Search Results (99)

Background: Total glycosides of peony (TGP) have therapeutic potential for immune-related and inflammatory skin diseases, but their skin absorption is not satisfactory. This study aims to investigate how Evodia rutaecarpa volatile oil (VO-ER) enhances the permeability of TGP. Methods: Safety assessment was conducted through cell delivery and skin erythema tests. The chemical composition of VO-ER was identified via GC-MS. The study was conducted using modified Franz diffusion cells, microdialysis, confocal laser scanning microscopy (CLSM), attenuated total reflection–Fourier transform infrared spectroscopy (ATR-FTIR), molecular docking and molecular dynamics simulations (MD), laser Doppler flowmetry (LDF), and the western blotting method. Results: The study found that VO-ER promotes the permeation of total glycosides of peony in a concentration-dependent manner by disrupting the intercellular lipid tissue structure, downregulating the expression of claudin-1, claudin-7, and occludin, and improving local microcirculation, thereby promoting the absorption of TGP. Conclusions: VO-ER enhances the transdermal absorption of TGP through multiple mechanisms, such as disrupting the skin lipid barrier, downregulating tight junction proteins, and improving local skin microcirculation. This study provides a theoretical basis for VO-ER as a safe and effective new transdermal penetration enhancer, offering support for the development of topical preparations containing Evodia rutaecarpa and Paeonia lactiflora. Full article

The study and preservation of illuminated manuscripts, particularly miniatures on parchment, are crucial for understanding the artistic, cultural, and technological history of the past. This research investigates the materials used in a 16th-century illuminated scroll, analyzing both the miniatures and the written text through non-invasive techniques. A multi-analytical approach was applied, including optical microscopy, Hypercolorimetric Multispectral Imaging (HMI), infrared reflectography in the 950–1700 nm range, Fiber Optics Reflectance Spectroscopy (FORS), macro X-ray fluorescence (MA-XRF) spectroscopy, Raman spectroscopy, and External Reflection Fourier Transform Infrared (ER-FTIR) spectroscopy. These methods provided a comprehensive characterization of the painting materials’ chemical composition and the artistic techniques utilized, revealing new information on Renaissance materials and practices. The detected mineral pigments primarily include smalt, vermilion, lead white, and minium, which are consistent with materials commonly found in illuminated manuscripts. Aluminosilicate and calcite were identified as fillers or substrates utilized for organic dyes, particularly those generating pink hues. An uncommon finding was the green pigment, which was identified as copper hydroxynitrate. Furthermore, gold and silver were extensively employed in the decorative elements, both as metal foils and in shell pigment form. Finally, the capital letters were executed using smalt and vermilion, while the black text ink was characterized as iron gall ink, a composition typically employed on parchment supports. Full article

Influence of surface pretreatment Hydrofluoric acid (HFA), Erbium yttrium scandium gallium garnet (Er, Cr: YSGG) laser (ECL), and Phthalocyanine (Pc) photosensitizer (Ps) activated by Low-level laser therapy (LLLT) via a light-emitting diode (LED) device on surface roughness (Ra) and shear bond strength (SBS) of ceramic bracket bonded to enamel via unmodified and Sepiolite-modified adhesive. Sixty non-cavitated human maxillary premolars were obtained. Ninety ceramic brackets were classified into three groups based on different pretreatment methods: Group 1: HFA; Group 2: ECL; and Group 3: Pc-LLLT. Twenty samples from each cohort were allocated into two subgroups by adhesive type: unmodified Transbond XT(A) and adhesive-modified Sep-NPs(B) (n = 10). Ra was measured using profilometry followed by surface topography via SEM, SBS via universal testing machine, and degree of conversion (DC) through FTIR spectroscopy. ANOVA and Tukey’s post hoc tests compared Ra, SBS, and DC across groups (p ˂ 0.05). Maximum Ra was observed in the ECL group (1087.43 ± 0.043 µm), while Group 3 (Pc-LLLT) showed the lowest Ra (706.53 ± 0.054 µm). Maximum SBS was recorded in Group 2B (ECL + SepNPs modified adhesive) (8.79 ± 0.48 MPa), while Group 3A (Pc-LLLT + unmodified adhesive) (5.23 ± 0.32 MPa) showed minimum bond integrity. ECL serves as an appropriate substitute for HFA in improving Ra and SBS of ceramic brackets to enamel. SepNPs improved the SBS of orthodontic adhesive to enamel with no significant difference in DC. Full article

We have investigated the structural, morphological, magnetic, and up-conversion luminescence properties of the Yb³⁺/Er³⁺-doped LiGdF₄ nanocrystals precipitated in the silica glassy matrix. Morphological analysis showed uniform distribution of LiGdF₄ nanocrystals (tens of nm in size), embedded in silica glass matrix. FTIR spectroscopy analysis showed trifluoracetates thermolysis with silica lattice formation and structural analysis by XRD is consistent with the LiGdF₄ crystallization process, most likely through an autocatalytic reaction. The stress and crystalline lattice distortion are assigned to the doping and glass matrix environment where the growth process occurs. The EPR spectra associated with the Gd³⁺ ions have shown a well-defined spectrum in the xerogel, associated with the trifluoroacetate ligand environment. In the LiGdF₄ nanocrystals, the broad and unresolved spectrum is due to an envelope of unresolved anisotropic fine structure and a high dipole–dipole interaction between the Gd³⁺/Yb³⁺/Er³⁺ paramagnetic ions. Under 980 nm laser light pumping, we observed the characteristic “blue”, “green” and “red” up-conversion luminescences of the Er³⁺ ions through Yb → Er energy transfer process, that imply three and two-photon process; near UV up-conversion luminescence of Gd³⁺ is observed at about 280–300 nm where Yb → Er and Er → Gd energy transfer is involved. The UC luminescence properties can be improved up to two times by additional Yttrium co-doping due to the induced crystal field distortion. Full article

Occupational exposure to soil-borne pesticides remains a critical safety and process-management challenge in industrial and agro-industrial settings. This work proposes a process-integrated analytical workflow that couples comparative instrumental identification of soil xenobiotics with an occupational risk assessment framework. We comparatively evaluate GC-MS (gas chromatography–mass spectrometry), HPLC (high performance liquid chromatography), FTIR (Fourier-Transform Infrared Spectroscopy), LC-MS/MS (Liquid Chromatography coupled with tandem Mass Spectrometry), and ICP-MS (Inductively Coupled Plasma Mass Spectrometry) against matrix complexity, sensitivity, cost, and throughput, and implement the Quick, easy, cheap, effective, rugged, safe (QuEChERS) method-based sample preparation followed by GC-MS and LC-MS/MS to demonstrate applicability on representative soil and food-chain samples. Complementary risk tools (toxicity–probability matrices, exposure pathway diagrams) and an integrated monitoring scheme that combines environmental data with biomonitoring are used to link concentrations to exposure potential and control priorities. In a soil case sample, low-level organochlorines were detected with total DDT at 0.010 mg/kg and total HCH at 0.003 mg/kg, illustrating how analytical outputs feed decision matrices for prioritizing interventions. Case analyses from agricultural and industrial contexts indicate that targeted substitution, optimized application, ventilation and dust control, PPE (personal protective equipment) adherence, and worker training can measurably reduce symptoms and biomarkers of exposure. Overall, a complementary, process-analytical approach—integrating sensitive multi-technique detection with exposure assessment and continuous monitoring—supports proactive risk management and aligns with process systems and monitoring themes. Recommendations include standardizing workflows, coupling routine environmental monitoring with biomonitoring where feasible, and embedding preventive policies and training into industrial management systems. Full article

This study reports the discovery, contextualization, and archaeometric analysis of a unique metal pilgrim flask recovered from the sacred well of Santa Cristina (Paulilatino, Sardinia, Italy), a major sanctuary complex of the Nuragic period. Misidentified for several decades following its 20th-century excavation, the object has now been reinterpreted as a nearly intact, full-scale pilgrim flask manufactured from pewter—a material previously unrecorded in Sardinian protohistoric contexts. Typological comparison with related artefacts from the Levant, Cyprus, and Etruria reveals close formal and morphological affinities with Sardinian ceramic flasks and, in particular, with miniature bronze flasks documented in Nuragic and Villanovan assemblages. The morphological congruence suggests that the Santa Cristina vessel may have functioned as a prototype or symbolic referent for these miniature exemplars. The associated presence of eastern Mediterranean-style figurines and other imported materials further underscores the sanctuary’s involvement in elite ritual practices and participation in long-distance exchange networks. From a technological perspective, selected areas of the vessel were investigated using non-destructive Energy-Dispersive X-Ray Fluorescence (EDXRF) analysis, supported by Monte Carlo simulation of the in situ measurements, and External Reflectance Fourier-Transform Infrared (ER-FTIR) spectroscopy. The combined results indicate a pewter alloy characterized by elevated tin and lead contents, confirming the object’s exceptional technological status within the Sardinian protohistoric metallurgical repertoire. Full article

Surface organic coatings (SOCs) composed of drying oils, resins, and bitumen were commonly applied to small Renaissance bronze sculptures to enhance their visual and physical properties, producing dark, lustrous surfaces that were both esthetic and protective. Yet, the identification of these coatings remains challenging due to aging, conservation interventions, and the damage caused by physical sampling. This study presents a reproducible, non-destructive protocol for characterizing SOCs on metal substrates using external reflection Fourier transform infrared spectroscopy (ER-FTIR) and fiber optic reflectance spectroscopy (FORS). Twenty-seven reference coating mock-ups of linseed oil, walnut oil, mastic resin, pine resin, and bitumen were stoved onto bronze coupons and artificially aged. Spectra were analyzed across the visible/near-infrared (VIS-NIR) (~400–1000 nm), short-wave-infrared (SWIR) (~1000–2500 nm), and mid-infrared (MIR) (~2.5–25 µm) ranges, with key diagnostic features identified for each component and blend, including primary absorptions, combination bands, and overtones. ER-FTIR proved highly effective in detecting oil–resin mixtures and later wax coatings through characteristic bands in the MIR, while FORS, enhanced by first-derivative processing, successfully differentiated triterpenoid and diterpenoid resins and identified multi-component SOCs in the SWIR region. The reference spectral database generated in this study is intended to serve as a comparative tool for future non-invasive analysis of organic coatings on metal surfaces and to demonstrate that ER-FTIR and FORS, used in tandem, offer a practical and scalable framework for the non-destructive identification of SOCs. Full article

Codex 462 of the Fondo Hortus Pisanus of the Biblioteca Universitaria of Pisa is a precious example of a 16th century illustrated herbal, Icones variarum plantarum, containing 35 tempera paintings by the German soldier Georg Dyckman, an amateur but highly talented artist. The manuscript was recently restored on the occasion of an international exhibition; the necessary preliminary studies for the restoration included a series of in situ diagnostic studies using contactless techniques (digital microscope, multispectral imaging, XRF, Raman and ER-FTIR). These analyses proved useful in deepening the knowledge of the materials and the execution technique of this type of illustrated herbals and in choosing the most appropriate solutions during the restoration phase. In view of the growing interest in this type of historical evidence, which involves both art history and the history of science, this study offers an interesting new perspective on the subject, useful both from a technical point of view for future conservation and for analytical and historical artistic studies. Full article

Epoxy resins (ERs) are esteemed for their mechanical robustness and adhesive qualities, particularly in steel bridge deck applications. Nonetheless, their intrinsic brittleness limits broader utility. This study addresses this limitation by modulating ER crosslink density through adjustments in curing agent concentration, incorporation of hyperbranched polymers (HBPs), and optimization of curing conditions. Employing a multi-objective optimization strategy, this research aims to enhance toughness while minimizing strength degradation. Non-isothermal curing kinetics, realized using the differential scanning calorimetry (DSC) method, attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), tensile testing, and thermogravimetric analysis (TGA), were employed to investigate the effects of curing agent and HBP content on the curing reaction, mechanical properties, and thermal stability, respectively. Response surface methodology facilitated comprehensive optimization. Findings indicate that both curing agent and HBP contents significantly influence curing dynamics and mechanical performance. Curing agent content below 40% or above 50% can induce side reactions, adversely affecting properties. While a curing agent content exceeding 45% or an HBP content exceeding 5% improves the toughness of ER, these increases concurrently reduce mechanical strength and thermal stability. The study identifies an optimal formulation comprising 45.21% curing agent, a curing temperature of 60.45 °C, and 5.77% HBP content. Full article

The conversion of CO₂ through the electrochemical reduction reaction (ECO₂RR) into chemicals or fuels is regarded as one of the effective ways to decrease atmospheric CO₂ concentrations. In this study, a Cu-Sn bimetallic electrocatalyst (ER-Sn_mCu_nO_x-t/CC) was successfully prepared via a chemical foaming method and electrochemical reduction. SEM showed that ER-Sn₁Cu₁O_x-500 nanoparticles were uniformly distributed on the carbon cloth, which benefited from foaming. The XPS results demonstrated the synergistic interaction between Cu and Sn and the existence of oxygen vacancies originating from the electroreduction. Due to the above features, ER-Sn₁Cu₁O_x-500/CC achieved 84.1% FE for HCOOH at −1.1 V vs. RHE, and the corresponding J_HCOOH was up to 32.4 mA·cm⁻² in the H-type cell. Especially in the flow cell, ER-Sn₁Cu₁O_x-500/GDE could reach a high J_HCOOH of 190 mA·cm⁻² at −1.1 V vs. RHE and maintained J_HCOOH higher than 100 mA·cm⁻² for 24 h with a formic acid selectivity over 70%, indicating both excellent catalytic activity and high HCOOH selectivity. In situ FTIR results revealed that synergism between Cu and Sn could regulate the adsorption of intermediates, thus enhancing the catalytic performance of ER-Sn₁Cu₁O_x-500 for ECO₂RR. Full article

This study successfully synthesizes SiO₂-encapsulated nano-phase change materials (NPCMs) via a sol–gel method, using paraffin as the thermal storage medium. The encapsulation process is validated through FTIR, XRD, and XPS analyses, confirming the formation of an amorphous SiO₂ shell without any chemical interaction between the core and shell. SEM imaging reveals a well-defined core–shell structure with uniform spherical geometry, with the smallest particle size (190 nm) observed in the sample with a 4:1 paraffin/SiO₂ ratio (PARSI-4). TGA results demonstrate enhanced thermal stability, with thicker SiO₂ shells effectively protecting against thermal degradation. The DSC analysis indicates that an increased core–shell ratio improves thermal performance, with PARSI-4 exhibiting the highest melting (160.86 J/g) and solidifying (153.93 J/g) enthalpies. The encapsulation ratio (ER) and encapsulation efficiency (EE) have been accomplished at 87.83% and 87.04%, respectively, in the PARSI-4 sample. Thermal cycling tests confirm the material’s long-term stability, with 98.16% enthalpy retention even after 100 cycles. Additionally, leakage resistance tests validate the structural integrity of the encapsulated paraffin, preventing spillage at elevated temperatures. These findings demonstrate the potential of SiO₂-encapsulated NPCMs for efficient thermal energy storage (TES), making them promising candidates for sustainable and energy-efficient applications. Full article

The purpose of this research is to study the modifying effect of oligoesters with reactive groups based on epoxy aliphatic resin and oligoesters with dicarboxylic acids with different molecular weights (adipic, sebacic, and tetradecanedioic acids). Adducts of oligoesters with terminal epoxy groups and epoxy resin (ER) were prepared. The structures of the intermediates and modifiers were characterized by FTIR, ¹H NMR, ¹³C NMR, TGA, DMA, and SEM. The single-phase structure of the modified polymers was confirmed using the DMA, TGA, and SEM methods. It was shown that for modified polymers, a pattern of plastic deformation is observed, in contrast to the brittle destruction of the initial polymer. It has been found that elongation at break, impact strength, work of fracture, and shear strength increase throughout the studied concentration range (at 50% modifier content, elongation at break and shear strength increase by ~450% and ~150%, respectively, compared with an unmodified polymer). The results obtained demonstrate that synthesized modifiers with reactive epoxy groups can contribute to the creation of new cold-cured epoxy materials with an improved complex of properties for various industries. Full article

The development of an energy-saving method to recycle expensive carbon fibers (CFs) from end-of-life thermosetting resin-based CF-reinforced composites (CFRCs) is strongly desired because of the environmental and economic issues. The replacement of traditional thermosetting matrixes with controllably degradable epoxy resins provides a promising solution to this challenging task. In this work, a liquid acetal-containing semi-cycloaliphatic epoxy resin (H-ER) is designed and synthesized. After curing, H-ER shows simultaneously increased thermal stability, shearing strength, flexural strength, strain at break, and critical stress intensity factors by 126%, 26.5%, 17.0%, and 29.5%, respectively, in comparison with ERL-4221. Particularly, the cured H-ER is sufficiently resistant to organic solvents, bases, and weak acids but degrades rapidly in a modestly strong acidic aqueous solution, and the rate of degradation is controlled by modulating the acidity. GC-MS and FTIR spectra demonstrate that the degradation is indeed due to the cleavage of acetal linkages in the network, and the degradation-generated benzaldehyde may be reused as a raw material for the synthesis of the H-ER resin. More importantly, for the CFRCs using H-ER as a matrix, the CFs are readily recovered without detectable damage and are able to be recycled for CFRC fabrication. Full article

This study focuses on assessing the indoor air quality in a storage room (SR) belonging to Museo Nazionale Scienza e Tecnologia Leonardo da Vinci in Milan (MUST), covering pollutants originating from outdoor sources and emissions from historical plastic objects made from cellulose acetate (CA), cellulose nitrate (CN), and urea–formaldehyde (UF) stored in metal cabinets. The concentrations of SO₂ (sulphur dioxide), NO₂ (nitrogen dioxide), NOx (nitrogen oxides), HONO (nitrous acid), HNO₃ (nitric acid), O₃ (ozone), NH₃ (ammonia), CH₃COOH (acetic acid), and HCOOH (formic acid) were determined. The concentrations of SO₂, O₃, and NOx measured inside the metal cabinets were consistently lower compared to the other sampling sites. This result was expected due to their reactivity and the lack of internal sources. The SR and metal cabinets showed similar concentrations of NO and NO₂, except for CA, where a high NO concentration was detected. The interaction between the CA surfaces and NO₂ altered the distribution of NO and NO₂, leading to a significant increase in NO. The presence of HNO₃ potentially led to the formation of ammonium nitrate, as confirmed by ER-FTIR measurements. High levels of HONO and HNO₃ in CN and NH₃ in the UF indicate object deterioration, while elevated concentrations of CH₃COOH in CA and HCOOH in the SR suggest specific degradation pathways for cellulose acetate and other organic materials, respectively. These results could direct conservators towards the most appropriate practical actions. Full article

Oral squamous cell carcinoma (OSCC) is a common malignancy in the oral cavity. Photodynamic therapy (PDT) is a new alternative for the treatment of diseases using photosensitizers (PS) and light. In this study, we used a photosensitizer complex (Ce6-MnNPs—Chlorin e6 combined with up-conversion nanoparticles NaYF₄:Yb/Er/Mn) to investigate the therapeutic effectiveness of this treatment against oral cancer cells. We also investigated the mechanism of action of near-infrared light PDT (NIR-PDT) combined with the Ce6-MnNPs. After determining a suitable concentration of Ce6-MnNPs using an MTT assay, human oral squamous cell carcinoma cells (HSC-3) were treated with NIR-PDT with Ce6-MnNPs. We examined the characteristics of Ce6-MnNPs by transmission electron microscopy (TEM); a zeta potential and particle size analyzer; Fourier-transform infrared spectroscopy (FTIR); cell viability by MTT assay; and apoptosis by FITC-Annexin V/PI assay. The mitochondrial membrane potential (MMP), apoptosis-related mRNA level (Bax and Bcl-2) and p53 protein were also researched. NIR-PDT with 0.5 ng/µL Ce6-MnNPs inhibited the proliferation of HSC-3 (p < 0.05). After treatment with NIR-PDT, changes in the mitochondrial membrane potential and apoptosis occurred (p < 0.01). The ratio of Bax/Bcl-2 and p53-positive cells increased (p < 0.01). These results suggest that this treatment can induce apoptosis of oral cancer cells. Full article