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Their Types

Examine now the symmetries of these different types of vibration. For this purpose, a new type of basis set is used. Since we are interested in the changes of the geometrical parameters, these changes are an obvious choice for basis set. The geometrical parameters are also called internal coordinates, and the basis is the displacement of these internal coordinates. [Pg.213]

Let us continue with the water molecule and determine the symmetry of its stretching modes. The molecule has two O-H bonds, so the basis will be the changes of these O-H bonds. The representation of this basis set is [Pg.213]

This means that the stretching of the O-H bonds contributes to the normal modes of A, and symmetry. (We shall later see that these are the symmetric and antisymmetric stretches, respectively.) [Pg.213]

The third internal coordinate which can be considered in the water molecule is the bond angle, H-O-H. Its change will be the bending mode. All symmetry operations leave this basis unchanged, so the representation is [Pg.214]

Modes of different symmetry never mix, even if they are close in energy. (This is a general rule which will have its analogous version for the transitions among electronic states as will be seen later in Chapters 6 and 7.) [Pg.214]

The normal modes can usually—though not always—be associated with a certain kind of motion. Those connected mainly with changes in bond lengths are the stretching modes. The ones connected mainly with changes of bond angles are the deformation modes. These may be mainly either in-plane or out-of-plane deformation modes. The simplest deformation mode is the bending mode. [Pg.224]


Non-fuel petroleum products cover an extremely wide range and are distinguished as much by their nature and physical aspects as by their types of application. [Pg.271]

Operating Labor Centrifuges run the gamut from completely manual control to fully automated operation. For the former, one operator can run sever centrifuges, depending on their type and the apphcation. Fully automatic centrifuges usually require little dirert operation attention. [Pg.1743]

A eompany will typieally eategorize its suppliers aeeording to their type of operation, for example ... [Pg.273]

The values of eonstant C and the exponents a, b, and e depend on the type of agitator, whether baffles are used and their type, and whether the transfer is via the vessel wall or to eoils. Baffles are normally used in most applieations, and the values of a, b and e in the literamre are 2/3, 1/3, and 0.14 respeetively. Tables 7-14 and 7-15 give typieal eorrelations for various agitator types. [Pg.620]

The SCBD depends on the MW, i.e., iow-MW fraction consists of a large number of SCBs as compared with high-MW fractions in LLDPE. The results of fractionation of two LLDPEs, differing in their type and content of comonomer but having the same density and... [Pg.279]

Record—The elements (fields) may be of different types and may be accessed at random fields and their types are assigned at declaration and may not be changed field values are assigned as are variable values. [Pg.124]

Properties of crude oils vary considerably according to their types. Table 1-5 lists the analyses of some crudes from different origins. [Pg.23]

No proposal for a laboratory ventilation system should be requested without a thorough study of the work to be performed. A once-through system may not always be required. The manager of a research laboratory, working closely with a designer, discovered that 50% recirculation would be permissible in their new building. While this is even less than in offices and stores, it proved to be adequate for their type of work. He would not recommend this ratio for other laboratories without a careful study. [Pg.33]

Based on present knowledge, contaminants, by virtue of their type or number, should not present a potential health hazard to patients when used. [Pg.383]

The second chemotype (their Type 1) had, in addition to the Type 0 array, substantial amounts of a-longipinene [297] and an unidentified sesquiterpene alcohol. The third chemotype (their Type 2) was distinguished by the presence of, among other compounds, cedrene isomers, [a-cedrene is shown as 298], and large amounts of the isomeric sesquiterpene alcohols a-acorenol [294] and its P-isomer [295]. The acora-diene isomers [295 and 296] were also identified. Some geographic patterning was observed in the Type 0 chemotype when the data were subjected to numerical analysis a trend in the reduction of caryophyllene content was revealed in a west to east direction. The data sets for Types 1 and 2 were too small to allow for similar analysis. [Pg.168]

The foregoing text highlights the fact that at the interface between electrolytic solutions of different concentrations (or between two different electrolytes at the same concentration) there originates a liquid junction potential (also known as diffusion potential). The reason for this potential lies in the fact that the rates of diffusion of ions are a function of their type and of their concentration. For example, in the case of a junction between two concentrations of a binary electrolyte (e.g., NaOH, HC1), the two different types of ion diffuse at different rates from the stronger to the weaker solution. Hence, there arises an excess of ions of one type, and a deficit of ions of the other type on opposite sides of the liquid junction. The resultant uneven distribution of electric charges constitutes a potential difference between the two solutions, and this acts in such a way as to retard the faster ion and to accelerate the slower. In this way an equilibrium is soon reached, and a steady potential difference is set up across the boundary between the solutions. Once the steady potential difference is attained, no further net charge transfer occurs across the liquid junction and the different types of ion diffuse at the same rate. [Pg.629]

From an engineering perspective, recycled materials should be used in such a manner that the expected performance of the product will not be compromised. Waste and byproduct materials, however, differ vastly in their types and properties and, as a result, in the end-use applications for which they may be suited. Experience and knowledge regarding the use of these materials vary from material to material as well as from facility to facility. To recover these materials for potential use, engineers, researchers, generators, and regulators need to be aware of the properties of the materials, how they can be used, and what limitations may be associated with their use. [Pg.192]

Various sequential dissolution protocols have been developed by different research groups in order to accommodate their types of soils, experimental conditions, and objectives. This makes it difficult to compare the results with different procedures. We compared two SSD procedures for humid zone and arid zone soils, developed by German and Israeli soil scientists, respectively, based on aggressiveness of extractants, their specificity and selectivity, completeness of phase-extraction by each extractant from defined phases and their effects on subsequent fractions. We also appraised the applicability as well as the limitations of each procedure under different conditions. [Pg.122]

The enormous significance of olfaction for the interaction of humans with their environment is evident. According to their type and condition, most objects or processes give off a typical smell, caused by fluids and solid materials containing... [Pg.52]

Secondly, we assume that reactions can be treated according to their type, so reaction order is introduced and discussed in terms of the way in which concentrations vary with time in a manner that characterizes that order. [Pg.349]

Precise description of behavior needs an abstract model of the state of any correct implementation and of input or output parameters. Catalysis uses a type model for this. Types specify behavior in terms of the effect of operations on conceptual attributes. For a simple type, these attributes and their types are listed textually more-complex types may have a type model drawn graphically and even factored into separate drawings. [Pg.59]

An operation can be specified in the style detailed earlier in this chapter. You can refer to the old and new values of the internal variables (and to attributes of their types, and of the attributes types, and so on). [Pg.176]

Always be clear about who the document is for and why it has been created. A document, even of an implementation, that is meant for a client of the implementation should not bother with showing internal implementation decisions. Instead, it should show only the types that the client needs to know about along with their type specifications. [Pg.231]

On a larger scale, more-complex models can be used to represent the types of whole systems or components and are usually shown pictorially. In an abstract model, the attributes and their types are chosen to help specify the operations on the component as a whole and, according to good object-oriented analysis practice, are based on a model of the domain. However, anyone who has been involved in practical OOD is aware that the design phase introduces all sorts of extra classes as patterns are applied to help generalize the design, make it more efficient, distribute the design, provide persistence or a GUI, and so on. But we can still retrieve the abstract model from any tme implementation in the same way as for the simpler models. [Pg.246]

Minimize the number of explicit mentions of other classes. Refer to other objects by their types or interfaces. When you need to instantiate another object, use a factory method rather than directly name the class to instantiate. [Pg.659]

In this chapter chromatographic bioreactors are considered as chromatographic reactors where the reaction is catalyzed by an enzyme or enzyme system, which can be present in pure form or as a cell component. The enzyme can be immobilized on the matrix or it can be dissolved in a liquid phase. Therefore, the reaction can take place in either phase. Several different bioreactions were performed in chromatographic reactors of different types. In the following part some pertinent examples are presented according to their type of reaction. [Pg.196]

However, it has to be borne in mind that salts added to the mobile phase, their type and concentration, and the pH can influence the retention order. This technique can be modified by the application of a so-called suppressor column. The suppressor column exchanges the counter-ion of the analyte after the separation column, enhancing in this manner the sensitivity of conductometric detection of analyte ions. [Pg.20]

The authors wish to thank Ms. Cheryl Beyer, Ginger Marlow, and Pat Kelley for their typing and clerical assistance in planning for the symposium and book. Activities of the editors related to the symposium... [Pg.1]


See other pages where Their Types is mentioned: [Pg.328]    [Pg.266]    [Pg.79]    [Pg.485]    [Pg.175]    [Pg.419]    [Pg.72]    [Pg.175]    [Pg.115]    [Pg.34]    [Pg.742]    [Pg.386]    [Pg.196]    [Pg.32]    [Pg.157]    [Pg.66]    [Pg.491]    [Pg.154]    [Pg.162]    [Pg.149]    [Pg.144]    [Pg.145]    [Pg.95]    [Pg.49]    [Pg.111]    [Pg.186]    [Pg.487]    [Pg.248]   


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