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Third step

The third step follows after interchanging summation and integration and recognizing drat the N(N - l)/2 tenns in the sum are identical. The pressure follows from the relation... [Pg.450]

In a third step the S-matrix is related to state-selected reaction cross sections a., in principle observable in beam scattering experiments [28, 29, 30, 31, 32, 33, 34 and 35], by the fiindamental equation of scattering theory... [Pg.773]

On the atomic level, etching is composed of several steps diflfiision of the etch molecules to the surface, adsorption to the surface, subsequent reaction with the surface and, finally, removal of the reaction products. The third step, that of reaction between the etchant and the surface, is of considerable interest to the understanding of surface reactions on an atomic scale. In recent years, STM has given considerable insight into the nature of etching reactions at surfaces. The following discussion will focus on the etching of silicon surfaces [28]. [Pg.934]

The first step consists of the molecular adsorption of CO. The second step is the dissociation of O2 to yield two adsorbed oxygen atoms. The third step is the reaction of an adsorbed CO molecule with an adsorbed oxygen atom to fonn a CO2 molecule that, at room temperature and higher, desorbs upon fomiation. To simplify matters, this desorption step is not included. This sequence of steps depicts a Langmuir-Hinshelwood mechanism, whereby reaction occurs between two adsorbed species (as opposed to an Eley-Rideal mechanism, whereby reaction occurs between one adsorbed species and one gas phase species). The role of surface science studies in fomuilating the CO oxidation mechanism was prominent. [Pg.953]

Fig. 5.5 The first few steps of the simplex algorithm with the function + 2i/. The initial simplex corresponds to the triangle 123. Point 2 has the largest value of the function and the next simplex is the triangle 134. The simplex for tire third step is 145. Fig. 5.5 The first few steps of the simplex algorithm with the function + 2i/. The initial simplex corresponds to the triangle 123. Point 2 has the largest value of the function and the next simplex is the triangle 134. The simplex for tire third step is 145.
Fig. 10.20 Schematic illustration of the creation of a multiple sequence alignment for five sequences A-E. In the fi step sequences C and E are aligned. In the second step sequences A and D are aligned. In the third step the pair Cl aligned with the pair AD. Finally, the quartet CEAD is aligned with B. Fig. 10.20 Schematic illustration of the creation of a multiple sequence alignment for five sequences A-E. In the fi step sequences C and E are aligned. In the second step sequences A and D are aligned. In the third step the pair Cl aligned with the pair AD. Finally, the quartet CEAD is aligned with B.
In a third step, the anhydrobase reacts on the carbon which is the most sensitive to nucleophilic attack. The unstable intermediate 23 splits into aminothiophenol and trimethine thiazolocyanine 124). [Pg.43]

The synthesis of these disubstituied thioureas takes place in three steps. First the alkyl bromide is prepared by the action of hydrobromic acid on the corresponding alcohol (518). Then the dialkylcyanamide is obtained by treatment at 25°C with calcium cyanamide. The yields are of the order of 30 to 60%. Thioureas are obtained in a third step from the cyanamide by reaction at 40 C with HjS in the presence of pyridine. Yields ranged from 57 to 90% (518),... [Pg.248]

In the second step, a papermaking method is also used for the fine fibers, less than 0.1 tex (1 den). This process is usually followed by a high pressure water jet process instead of the third step. In the fourth step, to obtain the required properties in specific appHcations, a polyurethane is selected out of the segmented polyurethanes, which comprises a polymer diol, a diisocyanate, and a chain extender (see Urethane polymers). A DMF—water bath for coagulation is also controlled to create the adequate pore stmcture in combination with fibers. [Pg.94]

In the third step, L-sorbose is reacted with acetone and excess sulfuric acid at low temperatures. The sorbose dissolves on conversion into the 2,3-mono-O-isopropjhdene-L-sorbose (2,3 monoacetone-L-sorbose) (MAS), and 2,3 4,6-bis-0-isoprop5hdene-a-L-sorbofuranose... [Pg.16]

The third step is hydrolysis of the N-phosphorylated amidines which is carried out by either acid or alkali depending on the substrate. [Pg.194]

All current comparative modeling methods consist of four sequential steps (Fig. 2) [5,6]. The first step is to identify the proteins with known 3D structures that are related to the target sequence. The second step is to align them with the target sequence and pick those known structures that will be used as templates. The third step is to build the model... [Pg.275]

Let us further specify that the first step is a very rapid but unfavorable equilibrium and that A3 i.e., the second step is slow relative to the third step. Under these circumstances,... [Pg.194]

Although conditions under which each of the first two steps is rate-determining have been recognized, the third step is usually very fast. [Pg.572]

In our third step, we convert the compositions to a kg-moles-per-second basis. For this example (as well as many common industry cases), the ideal gas law can be used n = PV/RT, where n = number of moles... [Pg.373]

Most heat transfer processes used in production facilities involve combinations of conduction and convection ti ansfer processes. For example, in heat exchangers the transfer of heat energy from the hot fluid to the coLl fluid involves tliree steps. First, the heat energy is transferred from the luH fluid to the exchanger tube, then through the exchanger tube wall, ctud finally from the tube wall to the cold fluid. The first and third steps are convection transfer processes, while the second step is conduction process. [Pg.11]

The third step is to select a rc icw leant. The learn is usually composed of two or three members that have combined c.xpcricnce in the process to be studied, knowledge in the consequence field, and c.xpcricnce in general hazmd evaluirlion. If the learn is inc.xpcricrtccd, results may be incomplete or inconccl. [Pg.443]

FIGURE 16.27 A mechanism for the aspartic proteases. In the first step, two concerted proton transfers facilitate nucleophilic attack of water on the substrate carbonyl carbon. In the third step, one aspartate residue (Asp" " in pepsin) accepts a proton from one of the hydroxyl groups of the amine dihydrate, and the other aspartate (Asp" ) donates a proton to the nitrogen of the departing amine. [Pg.521]

FIGURE 20.28 The glyoxylate cycle. The first two steps are identical to TCA cycle reactions. The third step bypasses the C09-evolving steps of the TCA cycle to produce snc-cinate and glyoxylate. The malate synthase reaction forms malate from glyoxylate and another acetyl-CoA. The result is that one torn of the cycle consumes one oxaloacetate and two acetyl-CoA molecnles bnt produces two molecnles of oxaloacetate. The net for this cycle is one oxaloacetate from two acetyl-CoA molecnles. [Pg.669]


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Single-step, third-order reaction

Step 10 Creation of the second, third, and higher level branches

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