Inductively coupled reactor

In such a capacitive discharge, powder formation was stated to occur in the region of low pressure and low flow rate, whereas in the inductively coupled reactor used by Liepins and Sakaoku [7] it was found to occur under conditions of high flow rate and high pressure. The critical parameter for powder formation, however, was reported by Kobayashi et al. [9] to be the energy input per mole of gas. They reported that for a pressure of 2 torr, the approximate values of the critical energy input of 50, 100, and 150 W correspond to dosages of 2.68 x 10, 2.9 x 10, and 2.08 X lO J/mole, respectively. 

We may compare results presented here with those obtained in two types of inductively coupled reactors [, 3]. One is the reactor we have used for many years [4], in which the portion of the reactor inserted into the r.f. coil is smaller than the main portion of the reactor, in which plasma polymer is collected. Monomer flux is directed into the main portion of the reactor, not through the r.f. coil. Electron bombardment of plasma polymer and substrate is reduced in this way [ ]. Active species are formed mainly under the r.f. coll and are transported by diffusion to the entire volume of the reactor. Interaction of these non-polymerizable energy carrying species (e.g. electrons, excited atoms) with the monomer entering the reactor leads to plasma polymerization [ ]. 

Application to inductively-coupled reactors When modeling inductively coupled systems (Fig. 20a), the electric field powering the electrons is azimuthal. In the case of... 

One way to fabricate such a reactor is by deep reactive ion etching (DRIE) with a time-multiplexed inductively coupled plasma etcher (most details on fabrication are given in [77]) [7, 77, 78]. Regions of major importance such as the retainers are etched through to avoid differences in stmctural depth which may cause uneven flow. To generate various channel depths in one design, both front-side and back-... 

Other configurations that are used include an concentric electrode setup in a tubular reactor, where the discharge still is capacitivily coupled. Also, inductive coupling has been used, with a coil surrounding the tubular reactor [146, 147]. 

Continuous production of fullerenes was possible by pyrolysis of acetylene vapor in a radio-frequency induction heated cylinder of glassy polymeric carbon having multiple holes through which the gas mixture passes [44]. Fullerene production is seen at temperatures not exceeding 1500 K. The yield of fullerenes, however, generated by this method is less than 1%. A more efficient synthesis (up to 4.1% yield) was carried out in an inductively coupled radio-frequency thermal plasma reactor [45]. 

Table 8.1.5 Processing Conditions for the Synthesis of Silicon Nitride UFPs by an Inductively Coupled RF-Plasma Torch Reactor...

Until now, little attention has been given to the analysis of ancient copper alloys with LA-ICP-MS. This type of material is usually analyzed with fast or instrumental neutron activation analysis (FNAA or INAA), particle induced X-ray emission (PIXE), X-ray fluorescence (XRF), inductively coupled plasma-atomic emission spectrometry or inductively coupled plasma-atomic absorption spectrometry (ICP-AES or ICP-AAS). Some of these techniques are destructive and involve extensive sample preparation, some measure only surface compositions, and some require access to a cyclotron or a reactor. LA-ICP-MS is riot affected by any of these inconveniences. We propose here an analytical protocol for copper alloys using LA-ICP-MS and present its application to the study of Matisse bronze sculptures. 

The compositions of the ceramic glazes were examined using laser-ablation inductively coupled-mass spectroscopy (LA-ICP-MS) at the University of Missouri Research Reactor (MURR). LA-ICP-MS is a surface analysis technique requiring little sample preparation. Because of its small spot size, areas of weathered glaze could be avoided during analysis (24). 

The present report describes the preparation of spherical ceramic particles of different kind and of different size in an inductively coupled RF thermal plasma reactor. The effect of plasma gases and the type of the feedstock materials on the microstructure of the formed particles was studied in the experiments. 

Besser et al. [86] studied the reaction in a silicon reactor fabricated by applying MEMS technology, namely photolithography and DRIE by inductively coupled plasma. Each reactor incorporated dual gas inlets, a pre-mixer, a single reaction channel and an outlet zone where the product flow was cooled (see Figure 2.54). The single channel was 500 pm wide, 470 pm deep and 45 mm long. 

Figure 11 Geometries of plasma-assisted CVD reactors (A) parallel-plate discharge, (B) tube with capacitive coupling, (C) tube with inductive coupling.13...

Chlorine and bromine atoms were generated using UV and visible photolysis of molecular chlorine and bromine, respectively, in addition to UV (300 < k < 400 nm) photolysis of chloroacetyl chloride and dibromomethane. The reaction products were analyzed in the gas-phase, in suspended aerosols and on the wall of the reactor using MS, GC-MS and inductively coupled plasma mass spectrometry (ICP-MS). The major products identified were HgCb and HgBr2 adsorbed on the wall. Suspended aerosols, collected on the micron filters, contributed to less than... 

There are two important questions which may readily be addressed by ESCA. Firstly, what is the rate of deposition of the polymer film at a given site in a plasma reactor and secondly how does the structure depend on the site of deposition To illustrate the great power of the technique in answering these questions we consider here a recent detailed investigation of the inductively coupled plasma polymerization of pentafluorobenzene (13). 

Fig. 11 Schematic diagram of an inductively-coupled plasma reactor.

RF discharges are classified in accordance to their electrode or electrodeless nature into capacitively or inductively coupled. In the case of the inductively coupled discharge, a helical or flat copper coil is utilised. Inductive coupling is generally used at AC frequencies greater than 1 MHz as it becomes less efficient at lower frequencies. Although systems are often described as inductively coupled this may not be the case as the skin depth (the distance over which the electromagnetic radiation is absorbed) is often in excess of the reactor dimensions. This is certainly the case for the 13.56 MHz systems widely employed for polymer deposition. 

A fit-for-purpose estimate of the individual activities is needed for waste disposal purposes and calculation of neutron activation of precursors is often the simplest method, where contamination is unimportant. For H, the concentration of the Li precursor is required. The mobile nature of is a complicating factor since, in principle, it may remain in situ or diffuse within the bulk material. The aim of this work was to provide some answers to the above questions by determining the concentrations of Li in reactor steels and to compare the predicted levels of with values measured in reactor surveillance specimens. Preliminary attempts to measure Li in reactor steels by ICP-OES (inductively coupled plasma - optical emission spectroscopy) were not successful and... 

Vanadium molecular size distributions in residual oils are measured by size exclusion chromatography with an inductively coupled plasma detector (SEC-ICP). These distributions are then used as input for a reactor model which incorporates reaction and diffusion in cylindrical particles to calculate catalyst activity, product vanadium size distributions, and catalyst deactivation. Both catalytic and non-catalytic reactions are needed to explain the product size distribution of the vanadium-containing molecules. Metal distribution parameters calculated from the model compare well with experimental values determined by electron microprobe analysis, Modelling with feed molecular size distributions instead of an average molecular size results in predictions of shorter catalyst life at high conversion and longer catalyst life at low conversions. 

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