Heat equivalent

V-Phenylsuccinimide [83-25-0] (succanil) is obtained in essentially quantitative yield by heating equivalent amounts of succinic acid and aniline at 140—150°C (25). The reaction of a primary aromatic amine with phosgene leads to formation of an arylcarbamoyl chloride, that when heated loses hydrogen chloride to form an isocyanate. Commercially important isocyanates are obtained from aromatic primary diamines. 

Looking at this low temperature refrigeration as to power requirement, one expander horsepower removes its heat equivalent to 2,545 Btu/lir, as eompared with 12,000 Btu/hr, about 4.7 times as mueh. This is refened to as a ton of refrigeration. Thus, the turhoexpander must develop 4.7 hp to generate a ton of refrigeration however, it delivers 4.7 hp haek as power. 

Hitze-gegenwert, m. heat equivalent, -grad, m. degree of heat. 

Ton of refrigeration The heat equivalent to melting 2,000 lb (one ton) of ice in 24 hours. One ton equals 12,000 Btu/hr or 200 Btu/min. To be comparative, refrigeration equipment must have the refrigerant level (or evaporation temperature) specified. 

The above calculations will give the heat losses after the building has been heated. Under conditions in which the heating system will operate continuously, satisfactory results will be obtained if the heating system is designed to provide heat equivalent to the amount calculated above. Suitable allowance must be made for losses from mains. 

Having obtained an accurate correlation for the annulus data at 1000 psia, Barnett applied it, for the same pressure, to the rod-bundle data, and Figs. 36 and 37 are two very convincing demonstrations of the connection that clearly exists between an annulus and a rod bundle. The method used in applying the annulus correlation was to assume a dt value equal to the diameter of the rods in the bundle considered, and a d0 value such that both annulus and bundle had the same heated equivalent diameter dh. All the normal rod-bundle data with vertical upflow were found to be well represented by the annulus correlation, but the nonnormal data showed the same disparity that was found in the rod-bundle analysis. Thus, we have a further indication that the non-normal rod bundles are showing markedly different burn-out behavior. 

The connection that has been shown in Section VIII to exist between burn-out in a rod bundle and in an annulus leads to the question of whether or not a link may also exist between, for example, a round tube and an annulus. Now, a round tube has its cross section defined uniquely by one dimension—its diameter therefore if a link exists between a round tube and an annulus section, it must be by way of some suitably defined equivalent diameter. Two possibilities that immediately appear are the hydraulic diameter, dw = d0 — dt, and the heated equivalent diameter, dh = (da2 — rf,2)/ however, there are other possible definitions. To resolve the issue, Barnett (B4) devised a simple test, which is illustrated by Figs. 38 and 39. These show a plot of reliable burn-out data for annulus test sections using water at 1000 psia. Superimposed are the corresponding burn-out lines for round tubes of different diameters based on the correlation given in Section VIII. It is clearly evident that the hydraulic and the heated equivalent diameters are unsuitable, as the discrepancies are far larger than can be explained by any inaccuracies in the data or in the correlation used. 

Chemistry deals with molecules not atoms. True thermodynamics knows no molecules with much less properties of molecules derived from chemical effects. Its origin is in such concerns as heat flow and the heat equivalent of mechanical work. Most of us have heard in physical chemistry about how it was the drilling of cannon barrels that created the connection between work and heat energy. One can take entire semester course on thermodynamics in physics and in engineering and never deal with the solution thermodynamics, which often dominates chemistry courses. To the extent that thermodynamics has been used in developing a theory for separation methods, it is almost entirely chemical thermodynamics. 

As an alternative to the Glu and Asp scaffolds, the A-(dialkyl)amide of diglycolic acid has been proposed (13). This is readily prepared by heating equivalent amounts of diglycolic anhydride and, for example, bis(octadecyl)amine in refluxing toluene for 48 hours followed by recrystallization from chloroform (mp 81-82 °C)J178 In a similar mode, polyoxyethylene of selected chain length has been used to prepare dicarboxylic acids which, upon mono-amidation with bis(alkyl)amines, yield lipo moieties (e.g., 14) that are coupled to selected amine groups of peptides to produce the peptide amphiphiles. 179180 ... 

If none of this work was wasted, we could use it to lift a 1000-lb rock up to the top of Mount Everest (which is about 26,000 ft high). But in the 1840s, Robert Mayer did not know the conversion factor of heat equivalent to work of 740 ft-lb per Btu. It had not been determined yet, because Dr. Mayer was the one who first discovered it. So Dr. Mayer had to use the following method. 

The benzophenone dichloride was prepared by heating equivalent molecular quantities of benzophenone and phosphorus pentachloride to 145-150° for two hours and then fractionating the mixture under reduced pressure. The product used for this preparation boiled at 201-202°/35 mm. 

After that, it is seen one step at llOkJ/mol, that is, a high value of adsorption heat this fact indicates that the NH3 molecules strongly interact through their dipole moments with the mordenite framework [31,49], Thereafter, a decrease of the adsorption heat up to a value of the adsorption heat, equivalent to the liquefaction heat of NH3 at 42kJ/mol, is seen [49],... 

In Rayleigh s treatment of the Boussinesq s problem, we realized that Joule s heat equivalent had to be cancelled, because in this problem the liquid was supposed to be an ideal one. This is - of course - as with many problems arising in the areas of... 

For mechanical heat equivalent, the following are recommended (a) For pumps, use 50 percent of the connected motor horsepower for centrifugal pumps that are deadheaded, unless better information is available, (b) For agitators, use 100 percent of the vendor rated shaft input horsepower for the input shaft (total power less drive and bearing inefficiencies) for the actual material in the vessel. 

J mechanical heat equivalent Hc enthalpy of the reaction products Unit ... 

The system has thus worked in a cycle and has performed work equivalent to area A BCD it had taken up heat equivalent to area ABFH at higher temperature T and discarded heat equivalent to area CDGE at lower temperature Tj. 

In these determinations the weighings were corrected for the buoyancy of the air, and the heat equivalent of one watt-second was taken as 0-2390 cal. 

If the transducer which has been tested with a calorimeter is used to sonicate another reactor, the calibration obtained with the calorimeter may give somewhat erroneous values of the delivered acoustic power. Separate calibrations should be made for each kind of condition thus the system should be considered as a n-n calorimeter and the methodology described above should be applied (i.e. the heat equivalent of the system should be determined together with a calculation of heat losses, or accurate independent calibration of the system with an electric heater). This approach can be very time consuming. 

The total enthalpy or heat demand, Q, requirement is the sum of the offset (determined from the pinch analysis) and the endothermic external heat load. Work terms for chemical potential and separations are converted to their heat equivalent. Table 2 shows the details of the efficiency calculation. The resulting efficiency is 66.9% (LHV). 

Energy, Heat Equivalent, kcal/mol H2 kcal/mol H2 Energy, Heat Equivalent , kcal/mol H2 kcal/mol H2... 

In absorption, the transfer of molecules from the vapor to the liquid is a condensation process that is accompanied by the release of an amount of heat equivalent to the latent heat of condensation of the components being absorbed. If the process is adiabatic, where no heat crosses the system boundaries, the heat released by absorption is converted to sensible heat, resulting in a temperature rise. This thermal effect is reversed in stripping since the stripped components are transferred from the liquid state to the vapor state. The latent heat of vaporization is responsible for a temperature drop in adiabatic stripping processes. 

Selivanova and Pakhorukov measured the integral heat of dissolution of H2Se03(cr) in a conventional calorimeter. The heat equivalent of the equipment was obtained by electrical calibration. The accuracy of the instrumentation was checked by a measurement of the enthalpy of dissolution of KCI to KCI(aq, 1 200). 

Miksche and Caldwell (Mil) have now reported that rats with double the injury reported by Caimie et al. (Cl) show a significant increase in heat production (14r-20%) and in average body temperature, when housed at 28 . From relatively contemporaneous analysis the former calculate that the heat equivalent of the urinary nitrogen excreted ac-coimted for only 17-36% of the actual increment and that the major portion of this heat increment was accoimted for by the van t Hoff effect (Qio effect) secondary to an elevation of the average body temperature. Cuthbertson (C21) had earlier noted in man that the calculated van t Hoff effect actually equated the observed increase in BMR in man. 

Even when the reaction cannot be carried out without a change in volume (say an increase in volume) the heat equivalent of the work... 

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