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In this paper, based on our previous expertise on ceramic artifacts, several archaeometric methods applied to some samples collected from the Dudești archaeological site (Oltenia region, Romania) are reported for the first time in the literature. The chemical composition, and microstructural and morphological characterization of these samples offer important conclusions about the processing conditions. Some specific techniques such as X-ray diffraction (XRD), wavelength-dispersive X-ray fluorescence (WDXRF), optical microscopy (OM), stereomicroscopy, environmental scanning electron microscopy (ESEM), Fourier-transform infrared spectroscopy (FTIR), and Raman spectroscopy provide compositional information about composition and the decay processes. Additionally, the Brunauer–Emmett–Teller (BET) method helps to estimate pore sizes and specific surface areas. A thermogravimetric analysis (TGA/TDG) was used to establish details regarding the production technology and also the raw materials source used to make the ceramics. The obtained results indicated that the ceramics are based on a paste of muscovite and feldspar, with high plasticity, together with quartz and hematite/goethite and calcite, the latter in very low concentrations. According to the obtained results, we could assume that clays from the investigated samples had a low concentration of calcium. Gypsum is present as paste in a very low concentration, identified by the presence of a sulphate group in WDXRF. In the same context, iron oxides have a significant impact on the firing atmosphere of iron-rich clay, resulting in blackening under reducing conditions and a reddish coloration under oxidative conditions. The use of hematite and gypsum as pigments further contributes to the color variations in the pottery. The consistent firing temperature range of 200–600 °C in Dudești pottery implies a standardized production process, the variation in color being dependent on the specific reducing/oxidative regime conditions (reducing atmosphere followed by rapid oxidation). This relationship between clay composition and local sources suggests a connection to Neolithic pottery production in the region and their color depending on the reducing/oxidative regime conditions.

Paper aging and protection processes play an essential function in the preservation of library collections and archives. In this study, some physical-mechanical properties of paper samples from XXth century books (private collections), such as pH acidity, tensile strength, and modulus of elasticity, as well as optical properties, such as absolute change in yellowness, were examined before and after treating them with hydroxyapatite nanoparticles (HAp). Accelerated light aging was also evaluated and discussed. The treatment with HAp nanoparticles increased the paper’s pH to slightly alkaline values (approximately pH 8). Washing and treating the paper improved its mechanical properties compared to untreated paper; the tear length increased by 35% and the modulus of elasticity increased by 56%. That the treated and aged samples are more elastic than the original samples demonstrates that HAp nanoparticles consolidated the cellulose fibers. Additionally, particle morphology, size, composition and size distribution were assessed via image analysis using scanning electron microscopy (SEM-EDX), atomic force microscopy (AFM), and the ImageJ processing program.

Currently, approximately 70% of paintings in museum collections are affected by the presence of metallic soaps, evidenced by spherical globules visible on the surface of the paintings. They are responsible for altering the paintings’ surface through processes such as exfoliation and cracking, or even in the form of surface “skins” that appear in the pictorial layers. The objective of this study is the investigation of the icon paintings from Saint Mary Monastery, Techirghiol, Romania, which underwent some restoration procedures. This study is so important/significant, due to the presence of efflorescence that is correlated with the conversion of some fatty acids, as palmitic acid, stearic acid and azelaic acid, in the so-called metallic soaps through the reaction of the metals contained in the pigments from the painting layer and the binder. The investigated paintings are strongly affected by zinc carboxylate aggregation, and for this, the sample was embedded in polyester resin and the obtained cross-section, after polishing, was investigated by microscopic techniques (optical microscopy (OM), stereomicroscopy, and scanning electron microscopy with electronic dispersion spectroscopy (SEM-EDS), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, and gas-chromatography with mass spectrometry (GC-MS) in good agreement with data from the literature. The potential result of this study is the identification and quantification of the metallic soap generated as a white deposit (probably salts, a kind of white efflorescence), from the binding medium of the metal carboxylate ionomer, by the crystallization of saturated fatty acids, through polymerization in oil. Six pigments (calcite, lithopone, carbon black, red ochre, vermilion, and ultramarine), present in the sublayers of the samples were identified.

Innovative composites based on polypropylene waste impurified cu HDPE (PPW) combined with two thermoplastic block-copolymers, namely styrene-butadiene-styrene (SBSBC) and styrene-isoprene-styrene (SISBC) block-copolymers, and up to 10 wt% nano-clay, were obtained by melt blending. SBSBC and SISBC with almost the same content of polystyrene (30 wt%) were synthesized by anionic sequential polymerization and used as compatibilizers for PPW. Optical microscopy evaluation of the PPW composites showed that the n-clay was encapsulated into the elastomer. Addition of n-clay, together with SBSBC or SISBC, increased the interphase surface of the components in the PPW composites and enhanced the superficial area/volume ratio, which led to a recycled material with improved performance. The data resulting from differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), mechanical evaluation, and dynamic mechanical analysis (DMA) revealed that PPW reinforcement with n-clay and styrene-diene block-copolymers allows the obtaining of composites with favorable mechanical and thermal properties, and excellent impact strength for potential engineering applications.

In this work, new treatments based on multi-walled carbon nanotubes (MWCNTs), MWCNTs decorated with zinc oxide (ZnO), MWCNTs decorated with hydroxyapatite (HAp) and MWCNTs decorated with silver (Ag) nanoparticles dispersed in PHBHV solution are proposed for improving sound oak wood properties. We hypothesize that the solutions containing decorated MWCNTs will be more efficient as wood consolidants, not only because of the improved mechanical properties of the treated wood but also because of the hydrophobic layer created on the wood surface. In order to test these hypotheses, the treatments’ potential was investigated by a number of complex methods, such as colorimetric parameter measurements, water absorption tests, mechanical tests, artificial aging and antifungal tests. The data confirm that the treated wood materials have moderate stability, and the color differences are not perceived with the naked eye. A significant improvement of the treated samples was observed by water absorption, humidity and mechanical tests compared to untreated wood. The best results were obtained for samples treated by brushing with solutions based on decorated CNTs, which confirms that a uniform and thicker layer is needed on the surface to ensure better protection. The wood behavior with accelerated aging revealed that the control sample degraded faster compared to the other treated samples. Antifungal tests showed that higher growth inhibition was obtained for samples treated with 0.2% MWCNTs_ZnO + PHBHV. Considering all of the obtained results, it can be concluded that the most effective treatment was MWCNTs_ZnO + PHBHV at a nanocomposite concentration of 0.2%, applied by brushing. Thus, wood protection against mold and fungi will be achieved, simultaneously ensuring improved mechanical strength and water barrier properties and therefore maintaining the structural integrity of sound oak wood over time.

(1) Background: In time, stone monuments suffer a process of aging and loss of aesthetic and mechanical properties. In order to restore and stop the loss of their properties, various treatments are used, and in this context, a new class of discovered materials with interesting properties are layered double hydroxides, or LDHs. (2) Methods: The LDHs, prepared by a coprecipitation method, were characterized by the structure by X-ray diffraction, composition by FT-IR spectroscopy and X-ray fluorescence spectroscopy, size by diffuse light scattering, and porosity by N2 adsorption/desorption. Additionally, some microscopy techniques such as optical microscopy and SEM/EDAX were used for surface aspects and morphology, and finally, all these were checked with ImageJ software for representative roughness parameters of the treated surfaces by brushing or incorporation. (3) Results: The prepared materials show different degrees of crystallinity and textural properties, and the dispersion of the material presents good stability in time in water/ethanol mixtures. Treatment with the LDH dispersion applied by brushing led to improvements in the mechanical properties (about a 5% increase in compressive strength), to an increased surface stability (about 30%), and to an improvement in the resistance to freeze–thaw cycles. The textural properties of the specimens’ materials were not altered by these treatments. (4) Conclusions: The order of the consolidation efficacity was CaMgAl-LDH > MgAl-LDH > CaAl-LDH, better for application by brushing than by incorporation.

The aim of this study was to address one of the major challenges of the conservation state of wooden artifacts or artworks namely, the preservation and restoration of wood surfaces. The factors involved in the deterioration of wood are mainly the external factors such as fire, low temperature and microbiological agents, which induce some degradation processes in wood, identified by discoloration, fragility and unsightly appearance. In this study, biodegradable materials based on poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBHV) and composites based on PHBHV and particles (zinc oxide (ZnO), carbonated hydroxyapatite (CHAp) and its metallic derivatives with silver (AgCHAp) and strontium (SrCHAp) were applied on firwood specimens in order to investigate their consolidation capacity. Colorimetric measurements have confirmed that the chosen treatments did not change the colour of the natural wood. The hardness test revealed that the consolidation system increases the mechanical properties of the samples. The used treatments confer a strong hydrophobic character which prevents exfoliation of the wood samples, as confirmed by the performed water absorption test.

Introduction: History can be defined as the study of people who have lived in the past [...]

Introduction: Silver nanoparticles (AgNPs), widely recognized for their antimicrobial and antioxidant capacity, can be prepared following both conventional and unconventional routes and have a multitude of applications in numerous scientific domains, including the catalytic degradation of dyes that result from the textile industry [...]

The external factors from nature are responsible for weathering of different monuments and cause considerable deterioration of Old mural Paintings. This paper presents a virtual reconstruction scheme useful for subsequent restoration processes of the degraded versions of the murals from Matia Loggia, Corvins’Castle, Hunedoara, Romania. The analysis of materials and techniques and the possible deterioration mechanisms are discussed, too, correlated with the colour digital photography and mapping of visible painting degraded area were conducted.

Abstract Over centuries, the external factors such as fire, low temperature, light or microbiological agents, act on the wood and induce some degradation processes, sometimes irreversible, identified by discoloration, fragility and unsightly appearance. Although there are numerous literature reports about different nanomaterials used for preservation and restoration of wood surfaces (calcium hydroxides, magnesium hydroxides, hydroxyapatite, or even organic resins as Paraloid B72), in this paper it is proposed a new system—gold hydroxyapatite (AuHAp), tested on the hazelnut wood samples (young and aged specimens), as a new solution for preservation of some wooden artifacts. This paper addresses a broad range of analytical methods: X-ray diffraction, UV–Vis spectrophotometry, Fourier transformed infrared spectroscopy, Raman spectroscopy, scanning electron microscopy with energy dispersive spectroscopy, chromatic parameters and hardness test. Also, humidity sorption/desorption measurements are used for humidity sorption and desorption evaluation. The adsorption and desorption tests determined the hydroscopic sorption properties of the wood specimens by measuring the mass of the specimens in equilibrium with air at a specific temperature and RH. All the results concluded that after the application of the new system on the hazelnut wood surface, a well distributed and uniform layer consisting from AuHAp systems with a network aspect are observed, which covers the wood vessels and fibers, filling the voids and stopping the wood weathering process, more accentuated at aged wood than at the young species.

In this study, multi-walled carbon nanotubes (MWCNTs) were decorated with different types of nanoparticles (NPs) in order to obtain hybrid materials with improved antimicrobial activity. Structural and morphological analysis, such as Fourier transformed infrared spectroscopy, Raman spectroscopy, X-ray diffraction, transmission electron microscopy, environmental scanning electron microscopy/energy-dispersive X-ray spectroscopy and the Brunauer–Emmett–Teller technique were used in order to investigate the decoration of the nanotubes with NPs. Analysis of the decorated nanotubes showed a narrow size distribution of NPs, 7–13 nm for the nanotubes decorated with zinc oxide (ZnO) NPs, 15–33 nm for the nanotubes decorated with silver (Ag) NPs and 20–35 nm for the nanotubes decorated with hydroxyapatite (HAp) NPs, respectively. The dispersion in water of the obtained nanomaterials was improved for all the decorated MWCNTs, as revealed by the relative absorbance variation in time of the water-dispersed nanomaterials. The obtained nanomaterials showed a good antimicrobial activity; however, the presence of the NPs on the surface of MWCNTs improved the nanocomposites’ activity. The presence of ZnO and Ag nanoparticles enhanced the antimicrobial properties of the material, in clinically relevant microbial strains. Our data proves that such composite nanomaterials are efficient antimicrobial agents, suitable for the therapy of severe infection and biofilms.

Chronic neuropathic pain, particularly peripheral pain, is a cause of great concern for diabetic patients. Current treatments include numerous agents such as capsaicinoids, a known deterrent of neuropathic pain despite the inconvenience associated with local side effects. In this context, the current work aims to elucidate the potential mechanisms involved in cytotoxicity by capsaicin and proposes an efficient formulation of capsaicin in alginate microcapsules, which significantly reduces side effects from capsaicin topical administration. For this, human dermal fibroblast cells were treated with alginate-microencapsulated capsaicin extracts and screened for potential cytotoxic effects produced by the treatment. Cell viability and morphology were examined, as well as oxidative stress status and anti-inflammatory potential. Our results show that the alginate encapsulated formulation of capsaicin exerted lower cytotoxic effects on human dermal fibroblasts as measured by cell viability and reactive oxygen species (ROS) production. Furthermore, the expression profiles of inflammatory cytokines were significantly altered by the treatment as compared with the control culture.

Carbonated hydroxyapatite (CHAp) is an inorganic compound with various applications that presents better homogeneity and consolidating effect than HAp [1]. [...]

In the last decades, the waste electric and electronic equipment (WEEE) has increased substantially due to an accelerated development of the economy and the lifetime of electronics.

Hydroxyapatite is mainly used in biomedical applications because of its very important property—bioactivity. [...]

The history portrays the identity of a culture, of people and various civilizations, which has [...]

The present research describes the components of two types of medicinal plants. [...]

Nowadays, more than ever, cultural heritage is linking humanity to its history. In order to [...]

Carbon nanotubes (CNTs) have attracted attention, due to their structures as well as their ability to present multiple walls. [...]

In the last few years, the preservation of cultural heritage has become an important issue globally, due to the fact that artifacts and monuments are continually threatened by degradation. It is thus very important to find adequate consolidators that are capable of saving and maintaining the natural aspect of these objects. This study aims to provide an updated survey of the main nanomaterials used for the conservation and restoration of cultural heritage. In the last few years, besides the classic nanomaterials used in this field, such as metal nanoparticles (copper and silver) and metal oxides (zinc and aluminum), hydroxyapatite and carbonated derivatives, tubular nanomaterials (such as carbon nanotubes) have been used as a potential consolidate material of cultural heritage. Tubular nanomaterials have attracted attention for use in different fields due to their structures, as well as their ability to present multiple walls. These nanotubes have the necessary properties in preserving cultural heritage, such as superior mechanical and elastic strength (even higher than steel), high hydrophobicity (with a contact angle up to 140°), optical properties (high photodegradation protection), large specific surface area (from 50 to 1315 m2/g, depending on the number of walls) for absorption of other nanomaterials and relatively good biocompatibility.

As the development of the textile industry has progressed, intense concerns have been focusedon the contamination of the environment caused by dye pollutants [...]

Stone monuments represent a big part of the world’s cultural heritage. [...]

Cultural monuments are subject to a degrading phenomenon induced by several factors, such [...]

Recently, numerous studies have been carried out on various. [...]

Graphene and its derivatives have attracted considerable attention in recent years as potentialmaterials for various applications because of their unique physical-chemical properties [...]

The organic part of the waste printed circuit board (WPCB) contains mainly epoxy resin, fiberglass and brominated flame retardants, a composition that makes it quite difficult to reuse [1,2]. [...]

The study aimed to synthesize nanofibers based on styrene-ethylene-butylene-styrene block-copolymers (SEBS) [1] and its composite derivatives, through the electrospinning (Figure 1) process [2]. [...]

Corrosion represents the transformation process of metallic surfaces, caused by the influence of the contact medium. Coins are not exempt from the undesired effect of corrosion. [...]

Hydroxyapatite is a calcium phosphate-based biomaterial utilized both in the medicine field(bone cement, scaffold, drug-delivery) and in the heritage field (stone conservation) [...]

The high amount of plastics, which are durable, lightweight, and cheap materials, is one of themajor current ecological concerns [...]

Hydroxyapatite is an inorganic consolidant used in the restoration of cultural heritage. For thisreason, the study of the effects of different agents on hydroxyapatite is paramount [...]

This study is the first attempt to decipher the effect of particulate matter (PM) composition on people’s health and on historic sites, in correlation with the daily and seasonal microclimate monitoring of the indoor and outdoor areas of the Roman Mosaic Edifice museum (the maritime port of Constanta, Romania). More specifically, the increase of metal concentrations in particulate matter during the summer of 2018 and spring of 2019 in the museum under investigation could possibly be associated with the microclimates of both seasons, with coastal factors, as well as with the anthropic activities specific to the port of Constanta. FTIR and inductively coupled plasma mass spectroscopy (ICP-MS) techniques, used for the investigation of PM2.5−10 samples, revealed high concentrations of Fe, Al-rich, and soluble particles inside the investigated museum area. In this respect, the chemical measurements of the PM2.5−10 masses highlighted high concentrations of heavy metals (i.e., Al, Fe, Zn, Mn, and Pb) and low concentrations of trace metals (i.e., Cr, Ni, Cu, and Cd). Statistical analysis showed that the chemical compositions of the particulate matter in the indoor and outdoor areas of the Roman Mosaic Edifice were influenced by microclimatic conditions, mainly temperature and relative humidity (RH). A potential health risk for tourists is the thermal and humid conditions, alongside the toxic components of the particulate matter. This research seeks to provide solutions for improving the environmental conditions inside the Roman Mosaic Edifice and to offer useful suggestions concerning health promotion and the protection of museum exhibits against possible future deterioration.

The benefits of Capsicum annuum L. are important for human health with its anti-inflammatory [...]

The paper deals with 3D scanning techniques and instruments to survey the complex stuccoes from the architectural building Nanu-Muscel from Bucharest. EXAscan Portable 3D Laser Scanner has been used to exploit the advantages of the 3D surveying techniques and produce digital models and other geometric representations useful for the protection of historic architectures and a correct solution for their restoration. After the parameterization, the scanning of two stucco-objects surface yielded to a network of points. The program analyzes the points and joins them, so the final result being the scanned object in electronic format (digitized), by "Digitized Shape Editor" module in the Catia program. The not useful surfaces have been removed and for the symmetrical reconstruction the mirroring operation was applied.

BACKGROUND: Photodynamic therapy is an alternative treatment of muco-cutaneous tumors that uses a light source able to photoactivate a chemical compound that acts as a photosensitizer. The phthalocyanines append to a wide chemical class that encompasses a large range of compounds; out of them aluminium-substituted disulphonated phthalocyanine possesses a good photosensitizing potential. RESULTS: The destructive effects of PDT with aluminium-substituted disulphonated phthalocyanine are achieved by induction of apoptosis in tumoral cells as assessed by flow cytometry analysis. Using protein microarray we evaluate the possible molecular pathways by which photodynamic therapy activates apoptosis in dysplastic oral keratinocytes cells, leading to the tumoral cells destruction. Among assessed analytes, Bcl-2, P70S6K kinase, Raf-1 and Bad proteins represent the apoptosis related biomolecules that showed expression variations with the greatest amplitude. CONCLUSIONS: Up to date, the intimate molecular apoptotic mechanisms activated by photodynamic therapy with this type of phthalocyanine in dysplastic human oral keratinocytes are not completely elucidated. With protein microarray as high-throughput proteomic approach a better understanding of the manner in which photodynamic therapy leads to tumoral cell destruction can be obtained, by depicting apoptotic molecules that can be potentially triggered in future anti-tumoral therapies.

Considering that the large quantity of waste electrical and electronic equipment plastics generated annually causes increasing environmental concerns for their recycling and also for preserving of raw material resources, decreasing of energy consumption, or saving the virgin materials used, the present challenge is considered to be the recovery of individual polymers from waste electrical and electronic equipment. This study aims to provide an update of the main identification methods of waste electrical and electronic equipment such as spectroscopic fingerprinting, thermal study, and sample techniques (like identification code and burning test), and the characteristic values in the case of the different analyses of the polymers commonly used in electrical and electronic equipment. Additionally, the quality of the identification is very important, as, depending on this, new materials with suitable properties can be obtained to be used in different industrial applications. The latest research in the field demonstrated that a complete characterization of individual WEEE (Waste Electric and Electronic Equipment) components is important to obtain information on the chemical and physical properties compared to the original polymers and their compounds. The future directions are heading towards reducing the costs by recycling single polymer plastic waste fractions that can replace virgin plastic at a ratio of almost 1:1.

In the light of the recent concerns in the assessment of the new conservation treatments and of the development and application of methodologies, technologies, models and tools for CH damage assessment, this paper will deal with some innovative topics related to the digital models for protecting cultural heritage assets in front of various damages. Application of new technologies and digitalization of Basarabi monument is a preventive measure, helping us to build a virtual reconstructions as model for its potential reconstruction and preserving, to give access for the widest possible audience. It will be discussed the new technologies, as the non-destructive diagnosis technologies for the safe conservation a this historic, cultural and architectural – Basarabi churches. For the micro-climatic measurements, a number of sensors have been well distributed inside and outside and a diagram of humidity an temperature is evaluated. The practical examples of restoration and preservation and innovative solutions for the consolidation of this architectural monument, in relation with digitalization (by on-site and remotely data collection, virtual reality and documentation of the heritage). For a digital image of this monument, both a 3D laser scanner and some common digital photos are used, in order to obtain the 3D model of the church, and of the envelope of the church that should be applied over it to stop the seriously damage processes.

Helping improve humanity is one of the promises of nanotech-nology and nanomedicine. This paper will highlight some of the research findings in the nanomedicine area by testing some single- and multi-walls carbon nanotubues in rats cerebral aneurisms.

A molecular motor can be defined as an assembly of a discrete number of molecular components designed to perform mechanical movements under control of appropriate energy inputs.

The time-resolved photothermal methods are used in order to establish the yield of intersystem (singlet-triplet) crossing of dyes that are candidates for the application in photodynamic therapy. It is known that molecules with long living triplet state cause efficient photosensitization by direct interaction with the cells or by singlet oxygen generation.

In this paper we report for the first time on a mixed complex between the cationic porphyrin 5, 10, 15, 20-tetra-N- -methyl-pyrydinium-p-il porphyrin (TMPyP) and a new metal phthalocyanine with four 16-membered diazadithia macrocycles (denoted here as Pc16), in order to obtain an active complex with an intense absorption on the lower energy side of the visible spectrum and with a higher sensitivity in photodynamic therapy of cancer. The dimerization constant for Pc16 and also the ratio between the oscillator strengths for monomeric and dimeric forms of this compound, were evaluated. The ratio between these oscillator strengths was 2.01 showing a certain dimerization process. The Job mathematical method allowed the establishment of the stoichiometry and the formation constants for the heteroaggregates between the porphyrin and the phthalocy- anine (a diad between one phthalocyanine molecule and one porphyrin molecule and a triad between two phthalocyanine molecules and only one porphyrin molecule). The coulombic attraction resulting from the p-p interaction of the two highly conjugated macrocycles and from the interaction between the substituents, favors a face-to-face geometry.