from flexural test and compared against the available bond strength models which are typically obtained from pull out test. This proposed model shows promising results in terms of predicting the bond strength from flexural test. In addition, a strength reduction factor is introduced to incorporate the effect of wet dry cycles to predict the long term behaviour. It is found that the modified epoxy enhance the ductile property and bond strength. [ABSTRACT FROM AUTHOR]