Continuous Liquid Vapor Reactions Part 1: Design and Characterization of a Reactor for Asymmetric Hydroformylation

2016 ◽  
Vol 20 (5) ◽  
pp. 888-900 ◽  
Author(s):  
Martin D. Johnson ◽  
Scott A. May ◽  
Joel R. Calvin ◽  
Gordon R. Lambertus ◽  
Prashant B. Kokitkar ◽  
...  
Keyword(s):  
Asymmetric Hydroformylation ◽  
Liquid Vapor

Atomistic and macroscopic characterization of nanoscale thin film liquid-vapor phase change phenomena

2021 ◽  
Vol 170 ◽  
pp. 107159
Author(s):  
Md Muntasir Alam ◽  
Md Shajedul Hoque Thakur ◽  
Mahmudul Islam ◽  
Mohammad Nasim Hasan ◽  
Yuichi Mitsutake ◽  
...  
Keyword(s):  
Thin Film ◽  
Phase Change ◽  
Vapor Phase ◽  
Nanoscale Thin Film ◽  
Phase Change Phenomena ◽  
Liquid Vapor

Continuous Liquid Vapor Reactions Part 2: Asymmetric Hydroformylation with Rhodium-Bisdiazaphos Catalysts in a Vertical Pipes-in-Series Reactor

2016 ◽  
Vol 20 (5) ◽  
pp. 901-910 ◽  
Author(s):  
M. Leigh Abrams ◽  
Jonas Y. Buser ◽  
Joel R. Calvin ◽  
Martin D. Johnson ◽  
Bradley R. Jones ◽  
...  
Keyword(s):  
In Series ◽  
Asymmetric Hydroformylation ◽  
Liquid Vapor

scholarly journals Experimental study of liquid-vapor mass transfer in non-reacting and reacting droplet chains

2017 ◽  
Author(s):  
Michael Stöhr ◽  
Stefanie Werner ◽  
Wolfgang Meier
Keyword(s):  
Mass Transfer ◽  
Spatial Resolution ◽  
Spatial Scales ◽  
Droplet Evaporation ◽  
Small Scale ◽  
Acetone Vapor ◽  
Calibration Measurement ◽  
Vapor Mass ◽  
Liquid Vapor

The dynamics of liquid-vapor mass transfer largely determines the performance of internal and gas turbine spraycombustors. The key mechanisms however typically take place on small spatial scales of less than 100 μm which have been difficult to measure. The present work thus aims at the development and application of an experimental technique for the characterization of droplet evaporation with high spatial resolution. Single chains of monodisperse acetone droplets with diameters of 125 and 225 μm are injected into a channel with a cross-section of 60x60 mm² and quartz glass side walls for optical access. The droplet chains are surrounded by a laminar air flow with velocity and temperature of about 0.1 m/s and 300 K, respectively. The distribution of acetone vapor around the droplets is measured using planar laser-induced fluorescence (PLIF) excited by the 4th harmonic of a Nd:YAG laser at 266 nm. The measurements are performed in thin transversal sections between the droplets in order to avoid signal corruption by halation effects that occur when the laser directly hits the droplets as reported in previous studies. In addition, the spatial resolution of the PLIF setup was enhanced by using proper sheet- forming and imaging optics. The resulting in-plane resolution and out-plane-resolution (i.e. thickness of the laser sheet) are both determined to about 20 μm, which thus allows an accurate characterization of the small-scale vapor distribution near the droplets. Using a separate calibration measurement, quantitative acetone concentrations are obtained for non-reacting conditions. As a complementary technique, the droplet evaporation is measured using shadowgraphy droplet sizing. Both non-reacting and reacting droplet chains are studied. The results for the non-reacting cases show that the droplet chains are surrounded by a column of nearly-saturated acetone vapor with a concentration maximum at the centerline. For increasing radial distances, the vapor concentration decays quickly with a half width of 0.5 mm and reaches almost zero for r>1 mm. It is further seen that the width of the vapor column increases with streamwise distance. For the experiment with a reacting droplet chain, which is continuously ignited by a heating wire at the channel inlet, a cylindrical reaction zone around the chain with a radius of about 1.5 mm is observed. The shadowgraphy measurements show that the rate of droplet evaporation is significantly enhanced for the reacting conditions. This is attributed to the high rate of heat transfer from the flame to the droplets and the resulting enhanced acetone mass transfer to the sink at the reaction zone.DOI: http://dx.doi.org/10.4995/ILASS2017.2017.4767

Characterization of Interfacial Mass Transfer Rate of Stored Liquids

2015 ◽  
Vol 7 (2) ◽  
Author(s):  
Dibakar Rakshit ◽  
R. Narayanaswamy ◽  
K. P. Thiagarajan
Keyword(s):  
Mass Transfer ◽  
Transfer Rate ◽  
Mass Transfer Rate ◽  
Two Phase ◽  
Interfacial Mass Transfer ◽  
Different Temperatures ◽  
Interfacial Temperature ◽  
Fill Level ◽  
Liquid Vapor

A thermodynamic analysis of the two-phase physics involving a liquid–vapor combination has been studied under the regime of conjugate heat and mass transfer phenomena. An experiment has been designed and performed to estimate the interfacial mass transfer characteristics of a liquid–vapor system by varying the liquid temperature. The experimental setup consists of an instrumented tank partially filled with water and maintained at different temperatures. The evaporation of liquid from the interface and the gaseous condensation has been quantified by calculating the interfacial mass transfer rate for both covered and uncovered tanks. The dependence of interfacial mass transfer rate on the liquid–vapor interfacial temperature, fractional concentration of the evaporating liquid, the surface area of the liquid vapor interface, and the fill level of the liquid has been established through the present experimental study. An estimation of the overall mass transfer rate from the interface due to a concentration gradient shows an analogy with the multiphase heat transfer that takes place across the interface due to temperature gradient. It was seen that at low fill levels and with a temperature difference of about 30 °C between liquid and ullage, the mass transfer rate of a closed system was nearly doubled when compared to its open system counterpart.

scholarly journals Characterization of a Condenser for a High Performance Multi-Condenser Loop Heat Pipe

2011 ◽  
Author(s):  
Daniel F. Hanks ◽  
Teresa B. Peters ◽  
John G. Brisson ◽  
Evelyn N. Wang
Keyword(s):  
Heat Pipe ◽  
Thermal Management ◽  
Heat Sink ◽  
High Performance ◽  
Electronic Systems ◽  
Loop Heat Pipe ◽  
Particle Sizes ◽  
Vapor Interface ◽  
Liquid Vapor

We experimentally characterized a condenser design for a multi-condenser loop heat pipe (LHP) capable of dissipating 1000 W. The LHP is designed for integration into a high performance air-cooled heat sink to address thermal management challenges in advanced electronic systems. The multi-layer stack of condensers utilizes a sintered wick design to stabilize the liquid-vapor interface and prevent liquid flooding of the lower condenser layers in the presence of a gravitational head. In addition a liquid subcooler is incorporated to suppress vapor flashing in the liquid return line. We fabricated the condensers using photo-chemically etched Monel frames with Monel sintered wicks with particle sizes up to 44 μm. We characterized the performance of the condensers in a custom experimental flow rig that monitors the pressure and temperatures of the vapor and liquid. The condenser dissipated the required heat load with a subcooling of up to 18°C, while maintaining a stable liquid-vapor interface with a capillary pressure of 6.2 kPa. In the future, we will incorporate the condenser into a loop heat pipe for a high performance air-cooled heat sink.

Morphological Characterization of Mycobacteriophage R1

1974 ◽  
Vol 32 ◽  
pp. 254-255
Author(s):  
B. L. Soloff ◽  
T. A. Rado
Keyword(s):  
Carbon Source ◽  
Stationary Phase ◽  
Growth Phase ◽  
Minimal Medium ◽  
Morphological Characterization ◽  
Logarithmic Growth Phase ◽  
Complete Lysis ◽  
Lysogenic Culture ◽  
Logarithmic Growth

Mycobacteriophage R1 was originally isolated from a lysogenic culture of M. butyricum. The virus was propagated on a leucine-requiring derivative of M. smegmatis, 607 leu−, isolated by nitrosoguanidine mutagenesis of typestrain ATCC 607. Growth was accomplished in a minimal medium containing glycerol and glucose as carbon source and enriched by the addition of 80 μg/ ml L-leucine. Bacteria in early logarithmic growth phase were infected with virus at a multiplicity of 5, and incubated with aeration for 8 hours. The partially lysed suspension was diluted 1:10 in growth medium and incubated for a further 8 hours. This permitted stationary phase cells to re-enter logarithmic growth and resulted in complete lysis of the culture.

AEM analysis of crystallization in Ti-based amorphous alloys

1983 ◽  
Vol 41 ◽  
pp. 270-271
Author(s):  
A.R. Pelton ◽  
A.F. Marshall ◽  
Y.S. Lee
Keyword(s):  
Magnetic Properties ◽  
Amorphous Alloys ◽  
Amorphous Materials ◽  
Isothermal Annealing ◽  
Amorphous Matrix ◽  
Nucleation And Growth ◽  
Current Interest ◽  
Amorphous Films ◽  
Electrical And Magnetic Properties

Amorphous materials are of current interest due to their desirable mechanical, electrical and magnetic properties. Furthermore, crystallizing amorphous alloys provides an avenue for discerning sequential and competitive phases thus allowing access to otherwise inaccessible crystalline structures. Previous studies have shown the benefits of using AEM to determine crystal structures and compositions of partially crystallized alloys. The present paper will discuss the AEM characterization of crystallized Cu-Ti and Ni-Ti amorphous films.Cu60Ti40: The amorphous alloy Cu60Ti40, when continuously heated, forms a simple intermediate, macrocrystalline phase which then transforms to the ordered, equilibrium Cu3Ti2 phase. However, contrary to what one would expect from kinetic considerations, isothermal annealing below the isochronal crystallization temperature results in direct nucleation and growth of Cu3Ti2 from the amorphous matrix.

Characterization of Coherent, Ordered Precipitates in Nickel-Base Alloys

1973 ◽  
Vol 31 ◽  
pp. 144-145
Author(s):  
B. H. Kear ◽  
J. M. Oblak
Keyword(s):  
Stable Phase ◽  
Nickel Base Superalloy ◽  
Alloy 718 ◽  
Commercial Alloy ◽  
Precipitate Morphology ◽  
Continuous Precipitation ◽  
Nickel Base ◽  
Base Superalloy ◽  
Strengthening Precipitate

A nickel-base superalloy is essentially a Ni/Cr solid solution hardened by additions of Al (Ti, Nb, etc.) to precipitate a coherent, ordered phase. In most commercial alloy systems, e.g. B-1900, IN-100 and Mar-M200, the stable precipitate is Ni3 (Al,Ti) γ′, with an LI2structure. In A lloy 901 the normal precipitate is metastable Nis Ti3 γ′ ; the stable phase is a hexagonal Do2 4 structure. In Alloy 718 the strengthening precipitate is metastable γ″, which has a body-centered tetragonal D022 structure.Precipitate MorphologyIn most systems the ordered γ′ phase forms by a continuous precipitation re-action, which gives rise to a uniform intragranular dispersion of precipitate particles. For zero γ/γ′ misfit, the γ′ precipitates assume a spheroidal.

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