98%
921
2 minutes
20
We propose ATR-FTIR spectroscopy for the characterization of the spectral changes in alkyd resin from the Griffin Alkyd Fast Drying Oil Colour range (Winsor & Newton), occurring over 550 days (∼18 months) of natural ageing and over six months of artificial ageing under an acetic acid atmosphere. Acetic acid is one of the atmospheric pollutants found inside museums in concentrations that can have a significant effect on the works exhibited. During natural ageing we observed an increase and broadening of the OH group band around 3300 cm(-1) and an increase in bands in the region 1730-1680 cm(-1) due to carbonyl stretching. We found a broad band around 1635 cm(-1) likely due to CO stretching vibrations of β dichetons. These spectral changes are the result of autooxidation reactions during natural ageing and crosslinking, which then form f alcohols and carbonyl species. The increase in absorbance at 1635 cm(-1) was selected as a parameter to monitor the ageing process of paintings prepared with FDOC, without the need for any extractive procedure. FTIR spectra of paint replicas kept under an acetic acid atmosphere indicated the chemical groups involved in the reaction with acid, thus suggesting which spectral FTIR regions could be investigated in order to follow any degradation in real paintings. A red paint sample from a hyper-realistic artwork ("Racconta storie", 2003) by the Italian painter Patrizia Zara was investigated by FTIR in order to evaluate the effects of 10 years natural ageing on alkyd colours. The results obtained suggested that after the end of chemical drying (autooxidation), alkyd colours are very stable.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.saa.2014.03.123 | DOI Listing |
Adv Sci (Weinh)
September 2025
Key Laboratory of Emergency and Trauma of Ministry of Education, The First Affiliated Hospital, NHC Key Laboratory of Tropical Disease Control, School of Tropical Medicine & The Second Affiliated Hospital, Hainan Medical University, Haikou, 571199, China.
Circulating tumor cells (CTCs) carry intact tumor molecular information, making them invaluable for personalized cancer monitoring. However, conventional capture methods, relying on passive diffusion, suffer from low efficiency due to insufficient collision frequency, severely limiting clinical utility. Herein, a magnetic micromotor-functionalized DNA-array hunter (MMDA hunter) is developed by integrating enzyme-propelled micromotors, magnetic nanoparticles, and nucleic acid aptamers into distinct functional partitions of a DNA tile self-assembly structure.
View Article and Find Full Text PDFAdv Sci (Weinh)
September 2025
Department of Physics, State Key Laboratory of Surface Physics, and Key Laboratory for Computational Physical Science (Ministry of Education), Fudan University, 2005 Songhu Road, Yangpu District, Shanghai, 200433, China.
Emerging evidence indicates that liquid-liquid phase separation of α-synuclein occurs during the nucleation step of its aggregation, a pivotal step in the onset of Parkinson's disease. Elucidating the molecular determinants governing this process is essential for understanding the pathological mechanisms of diseases and developing therapeutic strategies that target early-stage aggregation. While previous studies have identified residues critical for α-synuclein amyloid formation, the key residues and molecular drivers of its phase separation remain largely unexplored.
View Article and Find Full Text PDFJ Cosmet Dermatol
September 2025
Department of Dermatology, Nantong Third People's Hospital, Affiliated Nantong Hospital 3 of Nantong University, Nantong, China.
Purpose: To evaluate the efficacy and underlying mechanism of advanced optimal pulse technology intense pulsed light (AOPT) in low-energy triple-pulse long-width mode (AOPT-LTL) for melasma treatment.
Methods: An in vivo guinea pig model of melasma was established through progesterone injection and ultraviolet B radiation. Three sessions of AOPT-LTL treatment were performed weekly.
Nan Fang Yi Ke Da Xue Xue Bao
August 2025
Department of Pathogenic Biology & Key Laboratory of Tropical Translational Medicine of Ministry of Education, School of Basic Medicine and Life Sciences, Hainan Medical University. Haikou 571199, China.
Objectives: To elucidate the anti-aging effect of β-sitosterol (BS), an important component in the fruits of Miq., in and its regulatory effect on ETS-5 gene to modulate ferroptosis.
Methods: treated with 10 µg/mL BS were monitored for survival time and changes in body length, motility, and reproductive function.
Nan Fang Yi Ke Da Xue Xue Bao
August 2025
Department of Encephalopathy, First Affiliated Hospital of Henan University of Chinese Medicine, Zhengzhou 450000, China.
Objectives: To exple the mechanism of Granules (QXZG) for enhancing synaptic plasticity in aging rats.
Methods: Forty SD rats were randomized into control group, aging model group, donepezil treatment group, and QXZG treatment group (=10). Except for the control rats, all the rats were subjected to daily intraperitoneal injection of D-galactose for 8 consecutive weeks to induce brain aging, and donepezil hydrochloride and QXZG suspension were administered by gavage during modeling.