Effect of a weak electric field on THF hydrate formation: Induction time and morphology

Abstract This study investigates the effects of types of impellers and baffles on methane hydrate formation. Induction time, water conversion to hydrates (hydrate yield), hydrate formation rate and hydrate productivity are components that were estimated. The initial hydrate formation rate is generally higher with the use of Ruston turbine (RT) with higher values 28.93 × 10−8 mol/s in RT/RT with full baffle (FB) experiment, but the decline rate of hydrate formation was also high compared to up-pumping pitched blade turbine (PBTU). Power consumption is higher also in RT/RT and PBT/RT with higher value 392,000 W in PBT/RT with no baffle (NB) experiment compared to PBT/PBT and RT/PBT experiments respectively. Induction time values are higher in RT/RT experiments compared to PBT/PBT ones. Hydrate yield is always smaller when there is no baffle in all four groups of experiments while the higher values exist in experiments with full baffle. It should be noticed that PBT is the same with PBTU, since all experiments with mixed flow have upward trending.

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Deterministic Tools to Estimate Induction Time for Methane Hydrate Formation in the Presence of Luvicap 55 W Solutions

Journal of Molecular Liquids ◽

10.1016/j.molliq.2021.118374 ◽

2021 ◽

pp. 118374

Author(s):

Marziyeh Zare ◽

Sohrab Zendehboudi ◽

Majid Abedinzadegan Abdi

Keyword(s):

Induction Time ◽

Methane Hydrate ◽

Hydrate Formation

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Induction time of hydrate formation in a flow loop

Theoretical Foundations of Chemical Engineering ◽

10.1134/s0040579510020119 ◽

2010 ◽

Vol 44 (2) ◽

pp. 201-205 ◽

Cited By ~ 7

Author(s):

M. Sarshar ◽

F. Esmaeilzadeh ◽

J. Fathikalajahi

Keyword(s):

Induction Time ◽

Hydrate Formation ◽

Flow Loop

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ELECTRO-OPTICAL SWITCHING OF THE MAIN OPTICAL AXIS OF A FERROELECTRIC LIQUID CRYSTAL SPIRAL NANOSTRUCTUREIN A PLANAR-ORIENTED DISPLAY CELL

Doklady BGUIR ◽

10.35596/1729-7648-2019-125-7-21-27 ◽

2019 ◽

pp. 21-27

Author(s):

E. P. Pozhidaev ◽

T. P. Tkachenko ◽

A. V. Kuznetsov ◽

I. N. Kompanets

Keyword(s):

Liquid Crystal ◽

Electric Field ◽

Optical Switching ◽

Optical Axis ◽

Modulation Frequency ◽

Light Transmittance ◽

Weak Electric Field ◽

Ferroelectric Liquid Crystal ◽

Light Modulation ◽

Small Pitch

In a known display cell with the nematic liquid crystal (NLC) and interdigital electrodes on one of the glass substrates, the “In-Plane Switching” (IPS) mode is implemented, in which the NLC main optical axis reorients in a plane parallel to substrates, providing the most correct color reproduction at different angles view, up to 178 ° horizontally and vertically. Unfortunately, the creation of interdigital metal electrodes complicates and increases the technological process cost and causes a decrease in image contrast. At the same time, experimental results and calculations based on classical electro-optics of crystals indicate that electrooptical switching in the IPS mode is a natural and intrinsic feature of a conventional (with continuous electrodes) display cell with a planar-oriented layer of the ferroelectric liquid crystal (FLC), in which the effect of the deformed (by the electric field) helix FLC nanostructure is realized (DHF effect). In such a cell, the reorientation of the main optical axis under the influence of a weak electric field also occurs in the substrate plane if the FLC has a small pitch (about 100 nm or less) and a large tilt angle of molecules in the layer (about 38 ° or more). The dependences of the FLC cell light transmittance measured in this work, confirmed the achievement of the IPS electro-optical mode in the DHF FLC cell; moreover, the light modulation frequency was 1 kHz. Thus, while maintaining all the advantages of the IPS mode known in NLC, its implementation in FLC allows additionally obtaining technological advantages and multiple increase in modulation frequency.

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Two Types of Oscillations of the Holstein Polaron Uniformly Moving Along a Polynucleotide Chain in a Constant Electric Field

Математическая биология и биоинформатика ◽

10.17537/2019.14.477 ◽

2019 ◽

Vol 14 (2) ◽

pp. 477-487

Author(s):

A.N. Korshunova ◽

V.D. Lakhno

Keyword(s):

Electric Field ◽

Field Intensity ◽

Electric Field Intensity ◽

Constant Electric Field ◽

Weak Electric Field ◽

Uniform Motion ◽

Main Task ◽

Charge Motion ◽

Bloch Oscillations ◽

One Dimensional

In connection with the development of molecular nanobioelectronics, the main task of which is the construction of electronic devices based on biological molecules, the problems of charge transfer in such extended molecules as DNA are of increasing interest. The relevance of studying the charges motion in one-dimensional molecular chains is primarily associated with the possibility of using these chains as wires in nanoelectronic devices. Current carriers in one-dimensional chains are self-trapped electronic states, which have the form of polaron formations. In this paper we investigate the motion of the Holstein polaron in the process of its uniform motion along the chain in a constant electric field. It is known that during uniform motion along the chain in a weak electric field, the polaron experiences small oscillations of its shape. These oscillations are associated with the discreteness of the chain and are due to the presence of the Peierls-Nabarro potential in the discrete chain. Previous investigations have shown that for certain parameters of the chain, there is the possibility of uniform charge motion in a constant electric field over very large distances. The charge motion with a constant velocity is possible for small values of the electric field intensity. With an increase in the electric field intensity, the charge goes into an oscillatory regime of motion with Bloch oscillations. The calculations performed in this work showed that the elements of Bloch oscillations also appear during stationary motion of the polaron along the chain. Thus, it is shown that the Holstein polaron, uniformly moving along the chain in a constant electric field, experiences not only Peierls-Nabarro oscillations, but also low-amplitude oscillations with a Bloch period.

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