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Particular features

The following comments can be made about the results found for the parameters introduced in the model. [Pg.109]

The halides of Rubidium and Cesium ions could be described by taking the crystallographic diameter and imposing = Ofor these ions. [Pg.109]

The first relation is interpreted by a decrease in hydration as concentration is increased. The second relation is consistent with theoretical and experimental studies of the dielectric properties of solutions. [Pg.110]

For associating electrolytes the values adjusted for K are of the same order of magnitude as the literature values, when available. [Pg.110]

A nice feature of eqs 5.42 and 5.43 is that no new adjustable parameter is required for mixed electrolytes with a common cation. The parameters of the pure electrolytes will normally suffice  [Pg.110]


In world practice RCT application is considered to the decision of control of the high density objects. The particular feature of RCT is the possibility of the reception of the quantitative information. Besides, the absence of characteristic to X-ray CT result distortions, which are caused by variation of an average value of polychromatic radiation energy, when it passes through an article, promotes the increase of accuracy characteristics of radionuclide CT... [Pg.598]

The algorithm of calculating crack depth is realized in electropotential device Zond IGT-97 for measuring cracks depth. Its structure diagram is shown in Fig. 8 Using quasi-direct current is the device particular feature that made it possible to reduce its dimensions and weight. [Pg.649]

The measurement of the current for a redox process as a fiinction of an applied potential yields a voltaimnogram characteristic of the analyte of interest. The particular features, such as peak potentials, halfwave potentials, relative peak/wave height of a voltaimnogram give qualitative infonnation about the analyte electrochemistry within the sample being studied, whilst quantitative data can also be detennined. There is a wealth of voltaimnetric teclmiques, which are linked to the fonn of potential program and mode of current measurement adopted. Potential-step and potential-sweep... [Pg.1926]

Generally speaking the three models offer complementary information Organic chemists use all three emphasizing whichever one best suits a particular feature of struc ture or reactivity Until recently the Lewis and orbital hybridization models were used far more than the molecular orbital model But that is changing... [Pg.93]

Atmospheric corrosion is electrochemical ia nature and depends on the flow of current between anodic and cathodic areas. The resulting attack is generally localized to particular features of the metallurgical stmcture. Features that contribute to differences ia potential iaclude the iatermetaUic particles and the electrode potentials of the matrix. The electrode potentials of some soHd solutions and iatermetaUic particles are shown ia Table 26. Iron and sUicon impurities ia commercially pure aluminum form iatermetaUic coastitueat particles that are cathodic to alumiaum. Because the oxide film over these coastitueats may be weak, they can promote electrochemical attack of the surrounding aluminum matrix. The superior resistance to corrosion of high purity aluminum is attributed to the small number of these constituents. [Pg.125]

Since the polymer is far from completely stereoregular the level of crystallinity is fairly modest, with a typical value of 25%. The crystalline melting point is about 90°C and the is -23°C. Such materials are rheologically similar to LDPE. Bottles and films are transparent. The particular features of the polymer... [Pg.307]

Whereas the isotactic polymer has not been commercialised Dow were scheduled to bring on stream plant with a nameplate capacity of 37 000 t.p.a. in 1999 to produce a syndiotactic polystyrene under the trade name Questra. The particular features of this material are ... [Pg.454]

The particular features of the nylons should also be taken into account in extrusion. Dry granules must be used unless a devolatilising extruder is employed. Because of the sharp melting point it is found appropriate to use a screw with a very short compression zone. Polymers of the lowest melt viscosity are to be avoided since they are difficult to handle. Provision should be made to initiate cooling immediately the extrudate leaves the die. [Pg.501]

The manufacturers stress ease of processing as a particular feature of the material. Recommended melt temperatures are in the range 320-340°C and mould temperatures are 135-165°C. Mould shrinkage of glass-filled grades is usually of the order of 0.2-0.4% in the flow direction and up to twice this value in the transverse direction. The materials are notable for their ability to withstand vapour phase and infrared soldering processes. [Pg.516]

One particular feature of PPO is its exceptional dimensional stability amongst the so-called engineering plastics. It has a low coefficient of thermal expansion, low moulding shrinkage and low water absorption, thus enabling moulding to close tolerances. [Pg.589]

In 1975 Wacker-Chemie introduced silicones under the name of m-polymers. These are also room temperature curing liquid polymers which give rubbery materials on cross-linking and are available both as one- and two-component systems. Their particular feature is that they contain dispersions of copolymers such as those of styrene and n-butyl acrylate in the shape of rods or rice grains in the fluid silicone polymer. A small amount of the organic copolymer is also grafted onto the silicone backbone. [Pg.836]

Particular features of some commercial CFD codes—A comparison... [Pg.826]

Calendering can achieve surprising accuracy on the thickness of a sheet. Typically the tolerance is 0.005 mm but to achieve this it is essential to have very close control over roll temperatures, speeds and proximity. In addition, the dimensions of the rolls must be very precise. The production of the rolls is akin to the manufacture of an injection moulding tool in the sense that very high machining skills are required. The particular features of a calender roll are a uniform specified surface finish, minimal eccentricity and a special barrel profile ( crown ) to compensate for roll deflection under the very high presurres developed between the rolls. [Pg.315]

The current pulse described in Eq. (5.1) is markedly different from that describing the elastic-dielectric. Particular features of the solution may be characterized by solutions for current j, at times t = 0 and if at time t/Uy. They are... [Pg.100]

As mentioned above, the unit operation of crystallization rarely exists in isolation but is normally part of a wider particulate processing system as illustrated schematically, in a very simplified form, in Figure 9.2. A particular feature of such processes is the variety of unit operations and the range of equipment types that may be employed at any stage. [Pg.262]

One particular feature of ionic liquids lies in their solvation properties, not only for hydrophobic compounds but also for hydrophilic compounds such as carbohydrates. Park and Kazlauskas reported the regioselective acylation of glucose in 99 % yield and with 93 % selectivity in [MOEMIM][BF4] (MOE = CH3OCH2CH2), values much higher than those obtained in the organic solvents commonly used for this purpose (Entry 18) [22] (Scheme 8.3-4). [Pg.344]

All types will not be treated in detail, but consideration of their particular features is important in many situations. [Pg.161]

Heat pumps. Both the source and sink of heat pumps can be gas or liquid. The particular feature of the heat pump is that the source is at a lower temperature than the sink and is upgraded by the heat pump. To obtain a reasonable efficiency it is essential that heat is required at a low temperature and the source and sink are close in temperature. [Pg.267]

The H-type cell devised by Lingane and Laitinen and shown in Fig. 16.9 will be found satisfactory for many purposes a particular feature is the built-in reference electrode. Usually a saturated calomel electrode is employed, but if the presence of chloride ion is harmful a mercury(I) sulphate electrode (Hg/Hg2 S04 in potassium sulphate solution potential ca + 0.40 volts vs S.C.E.) may be used. It is usually designed to contain 10-50 mL of the sample solution in the left-hand compartment, but it can be constructed to accommodate a smaller volume down to 1 -2 mL. To avoid polarisation of the reference electrode the latter should be made of tubing at least 20 mm in diameter, but the dimensions of the solution compartment can be varied over wide limits. The compartments are separated by a cross-member filled with a 4 per cent agar-saturated potassium chloride gel, which is held in position by a medium-porosity sintered Pyrex glass disc (diameter at least 10 mm) placed as near the solution compartment as possible in order to facilitate de-aeration of the test solution. By clamping the cell so that the cross-member is vertical, the molten... [Pg.609]

In just the same way as differential pulse polarography represents a vast improvement over conventional polarography (see Section 16.10), the application of a pulsed procedure leads to the greatly improved technique of differential pulsed anodic (cathodic) stripping volammetry. A particular feature of this... [Pg.622]

The difference between the two types of case cannot, therefore, concern what was or was not known when theory was produced. Instead the crucial difference is the fact that, in the cases of little or no support, certain aspects of the theory concerned were fixed precisely to yield the phenomena at issue. The relative velocities around the deferent and epicyclic circles in Ptolemy s theory had to be read off the phenomena of stations and retrogressions in order for that theory to yield those phenomena. The details of the fossil-accommodating version of creationism had to be read off the already known fossil record—which particular pretty pictures God chose to draw and what particular features the bone-like structures have can only be determined by observation. [Pg.61]

The cause of the weaker G dependence must be ascribed to some particular feature of geometry, although exactly what it is has not been found. All of the three bundles involved had their rods supported and correctly positioned by wires wrapped helically around certain of the rods, and it is possible that the wires caused an unfavorable distribution of steam and water. However, it is doubtful that the wire wraps were themselves responsible, since several of the bundles conforming to Eq. (28) were also wire wrapped. (Other devices used for rod supports are suitably spaced grids and ferrules.) The explanation most probably lies in a combination of the effects of the wire wraps with the effects of given rod diameters and rod spacings. For ease of identification, the data that conform with Eq. (28) are hereafter called normal data. [Pg.262]

The phenyl substitution provides both the chromophore necessary for photoactivity and the stabilization of the initially formed radical. The reported photochemical extrusion of SO from 2,2,4,4-tetraacetylthietane263b to give the corresponding cyclopropane appears to be a unique case associated with the particular features of the irradiated molecule. [Pg.452]

The particular features of the problem, namely the properties of kernel (7.15) of the relaxational part of (7.13) and of Hamiltonian (7.12) in the dynamical part of (7.13), allow one to advance essentially in solving kinetic equation (7.13). [Pg.232]

It is now widely accepted that the compositions of the atmosphere and world ocean are dynamically controlled. The atmosphere and the ocean are nearly homogeneous with respect to most major chemical constituents. Each can be viewed as a reservoir for which processes add material, remove material, and alter the compositions of substances internally. The history of the relative rates of these processes determines the concentrations of substances within a reservoir and the rate at which concentrations change. Commonly, only a few processes predominate in determining the flux of a substance between reservoirs. In turn, particular features of a predominant process are often critical in controlling the flux of a phase through that process. These are rate-controlling steps. [Pg.195]

Systematic studies of the selectivity of electrophilic bromine addition to ethylenic bonds are almost inexistent whereas the selectivity of electrophilic bromination of aromatic compounds has been extensively investigated (ref. 1). This surprising difference arises probably from particular features of their reaction mechanisms. Aromatic substitution exhibits only regioselectivity, which is determined by the bromine attack itself, i.e. the selectivity- and rate-determining steps are identical. [Pg.100]

To understand the circumstances in which particular features of mass spectrometry, such as high-resolution measurements, MS-MS and cone-voltage fragmentation, selected-ion monitoring and selected-decomposition monitoring, may be nsed to address particular analytical problems. [Pg.186]

Chemists do not make things easy for the novice molecules of a substance can be represented in a variety of ways to illustrate particular features, and to the novice these can seem to be different stmctures. Hoffman (1995) and Hoffman and Las-zlo (1991) illustrate this point well through various representations of a molecule of camphor (Fig. 1.7). [Pg.24]

In a reactor at low pressure (0.2-0.3 MPa) and moderate temperature (375 °C) the PVC is chemically and thermally degraded. A particular feature of the process is that the chlorine in the PVC reacts in part with the fillers in PVC and is neutralised with the formation of CaCl2. In similar vein, metal stabilisers in PVC are converted into the respective metal chlorides (lead, cadmium, zinc and/or barium). At current PVC waste compositions these chlorides consist of 60% lead which can be purified and re-used. The reaction in the end results in the following solid, liquid and gaseous products. [Pg.16]


See other pages where Particular features is mentioned: [Pg.348]    [Pg.155]    [Pg.631]    [Pg.661]    [Pg.663]    [Pg.72]    [Pg.313]    [Pg.377]    [Pg.447]    [Pg.34]    [Pg.262]    [Pg.84]    [Pg.65]    [Pg.80]    [Pg.20]    [Pg.67]    [Pg.173]    [Pg.382]    [Pg.400]    [Pg.102]   


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