Surface-enhanced Raman scattering (SERS) spectra, taken with 632.8 nm excitation are reported for the water-soluble tetrakis(3-N-methylpyridyl)porphyrin chloride (TMPyP(3)), tetrakis(4-N-methylpyridyl)porphyrin chloride (TMPyP(4)) and Sn(IV)tetrakis(4-N-methylpyridyl)porphyrin chloride (Sn(IV)TMPyP(4)) using an electrochemically prepared Ag surface with an area ca. 12.56 mm2. It was found that the spectra vary as increasing amounts of the compounds are placed on the surface, with surface concentrations in the approximate range 1000-5 pmol/12.56 mm2. We suggest that the reasons for the changes be that the reaction means between porphyrin molecules and Ag surface is different and the porphyrin macrocyclic molecules adopt different orientation as the surface concentrations decrease.
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Environ Monit Assess
January 2025
Amity Institute of Biotechnology, Amity University, Noida, Uttar Pradesh, India.
In recent years, heightened concern has emerged regarding the pervasive presence of microplastics in the environment, particularly in aquatic ecosystems. This concern has prompted extensive scientific inquiry into microplastics' ecological and physiological implications, including threats to biodiversity. The robust adsorption capacity of microplastic surfaces facilitates their widespread distribution throughout aquatic ecosystems, acting also as carriers of organic pollutants.
View Article and Find Full Text PDFTree Physiol
January 2025
School of Natural Resources, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China.
Seasonal variations of nutrients in different organs are an essential strategy for temperate trees to maintain growth and function. The seasonal variations and variability (i.e.
View Article and Find Full Text PDFFront Toxicol
January 2025
Institute of Biochemistry and Biotechnology, University of Veterinary and Animal Sciences, Lahore, Pakistan.
Plastics are globally considered a significant threat, particularly to metropolitan areas, due to the extensive use of plastic products. This research is the first of its kind to document microplastics contamination and its effects on Red wettled lapwing (Vanellus indicus). The concentration of microplastics (MPs) was measured from surface water at different locations including canals and drains, which are the primary sources of MPs pollution in the metropolitan city Lahore, Pakistan.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Institute for Theoretical Physics, Georg-August University of Göttingen, 37077 Göttingen, Germany.
A Single-Chain-in-Mean-Field (SCMF) algorithm was introduced to study block copolymer electrolytes in nonequilibrium conditions. This method self-consistently combines a particle-based description of the polymer with a generalized diffusion equation for the ionic fluxes, thus exploiting the time scale separation between fast ion motion and the slow polymer relaxation and self-assembly. We apply this computational method to study ion fluxes in electrochemical cells containing poly(ethylene oxide)-polystyrene (PEO-PS) block copolymers with added lithium salt.
View Article and Find Full Text PDFComput Methods Biomech Biomed Engin
January 2025
Department of Endodontics, School of Dental Medicine, Bahçeşehir University, Istanbul, Türkiye.
Biomechanical properties of a mandibular first molar with different cavity designs [traditional access cavities (TEC-I & TEC-II), ninja access cavity (NEC), conservative access cavity (CEC), truss access cavity (Tr-EC), caries-driven access cavity (Cd-EC), caries-driven truss access cavity (Cd-TrEC)] were compared using finite element (FE) analysis. Models were subjected to three different loads. The highest stress distribution was observed on the enamel surface of the Cd-EC design and the dentin surface of the TEC-II.
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