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Locations property

Three Hanford sediments were used in the sorption studies. Each of these sediments contained significant quartz, feldspar, vermiculite, mica, and montmorillonite and were typical of the Hanford sediment in which the HLW tanks are located. Properties of the sediments used are given in Table H. [Pg.98]

Carbonate rocks are not normally transported over long distances, and we find carbonate reservoir rocks mostly at the location of origin, in situ . They are usually the product of marine organisms. However, carbonates are often severely affected by diagenetic processes. A more detailed description of altered carbonates and their reservoir properties is given below in the description of diagenesis . [Pg.78]

Figure 5.37 depicts the basic set up of a wireline logging operation. A sonde is lowered downhole after the drill string has been removed. The sonde is connected via an insulated and reinforced electrical cable to a winch unit at the surface. At a speed of about 600m per hour the cable Is spooled upward and the sonde continuously records formation properties like natural gamma ray radiation, formation resistivity or formation density. The measured data is sent through the cable and is recorded and processed in a sophisticated logging unita the surface. Offshore, this unit will be located in a cabin, while on land it is truck mounted. In either situation data can be transmitted in real time via satellite to company headquarters if required. [Pg.131]

Here, the distances x and a are relative to planes A and B located far enough from the surface region so that bulk phase properties prevail. The actual amount of component i present in the region between A and B will be... [Pg.72]

IHP) (the Helmholtz condenser formula is used in connection with it), located at the surface of the layer of Stem adsorbed ions, and an outer Helmholtz plane (OHP), located on the plane of centers of the next layer of ions marking the beginning of the diffuse layer. These planes, marked IHP and OHP in Fig. V-3 are merely planes of average electrical property the actual local potentials, if they could be measured, must vary wildly between locations where there is an adsorbed ion and places where only water resides on the surface. For liquid surfaces, discussed in Section V-7C, the interface will not be smooth due to thermal waves (Section IV-3). Sweeney and co-workers applied gradient theory (see Chapter III) to model the electric double layer and interfacial tension of a hydrocarbon-aqueous electrolyte interface [27]. [Pg.179]

Finally, in the case of solids, there is the difficulty that surface atoms and molecules differ in their properties from one location to another. The discussion in Section VII-4 made clear the variety of surface heterogeneities possible in the case of a solid. Those measurements that depend on the state of surface atoms or molecules will generally be influenced differently by such heterogeneities. Different methods of measuring surface area will thus often not only give different absolute values, but may also give different relative values for a series of solids. [Pg.574]

A feature of a critical point, line, or surface is that it is located where divergences of various properties, in particular correlation lengths, occur. Moreover it is reasonable to assume that at such a point there is always an order parameter that is zero on one side of the transition and tliat becomes nonzero on the other side. Nothing of this sort occurs at a first-order transition, even the gradual liquid-gas transition shown in figure A2.5.3 and figure A2.5.4. [Pg.649]

Figure Bl.6.1 Equipotential surfaces have the shape of lenses in tlie field between two cylinders biased at different voltages. The focusing properties of the electron optical lens are specified by focal points located at focal lengthsandy2, measured relative to the principal planes, The two principal rays emanating... Figure Bl.6.1 Equipotential surfaces have the shape of lenses in tlie field between two cylinders biased at different voltages. The focusing properties of the electron optical lens are specified by focal points located at focal lengthsandy2, measured relative to the principal planes, The two principal rays emanating...
Lattice models have been studied in mean field approximation, by transfer matrix methods and Monte Carlo simulations. Much interest has focused on the occurrence of a microemulsion. Its location in the phase diagram between the oil-rich and the water-rich phases, its structure and its wetting properties have been explored [76]. Lattice models reproduce the reduction of the surface tension upon adsorption of the amphiphiles and the progression of phase equilibria upon increasmg the amphiphile concentration. Spatially periodic (lamellar) phases are also describable by lattice models. Flowever, the structure of the lattice can interfere with the properties of the periodic structures. [Pg.2380]

An alternative method that can be used to characterize the topology of PES is the line integral technique developed by Baer [53,54], which uses properties of the non-adiabatic coupling between states to identify and locate different types of intersections. The method has been applied to study the complex PES topologies in a number of small molecules such as H3 [55,56] and C2H [57]. [Pg.254]

The location of the crossing seam (or seam) for an X3 system is established from the requirement that /-ab = rec = r c, where j-ab, rec, and fAc are the interatomic distances. Since the goal are the the geometric properties produced by this seam, hyperspherical coordinates (p,0,atomic masses are equal, say iiiB = me, the seam is defined [5] by... [Pg.608]

Approximation Property We assume that the classical wavefunction 4> is an approximate 5-function, i.e., for all times t G [0, T] the probability density 4> t) = 4> q,t) is concentrated near a location q t) with width, i.e., position uncertainty, 6 t). Then, the quality of the TDSCF approximation can be characterized as follows ... [Pg.382]

With all-atom simulations the locations of the hydrogen atoms are known and so the order parameters can be calculated directly. Another structural property of interest is the ratio of trans conformations to gauche conformations for the CH2—CH2 bonds in the hydrocarbon tail. The trans gauche ratio can be estimated using a variety of experimental techniques such as Raman, infrared and NMR spectroscopy. [Pg.413]

Location of the compound within a class (or homologous series) of compounds. Reference to the literature or to tables of the physical properties of the class (or classes) of organic compounds to which the substance has been assigned, will generally locate a number of compounds which boil or melt within 6° of the value observed for the unknown. If other physical properties e.g., refractive index and density for a hquid) are available, these will assist in deciding whether the unknown is identical with one of the known compounds. In general, however, it is more convenient in practice to prepare one, but preferably two, crystalhne derivatives of the substance. [Pg.1027]

The electron configuration is the orbital description of the locations of the electrons in an unexcited atom. Using principles of physics, chemists can predict how atoms will react based upon the electron configuration. They can predict properties such as stability, boiling point, and conductivity. Typically, only the outermost electron shells matter in chemistry, so we truncate the inner electron shell notation by replacing the long-hand orbital description with the symbol for a noble gas in brackets. This method of notation vastly simplifies the description for large molecules. [Pg.220]

Group additivity methods must be derived as a consistent set. It is not correct to combine fragments from different group additivity techniques, even for the same property. This additivity approximation essentially ignores effects due to the location of one functional group relative to another. Some of these methods have a series of corrections for various classes of compounds to correct for this. Other methods use some sort of topological description. [Pg.108]

The success of simple theoretical models in determining the properties of stable molecules may not carry over into reaction pathways. Therefore, ab initio calculations with larger basis sets may be more successful in locating transition structures than semi-empir-ical methods, or even methods using minimal or small basis sets. [Pg.307]

Interpreting Control Charts The purpose of a control chart is to determine if a system is in statistical control. This determination is made by examining the location of individual points in relation to the warning limits and the control limits, and the distribution of the points around the central line. If we assume that the data are normally distributed, then the probability of finding a point at any distance from the mean value can be determined from the normal distribution curve. The upper and lower control limits for a property control chart, for example, are set to +3S, which, if S is a good approximation for O, includes 99.74% of the data. The probability that a point will fall outside the UCL or LCL, therefore, is only 0.26%. The... [Pg.718]

In discussing Fig. 4.1 we noted that the apparent location of Tg is dependent on the time allowed for the specific volume measurements. Volume contractions occur for a long time below Tg The lower the temperature, the longer it takes to reach an equilibrium volume. It is the equilibrium volume which should be used in the representation summarized by Fig. 4.15. In actual practice, what is often done is to allow a convenient and standardized time between changing the temperature and reading the volume. Instead of directly tackling the rate of collapse of free volume, we shall approach this subject empirically, using a property which we have previously described in terms of free volume, namely, viscosity. [Pg.251]

It has been hypothesized that cross-linked polymers would have better mechanical properties if interchain bridges were located at the ends rather than the center of chains. To test this, low molecular weight polyesters were synthesizedf... [Pg.302]


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See also in sourсe #XX -- [ Pg.294 ]




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