Using easy ambient sonic-spray ionization mass spectrometry (EASI-MS), fast and non-destructive fingerprinting identification and aging of ballpoint pen ink writings have been performed directly from paper surfaces under ordinary ambient conditions. EASI-MS data obtained directly from the ink lines showed that pens from different brands provide typical ink chemical profiles. Accelerated ink aging has also been monitored by EASI-MS revealing contrasting degradation behaviors for six different common ink dyes. As demonstrated for Basic Violet 3, some dyes display a cascade of degradation products whose abundances increase linearly with time thus functioning as 'chemical clocks' for ink aging. Analysis of questionable documents has confirmed the ink aging capabilities of EASI-MS. The order of superimposition at a crossing point has also been determined by EASI-MS. For two superimposed ink lines, continuous EASI-MS analysis has also shown that the EASI spray is able to penetrate through the layers and therefore both ink layers could be characterized.
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http://dx.doi.org/10.1039/b923398a | DOI Listing |
Acta Biomater
January 2025
Ophthalmology Department, The First Affiliated Hospital of Jinan University, Guangzhou, China; Key Laboratory for Regenerative Medicine of Ministry of Education, Jinan University, Guangzhou, China; Institute of Ophthalmology, Medical College, Jinan University, Guangzhou, China; Aier School of Ophthalmology, Central South University, Changsha, China. Electronic address:
The shortage of corneal donors and the limitations in tissue engineering grafts, such as biocompatibility and mechanical properties, pose significant challenges in corneal transplantation. Here, for the first time, we investigate the effect of Rho kinase inhibitor Y-27632 and a dual media culture approach, including proliferative media (M1) and stabilizing media (M2), on rabbit limbal epithelial stem cells (LESCs), aiming to explore the feasibility of constructing corneal cell sheets in vitro through auto-bioprinting and assessing their corneal wound healing capacity in vivo. Y-27632 has primarily demonstrated significantly enhanced LESCs growth, proliferation, and reduced apoptosis.
View Article and Find Full Text PDFChemSusChem
December 2024
UESTC: University of Electronic Science and Technology of China, Institute of Fundamental and Frontier Sciences, Jianshe Road, Chengdu, CHINA.
Soft Matter
November 2024
Chemistry and Nanoscience Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, Colorado 80401, USA.
Iridium oxide (IrO) is recognized as a state-of-art catalyst for anodes of low-temperature polymer-electrolyte membrane water electrolyzers (PEMWE), one of the promising clean energy technologies to produce hydrogen, a critical energy carrier for decarbonization. However, typical IrO ink formulations are challenging to process in liquid-film coating processes because of their poor stability against gravitational settling and low viscosities. Here we report on time evolution of the microstructure of concentrated IrO inks in a water-rich dispersion medium, probed using a combination of rheology and X-ray scattering for up to four days.
View Article and Find Full Text PDFForensic Sci Int
November 2024
Aarhus University, Aarhus Institute of Advanced Studies, Høegh-Guldbergs Gade 6B, 8000 Aarhus C, Denmark.
Fraudulent activities often involve document manipulation, which poses a significant challenge to forensic science. To address this issue, a novel method was developed that combines intended artificial UV pre-degradation, digital color analysis (DCA) of stroke images, and various machine learning (ML) models. This method can cluster blue ballpoint pen inks and predict their photodegradation time.
View Article and Find Full Text PDFAging (Albany NY)
September 2024
Department of Urology, Shengjing Hospital, China Medical University, Shenyang, Liaoning 110004, China.
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