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Experimental converters

In the experimental converter of Fig. 1, collector surface covered by a NbOx layer serves as a reservoir of electronegative gas (oxygen-contained molecule), which reduces the emitter work function. Therefore Tc has a large effect on the converter performance. [Pg.665]

Also in 1970, the Perris experimenters converted a newer Ford pickup truck, an F250 with a 6-cylinder engine, to run on liquid hydrogen and liquid oxygen. The whole idea was to have absolutely no impact on the atmosphere, Dieges told me in a March 1999 telephone conversation. [Pg.134]

One of the first steps taken in Ludwigshafen in 1910 was to build two experimental converters appreciably larger than Haber s laboratory model (fig. 5.2). Then Mannes-mann produced the contact tubes 2.5 m long with a 15 cm inside diameter and wall thickness about 30 mm for the first technical trials (fig. 5.3). They were heated electrically from the outside, filled with the catalyst, and housed in reinforced concrete chambers. Both tubes burst after about eighty hours of operation under high pressure. ... [Pg.87]

An X-ray image of a test object is converted by a X-ray TV unit (4), and complete video-signal from it is supplied to specialized computer (5). For conversion of X-ray images series X-ray vidicons LI-444 and LI-473 can be used or experimental X-ray vidicons of the same dimensions with a Be input window [2] sensitive to soft X-radiation developed in Introscopy Institute. >. ... [Pg.449]

The characteristic isotherm concept was elaborated by de Boer and coworkers [90]. By accepting a reference from a BET fit to a standard system and assuming a density for the adsorbed film, one may convert n/rim to film thickness t. The characteristic isotherm for a given adsorbate may then be plotted as t versus P/P. For any new system, one reads t from the standard r-curve and n from the new isotherm, for various P/P values. De Boer and co-work-ers t values are given in Table XVII-4. A plot of t versus n should be linear if the experimental isotherm has the same shape as the reference characteristic isotherm, and the slope gives E ... [Pg.633]

In the example of the previous section, the release of the stop always leads to the motion of the piston in one direction, to a final state in which the pressures are equal, never in the other direction. This obvious experimental observation turns out to be related to a mathematical problem, the integrability of differentials in themiodynamics. The differential Dq, even is inexact, but in mathematics many such expressions can be converted into exact differentials with the aid of an integrating factor. [Pg.333]

I CRS interferogram with a frequency of A = coj + 2c0j - cOq, where cOp is the detected frequency, coj is the narrowband frequency and coj the Raman (vibrational) frequency. Since cOq and coj are known, Wj may be extracted from the experimentally measured RDOs. Furthemiore, the dephasing rate constant, yj, is detemiined from the observed decay rate constant, y, of the I CRS interferogram. Typically for the I CRS signal coq A 0. That is, the RDOs represent strongly down-converted (even to zero... [Pg.1209]

Here, k is a factor which converts to units (kcal/mol in this case where the distances are in A and the polarisabilities in A ). G, and Gj are constants chosen to reproduce the well depths for like-with-like interactions. The atomic polarisability values are obtained from an examination of appropriate molecular experimental data (such as measurements of molar refractivity). [Pg.229]

Drop 1 g. of sodium into 10 ml. of ethyl alcohol in a small flask provided with a small water condenser heat the mixture until all the sodium has dissolved. Cool, and add 1 g. of the ester and 0-5 ml. of water. Frequently the sodium salt of the acid will be deposited either at once or after boiling for a few minutes. If this occurs, filter oflF the solid at once, wash it with a little absolute ethyl alcohol (or absolute methylated spirit), and convert it into the p-bromophenacyl ester, p-nitro-benzyl ester or S-benzyl-tso-thiuronium salt (for experimental details, see Section 111,85). If no solid separates, continue the boiling for 30-60 minutes, boil oflF the alcohol, allow to cool, render the product just neutral to phenolphthalein with dilute sulphuric or hydrochloric acid, convert the sodium salt present in solution into a crystalline derivative (Section 111,85), and determine its melting point. [Pg.391]

The steps may be so chosen as to correspond to consecutive points on the experimental isotherm. In practice it is more convenient to divide the desorption process into a number of standard steps, either of relative pressure, or of pore radius, which is of course a function of relative pressure. The amount given up during each step i must be converted into a liquid volume i , (by use of the normal liquid density) in some procedures the conversion is deferred to a late stage in the calculation, but conceptually it is preferable to undertake the conversion at the outset. As indicated earlier, the task then becomes (i) to calculate the contribution dv due to thinning of the adsorbed film, and thus obtain the core volume associated with the mean core radius r by the subtraction = t ... [Pg.134]

The uptake, in column 10, has been converted into a liquid volume at the outset rather than at a later stage as in the original papers. Columns 1-8 are based on Table 3.2. In the original papers the values of p/p° corresponded to actual points on the experimental isotherm, but the work sheet is much simplified by the choice of standard intervals of pjp° (or of r " cf. p. 135). [Pg.136]

In practice, what is measured experimentally is not energy but frequency, in the millimetre wave and microwave regions, or wavenumber, in the far infrared. Therefore we convert the energy levels of Equation (5.10) to what are known as term values F J) having dimensions of either frequency, by dividing by h, or wavenumber, by dividing by he, giving... [Pg.106]

Fig. 11. Variation of heat-transfer coefficient, where O represents experimental results at 100 kPa , 500 kPa 0, 1000 kPa and , 2000 kPa, of pressure (23) for (a) a 0.061-mm glass—CO2 system (Group A particles) and (b) a 0.475-mm glass—N2 system (Group B and D particles). To convert kPa to psi,... Fig. 11. Variation of heat-transfer coefficient, where O represents experimental results at 100 kPa , 500 kPa 0, 1000 kPa and , 2000 kPa, of pressure (23) for (a) a 0.061-mm glass—CO2 system (Group A particles) and (b) a 0.475-mm glass—N2 system (Group B and D particles). To convert kPa to psi,...
Only 20—40% of the HNO is converted ia the reactor to nitroparaffins. The remaining HNO produces mainly nitrogen oxides (and mainly NO) and acts primarily as an oxidising agent. Conversions of HNO to nitroparaffins are up to about 20% when methane is nitrated. Conversions are, however, often ia the 36—40% range for nitrations of propane and / -butane. These differences ia HNO conversions are explained by the types of C—H bonds ia the paraffins. Only primary C—H bonds exist ia methane and ethane. In propane and / -butane, both primary and secondary C—H bonds exist. Secondary C—H bonds are considerably weaker than primary C—H bonds. The kinetics of reaction 6 (a desired reaction for production of nitroparaffins) are hence considerably higher for both propane and / -butane as compared to methane and ethane. Experimental results also iadicate for propane nitration that more 2-nitropropane [79-46-9] is produced than 1-nitropropane [108-03-2]. Obviously the hydroxyl radical attacks the secondary bonds preferentially even though there are more primary bonds than secondary bonds. [Pg.36]

PV systems consist of arrays of cells that ate interconnected in panels or modules to increase total power output. Often the systems include sun-tracking equipment, as well as power-conditioning equipment to convert dc to ac. The systems can range in size from a simple one-panel, fixed-orientation unit to a vast field of modules that accurately track the movement of the sun. Electric utiUties in Europe, Japan, and the United States have hosted several experimental PV power plants. The largest to date was a 5.5-MW plant at Carrisa Plains, California, built by Siemens Solar Industries (formerly ARCO Solar). [Pg.104]

As shown in equation 12, the chemistry of this developer s oxidation and decomposition has been found to be less simple than first envisioned. One oxidation product, tetramethyl succinic acid (18), is not found under normal circumstances. Instead, the products are the a-hydroxyacid (20) and the a-ketoacid (22). When silver bromide is the oxidant, only the two-electron oxidation and hydrolysis occur to give (20). When silver chloride is the oxidant, a four-electron oxidation can occur to give (22). In model experiments the hydroxyacid was not converted to the keto acid. Therefore, it seemed that the two-electron intermediate triketone hydrate (19) in the presence of a stronger oxidant would reduce more silver, possibly involving a species such as (21) as a likely reactive intermediate. This mechanism was verified experimentally, using a controlled, constant electrochemical potential. At potentials like that of silver chloride, four electrons were used at lower potentials only two were used (104). [Pg.509]


See other pages where Experimental converters is mentioned: [Pg.138]    [Pg.827]    [Pg.78]    [Pg.88]    [Pg.89]    [Pg.138]    [Pg.827]    [Pg.78]    [Pg.88]    [Pg.89]    [Pg.240]    [Pg.510]    [Pg.1806]    [Pg.1957]    [Pg.2399]    [Pg.2811]    [Pg.2838]    [Pg.44]    [Pg.96]    [Pg.632]    [Pg.257]    [Pg.258]    [Pg.40]    [Pg.326]    [Pg.260]    [Pg.463]    [Pg.25]    [Pg.34]    [Pg.425]    [Pg.490]    [Pg.285]    [Pg.344]    [Pg.467]    [Pg.308]    [Pg.121]    [Pg.313]    [Pg.317]    [Pg.318]    [Pg.329]   
See also in sourсe #XX -- [ Pg.78 , Pg.79 , Pg.80 , Pg.81 ]




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