scholarly journals Effects of structural parameters on water film properties of transpiring wall reactor

2021 ◽  
Author(s):  
Donghai Xu ◽  
Peng Feng ◽  
Yang Wang ◽  
Wanpeng Yang ◽  
Yu Wang ◽  
...  
Keyword(s):  
Water Oxidation ◽  
Structural Parameters ◽  
Water Film ◽  
Internal Surface ◽  
Water Layer ◽  
Film Properties ◽  
Reactor Length ◽  
Inner Diameter ◽  
Experimental Values ◽  
Coverage Rates

Reactor corrosion and salt deposition problems severely restrict the industrialization of supercritical water oxidation. Transpiring wall reactor can effectively weaken these two problems through a protective water film formed on its internal surface. In this work, the effects of key structural parameters on water film properties of transpiring wall reactor were explored by numerical simulation, and established models were validated by comparing simulation and experimental values. The results show that transpiration water layer, transpiring wall porosity and inner diameter hardly affected organic matter degradation. Increasing transpiration water layer and transpiring wall porosity reduced reactor center temperatures in the middle and lower zones of the reactor. Increasing transpiration water layer, transpiring wall porosity and inner diameter decreased water film temperatures but increased water film coverage rates. Increasing reactor length affected slightly on the volume of the upper supercritical oxidation zone but enlarged the subcritical zone.

scholarly journals Effects of structural parameters on water film properties of transpiring wall reactor

AIChE Journal ◽  
2021 ◽  
Author(s):  
Donghai Xu ◽  
Peng Feng ◽  
Yang Wang ◽  
Wanpeng Yang ◽  
Yu Wang ◽  
...  
Keyword(s):  
Structural Parameters ◽  
Water Film ◽  
Film Properties

scholarly journals Insights into the interactions and dynamics of a DES formed by phenyl propionic acid and choline chloride

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Parisa Jahanbakhsh Bonab ◽  
Alireza Rastkar Ebrahimzadeh ◽  
Jaber Jahanbin Sardroodi
Keyword(s):  
Diffusion Coefficient ◽  
Liquid Phase ◽  
Propionic Acid ◽  
Structural Parameters ◽  
Choline Chloride ◽  
Self Diffusion ◽  
Phenyl Propionic Acid ◽  
Donor And Acceptor ◽  
Experimental Values ◽  
Self Diffusion Coefficient

AbstractDeep eutectic solvents (DESs) have received much attention in modern green chemistry as inexpensive and easy to handle analogous ionic liquids. This work employed molecular dynamics techniques to investigate the structure and dynamics of a DES system composed of choline chloride and phenyl propionic acid as a hydrogen bond donor and acceptor, respectively. Dynamical parameters such as mean square displacement, liquid phase self-diffusion coefficient and viscosity are calculated at the pressure of 0.1 MPa and temperatures 293, 321 and 400 K. The system size effect on the self-diffusion coefficient of DES species was also examined. Structural parameters such as liquid phase densities, hydrogen bonds, molecular dipole moment of species, and radial and spatial distribution functions (RDF and SDF) were investigated. The viscosity of the studied system was compared with the experimental values recently reported in the literature. A good agreement was observed between simulated and experimental values. The electrostatic and van der Waals nonbonding interaction energies between species were also evaluated and interpreted in terms of temperature. These investigations could play a vital role in the future development of these designer solvents.

scholarly journals Moisture Induced Degradation of Porous Low-k Materials

2006 ◽  
Vol 914 ◽  
Author(s):  
Mikhail Baklanov ◽  
David O'Dwyer ◽  
Adam M Urbanowicz ◽  
Quoc Toan Le ◽  
Steven Demuynck ◽  
...  
Keyword(s):  
Water Film ◽  
Internal Surface ◽  
Hydrophobic Surface ◽  
Adsorbed Water ◽  
Bulk Water ◽  
Oh Groups ◽  
Film Bulk ◽  
Low K

AbstractInteraction of moisture with porous low-k films is evaluated by using in situ ellipsometry setup. The adsorbed water amount is calculated from change of refractive index measured during the adsorption. Pristine low-k films reversibly adsorb 2 - 5% of water that reflects presence of constitutive hydrophilic centrums. Plasma and thermal treatments increase the number of hydrophilic centrums. Once the amount of these centrums has reached a certain critical value sufficient to form a continuous water film, bulk water condensation is observed. Change of properties during the water adsorption in the damaged films is not fully reversible. Each additional adsorption cycle increases the dielectric function of the film because of decreasing porosity, increasing skeleton density and shrinkage. The pressure corresponding to the bulk condensation allows us to calculate internal contact angle (internal surface energy) of low-k materials. The water molecules adsorbed on separate OH groups play the role of a catalyst that hydrolyses the siloxane bridges initially present on hydrophobic surface.

scholarly journals First principles study of structure, electronic and optical properties of Y3Fe5O12 in cubic and trigonal phases

2015 ◽  
Vol 33 (1) ◽  
pp. 169-174 ◽  
Author(s):  
Shen Tao ◽  
Hu Chao ◽  
Dai Hailong ◽  
Yang Wenlong ◽  
Liu Hongchen ◽  
...  
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Energy Loss ◽  
First Principles ◽  
Structural Parameters ◽  
Band Gaps ◽  
First Principles Calculations ◽  
Electronic And Optical Properties ◽  
Direct Band ◽  
Experimental Values

AbstractFirst principles calculations have been performed to investigate the structure, electronic and optical properties of Y3Fe5O12. Both the cubic and trigonal phases have been considered in our calculation. The calculated structural parameters are slightly larger than the experimental values. The band structures show that Y3Fe5O12 in cubic and trigonal phases have direct band gaps of 0.65 and 0.17 eV. The calculations of dielectric function, absorption, extinction coefficient, refractive index, energy loss function and reflectivity are presented.

A novel multiaxial three-dimensional woven preform: Process and structure

2017 ◽  
Vol 37 (4) ◽  
pp. 247-266 ◽  
Author(s):  
Xinmiao Wang ◽  
Li Chen ◽  
Junshan Wang ◽  
Xintao Li ◽  
Zhongwei Zhang
Keyword(s):  
Cross Sections ◽  
Structural Parameters ◽  
Three Dimensional ◽  
Woven Composite ◽  
Cell Geometry ◽  
Geometry Model ◽  
End Use ◽  
Experimental Values ◽  
Composite Samples ◽  
Good Agreement

A novel multiaxial three-dimensional woven preform and the weaving technique have been developed in this study. The preform exhibits remarkable designs, which is formed by multiple layers of different yarn sets, including bias (+bias/−bias), warp, and filling, and all layers are locked by Z-yarns These layers are arranged in a rectangular fashion and the layer number and the position of bias layer can be determined by the end-use requirements. A weaving process and machine are proposed to produce the preform. The weaving technique enables the insertion of many warp layers between two opposite bias layers. The microstructure of the preform was also studied. Microscopic evidence of the microstructure reveals that the cross-sections of Z-yarn are variable along its central axis due to the lateral compression forces of adjacent yarns from different directions. On the basis of microscopic observation, a unit cell geometry model of multiaxial three-dimensional woven preform is established, and a good agreement has been obtained between the theoretical and experimental values of the structural parameters of woven composite samples.

scholarly journals Determination of nanostructure of liposomes containing two model drugs by X-ray scattering from a synchrotron source

2013 ◽  
Vol 20 (5) ◽  
pp. 721-728 ◽  
Author(s):  
Alexandr Nasedkin ◽  
Jan Davidsson ◽  
Mont Kumpugdee-Vollrath
Keyword(s):  
Experimental Data ◽  
Small Angle ◽  
Structural Parameters ◽  
Water Layer ◽  
Synchrotron Source ◽  
X Ray ◽  
X Ray Scattering ◽  
Extract Information ◽  
Ray Scattering

Small-angle X-ray scattering has been employed to study how the introduction of paracetamol and acetylsalicylic acid into a liposome bilayer system affects the system's nanostructure. An X-ray scattering model, developed for multilamellar liposome systems [Pabstet al.(2000),Phys. Rev. E,62, 4000–4009], has been used to fit the experimental data and to extract information on how structural parameters, such as the number and thickness of the bilayers of the liposomes, thickness of the water layer in between the bilayers, size and volume of the head and tail groups, are affected by the drugs and their concentration. Even though the experimental data reveal a complicated picture of the drug–bilayer interaction, they clearly show a correlation between nanostructure, drug and concentration in some aspects. The localization of the drugs in the bilayers is discussed.

Structural, electronic and optical properties of LiNbO3 using GGA-PBE and TB-mBJ functionals: A DFT study

2018 ◽  
Vol 32 (14) ◽  
pp. 1850168 ◽  
Author(s):  
M. Arshad Javid ◽  
Zafar Ullah Khan ◽  
Zahid Mehmood ◽  
Azeem Nabi ◽  
Fayyaz Hussain ◽  
...  
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Lithium Niobate ◽  
Dielectric Function ◽  
Lithium Niobate Crystal ◽  
Structural Parameters ◽  
Dft Method ◽  
Bandgap Energy ◽  
Electronic And Optical Properties ◽  
Experimental Values

In the present work, first-principles calculations were performed to obtain the structural, electronic and optical properties of lithium niobate crystal using two exchange-correlation functionals (GGA-PBE and TB-mBJ). The calculated structural parameters were very close to the experimental values. TB-mBJ functional was found to be good when compared to LDA and GGA functionals in case of bandgap energy of 3.715 eV of lithium niobate. It was observed that the upper valence and lower conduction bands consist mainly the O-2p and Nb-4[Formula: see text] states, respectively. Furthermore, calculations for real and imaginary parts of frequency-dependent dielectric function [Formula: see text] of lithium niobate crystal were performed using TD-DFT method. The ordinary refractive index n[Formula: see text], extraordinary refractive index n[Formula: see text], its birefringence and absorption peaks in imaginary dielectric function [Formula: see text] were also calculated.

scholarly journals The Effect of Adsorbed Volatile Organic Compounds on an Ultrathin Water Film Measurement

2020 ◽  
Vol 10 (17) ◽  
pp. 5981 ◽  
Author(s):  
Shahab Bayani Ahangar ◽  
Chan Ho Jeong ◽  
Fei Long ◽  
Jeffrey S. Allen ◽  
Seong Hyuk Lee ◽  
...  
Keyword(s):  
Volatile Organic Compounds ◽  
Surface Treatment ◽  
Organic Compounds ◽  
High Speed ◽  
Water Film ◽  
Water Layer ◽  
Dropwise Condensation ◽  
Air Plasma ◽  
High Speed Imaging ◽  
Volatile Organic

Using surface plasmon resonance imaging (SPRi), we have recently shown for the first time the existence of a monolayer water film between droplets during dropwise condensation. This study examines the effect of adsorbed volatile organic compounds (VOCs) on the ultrathin film measurement using SPRi. Further, the work presents the proper surface-treatment process that enables measurements of the ultrathin water layer during high-speed imaging of dropwise condensation at 3000 frame per second. In this study, two methods were applied for cleaning the surface (gold-coated glass)—(1) standard cleaning procedure (SCP) using acetone, isopropyl alcohol, and deionized water and (2) SCP followed by air plasma cleaning. This work discusses the effect of the cleaning procedures on surface roughness, contact angle, and surface chemistry using atomic force microscopy, optical microscopy, and an X-ray photoelectron spectroscope meter. The results showed that SCP before the SPRi is a proper surface-treatment method. The effect of adsorbed VOCs during dropwise condensation on a surface treated with SCP was measured to be 0.0025 (reflectivity unit), which was 70% smaller than the reflectance associated with a monolayer water film. The results of this work confirm a monolayer water film observation during the dropwise condensation, which has been reported before.

scholarly journals Subglacial swamps

2014 ◽  
Vol 470 (2171) ◽  
pp. 20140340 ◽  
Author(s):  
T. M. Kyrke-Smith ◽  
A. C. Fowler
Keyword(s):  
Sediment Transport ◽  
Ice Sheets ◽  
Water Film ◽  
Water Layer ◽  
Sediment Layer ◽  
Instability Mechanism ◽  
Ice Streams ◽  
Water And Sediment ◽  
Fundamental Understanding ◽  
Ice Water

The existence of both water and sediment at the bed of ice streams is well documented, but there is a lack of fundamental understanding about the mechanisms of ice, water and sediment interaction. We pose a model to describe subglacial water flow below ice sheets, in the presence of a deformable sediment layer. Water flows in a rough-bedded film; the ice is supported by larger clasts, but there is a millimetric water layer submerging the smaller particles. Partial differential equations describing the water film are derived from a description of the dynamics of ice, water and mobile sediment. We assume that sediment transport is possible, either as fluvial bedload, but more significantly by ice-driven shearing and by internal squeezing. This provides an instability mechanism for rivulet formation; in the model, downstream sediment transport is compensated by lateral squeezing of till towards the incipient streams. We show that the model predicts the formation of shallow, swamp-like streams, with a typical depth of the order of centimetres. The swamps are stable features, typically with a width of the order of tens to hundreds of metres.

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