Mechanochemical reactions by ball milling are becoming increasingly popular across a wide range of chemical sciences, but understanding and evaluation of temperature during such processes remains a persistent challenge, especially for organic and metal-organic materials. Here, we describe the first methodology for precise real-time measurement of sample temperature during mechanochemical transformations. Using this technique coupled with real-time reaction monitoring by synchrotron X-ray diffraction and numerical simulations of heat flow, we have shown that the temperature profiles of mechanochemical reactions are dominantly determined by the energy dissipated through friction between the sample and the moving milling assembly, while the reaction enthalpy will usually be comparatively insignificant. With the changes in composition during mechanochemical reactions, frictional properties of the milled material change, leading to either better or worse energy absorption upon collisions in the process of milling. This approach explains unexpected and rapid temperature drops during exothermic transformations of ZIF-8 polymorphs. Since reaction kinetics are highly sensitive to changes in temperature, precise temperature profiles provided here will be mandatory to understand kinetics and its changes during milling, and will aid in developing the comprehensive model of mechanochemical reactivity.
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http://dx.doi.org/10.1039/c7sc05312f | DOI Listing |
Int J Pharm
January 2025
Soft Matter Chemistry, Department of Chemistry, and Helsinki Institute of Sustainability Science, Faculty of Science, University of Helsinki, PB55 00014 Helsinki, Finland. Electronic address:
Drug loaded microfiber scaffolds have potential for sublingual drug delivery due to their fast dissolution time and tunable porosity. Such microfiber scaffolds can be prepared by melt electrowriting (MEW), wherein a polymer melt is electrostatically drawn out of a syringe onto a computer controlled moving collector. The fabrication of such scaffolds via MEW has previously been shown for a polymer with a glass transition temperature (T) just above room temperature, making handling challenging.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
International Research Center for Marine Biosciences, Shanghai Ocean University, Ministry of Science and Technology, College of Fisheries and Life Science, Shanghai 201306, China; Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai 201306, China. Electronic address:
The widespread use of nano titanium dioxide (nano-TiO₂) poses ecological risks to marine ecosystems, especially when combined with ocean warming. However, most previous studies have only examined water-related exposures, leaving a gap in research on the impact of food transfer on organisms. In this work, the harmful impacts of nano-TiO on the Japanese swimming crab Charybdis japonica were studied through three scenarios: direct exposure (DE) of the crabs to warming and nano-TiO, indirect exposure (IE) via consumption of thick-shelled mussels Mytilus coruscus exposed to the same conditions, and combined exposure (CE), where crabs were directly subjected to warming and nano-TiO while feeding affected mussels.
View Article and Find Full Text PDFFASEB J
January 2025
Department of Radiology, C.J. Gorter MRI Center, Leiden University Medical Center, Leiden, The Netherlands.
Brown adipose tissue (BAT) is a metabolically highly active tissue that dissipates energy stored within its intracellular triglyceride droplets as heat. Others have previously utilized MRI to show that the fat fraction of human supraclavicular BAT (scBAT) decreases upon cold exposure, compared with baseline (i.e.
View Article and Find Full Text PDFNutrients
December 2024
Institute of Quality Standards and Testing Technology for Agro-Products of Chinese Academy of Agricultural Sciences, Beijing 100081, China.
Background/objectives: Polyphenols represent a new strategy of dietary intervention for heat stress regulation.
Methods: The metabolic and genetic effects of three heat stress-regulated mung bean polyphenols on mouse small intestinal epithelial Mode-k cells were investigated by metabolomics-transcriptomics correlation analysis at different heat stress levels.
Results: Lipid metabolism, energy metabolism, and nervous system pathways were the key metabolic regulatory pathways.
Foods
January 2025
Laboratory of Food Biotechnology and Foods for Special Dietary Uses, Federal State Budgetary Scientific Institution Federal Research Center of Nutrition, Biotechnology and Food Safety, 109240 Moscow, Russia.
The development of plant-based meat substitutes is imperative for reducing animal fat intake and promoting dietary diversification. However, the flavor profiles of these products frequently fall short of consumer expectations. This study sought to optimize the production process of meat flavorings for plant-based products using the Taguchi method.
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