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Thennal methods

These thennal methods for preparing anides are limited in their generality. Most often fflnides are prepared in the laboratory from acyl chlorides, acid anhydrides, or esters, and these are the methods that you should apply to solving synthetic problems. [Pg.861]

W.W. Wendlandt, Thennal Methods of Analysis, Interscience-Wiley,... [Pg.439]

J.E- Hunter III and R-U Blaine, in "Purity DcKtmmatioos by Thennal Methods" (Eds R.L. Blaine and C.K. Schoff), ASTM Special Technical Publication 838. Ameticaa Socteiy for Testing and Matenals. Philadelphia. I9S4. p39. [Pg.136]

For a detailed description of thennal methods, see Principles of Thermal Analysis and Calorimetry, P. J. Haines, ed.. Cambridge, UK Royal Society of Chemistry, 2002 P. I. Haines, Thermal Methods of Analysis, London Blackic, 1995 B, Wunderlich, Thermal Analysis, Boston Academic Press, 1990 W, W, Wendlandt, Thermal Analysis,. rd ed.. New York Wiley, 1985. For recent reviews, see S- Vyazovktn.. Anal. Chem., 2006, 78. 3875 Anal. Chem., 2004, 76, 3299 Anai. Chem.. 2002, "4, 2749. For a description of thermal analysis instruments, see B. E. Erickson, Anal. Chem.. 1999, 7]. 689A. [Pg.456]

Flow tube studies of ion-moleeule reaetions date baek to the early 1960s, when the flowing afterglow was adapted to study ion kineties [85]. This represented a major advanee sinee the flowing afterglow is a thennal deviee under most situations and previous instruments were not. Smee that time, many iterations of the ion-moleeule flow tube have been developed and it is an extremely flexible method for studying ion-moleeule reaetions [86, 87, 88, 89, 90, 91 and 92]. [Pg.808]

As with most methods for studying ion-molecule kinetics and dynamics, numerous variations exist. For low-energy processes, the collision cell can be replaced with a molecular beam perpendicular to the ion beam [106]. This greatly reduces the thennal energy spread of the reactant neutral. Another approach for low energies is to use a merged beam [103]. In this system the supersonic expansion is aimed at the tluoat of the octopole, and the ions are passed tluough... [Pg.812]

Calorimetry is the basic experimental method employed in thennochemistry and thennal physics which enables the measurement of the difference in the energy U or enthalpy //of a system as a result of some process being done on the system. The instrument that is used to measure this energy or enthalpy difference (At/ or AH) is called a calorimeter. In the first section the relationships between the thennodynamic fiinctions and calorunetry are established. The second section gives a general classification of calorimeters in tenns of the principle of operation. The third section describes selected calorimeters used to measure thennodynamic properties such as heat capacity, enthalpies of phase change, reaction, solution and adsorption. [Pg.1899]

One method, simple to implement and reliable, is to periodically reselect atomic velocities at random from the Maxwell-Boltzmaim distribution [79]. This is rather like an occasional random coupling with a thennal bath. The resampling may be done to individual atoms, or to the entire system some giudance on the reselection frequency may be found in [79]. [Pg.2261]

The concept of macroscopic kinetics avoids the difficulties of microscopic kinetics [46, 47] This method allows a very compact description of different non-thennal plasma chemical reactors working with continuous gas flows or closed reactor systems. The state of the plasma chemical reaction is investigated, not in the active plasma zone, but... [Pg.2810]

These theoretical descriptions of the thennal etching reaction between F2 and Si(lOO) have been reviewed in some detail in the context of ah initio methods in surface chemistry [60]. [Pg.2936]

Another popular approach to the isothennal (canonical) MD method was shown by Nose [25]. This method for treating the dynamics of a system in contact with a thennal reservoir is to include a degree of freedom that represents that reservoir, so that one can perform deterministic MD at constant temperature by refonnulating the Lagrangian equations of motion for this extended system. We can describe the Nose approach as an illustration of an extended Lagrangian method. Energy is allowed to flow dynamically from the reservoir to the system and back the reservoir has a certain thermal inertia associated with it. However, it is now more common to use the Nose scheme in the implementation of Hoover [26]. [Pg.59]

The thennal decarboxylation of malonic acid derivatives is the last step in a multistep synthesis of caiboxylic acids known as the malonic ester synthesis. This synthetic method will be described in Section 21.7. [Pg.818]

Bahrami, A.R., Fam, I.M., Donaldson, J. Development of a thennal desorption method for the analysis of particle associated polycyclic aromatic hydrocarbons in ambient air. Int. J. Environ. Sci. Technol. 1, 165-169 (2004)... [Pg.426]

In summary, it has been demonstrated that the transient grating technique can be used to determine thennal physical properties (thermal diffusivity and thermal conductivity) of ILs. The technique has relatively high precision, namely relative errors are about 1%. It also has relatively high accuracy thermal conductivity values of ILs determined by this method agree, within 1% with values previously determined by other workers. More importantly. [Pg.100]

In 55% of the cases, the accidents could have been foreseen by use of risk analysis, and in 35% of the cases by thennal stability testing. Different methods of stability testing were evaluated comparatively during the investigation of a runaway exothermic reaction which occurred during the preparation of a component mixture for a sealing composition in a 1200 1 reactor only DSC was effective in identifying the cause of the hazard. [Pg.2409]

In concluding this chapter, we must reemphasize that, while quantitative structure-property relationships for the thermal conductivities of amorphous polymers are useful indicators of the general trends as a function of the polymer stmcture, they must nonetheless be used with some caution in practical applications, since factors such as crystallinity, orientation, additives and/or impurities can modify the thermal conductivity by a very considerable amount, and differences among measurement methods introduce further uncertainties. The demand for and the limited availability of consistent thennal conductivity data for polymers were discussed in a concise review article [18] which is recommended as an indicator of the need for caution when utilizing either published experimental or predicted values of this property in practical applications. [Pg.590]

The process for the thennal sensor network is as follows. Organic diodes, to be used as sheet-type thermal sensors, are manufactured on an ITO-coated PEN film. A 30-mn thick p-type semiconductor of copper phthalocyanine (CuPc) and a 50-nm thick n-type semiconductor of 3,4,9,10-perylene-tetracarboxylic-diimide (PTCDI) are deposited by vacuum sublimation. A 150-mn thick gold film is then deposited to form cathode electrodes having an area of 0.19 mm. The film with the organic diodes is coated with a 2-pm thick parylene layer and the electronic interconnections are made by the method similar to that mentioned before. The diode film is also mechanically processed to form net-shaped structures. Finally, to complete the thermal sensor network, we laminated the transistor and diode net films together with silver paste patterned by a microdispenser. This is shown in Figure 6.3.11. [Pg.540]

Ifie equation is most conveniently solved by the method of Laplace transforms, used for the solution of the unsteady state thennal conduction problem in Chapter 9. [Pg.603]

Additionally, variants have been developed that combine the in situ burning with other thennal EOR methods. The in situ combustion method can also be employed as a means of treatment, such as the stimulation, of the bottomhole zone of oil wells. [Pg.103]

Classify the following reactions by the component analysis method (e.g., n s + ala + ) Decide whether the reaction as shown is thennally allowed. Show clearly the orbitals on which you base your analysis. [Pg.290]

Test Methods For The Thennal Stability Assessment Of Substances And Mixtures... [Pg.28]

ISO 2582. Cork and cork products—Determination of thennal conducti ity—hot plate method. 1978. [Pg.405]

Standard test method for assignment of the glass-transition temperatures hy differential scanning calorimetry or differential-thennal analysis Methods of test for determination of glass-transition temperature of electrical insulating materials... [Pg.362]


See other pages where Thennal methods is mentioned: [Pg.1916]    [Pg.877]    [Pg.882]    [Pg.1916]    [Pg.877]    [Pg.882]    [Pg.1824]    [Pg.1961]    [Pg.2564]    [Pg.2811]    [Pg.2936]    [Pg.154]    [Pg.120]    [Pg.209]    [Pg.205]    [Pg.700]    [Pg.64]    [Pg.190]    [Pg.396]    [Pg.195]    [Pg.2170]    [Pg.254]    [Pg.355]    [Pg.75]    [Pg.291]    [Pg.463]    [Pg.158]    [Pg.212]   
See also in sourсe #XX -- [ Pg.116 ]




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