Chemically controlled pattern formation in self-oscillating elastic shells

Patterns and morphology develop in living systems such as embryos in response to chemical signals. To understand and exploit the interplay of chemical reactions with mechanical transformations, chemomechanical polymer systems have been synthesized by attaching chemicals into hydrogels. In this work, we design autonomous responsive elastic shells that undergo morphological changes induced by chemical reactions. We couple the local mechanical response of the gel with the chemical processes on the shell. This causes swelling and deswelling of the gel, generating diverse morphological changes, including periodic oscillations. We further introduce a mechanical instability and observe buckling–unbuckling dynamics with a response time delay. Moreover, we investigate the mechanical feedback on the chemical reaction and demonstrate the dynamic patterns triggered by an initial deformation. We show the chemical characteristics that account for the shell morphology and discuss the future designs for autonomous responsive materials.

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Reactions

10.1093/oso/9780199695126.001.0001 ◽

2011 ◽

Author(s):

Peter Atkins

Keyword(s):

Chemical Reactions ◽

Molecular Level ◽

Chemical Processes ◽

Chemical Formula ◽

Complex Processes ◽

Full Color ◽

Chemistry Textbooks ◽

Simple Chemical ◽

The Subject ◽

Solid Form

Illustrated with remarkable new full-color images--indeed, one or more on every page--and written by one of the world's leading authorities on the subject, Reactions offers a compact, pain-free tour of the inner workings of chemistry. Reactions begins with the chemical formula almost everyone knows--the formula for water, H2O--a molecule with an "almost laughably simple chemical composition." But Atkins shows that water is also rather miraculous--it is the only substance whose solid form is less dense than its liquid (hence ice floats in water)--and incredibly central to many chemical reactions, as it is an excellent solvent, being able to dissolve gases and many solids. Moreover, Atkins tells us that water is actually chemically aggressive, and can react with and destroy the compounds dissolved in it, and he shows us what happens at the molecular level when water turns to ice--and when it melts. Moving beyond water, Atkins slowly builds up a toolkit of basic chemical processes, including precipitation (perhaps the simplest of all chemical reactions), combustion, reduction, corrosion, electrolysis, and catalysis. He then shows how these fundamental tools can be brought together in more complex processes such as photosynthesis, radical polymerization, vision, enzyme control, and synthesis. Peter Atkins is the world-renowned author of numerous best-selling chemistry textbooks for students. In this crystal-clear, attractively illustrated, and insightful volume, he provides a fantastic introductory tour--in just a few hundred colorful and lively pages - for anyone with a passing or serious interest in chemistry.

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The priority of the heat production in a muscle twitch

Proceedings of the Royal Society of London Series B Biological Sciences ◽

10.1098/rspb.1958.0033 ◽

1958 ◽

Vol 148 (932) ◽

pp. 397-402 ◽

Cited By ~ 11

Keyword(s):

Chemical Reactions ◽

Heat Production ◽

Mechanical Response ◽

Substantial Part ◽

Hypertonic Solution ◽

Isotonic Solution ◽

Muscle Twitch ◽

Previous Conclusion

When a muscle has been soaked in a moderately hypertonic solution its mechanical response to a shock is delayed, but its heat production is almost normal and starts considerably earlier than its shortening. After a more hypertonic solution the mechanical response is abolished, but a substantial part of the heat production remains. These effects are rapidly reversed by soaking in a normal isotonic solution. They strengthen the previous conclusion that chemical reactions triggered by a stimulus precede the mechanical response.

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The chemical and physiological reactions of certain synthesised proteid-like substances. Preliminary communication

Proceedings of the Royal Society of London ◽

10.1098/rspl.1896.0053 ◽

1897 ◽

Vol 60 (359-367) ◽

pp. 337-349 ◽

Cited By ~ 1

Keyword(s):

Benzoic Acid ◽

Chemical Reactions ◽

Phosphorus Pentachloride ◽

Gaseous Ammonia ◽

Chemical Characteristics ◽

Physiological Action ◽

Preliminary Communication ◽

Pigmented Rabbits ◽

Physiological Reactions ◽

A Current

The experiments of Professor Grimaux, made more than ten years ago, have until recently attracted but little attention amongst English physiologists, although that investigator has synthesised a series of colloidal substances which, in their chemical characteristics, show striking similarities to proteids. Working alone, and in collaboration with Professor Halliburton, I have shown that three of the substances synthesised, viz., the "Colloids amidobenzoic A and B,” formed by the interaction of phosphorus pentachloride and meta-amido-benzoic acid at 125º C., according to the details described in Grimaux’s papers, and the “colloÏde aspartique” formed by the passage of a current of dry gaseous ammonia over solid aspartic anhydride heated to 125º C., not only give the leading chemical reactions of proteids, but when intravenously injected into dogs, cats, or pigmented rabbits, cause extensive intravascular coagulation of the blood, in a manner indistinguishable from the physiological action of nucleo-proteids.

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About Chemical Modifications of Finite Dimensional QED Models

Nonlinear Phenomena in Complex Systems ◽

10.33581/1561-4085-2021-24-3-230-241 ◽

2021 ◽

Vol 24 (3) ◽

pp. 230-241

Author(s):

Vitaliy Afanasyev ◽

Zheng Keli ◽

Alexei Kulagin ◽

Hui-hui Miao ◽

Yuri Ozhigov ◽

...

Keyword(s):

Chemical Reactions ◽

Quantum Interference ◽

Chemical Processes ◽

Long Term Results ◽

Quantum Master Equation ◽

Stationary States ◽

Optical Cavities ◽

Finite Dimensional ◽

Diatomic Systems

Suggestion of modifications of finite-dimensional quantum-electrodynamic (QED) models are proposed for interpreting chemical reactions in terms of artificial atoms and molecules on quantum dots placed in optical cavities. Moving both photons and atoms is possible between the cavities. Super dark states of diatomic systems are described, in which the motion of atoms between cavities is impossible due to quantum interference. Chemical processes with two level atoms and three level atoms with lambda spectrum are schematically modeled by solving the single quantum master equation with the Lindblad operators of photon leakage from the cavity and influx into it; association and dissociation reactions then differ only in the initial states. An example is given of the optical interpretation of the transition of an electron from atom to atom in terms of the multilevel Tavis-Cummings-Hubbard model with an estimate of the accuracy. Polyatomic chemical reactions are too complex for accurate modeling. Our method of rough interpretation helps to obtain their long-term results, for example, the form of stationary states of reagents, such as dark and super dark states.

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Characterization of Multi-Phase and Multi-Component Polymer Systems Using the Atomic Force Microscope

Microscopy and Microanalysis ◽

10.1017/s1431927600018134 ◽

1999 ◽

Vol 5 (S2) ◽

pp. 962-963

Author(s):

M. VanLandingham ◽

X. Gu ◽

D. Raghavan ◽

T. Nguyen

Keyword(s):

Energy Dissipation ◽

Atomic Force Microscope ◽

Mechanical Response ◽

Sample Surface ◽

Phase Changes ◽

Phase Imaging ◽

Polymer Systems ◽

Atomic Force ◽

Phase Images ◽

Multi Phase

Recent advances have been made on two fronts regarding the capability of the atomic force microscope (AFM) to characterize the mechanical response of polymers. Phase imaging with the AFM has emerged as a powerful technique, providing contrast enhancement of topographic features in some cases and, in other cases, revealing heterogeneities in the polymer microstructure that are not apparent from the topographic image. The enhanced contrast provided by phase images often allows for identification of different material constituents. However, while the phase changes of the oscillating probe are associated with energy dissipation between the probe tip and the sample surface, the relationship between this energy dissipation and the sample properties is not well understood.As the popularity of phase imaging has grown, the capability of the AFM to measure nanoscale indentation response of polymers has also been explored. Both techniques are ideal for the evaluation of multi-phase and multi-component polymer systems.

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Definitions of terms relating to reactions of polymers and to functional polymeric materials (IUPAC Recommendations 2003)

Pure and Applied Chemistry ◽

10.1351/pac200476040889 ◽

2004 ◽

Vol 76 (4) ◽

pp. 889-906 ◽

Cited By ~ 76

Author(s):

K. Horie ◽

Máximo Barón ◽

R. B. Fox ◽

J. He ◽

M. Hess ◽

...

Keyword(s):

Chemical Reactions ◽

Polymeric Materials ◽

Functional Polymers ◽

Polymer Systems ◽

The Third ◽

Polymer Reactions

The document defines the terms most commonly encountered in the field of polymer reactions and functional polymers. The scope has been limited to terms that are specific to polymer systems. The document is organized into three sections. The first defines the terms relating to reactions of polymers. Names of individual chemical reactions are omitted from the document, even in cases where the reactions are important in the field of polymer reactions. The second section defines the terms relating to polymer reactants and reactive polymeric materials. The third section defines the terms describing functional polymeric materials.

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Are the Fractionation Corrections Correct: Are the Isotopic Shifts for 14C/12C Ratios in Physical Processes and Chemical Reactions Really Twice Those for 13C/12C?

Radiocarbon ◽

10.1017/s003382220003914x ◽

2011 ◽

Vol 53 (4) ◽

pp. 691-704 ◽

Cited By ~ 14

Author(s):

John Southon

Keyword(s):

Chemical Reactions ◽

Isotopic Fractionation ◽

Theoretical Work ◽

Chemical Processes ◽

Physical Processes ◽

Isotopic Discrimination ◽

True Value ◽

A Value ◽

Isotopic Shifts ◽

Physical And Chemical

Conventional radiocarbon calculations correct for isotopic fractionation using an assumed value of 2.0 for the fractionation of 14C relative to 13C. In other words, isotopic discrimination in physical and chemical processes is assumed to cause relative shifts in 14C/12C ratios that are exactly double those of 13C/12C. This paper analyzes a 1984 experiment that produced a value for the fractionation ratio in photosynthesis of 2.3, which is used to this day by some researchers in the fields of hydrology and speleothem geochemistry. While the value of 2.3 is almost certainly incorrect, theoretical work suggests that the true value may indeed deviate from 2.0, which would have significant implications for 14C calculations.

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