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Breaking down the problem

It is instructive to first consider the forward problem from the reactor to the feature, ignoring the coupling back into the reactor. Because of the disparity of the length scales involved, it helps to break down the problem into several pieces. An approach proposed by Economou and Alkire [89] is shown in Fig. 38. The near wafer space is separated into two regions. Region I and Region II. Region I contains the... [Pg.307]

The slurry reactor analysis given above employed the concept of an overall effectiveness factor. It is informative to break down the problem into analysis of individual phase effectiveness factors assembled together as was done for the three-phase fluid-bed model. Equating the rates of the individual steps in a manner similar to... [Pg.600]

In an alternative approach we break down the problem into three steps (1) Convert 63 miles to a distance in meters (2) convert 1 hour to a time in seconds and (3) express the speed as a ratio of distance over time. [Pg.1336]

This approach to the overall problem breaks down the design procedure into two steps of first determining the best nonintegrated sequence and then heat integrating. This assumes that the two problems of distillation sequencing... [Pg.451]

When studying for the tests, look over the old problem sets, do the problems from the back of the book, and utilize the website Time management is crucial. Break down the studying. Do not cram. Orgo tests are on Fridays. It helps if you divide the material and study it over the course of the week. [Pg.9]

As centrifugation proceeds, filaments of suspension may break through the interface between the suspension and the separating liquid and stream down. The problem is alleviated or diminished by more sophisticated techniques, such as the three-layer method [20] or the gradient technique. [Pg.32]

In each class the problem may be resolved into two essential parts (i) the breakdown of the organic compound under appropriate conditions to give a quantitative yield of fluoride ions in aqueous solution, and (ii) the determination of the concentration of these fluoride ions. Methods of breaking down the organic compounds were examined and the procedure adopted for the phosphorofluoridate was different from that used for the fluoroacetate series. From both, however, sodium fluoride was obtained as the breakdown product containing all the fluorine present. After numerous preliminary experiments we came to the conclusion that on the macro-scale a very convenient method of determining the quantity of fluoride ions in the products was by precipitation as lead chlorofluoride,2 PbCIF, which was then dissolved in dilute nitric acid and the chloride was determined by the Volhard method and calculated to the equivalent amount of fluorine. We determined carefully the conditions for the quantitative precipitation of lead chlorofluoride. [Pg.219]

The year 1954 is a landmark in Prigogine s research in thermodynamics for the first time he ventures to break down the barrier of linearity. As in all sciences, the simplest problems occur when one studies the phenomena that happen in the neighborhood of a known reference state. The tools necessary for this study have been handed down to us by the mathematicians of the nineteenth century linear analysis, a complete, simple and elegant formalism, offering the solution of all problems in this realm. Unfortunately, when applied to physical problems, one must take into account that its validity range is very limited. [Pg.11]

Figures 20a and 20b are SEM micrographs of dielectric cracks from a top view and from a cross-sectional view. The root cause was determined to be poor stress control in the TEOS film, not the CMP process. However, this problem may not have been as serious without CMP (i.e., CMP may exacerbate the problem). For CMP, the dielectric film must be highly compressive. If a film is tensile or not compressive enough, the overwhelming down force of CMP will impart significant shear stress, enough to break down the film. This is particularly true for the areas above the metal lines at ILD levels, where the surface has an abrupt step height in topography. A crack can start from the concave corner of the step and travel to the corner of a metal line, as shown in Fig. 20c. Figures 20a and 20b are SEM micrographs of dielectric cracks from a top view and from a cross-sectional view. The root cause was determined to be poor stress control in the TEOS film, not the CMP process. However, this problem may not have been as serious without CMP (i.e., CMP may exacerbate the problem). For CMP, the dielectric film must be highly compressive. If a film is tensile or not compressive enough, the overwhelming down force of CMP will impart significant shear stress, enough to break down the film. This is particularly true for the areas above the metal lines at ILD levels, where the surface has an abrupt step height in topography. A crack can start from the concave corner of the step and travel to the corner of a metal line, as shown in Fig. 20c.
In order to circumvent this problem and also to make it easier to visualize the actual distribution or electrons within the atom, it is common to break down the wave function, vfJ, into three parts, each or which is a function of but a single variable. It is most convenient to use polar coordinates, so one obtains... [Pg.17]

Richard Koehn I couldn t agree more that it is a question of trust. The problem is always when that trust breaks down. The real problem is the lack of recourse. [Pg.105]

The first step in using the AHP to analyze a decision problem is to hierarchically break down the decision problem (objective) into its constituent components and identify the alternatives to be evaluated. The resulting hierarchy consists of the overall objective (goal) and one or more levels of sub-objectives. The alternatives to be evaluated are added at the lowest level of the hierarchy. According to Saaty (1980, pp. 79-83) a cluster should not contain more than 7 elements because results from psychological tests show that 1+1-2 are the maximum number of elements a person can effectively compare simultaneously. [Pg.138]

One problem with long-term inhalant abuse is that it can break down myelin in the body, according to a NIDA report. Myelin is a fatty tissue that surrounds many of the body s nerve cells called neurons. The nerve cells in the brain and spinal cord are like a command central for the body. They transmit messages that control just about everything the body does. If the myelin breaks down, the nerve cells may not be able to transmit messages. [Pg.48]

There are many drugs that increase the rate of the liver s metabolism. More commonly used medications that fall into this category include rifampin, which is used to treat tuberculosis, and dilantin, phenytoin, and carbamazepine, which are medications commonly used to treat seizures and epilepsy. Chronic alcohol abuse also speeds up the metabolism of the liver. Since all of these substances cause the liver to break down methadone faster then it normally would, one way to correct the problem would be to increase the dose of methadone or break down the dose into several smaller doses given throughout the day. This should only be done on a physician s advice. [Pg.329]


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Breaking down

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