Sulfonated polymerized liquid crystal nanoporous membranes for water purification

Reverse Osmosis (RO) for the desalination of saline water is associated with tremendous energy costs and low efficiency. Improvements in nanotechnology have led to the development of a variety of nanoporous membranes for water purification. Biomimetic membrane is an emerging new technology for water purification. Consequently, there is still much to study about the function and structure of these kinds of membranes. The purpose of this work was to determine which factors influence membrane performance. The focus was on those factors affecting membranes in pure water. Biomimetic membrane using MoS2 which has a higher rate of ion rejection and higher water permeability was studied through molecular dynamics simulations using reactive force fields (ReaxFF). The behaviour of the membrane before subjecting it to desalination was studied. The effect of water temperature, atmospheric pressure and membrane thickness on performance of membrane was studied. The permeability flux was calculated and compared in different conditions and the relation between these factors was revealed.

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The interaction of atoms and molecules with nanocapsules and hollow nanowires

Scientific Reports ◽

10.1038/s41598-020-72327-6 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Valentina A. Poteryaeva ◽

Michael A. Bubenchikov ◽

Alexey Michailovich Bubenchikov ◽

Alexandr Viktorovich Lun-Fu

Keyword(s):

Gas Separation ◽

Water Purification ◽

Chemical Properties ◽

Porous Membrane ◽

Nanoporous Membranes ◽

Carbon Spheres ◽

Atoms And Molecules ◽

Hollow Carbon ◽

Hollow Carbon Spheres ◽

And Chemical Properties

Abstract Nanoporous membranes are widely used in various fields, such as gas separation, water purification, catalytic processes, and the use of batteries in electrodes. Nowadays, hollow carbon spheres or nanowires are attracting attention of researchers and experimenters due to high adjustability of their mechanical and chemical properties. This makes it possible, among other things, to more accurately adjust permeability of membranes created from this material for various atoms and molecules, which ensures a good degree of gas separation. The mathematical simulation of gas separation via nanocapsule and hollow nanowire porous membrane is performed. Research has shown that such membranes are able to separate He/$$\text{CH}_4$$ CH 4 /$$\text{H}_2$$ H 2 /$$\text{N}_2$$ N 2 gas mixtures.

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Recent Advances in Nanoporous Membranes for Water Purification

Nanomaterials ◽

10.3390/nano8020065 ◽

2018 ◽

Vol 8 (2) ◽

pp. 65 ◽

Cited By ~ 49

Author(s):

Zhuqing Wang ◽

Aiguo Wu ◽

Lucio Colombi Ciacchi ◽

Gang Wei

Keyword(s):

Water Purification ◽

Nanoporous Membranes ◽

Recent Advances

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Freeze-fracture TEM of the helical smectic A* phase

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010012179x ◽

1992 ◽

Vol 50 (1) ◽

pp. 278-279

Author(s):

K.J. Ihn ◽

R. Pindak ◽

J. A. N. Zasadzinski

Keyword(s):

Liquid Crystal ◽

Grain Boundary ◽

Grain Boundaries ◽

Freeze Fracture ◽

Smectic Phase ◽

Layer Spacing ◽

Screw Dislocations ◽

Smectic A ◽

Smectic Phases ◽

Discrete Amount

A new liquid crystal (called the smectic-A* phase) that combines cholesteric twist and smectic layering was a surprise as smectic phases preclude twist distortions. However, the twist grain boundary (TGB) model of Renn and Lubensky predicted a defect-mediated smectic phase that incorporates cholesteric twist by a lattice of screw dislocations. The TGB model for the liquid crystal analog of the Abrikosov phase of superconductors consists of regularly spaced grain boundaries of screw dislocations, parallel to each other within the grain boundary, but rotated by a fixed angle with respect to adjacent grain boundaries. The dislocations divide the layers into blocks which rotate by a discrete amount, Δθ, given by the ratio of the layer spacing, d, to the distance between grain boundaries, lb; Δθ ≈ d/lb (Fig. 1).

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Attractive mode force microscopy of chiral liquid crystal surfaces

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100121740 ◽

1992 ◽

Vol 50 (1) ◽

pp. 268-269

Author(s):

B.D. Terris ◽

R. J. Twieg ◽

C. Nguyen ◽

G. Sigaud ◽

H. T. Nguyen

Keyword(s):

Liquid Crystal ◽

Crystal Surfaces ◽

Free Surfaces ◽

Control Range ◽

Force Microscopy ◽

Liquid Crystal Films ◽

Chiral Liquid Crystal ◽

Crystal Films ◽

Electrostatic Charging ◽

And Shifts

We have used a force microscope in the attractive, or noncontact, mode to image a variety of surfaces. In this mode, the microscope tip is oscillated near its resonant frequency and shifts in this frequency due to changes in the surface-tip force gradient are detected. We have used this technique in a variety of applications to polymers, including electrostatic charging, phase separation of ionomer surfaces, and crazing of glassy films.Most recently, we have applied the force microscope to imaging the free surfaces of chiral liquid crystal films. The compounds used (Table 1) have been chosen for their polymorphic variety of fluid mesophases, all of which exist within the temperature control range of our force microscope.

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