Oxygen flow rate

Other techniques include oxidative, steam atmosphere (33), and molten salt (34) pyrolyses. In a partial-air atmosphere, mbber pyrolysis is an exothermic reaction. The reaction rate and ratio of pyrolytic filler to ok products are controlled by the oxygen flow rate. Pyrolysis in a steam atmosphere gives a cleaner char with a greater surface area than char pyroly2ed in an inert atmosphere however, the physical properties of the cured compounded mbber are inferior. Because of the greater surface area, this pyrolytic filler could be used as activated carbon, but production costs are prohibitive. Molten salt baths produce pyroly2ed char and ok products from tine chips. The product characteristics and quantities depend on the salt used. Recovery of char from the molten salt is difficult. 

The lignin (50 g) was dissolved in a mixture of dioxane (500 ml) and methanol (1,000 ml), and ozonized at 0°C with an oxygen flow rate of 0.5 ml/min and ozone concentration of 3% as shown in Figure 3. After treatment with ozone, the solution was treated with an excess amount of ether, and the insoluble fraction was filtered off, followed by drying under vacuum. Three samples (No. 1, No. 2, and No. 3) differed in the extent of ozone treatment as shown in Table I. The molar equivalents were based on the ratio of ozone to each phenylpropane (C9) unit. The yield of each sample is also shown in Table I. 

The overall reaction rate is proportional to [Cr(II)]2[02], but at the same time it was found that the rate was proportional to the oxygen flow rate, and the results are not easily interpreted. The 180 labeling experiments show that both of the oxygen atoms from 02 are incorporated into the dinuclear species without exchanging with solvent during the oxidation (197). These observations have been interpreted in terms of the mechanism of Eqs. (14) (16). 

Factors that affect the rate of low-temperature ashing other than radiofrequency power and oxygen flow rate are the coal particle size and depth of sample bed. Typical conditions for ashing are a particle size of less than 80 mesh, a sample layer density of 30 mg/cm2, oxygen flow rate of 100 cm3/min, chamber pressure of about 2 torr, and a 50-W net radio-frequency power. The total time required is 36 to 72 hours, and specified conditions must be met during the procedure to obtain reproducible results. 

Fig. 4.8 Flow field arrows on the cathode side, when the oxygen flow rate is 12 N1 h 1, and the cell voltage is 0.8 V at 360 mA cm 1.

Turn on oxygen tank and adjust oxygen flow rate to 1 liter per minute (11pm). 

U liters (a round bottomed flask) and 185 liters (a 6.5 ft stainless steel rotary digester). Temperatures within the vessels were regulated by partial immersion in controlled (to 100°C) water baths. Aqueous nitric acid was introduced as either a fine stream or spray into the vessels both nitric oxide and oxygen flow rate and pressure drop were independently monitored into the systems. 

A modified Coleman Model 33 Carbon-Hydrogen Analyzer was used to control the oxygen flow rate, to pretreat the oxygen (anhydrous magnesium perchlorate and anhydrous lithium hydroxide) and to hold the combustion tube in position. The analyzers furnace was controlled by a Fisher Model 360 Linear Temperature Programme. The rate of temperature increase was variable from 0.5 to 25 C per minute. Normally, the temperature programmer... 

By varying the temperature of the precursor pot, different partial pressures of [Y(TMHD)3] could be generated, as was reflected by different values of absorbances at 200°C. Comparison of absorbance values at a temperature where decomposition was occurring, such as at 460°C (cf. Fig. 17.12(b)), with the corresponding values at 200°C then allowed determination of the order of reaction with respect to [Y(TMHD)3]. From the data plotted in Fig. 17.13 it can be seen that the reaction is first order. The data is plotted for the C=C stretch at 1571 cm-1, but a similar result was obtained for the other absorbance frequencies. For a fixed precursor partial pressure (i.e., at a constant precursor pot temperature) variation of the oxygen flow rate allowed determination of the reaction order with... 

In the basis of this simplified reaction scheme, two techniques have been proposed for the estimation of the instantaneous current efficiency (ICE) during electrolysis the chemical oxygen demand (COD) and the oxygen flow rate (OFR) techniques. 

An ozonizer similar to that described by Henne and Peril-stein 2 was employed. At an oxygen flow rate of 30 l./hr. it produced about 30 millimoles of 03 per hour (3% conversion). Under these conditions the ozonization of 25 g. of pyrene requires about 6 hours. 

Figure 1. Electron concentration n and electron mobility i measured by Hall effect of ZnO films prepared by reactive magnetron sputtering as a fimction of the oxygen flow rate f(02). SEM micrographs taken on samples in the three regions of low, medium and high f(02). ...

In a reactive sputtering process the oxygen flow rate f(02) is the most relevant parameter. Fig. 1 displays a typical example of the influence of f(02) on physical properties and structure. Hall effect measurements show that the free carrier concentration n decreases continuously with f(02) whereas the electron mobility attains a maximum at medium values of f(02). This variation of the n and p clearly reflects the change from metallic behavior at low f(02) (region I) to oxide formation (region III) at high f(02) which is related with an increase of the optical transmission T. These changes are accompanied by structural variations in the ZnO layers. The SEM... 

FIGURE 22. Influence of substrate temperature and oxygen flow rates on the stoichiometry of the films grown by AP-CVD (top) and DLI-CVD (bottom). M = monocUnic phase, B = metastable monocfinic phase appearing in nanocrystalUne form. Reproduced from Reference 325 by permission of Wiley-VCH... 

Figure 30.5 The effects of input power (A) 8 W, (B) 30 W, (C) 63 W, and system pressure (1) 25mtorr, (2) 50mtorr, (3) lOOmtorr, on Wilhelmy force loops of O2 plasma-treated LDPE oxygen flow rate and plasma treatment time were fixed at 10 seem and 0.2 min, respectively, dark-colored force loops were taken just after samples were removed from the reactor, and gray-colored force loops were taken two weeks later after equilibrating with ambient air.

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