Two-phase liquid phase epitaxy of In0.53Ga0.47As on InP

Author(s):  
Mu-Kuen Chen
Processes ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 413
Author(s):  
Sandra Lopez-Zamora ◽  
Jeonghoon Kong ◽  
Salvador Escobedo ◽  
Hugo de Lasa

The prediction of phase equilibria for hydrocarbon/water blends in separators, is a subject of considerable importance for chemical processes. Despite its relevance, there are still pending questions. Among them, is the prediction of the correct number of phases. While a stability analysis using the Gibbs Free Energy of mixing and the NRTL model, provide a good understanding with calculation issues, when using HYSYS V9 and Aspen Plus V9 software, this shows that significant phase equilibrium uncertainties still exist. To clarify these matters, n-octane and water blends, are good surrogates of naphtha/water mixtures. Runs were developed in a CREC vapor–liquid (VL_ Cell operated with octane–water mixtures under dynamic conditions and used to establish the two-phase (liquid–vapor) and three phase (liquid–liquid–vapor) domains. Results obtained demonstrate that the two phase region (full solubility in the liquid phase) of n-octane in water at 100 °C is in the 10-4 mol fraction range, and it is larger than the 10-5 mol fraction predicted by Aspen Plus and the 10-7 mol fraction reported in the technical literature. Furthermore, and to provide an effective and accurate method for predicting the number of phases, a machine learning (ML) technique was implemented and successfully demonstrated, in the present study.


2004 ◽  
Vol 69 (7) ◽  
pp. 581-599 ◽  
Author(s):  
Ljubisa Nikolic ◽  
Vesna Nikolic ◽  
Vlada Veljkovic ◽  
Miodrag Lazic ◽  
Dejan Skala

The influence of the gas flow rate and vibration intensity in the presence of the solid phase (polypropylene spheres) on axial mixing of the liquid phase in a three phase (gas-liquid-solid) Karr reciprocating plate column (RPC) was investigated. Assuming that the dispersionmodel of liquid flow could be used for the real situation inside the column, the dispersion coefficient of the liquid phase was determined as a function of different operating parameters. For a two-phase liquid-solid RPC the following correlation was derived: DL = 1.26(Af)1.42 UL 0.51 ?S 0.23 and a similar equation could be applied with ? 30 % confidence for the calculation of axial dispersion in the case of a three-phase RPC: DL = 1.39(Af)0.47 UL0.42UG0.03 ?S -0.26.


2006 ◽  
Vol 12 (4) ◽  
pp. 241-245 ◽  
Author(s):  
Nada Nikolic ◽  
Mihajlo Stankovic ◽  
Milorad Cakic

A comparison of the results of the acid and enzymatic hydrolysis of GA from potato haulm and tuber sprouts is presented in this paper. Different systems were used for acid hydrolysis: monophase liquid, two-phase liquid-liquid or solid-liquid and three-phase solid-liquid-liquid systems. Enzymatic hydrolysis was carried out by enzymes present in fresh haulm and fresh tuber sprouts and the fresh juice obtained from fresh plant material. The procedure of acid hydrolysis of GA from potato sprouts in a two-phase liquid-liquid system was selected as the optimal procedure for obtaining solanidine. The liquid-liquid system was composed of GA extract with hydrochloric acid as the first liquid phase and chloroform as the second liquid phase. A degree of GA hydrolysis of 96% and a solanidine yield of 1.50 g per 100 g of dried tuber sprouts after 90 minutes were then achieved.


Author(s):  
A.D. Khlopov ◽  
M.S. Frantsuzov

In this paper, the outflow of liquid in the coflowing airstream from a shock-jet nozzle is examined using a commercial software package with varying initial and boundary conditions. Gas-dynamic characteristics and distribution fields for pressure, velocity, temperature and volume fraction of the two-phase flow are obtained. The influence of thermophysical properties of the liquid on the process of jet dispersion is determined. The results of simulation of the liquid outflow from the shock-jet nozzle at constant and real (temperature dependent) thermophysical properties of the liquid phase are compared. The qualitative and quantitative influence of the input pressure in the nozzle on the jet dispersion process is determined. As a result of a series of calculations, the minimum required characteristics of temporal and spatial resolution for the correct solution of the problem are identified. It is established that the volume content of the liquid phase is higher with real thermophysical properties compared to the constant ones.


Author(s):  
N.A. Bert ◽  
A.O. Kosogov

The very thin (<100 Å) InGaAsP layers were grown not only by molecular beam epitaxy and metal-organic chemical vapor deposition but recently also by simple liquid phase epitaxy (LPE) technique. Characterization of their thickness, interfase abruptness and lattice defects is important and requires TEM methods to be used.The samples were InGaAsP/InGaP double heterostructures grown on (111)A GaAs substrate. The exact growth conditions are described in Ref.1. The salient points are that the quarternary layers were being grown at 750°C during a fast movement of substrate and a convection caused in the melt by that movement was eliminated. TEM cross-section specimens were prepared by means of conventional procedure. The studies were conducted in EM 420T and JEM 4000EX instruments.The (200) dark-field cross-sectional imaging is the most appropriate TEM technique to distinguish between individual layers in 111-v semiconductor heterostructures.


Author(s):  
F. Banhart ◽  
F.O. Phillipp ◽  
R. Bergmann ◽  
E. Czech ◽  
M. Konuma ◽  
...  

Defect-free silicon layers grown on insulators (SOI) are an essential component for future three-dimensional integration of semiconductor devices. Liquid phase epitaxy (LPE) has proved to be a powerful technique to grow high quality SOI structures for devices and for basic physical research. Electron microscopy is indispensable for the development of the growth technique and reveals many interesting structural properties of these materials. Transmission and scanning electron microscopy can be applied to study growth mechanisms, structural defects, and the morphology of Si and SOI layers grown from metallic solutions of various compositions.The treatment of the Si substrates prior to the epitaxial growth described here is wet chemical etching and plasma etching with NF3 ions. At a sample temperature of 20°C the ion etched surface appeared rough (Fig. 1). Plasma etching at a sample temperature of −125°C, however, yields smooth and clean Si surfaces, and, in addition, high anisotropy (small side etching) and selectivity (low etch rate of SiO2) as shown in Fig. 2.


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