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The First Requirement

In order for the polynomial to touch the nodes, a cubic polynomial must be constructed so that at point Xo the polynomial provides a result that is equal toj/ v.This is very easy to achieve. Since Xis equal to zero at its starting point, the polynomial takes the following form  [Pg.101]

So as long as is equal to then our polynomial will touch the node at X- [Pg.101]

In order for the polynomial to touch the second node, the node at point Xtv+1, then the polynomial must take the following form at pointer [Pg.101]

It is worth noting that at this point in our process we do not know what the values of a, b, or c are. These will be derived later from our other requirements. [Pg.101]


The first requirement is a source of infrared radiation that emits all frequencies of the spectral range being studied. This polychromatic beam is analyzed by a monochromator, formerly a system of prisms, today diffraction gratings. The movement of the monochromator causes the spectrum from the source to scan across an exit slit onto the detector. This kind of spectrometer in which the range of wavelengths is swept as a function of time and monochromator movement is called the dispersive type. [Pg.57]

The first requirement is the definition of a low-dimensional space of reaction coordinates that still captures the essential dynamics of the processes we consider. Motions in the perpendicular null space should have irrelevant detail and equilibrate fast, preferably on a time scale that is separated from the time scale of the essential motions. Motions in the two spaces are separated much like is done in the Born-Oppenheimer approximation. The average influence of the fast motions on the essential degrees of freedom must be taken into account this concerns (i) correlations with positions expressed in a potential of mean force, (ii) correlations with velocities expressed in frictional terms, and iit) an uncorrelated remainder that can be modeled by stochastic terms. Of course, this scheme is the general idea behind the well-known Langevin and Brownian dynamics. [Pg.20]

In absorption spectroscopy a beam of electromagnetic radiation passes through a sample. Much of the radiation is transmitted without a loss in intensity. At selected frequencies, however, the radiation s intensity is attenuated. This process of attenuation is called absorption. Two general requirements must be met if an analyte is to absorb electromagnetic radiation. The first requirement is that there must be a mechanism by which the radiation s electric field or magnetic field interacts with the analyte. For ultraviolet and visible radiation, this interaction involves the electronic energy of valence electrons. A chemical bond s vibrational energy is altered by the absorbance of infrared radiation. A more detailed treatment of this interaction, and its importance in deter-... [Pg.380]

In this section we discuss the initiation step of free-radical polymerization. This discussion is centered around initiators and their decomposition behavior. The first requirement for an initiator is that it be a source of free radicals. In addition, the radicals must be produced at an acceptable rate at convenient temperatures have the required solubility behavior transfer their activity to... [Pg.349]

Generalizations. Several generalizations can be made regarding taste (16,26). A substance must be in water solution, eg, the Hquid bathing the tongue (sahva), to have taste. Water solubiUty is the first requirement of the taste stimulus (12). The typical stimuli are concentrated aqueous solution in contrast with the Hpid-soluble substances which act as stimuli for olfaction (22). Many taste substances are hydrophilic, nonvolatile molecules (15). Taste detection thresholds for lipophilic molecules tend to be lower than those of their hydrophilic counterparts (16). [Pg.11]

Requirements. Requirements for dental implant materials are the same as those for orthopedic uses. The first requirement is that the material used ia the implant must be biocompatible and not cause any adverse reaction ia the body. The material must be able to withstand the environment of the body, and not degrade and be unable to perform the iatended function. [Pg.495]

Composition Control The first requirement for successflil control of a chemical reactor is to establish the proper stoichiometry, that is, to control the flow rates of the reac tants in the proportions needed... [Pg.747]

Selection of a name for a specific compound is heavily influenced by the purpose at hand communication to a general audience, communication with specialists, or storage/retrieval through archival indexes. The first requires the simplest rules possible the second requires the shortest names possible and the third requires rigid adherence to a set of rules that will reliably generate a unique name. The name chosen may be different for each situation, although that is not necessarily so. [Pg.35]

From what we have said so far it should be obvious that the first requirement that we should look for in choosing materials that are resistant to creep is that they should have high melting (or softening) temperatures. If the material can then be used at less than 0.3 of its melting temperature creep will not be a problem. If it has to be used above this temperature, various alloying procedures can be used to increase creep resistance. To... [Pg.177]

The first requirement for threading is to have a database of all the known different protein folds. Eisenberg has used his own library of about 800 folds, which represents a minimally redundant set of the more than 6000 structures deposited at the Protein Data Bank. Other groups use databases available on the World Wide Web, where the folds are hierarchically ordered according to structural and functional similarities, such as SCOP, designed by Alexey Murzin and Cyrus Chothia in Cambridge, UK. [Pg.353]

The first requirement must be to specify carefully the operational requirements of the item to be produced and of the material(s) to be used in its construction. This is seldom easy and is usually the most difficult part of the selection process. The most common factors to be considered are ... [Pg.891]

For a room temperature eontrol system, the first requirement is to deteet or sense ehanges in room temperature. The seeond requirement is to eontrol or vary the energy output from the gas fire, if the sensed room temperature is different from the desired room temperature. In general, a system that is designed to eontrol the output of a plant must eontain at least one sensor and eontroller as shown in Figure 1.5. [Pg.5]

The first requirement of the grid is that it distribute gas evenly across the fluid bed. This is accomplished by having a large number of holes and a high pressure drop across the grid. The high pressure drop assures that flow will be uniform through all holes and that flow stabihty will not be much influenced by behavior of the fluid bed. [Pg.44]

This requirement appears low down in the list of requirements and should ideally have been the first requirement that the standard addressed under design control. Until you have a design input you cannot carry out your design and development planning. [Pg.245]

The precision of SEC must be established before a comparison of columns and calibration standards can be made. Consistency in flow rate or elution time is the first requirement to obtain precision in SEC. Consistency in flow rate or elution time can be monitored by the elution time of the PEO standards, which are run before and after the samples. Elution time or flow rate can be considered consistent if the elution times of the PEO standards before and after the samples agree within 0.1 min. [Pg.502]

The principles of statistical mechanics can be applied to a dynamical systeni provided that it obeys Louiville s Theorem (that is, it preserves volumes in phase space) and that its energy remains constant. The first requirement is easy since all reversible rules 4>r define bijective mappings of the phase space volume... [Pg.378]

This definition outlines in very broad terms the scope of analytical chemistry. When a completely unknown sample is presented to an analyst, the first requirement is usually to ascertain what substances are present in it. This fundamental problem may sometimes be encountered in the modified form of deciding what impurities are present in a given sample, or perhaps of confirming that certain specified impurities are absent. The solution of such problems lies within the province of qualitative analysis and is outside the scope of the present volume. [Pg.3]

This allows the pressure, which has significance only when the fluid experiencing it is named, to be replaced by a dimensionless group of properties which has significance for all fluids. Thus, the first requirement in constructing a model of a system is that the inlet pressures should be selected so that the density ratio of the two phases in the model is the same as that in the system... [Pg.281]

Another important consideration is the comparison between gaseous and crystalline sulfoxides and sulfones. Such a comparison may yield information about intermolecular interactions in the crystal1. Unfortunately, very few data are yet available for confident use in such comparisons. The first requirement is, of course, that the same compound has been investigated both in the gaseous state and in the crystal. In addition, it is necessary that all the structural data correspond to the same physical meaning (cf. Reference 1). When these conditions are fulfilled, interesting conclusions2 may be reached on the basis of even small differences. [Pg.34]

At this point several assumptions must be made. The first requires the absence of isotope effects on the rate of Reaction O—i.e., the rate constants of Reactions O, U + V, and W are identical this is termed k, and the plausibility of the assumption is indicated by the absence of isotope effects on the rate constant of Reaction I. The second assumption requires that in proton transfer reactions like Reaction O, a deuteron... [Pg.150]

The first requirement, on the other hand, posed formidabie chemicai probiems. Three nuciides can serve as nuciear 239 233 235... [Pg.1584]

The most critical element in melt-growth of single crystals is the container, or crucible. The first requirement for selection of a suitable crucible is that the crucible does not react with the melt. The second is... [Pg.256]

While the discovery of the catalytic properties of zeolites was driven by the desire to improve industrial prcKessing, the development of emission control catalysts was necessitated by governmental fiat. The first requirement was for 90+% removal of CO and of hydrocarbons, a goal which could not be met by oxidation with base metal oxides. To achieve the required spedfications during automobile operations, it was necessary to develop supported platinum catalysts. Originally the support was alumina in pellet form. Later platinum on cordierite was used in honeycomb form, containing 200-400 square channels per square inch. [Pg.71]

Two additional requirements are specific to the analysis of residues in food. The first requirement depends on the LOQ to be achieved (see Table 5). [Pg.29]

Let s discuss the first requirement, a criterion for us. We notice that it is not requested that the model is validated. Validation is a formal process, which takes many years. The formal validation process of a QSAR model would end after REACH probably. [Pg.85]

Much of the information about proteomics techniques and technologies included here comes from the Chembytes ezine article written by Michael Dunn and available in 2001 on the website http //www.chemsoc.org/chembytes/ezine/1998/ dunn.htm. The first requirement for proteome analysis, also known as protein... [Pg.34]


See other pages where The First Requirement is mentioned: [Pg.250]    [Pg.426]    [Pg.466]    [Pg.27]    [Pg.437]    [Pg.680]    [Pg.17]    [Pg.893]    [Pg.99]    [Pg.12]    [Pg.241]    [Pg.517]    [Pg.393]    [Pg.518]    [Pg.118]    [Pg.970]    [Pg.251]    [Pg.172]    [Pg.210]    [Pg.462]    [Pg.54]    [Pg.55]    [Pg.92]    [Pg.74]   


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