Smart covalent organic networks (CONs) with “on-off-on” light-switchable pores for molecular separation

Development of the new-generation membranes for tunable molecular separation requires materials with abilities beyond strict separation. Stimuli response could remotely adjust the membrane selectivity. Azobenzene derivatives can be photo-switched between trans and cis isomers under ultraviolet or visible light. Here, the azobenzenes were implanted as light switches to bridge the flexible cyclen building blocks. The smart covalent organic network membranes fold and unfold as origami that can be photo-switched between on-state (large) and off-state (small) pores. The cis membranes with off state under ultraviolet (UV) light have higher dye rejection than trans membranes with on-state channels. By controlling the trans-to-cis azobenzene isomerization via UV/Vis light, the pore size can be remotely controlled at the molecular level and the solvent permeance and dye rejection can be dynamically tuned.

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Recent advances in biomimetic sensing technologies

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2009.0005 ◽

2009 ◽

Vol 367 (1893) ◽

pp. 1559-1569 ◽

Cited By ~ 20

Author(s):

E.A.C Johnson ◽

R.H.C Bonser ◽

G Jeronimidis

Keyword(s):

Mechanical Properties ◽

Molecular Level ◽

Building Blocks ◽

Biological Materials ◽

Science And Engineering ◽

Innovative Technologies ◽

Engineering Community ◽

Levels Of Organization ◽

New Generation ◽

Development Structure

The importance of biological materials has long been recognized from the molecular level to higher levels of organization. Whereas, in traditional engineering, hardness and stiffness are considered desirable properties in a material, biology makes considerable and advantageous use of softer, more pliable resources. The development, structure and mechanics of these materials are well documented and will not be covered here. The purpose of this paper is, however, to demonstrate the importance of such materials and, in particular, the functional structures they form. Using only a few simple building blocks, nature is able to develop a plethora of diverse materials, each with a very different set of mechanical properties and from which a seemingly impossibly large number of assorted structures are formed. There is little doubt that this is made possible by the fact that the majority of biological ‘materials’ or ‘structures’ are based on fibres and that these fibres provide opportunities for functional hierarchies. We show how these structures have inspired a new generation of innovative technologies in the science and engineering community. Particular attention is given to the use of insects as models for biomimetically inspired innovations.

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Riboflavin and UV-Light Based Pathogen Reduction: Extent and Consequence of DNA Damage at the Molecular Level

Photochemistry and Photobiology ◽

10.1562/2003-12-23-ra-036.1 ◽

2004 ◽

Vol 80 (1) ◽

pp. 15 ◽

Cited By ~ 138

Author(s):

Vijay Kumar ◽

Owen Lockerbie ◽

Shawn D. Keil ◽

Patrick H. Ruane ◽

Matthew S. Platz ◽

...

Keyword(s):

Dna Damage ◽

Molecular Level ◽

Uv Light ◽

Pathogen Reduction

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Visible-Light Activated [2+2] Photocycloaddition Reaction Enabled Identification of Carbon-Carbon Double Bonds Position Isomerism in Structural Lipidomics

10.26434/chemrxiv.11813475 ◽

2020 ◽

Author(s):

Guifang Feng ◽

Yanhong Hao ◽

Liang Wu ◽

Suming Chen

Keyword(s):

Visible Light ◽

Uv Light ◽

Practical Importance ◽

Side Reactions ◽

Potential Health ◽

Fundamental Interest ◽

Unsaturated Lipids ◽

Health Damage ◽

Global Identification ◽

Polyunsaturated Lipids

The photocycloaddition of olefins with carbonyls is of fundamental interest and practical importance in C=C bond location in unsaturated lipids. However, the traditional UV light activated [2+2] photocycloaddition reaction suffers side reactions and potential health damage. Here, we reported the first example of visible-light activated [2+2] photocycloaddition of anthraquinone with unsaturated lipids. This reaction showed great capability for locating the C=C bonds in various kinds of monounsaturated and polyunsaturated lipids by combining with tandem mass spectrometry (MS), such as fatty acids, phospholipids and glycerides. Based on this developed reaction, a workflow with liquid chromatography tandem MS method was developed for the global identification of unsaturated lipids in human serum, and 86 of monounsaturated and complicated polyunsaturated lipids were identified with definitive positions of C=C bonds. This approach provides new insights both on the photocycloaddition reactions and the structural lipidomics.

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Green Synthesis of ZnO/Dy/NiO Heterostructures for Enhanced Photocatalytic Applications

Journal of Photocatalysis ◽

10.2174/2665976x01666200214125616 ◽

2020 ◽

Vol 1 (1) ◽

pp. 30-36

Author(s):

Shubha Jayachamarajapura Pranesh ◽

Diwya Lanka

Keyword(s):

Visible Light ◽

Uv Light ◽

Combustion Method ◽

Hybrid Nanocomposites ◽

Synthetic Dyes ◽

Hybrid Nanostructure ◽

Wide Range ◽

Visible Light Active ◽

Textile Industries ◽

Photocatalytic Applications

Background: Textile industries discharge harmful synthetic dyes to nearby water sources. These colour effluents should be treated before discharge to reduce the toxicity caused by synthetic colours. Objective: To synthesize visible light active superstructures to reduce water pollution caused by textile industries. Methods: We have successfully synthesized ZnO/Dy/NiO hybrid nanocomposites using waste curd as fuel by a simple combustion method. The obtained material was able to reduce recombination and enhanced the photocatalytic degradation of organic pollutants. The as-synthesized material was characterized by XRD, absorption spectroscopy, FESEM, EDAX, etc. The obtained hybrid nanostructure was used as a photocatalyst for the degradation of methylene blue under sunlight, UV light as well as in dark. Comparative experiments were carried out with a variation of catalytic load, pH, dye concentrations, etc. for a better understanding of the performance of the catalyst at various conditions. Results and Conclusion: The ternary compound shows wide range of absorption by expanding absorption band both in UV and visible regions. ZnO/Dy/NiO hybrid nanocomposites performed well and showed uniqueness in the activity uder visible light.

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Stress-responsive properties of metallocenes in metallopolymers

Polymer Chemistry ◽

10.1039/d1py00311a ◽

2021 ◽

Author(s):

Ye Sha ◽

Hao Zhang ◽

Zhou Zhou ◽

Zhenyang Luo

Keyword(s):

Molecular Level ◽

Building Blocks ◽

Review Article ◽

Stress Responsiveness

This review article combines the field of metallopolymers and stress-responsiveness on a molecular level, namely, metallocenes, as emerging stress-responsive building blocks for materials.

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Molecular-Level Investigation of Cycloaliphatic Epoxidised Ionic Liquids as a New Generation of Monomers for Versatile Poly(Ionic Liquids)

Polymers ◽

10.3390/polym13091512 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1512

Author(s):

Baris Demir ◽

Gabriel Perli ◽

Kit-ying Chan ◽

Jannick Duchet-Rumeau ◽

Sébastien Livi

Keyword(s):

Ionic Liquids ◽

Molecular Level ◽

Computational Approach ◽

Polymer Materials ◽

Chemical Structures ◽

Cycloaliphatic Epoxy ◽

Polymer Models ◽

Mechanical Performances ◽

Dynamics Simulations ◽

New Generation

Recently, a new generation of polymerised ionic liquids with high thermal stability and good mechanical performances has been designed through novel and versatile cycloaliphatic epoxy-functionalised ionic liquids (CEILs). From these first promising results and unexplored chemical structures in terms of final properties of the PILs, a computational approach based on molecular dynamics simulations has been developed to generate polymer models and predict the thermo–mechanical properties (e.g., glass transition temperature and Young’s modulus) of experimentally investigated CEILs for producing multi-functional polymer materials. Here, a completely reproducible and reliable computational protocol is provided to design, test and tune poly(ionic liquids) based on epoxidised ionic liquid monomers for future multi-functional thermoset polymers.

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Emerging 2D/0D g-C3N4/SnO2 S-scheme photocatalyst: New generation architectural structure of heterojunctions toward visible-light-driven NO degradation

Environmental Pollution ◽

10.1016/j.envpol.2021.117510 ◽

2021 ◽

pp. 117510

Author(s):

Viet Van Pham ◽

Diem-Quynh Mai ◽

Dai-Phat Bui ◽

Tran Van Man ◽

Bicheng Zhu ◽

...

Keyword(s):

Visible Light ◽

Visible Light Driven ◽

New Generation

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Fluorinated azobenzenes as supramolecular halogen-bonding building blocks

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.15.197 ◽

2019 ◽

Vol 15 ◽

pp. 2013-2019 ◽

Cited By ~ 1

Author(s):

Esther Nieland ◽

Oliver Weingart ◽

Bernd M Schmidt

Keyword(s):

Solid State ◽

Dft Calculations ◽

Visible Light ◽

Half Life ◽

Photophysical Properties ◽

Bathochromic Shift ◽

Halogen Bonding ◽

Building Blocks ◽

Partial Overlap

ortho-Fluoroazobenzenes are a remarkable example of bistable photoswitches, addressable by visible light. Symmetrical, highly fluorinated azobenzenes bearing an iodine substituent in para-position were shown to be suitable supramolecular building blocks both in solution and in the solid state in combination with neutral halogen bonding acceptors, such as lutidines. Therefore, we investigate the photochemistry of a series of azobenzene photoswitches. Upon introduction of iodoethynyl groups, the halogen bonding donor properties are significantly strengthened in solution. However, the bathochromic shift of the π→π* band leads to a partial overlap with the n→π* band, making it slightly more difficult to address. The introduction of iodine substituents is furthermore accompanied with a diminishing thermal half-life. A series of three azobenzenes with different halogen bonding donor properties are discussed in relation to their changing photophysical properties, rationalized by DFT calculations.

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The Spectral Sensitivities of Single Cells in the Median Ocellus of Limulus

The Journal of General Physiology ◽

10.1085/jgp.54.5.636 ◽

1969 ◽

Vol 54 (5) ◽

pp. 636-649 ◽

Cited By ~ 23

Author(s):

John Nolte ◽

Joel E. Brown

Keyword(s):

Visible Light ◽

Spectral Sensitivity ◽

Uv Light ◽

Single Cells ◽

Chromatic Adaptation ◽

Sensitivity Curve ◽

Receptor Cells ◽

Intracellular Microelectrodes ◽

Median Ocellus ◽

Spectral Sensitivity Curve

The spectral sensitivities of single Limulus median ocellus photoreceptors have been determined from records of receptor potentials obtained using intracellular microelectrodes. One class of receptors, called UV cells (ultraviolet cells), depolarizes to near-UV light and is maximally sensitive at 360 nm; a Dartnall template fits the spectral sensitivity curve. A second class of receptors, called visible cells, depolarizes to visible light; the spectral sensitivity curve is fit by a Dartnall template with λmax at 530 nm. Dark-adapted UV cells are about 2 log units more sensitive than dark-adapted visible cells. UV cells respond with a small hyperpolarization to visible light and the spectral sensitivity curve for this hyperpolarization peaks at 525–550 nm. Visible cells respond with a small hyperpolarization to UV light, and the spectral sensitivity curve for this response peaks at 350–375 nm. Rarely, a double-peaked (360 and 530 nm) spectral sensitivity curve is obtained; two photopigments are involved, as revealed by chromatic adaptation experiments. Thus there may be a small third class of receptor cells containing two photopigments.

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