Interfacial Tension of the Methane-Normal Heptane System

1970 ◽  
Vol 10 (04) ◽  
pp. 327-327 ◽  
Author(s):  
H.G. Warren ◽  
E.W. Hough
Keyword(s):  
Interfacial Tension ◽  
Pressure Range ◽  
American Chemical Society ◽  
Chemical Society ◽  
Phase System ◽  
Two Phase ◽  
Drop Method ◽  
Direct Measurements ◽  
Experimental Values ◽  
Society Research

The interfacial tension values for the methane-n heptane two-phase system were determined by the pendeant-drop method on eight isotherms from 100 degrees pendeant-drop method on eight isotherms from 100 degrees to 310 degrees F. The pressure range was from 215 to 3,415 psia. Direct measurements of the maximum and minimum drop diameters were made. The tables of Winkel and the density difference data of Reamer et al. were used to calculate experimental values of interfacial tension. The experimental data varied from 16.64 dynes/cm at 217 psia at 100 degrees F to 0.081 dynes/cm at 3,415 psia at 130 degrees F. The smooth data is given in Table 1. Fig. 1 is a plot of smoothed data at 0.1, 1.0, 5.0 and 10.0 dynes/cm over the range of 100 degrees to 310 degrees F and 0 to 3,618 psia. The dashed lines are extrapolation of the data. A correlation of these data along with other hydrocarbon systems has been published. The data are taken from the PhD dissertation of one of the authors. The supplement of the American Chemical Society Research Fund Grant No. 635-A is gratefully acknowledged. TABLE 1 - INTERFACIAL TENSION OF THE METHANE - NORMAL HEPTANE SYSTEM SMOOTHED DATA Interfacial Tension (dynes/cm) Pressure Pressure psia 100 F 130 F 160F 190 F 220 F 250 F 280 F 310 F psia 100 F 130 F 160F 190 F 220 F 250 F 280 F 310 F 400 14.88 13.75 12.50 11.28 9.97 8.83 7.74 6.60800 11.33 10.60 9.88 8.96 7.96 6.98 6.07 5.111,200 8.50 8.00 7.55 6.88 6.18 5.32 4.55 3.711,600 6.16 5.85 5.53 5.04 4.54 3.80 3.16 2.482,000 4.21 4.06 3.83 3.47 3.04 0.45 1.90 1.352,200 3.35 3.83 3.47 3.04 2.37 1.85 1.39 0.872,400 2.57 2.50 2.36 2.13 1.76 1.30 0.91 0.472,600 1.85 1.82 1.73 1.54 1.23 0.83 0.50 0.132,800 1.22 1.22 1.15 1.00 0.74 0.41 0.17 2709*3,000 0.73 0.73 0.67 0.56 0.34 0.13 2927*3,100 0.53 0.53 0.47 0.37 0.19 0.033,200 0.35 0.35 0.31 0.23 0.07 3122*3,300 0.22 0.22 0.19 0.12 3298*3,400 0.13 0.13 0.10 0.033,500 0.06 0.02 3549*3,600 3606* 3618* *Critical pressure at temperature. P. 227

Microfluidic generation of aqueous two-phase system (ATPS) droplets by controlled pulsating inlet pressures

Lab on a Chip ◽  
2015 ◽  
Vol 15 (11) ◽  
pp. 2437-2444 ◽  
Author(s):  
Byeong-Ui Moon ◽  
Steven G. Jones ◽  
Dae Kun Hwang ◽  
Scott S. H. Tsai
Keyword(s):  
Interfacial Tension ◽  
Phase System ◽  
Flow Focusing ◽  
Two Phase ◽  
Aqueous Two Phase System ◽  
Microfluidic Flow ◽  
Aqueous Two Phase Systems ◽  
Phase Systems ◽  
Ultralow Interfacial Tension

Simple microfluidic flow focusing generation of droplets from ultralow interfacial tension aqueous two phase systems (ATPS).

Enhanced Low-Pressure Pneumatic Conveyance Using Swirl

2010 ◽  
Author(s):  
Rodrigo Escandon ◽  
Randall D. Manteufel ◽  
Q. Ken Su
Keyword(s):  
Vertical Section ◽  
Experimental System ◽  
Low Pressure ◽  
Phase System ◽  
Pneumatic Conveying ◽  
Two Phase ◽  
Before And After ◽  
Pneumatic Conveyance ◽  
Experimental Values

Two designs for swirl amplification have been considered for pneumatic conveyance in vertical pipes. Both designs have been experimentally evaluated in order to predict their capability. The designs have been compared to other methods of amplification or swirl generation. The motivation for the swirl in pneumatic conveyance is to minimize axial velocity by using multiple swirl amplifications to enhance the transportation for long distances. In this experimental evaluation two swirl amplifiers are considered. The evaluations are done by determining the static pressures before and after the swirl amplifier in the vertical section of an experimental system. This difference in pressure points allowed the determination of length of decay, which is the distance in which this two-phase system travels before a reduction in radial velocity. In the amplifiers, compressed air at two pressures was used for the purpose of creating a low pressure pneumatic conveying system. It is determined that when using these amplifications in the air boost, longer lengths of decay can be achieved in comparison to a no swirl system. This meant that the products transportation could be enhanced due to the addition of the swirl amplifiers. The experimental values were used to compare both designs. The more productive one was determined by its length of decay. As well as estimating the maximum obtainable distances for both swirl amplifiers at each particular amplification.

Water-head-driven microfluidic oscillators for autonomous control of periodic flows and generation of aqueous two-phase system droplets

Lab on a Chip ◽  
2017 ◽  
Vol 17 (2) ◽  
pp. 286-292 ◽  
Author(s):  
Van Bac Dang ◽  
Sung-Jin Kim
Keyword(s):  
Interfacial Tension ◽  
Autonomous Control ◽  
Phase System ◽  
Two Phase ◽  
Aqueous Two Phase System ◽  
Periodic Flows ◽  
Water Head ◽  
Low Interfacial Tension

This paper presents the mechanism of a water-head-driven oscillator and shows the generation of droplets with low interfacial tension.

scholarly journals Water-in-water droplets by passive microfluidic flow focusing

2021 ◽  
Author(s):  
Byeong-Ui Moon ◽  
Niki Abbasi ◽  
Steven G. Jones ◽  
Dae Kun Hwang ◽  
Scott S. H. Tsai
Keyword(s):  
Interfacial Tension ◽  
Microfluidic System ◽  
Column Height ◽  
Phase System ◽  
Flow Focusing ◽  
Two Phase ◽  
Passive Flow ◽  
Microfluidic Flow ◽  
Droplet Production ◽  
Order Of Magnitude

We present a simple microfluidic system that generates water-in-water, aqueous two phase system (ATPS) droplets, by passive flow focusing. ATPS droplet formation is achieved by applying weak hydrostatic pressures, with liquid-filled pipette tips as fluid columns at the inlets, to introduce low speed flows to the flow focusing junction. To control the size of the droplets, we systematically vary the interfacial tension and viscosity of the ATPS fluids, and adjust the fluid column height at the fluid inlets. The size of the droplets scales with a power-law of the ratio of viscous stresses in the two ATPS phases. Overall, we find a drop size coefficient of variation (CV; i.e. polydispersity) of about 10 %. We also find that when drops form very close to the flow focusing junction, the drops have CV of less than 1 %. Our droplet generation method is easily scalable: we demonstrate a parallel system that generates droplets simultaneously, and improves the droplet production rate by up to one order-of-magnitude. Finally, we show the potential application of our system for encapsulating cells in water-in-water emulsions, by encapsulating microparticles and cells. To the best of our knowledge, our microfluidic technique is the first that forms low interfacial tension ATPS droplets without applying external perturbations. We anticipate that this simple approach will find utility in drug and cell delivery applications because of the all-biocompatible nature of the water-in-water ATPS environment.

Polysaccharide Structures in the Outer Mucilage of Arabidopsis Seeds Visualized by AFM

2020 ◽  
Author(s):  
MAK Williams ◽  
V Cornuault ◽  
AH Irani ◽  
VV Symonds ◽  
J Malmström ◽  
...  
Keyword(s):  
Average Length ◽  
American Chemical Society ◽  
Md Simulations ◽  
Chemical Society ◽  
Side Chains ◽  
Rhamnogalacturonan I ◽  
Afm Imaging ◽  
Minor Population ◽  
The Stability ◽  
A Minor

© 2020 American Chemical Society. Evidence is presented that the polysaccharide rhamnogalacturonan I (RGI) can be biosynthesized in remarkably organized branched configurations and surprisingly long versions and can self-assemble into a plethora of structures. AFM imaging has been applied to study the outer mucilage obtained from wild-type (WT) and mutant (bxl1-3 and cesa5-1) Arabidopsis thaliana seeds. For WT mucilage, ordered, multichain structures of the polysaccharide RGI were observed, with a helical twist visible in favorable circumstances. Molecular dynamics (MD) simulations demonstrated the stability of several possible multichain complexes and the possibility of twisted fibril formation. For bxl1-3 seeds, the imaged polymers clearly showed the presence of side chains. These were surprisingly regular and well organized with an average length of ∼100 nm and a spacing of ∼50 nm. The heights of the side chains imaged were suggestive of single polysaccharide chains, while the backbone was on average 4 times this height and showed regular height variations along its length consistent with models of multichain fibrils examined in MD. Finally, in mucilage extracts from cesa5-1 seeds, a minor population of chains in excess of 30 μm long was observed.

Theoretical Post-Dryout Heat Transfer Model

2018 ◽  
Vol 1 (1) ◽  
pp. 142-150
Author(s):  
Murat Tunc ◽  
Ayse Nur Esen ◽  
Doruk Sen ◽  
Ahmet Karakas
Keyword(s):  
Heat Transfer ◽  
Droplet Diameter ◽  
Heat Transfer Model ◽  
Transfer Model ◽  
Operating Pressure ◽  
Vertical Pipe ◽  
Two Phase ◽  
Experimental Values ◽  
Reactor Operating ◽  
Coolant System

A theoretical post-dryout heat transfer model is developed for two-phase dispersed flow, one-dimensional vertical pipe in a post-CHF regime. Because of the presence of average droplet diameter lower bound in a two-phase sparse flow. Droplet diameter is also calculated. Obtained results are compared with experimental values. Experimental data is used two-phase flow steam-water in VVER-1200, reactor coolant system, reactor operating pressure is 16.2 MPa. On heater rod surface, dryout was detected as a result of jumping increase of the heater rod surface temperature. Results obtained display lower droplet dimensions than the experimentally obtained values.

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