Dry Ice Quench
Dry Ice Quench - Related Videos
10:57
Quenching and Boiling
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2023
Source: Alexander S Rattner, Sanjay Adhikari, and Mahdi Nabil; Department of Mechanical and Nuclear Engineering, The Pennsylvania State University, University Park, PA Controlled heating followed by rapid cooling is an important element of many materials processing applications. This heat-treating procedure can increase material hardness, which is important for cutting tools or surfaces in high wear environments. The rapid cooling stage is called quenching, and is often performed by immersing...
08:07
Sample Preparation for Single Cell Mass Spectrometry Metabolomics Studies: Combined Cell Washing, Quenching, Drying, and Storage
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Cited by 1 •
2025
This protocol aims to preserve cell metabolites for single-cell mass spectrometry (SCMS) by combining volatile salt solution washing, rapid liquid nitrogen quenching, freeze-drying, and −8 °C storage. It demonstrates that liquid nitrogen quenching is essential for maintaining metabolite profiles, while prolonged cold storage should be minimized to prevent metabolic alterations.
07:47
Anti-virulent Disruption of Pathogenic Biofilms using Engineered Quorum-quenching Lactonases
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Cited by 7 •
2016
Quorum-quenching enzymes are anti-virulent and anti-bacterial options that can mitigate pathogenesis without risk of incurring resistance, by preventing the expression of virulence factors and genes associated with antibiotic resistance and biofilm formation. In this study, we report a method that demonstrates the efficacy of quorum-quenching enzymes in bacterial biofilm disruption.
08:58
Cerebral Blood Oxygenation Measurement Based on Oxygen-dependent Quenching of Phosphorescence
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Cited by 28 •
2011
We present an experimental procedure for measuring the partial pressure of oxygen (pO2) in cerebral vasculature based on oxygen-dependent quenching of phosphorescence. Animal preparation and imaging procedures were outlined for both large field of view CCD-based imaging of pO2 in rats and 2-photon excitation based imaging of pO2 in mice.
01:30
Dry Friction
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2023
Dry friction occurs between two solid surfaces in contact as they attempt to move relative to one another. In daily life, dry friction is encountered in various forms, such as when walking on the ground, sliding an object across a table, or rubbing hands together. Despite its ubiquity, the underlying mechanisms behind dry friction are not readily visible. To illustrate this concept, imagine a wooden crate resting on a rough, non-uniform horizontal surface. When an external force is applied to...
FAQs
Sublimation changes solid carbon dioxide directly into a gas while absorbing heat from the surrounding reaction mixture. This heat uptake produces rapid cooling, which can limit temperature excursions and help preserve sensitive products or intermediates. Because the cooling is intense, the technique requires controlled addition to prevent excessive bubbling or abrupt thermal changes in the mixture.
Carbon dioxide reacts with nucleophilic organometallic species, including organolithium and Grignard reagents, to form carboxylate salts. Subsequent acidic workup converts those salts into carboxylic acids. This transformation gives the quench an analytical role as well as a cooling function, because the resulting acid can provide an identifiable product from the reactive organometallic material.
Sublimation can generate vigorous bubbling while rapidly lowering the mixture temperature. If the evolving carbon dioxide cannot escape, gas production may contribute to pressure buildup. These effects make addition rate and ventilation important experimental variables rather than minor handling details. Managing them helps maintain control of the reaction mixture and reduces hazards associated with rapid gas evolution and extreme cooling.
A practical sequence is to introduce solid carbon dioxide carefully into the reactive mixture, use its sublimation to cool and terminate the reaction, and then perform acidic workup when conversion of organometallic-derived carboxylate salts is desired. The process should be conducted with adequate ventilation and attention to bubbling, temperature changes, and possible pressure buildup throughout the quench.
This approach is useful when a reaction must be stopped quickly, especially if it is exothermic or contains a reactive intermediate that should be preserved. Rapid heat removal can help control the mixture while the carbon dioxide also consumes nucleophilic organometallic species. Thus, the method combines reaction termination, temperature control, and, in suitable cases, chemical trapping.
For organolithium or Grignard chemistry, carbon dioxide converts the reactive species into carboxylate salts. Acidic workup then produces carboxylic acids, which serve as identifiable products. This outcome can reveal that the organometallic intermediate was present and successfully trapped, extending the quench beyond simple deactivation of the original reactive mixture.
Careful addition and effective ventilation are essential. Solid carbon dioxide can sublime quickly, causing vigorous bubbling and generating gas, while the mixture may reach very low temperatures. The setup must therefore accommodate gas release without pressure buildup, and the operator should control the addition rather than introducing the entire cooling agent without regard to the mixture’s response.