Basic property

The basic properties of paper include the dimensions and the mass. In the case of sheet material such as paper, the basis weight niA is determined in accordance with 

Copyright 2006 WILEY-VCH Verlag GmbH Co. KGaA, Weinheim ISBN 3-527-30997-7 

Another basic property of paper is the caliper. As paper is compressible the caliper must be defined in terms of the measuring instrament ISO 534 (2003) specifies an instrument with two parallel planar measuring surfaces of 200 mm which act on the sample with a surface pressure of 100 kPa. The resulting distance between the surfaces is the caliper D of the paper. 

The ratio of the basis weight to the caliper is the density of the paper. The reciprocal density is the specific volume. 

We now discuss the basic properties of spectrometers, relevant for laser spectroscopy. For a more detailed treatment see for instance [4.1-4]. 

The selection of the optimum type of spectrometer for a particular experiment is guided by some basic characteristics of spectrometers and their relevance for the particular application. The basic properties which are important not only for spectrographs but for all dispersive optical instruments may be listed as follows  

1) The light-gathering power or Hendue often called the speed of the 

2) The spectral transmittance T(A) of the instrument, which is limited by the transparency of the lenses and prism in the prism spectrograph or by the reflectivity R(a) of the mirrors and grating in grating spectrographs. 

3) The spectral resolving power a/aa which specifies the minimum separation AA of two spectral lines that can just be resolved. 

Amorphous Te02 and tellurite glasses exhibit a range of excellent properties, which give them great potential in a wide range 

The optical properties of tellurites can also be modified at will with the addition of different elements [4], For instance, Na, Li, K, or Rb can be added to lower the refractive index from 2.1 down to 1.7. Addition of F- or I-based dopants can extend the mid-IR transmission. Ba and Li can improve the UV transmission. The third-order nonlinearity can also be increased around two to three times by adding W, Nb, Tl, etc. [13-15] or reduced by up to 0.3 by adding Al, Li, Na, etc. [2,14,16]. This degree of tailorability provides a great deal of flexibility for fiber and integrated device fabrication. 

Because of the high technological potential of tellurite glasses, their basic structures have been studied by X-ray [5,6,17], electron energy loss spectroscopy [18], neutron diffraction [8, 17, 19, 20], nuclear magnetic resonance [NMR] [17, 21-27], Raman studies [2, 22-24, 26-29], and ab initio cluster calculation [8, 23, 28-35]. 

Brady [5, 6] first undertook a detailed study of the structure of Te02-based glass by electron radial distribution function [RDF] methods using X-ray diffraction [XRD] analysis. Brady found that there were two well-resolved primary peaks, one at about 1.95 A and the other at about 2.75 A, and two other well-resolved secondary peaks, at 3.63 A and 4.38 A. The first two peaks correspond to the two sets of equatorial and axial Te-0 bonds. The latter two peaks overlap, and their extracted distances correspond to the two preferred sets of Te-Te distances. 

Azo BCs are multifunctional polymeric materials, which combine the photochemical properties of azo polymers and the microphase separation of functional BCs. On the one hand, the azo block and the other segments cannot be miscible, unlike statistically random copolymers in which the azo moieties are dispersed homogeneously over the whole bulk films. On the other hand, the azo BCs cannot form macroscopically phase-separated structures like polymer blends (Bates and Fredrichson, 1999). 

The azo moiety may play the roles of both mesogen and photosensitive chromophore, when it is attached to the polymer main chain by a longer soft spacer. Both the photoisomerization and the phase transition of the LC to the isotropic phase are involved in the process of microphase separation because of 

On the one hand, the azo BCs inherit most of the excellent properties of azo homopolymers (Ichimura, 2000), such as trans is photoisomerization, photo-selective alignment with azo transition moments almost perpendicular to the polarization direction of the actinic light, and photochemical phase transition, since the trans-azo can be a mesogen because its molecular shape is rodlike, whereas the cis-azio never shows any LC phase because of its bent shape. All the illustrations of the photosensitive performances are shown in Fig. 12.3 (Yu et al., 2005a). 

NiAl is the best known example of the intermetallics with a cubic B2 structure (Fig. 1), which form one of the largest groups of intermetallics (Baker and Mun-roe, 1990). The physical and mechanical properties of NiAl have recently been reviewed in detail (Miracle, 1993). As is illustrated by the phase diagram in Fig. 20, 

The density of NiAl is low at 5.9 g/cm for the stoichiometric composition compared with conventional Ni-base alloys, and it increases with decreasing A1 content (Rusovic and Warlimont, 1977 Har-mouche and Wolfenden, 1987). It is noted that the density change per unit of A1 content is larger for Al-rich NiAl than for Ni-rich Ni Al because of the difference in the defect structure. 

The elastic behavior of NiAl has been studied repeatedly and the elastic moduli have been determined experimentally for polycrystals and single crystals as a function of composition and temperature (Wasilewski, 1966 Rusovic and Warlimont, 1977, 1979 Harmouche and Wolfenden, 1985, 1987). The elastic behavior has also been studied theoretically by quantum-mechanical, ab initio calculations, and the resulting elastic moduli are in close agreement with the experimental values (Yoo et al. 1990 Fu and Yoo, 1992b Freeman etal., 1992 Yoo and Fu, 1993). 

The Young s modulus of polycrystalline NiAl with a stoichiometric composition is about 235 GPa at room temperature (Harmouche and Wolfenden, 1987). The elastic moduli are functions of the composition, and the Young s modulus reaches a maximum of slightly more than 235 GPa, not at the stoichiometric composition as is expected, but at about 48 at.% Al which may be related to the difference in the defect character on both sides of stoichiometry. The effect of excess vacancies, which are produced by quenching from high temperatures, on the elastic behavior was studied 

1992 Bakker et al., 1992). Only recently a model, which is based on a combination of two mechanisms, has been proposed for describing the composition dependence of diffusion in B2 phases (Kao and Chang, 1993). It should be noted that the understanding of the basic diffusion processes for other intermetallics is still less than for NiAl and other B2 phases (Wever, 1992). Diffusion studies of multi-component systems are rare, and with respect to NiAl base alloys only data for the ternary phase (Ni,Fe)Al are available from a systematic study of the system Ni-Al-Fe (Cheng and Dayananda, 1979 Dayananda, 1992). Recently, the effect of Cr on diffusion in NiAl has been studied (Hopfe et al., 1993). 

When the spectral intensity within the solid angle dQ = 1 sr is incident on the entrance slit of area A, a spectrometer with an acceptance angle Q transmits the radiant flux within the spectral interval dX 

The product U = Af2 h often named etendue. For the prism spectrograph the maximum solid angle of acceptance, Q = F/ ff, is limited by the effec- 

Often the wavelength of lasers is measured with a spectrometer. In this case, it is not recommended to direct the laser beam directly onto the entrance slit, because the prism or grating would be not uniformely illuminated. This decreases the spectral resolution. Furthermore, the symmetry of the optical path with respect to the spectrometer axis is not guaranteed with such 

When a light beam with spectral intensity / (A), cross section and spectral radiation power 

For prism spectrometers, the spectral transmission depends on the material of the prism and the lenses. Using fused quartz, the accessible spectral range spans from about 180 to 3000 nm. Below 180nm (vacuum-ultraviolet region), the whole spectrograph must be evacuated, and lithium fluoride or calcium fluoride must be used for the prism and the lenses, although most VUV spectrometers are equipped with reflection gratings and mirrors. 

Many vibrational-rotational transitions of molecules such as H2O or CO2 fall within the range 3-10 p.m, causing selective absorption of the transmitted radiation. Infrared spectrometers therefore have to be either evacuated or filled with dry nitrogen. Because dispersion and absorption are closely related (see Sect. 2.6), prism materials with low absorption losses also show low dispersion, resulting in a limited spectral resolving power (see below). 

Often the wavelength of lasers is measured with a spectrometer. In this case, it is not recommended to direct the laser beam directly onto the en- 

The passage of electrons or other particles with charge q and mass m through an electrostatic lens system is governed by their motion under the action of the electric field. In the case considered here, cylindrical symmetry around the optical axis (z-axis) and paraxial rays will be assumed. Of the cylindrical coordinates only the transverse radial coordinate p and the distance coordinate z are of relevance, and the electrostatic potential of the lens is given by q (p, z). As shown in Section 10.3.1, in the paraxial approximation the potential q (p, z) is fully determined by the potential S(z) = p(p = 0, z) at the symmetry axis. Hence, the equations of motion and the fundamental differential equation of an electrostatic lens depend only on this potential. The fundamental lens equation is given by (see equ. (10.38)) 

This establishes a connection between the coordinate p and the potential D(z) with its derivatives in z (for the meaning of the tilde on the potential 4 (z), which differs from S(z), see below). Several important factors can be deduced from this differential equation  

In order to derive the full properties of a lens system, the fundamental lens equation has to be solved for individual rays subject to the influence of the given potential d (z). However, without going into the details for such a procedure, some aspects, which are important for axial-symmetrical electrostatic lenses with paraxial rays, can be listed by using results from light optics  

If this equation is compared with the result from light optics where glass bodies are used, one notices that the square-root of the potentials D and G r takes over the role of the refraction indices ne and nr. The relation states that there are different focal lengths in an immersion lens in which the asymptotic potentials , and 5 r or, correspondingly, the kinetic energies of the electrons 

Using the similarity of the triangles shown in Fig. 4.31 (shaded vertically and horizontally), one obtains for the linear magnification the equivalent expression 

Poincare theorem. Given n random events A ,.. ., An, the probability of their union is given by 

Conditional probability. Given the random events A and B, the conditional probability of A for observed B is defined by 

The angular momentum of a massive particle about the origin is introduced as the vector normal to the plane of motion 

In a three-dimensional space (having i, j, k unit vectors) / can be written in the determinantal form 

The optical absorption or excitation lineshape of dopant molecules in crystalline matrices at low temperatures has been investigated both experimentally and theo- 

Tn denotes the dephasing time of the optical transition, T the lifetime of the excited state (fluorescence hfetime) and the pure dephasing time. At low temperatures T is essentially independent on temperature while shows a strong dependence on temperature. The actual value of at a given temperature depends on the excitation of low frequency modes (phonons, librations) that couple to the electronic transition of the chromophore. In crystalline matrices at low temperatures (T 2 K) Tl approaches infinity as host phonons and local modes are essentially quenched and the linewidth is solely determined by the lifetime contribution. 

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Spatial synnnetry is one of the basic properties of a surface or interface. If the syimnetry of the surface is known a priori, then this knowledge may be used to simplify the fomi of the surface nonlinear susceptibility as discussed in section Bl,5,2,2. Conversely, in the absence of knowledge of the surface synnnetry, we may characterize the fonn of -iexperimentally and then make inferences about the synnnetry of the surface... 

Pluta M 1988 Advanced Light Microscopy, voi 1 Principies and Basic Properties (Amsterdam Elsevier)... 

In order to rmderstand how light can be controlled, we must first review some of tire basic properties of tire electromagnetic field [8], The electromagnetic tlieory of light is governed by tire equations of James Clerk Maxwell. The field phenomena in free space with no sources are described by tire basic set of relationships below ... 

Basic properties of product Be(OH)2 amphoteric MgO insoluble slightly MjOH), soluble... 

This reaction is due to the very strong basic property of the hydride ion H" which behaves as a powerful proton acceptor and is therefore strongly basic, i.e. 

This can be extracted from impure phosphine prepared by the action of sodium hydroxide on phosphorus. Unlike hydrazine, it has no basic properties. It is a powerful reducing agent and burns spontaneously in air, this reaction explaining why impure phosphine containing traces of diphosphane ignites spontaneously in air. 

Precautions, (i) The above tests must be carried out with discretion. If the substance is only moderately soluble in the solvent selected, and a comparatively large volume of the latter is required, the consequent dilution of the acid in the reagent may cause the separation of the free 2,4 dinitrophenylhydrazine (although this is more likely to happen with Reagent B than with A). Furthermore, if the compound under investigation should have basic properties, the neutralisation of part of the acid in the reagent may have the same result. 

Physical Properties, (i) Aromatic. Colourless when freshly prepared, but usually brown. MonomethylaniUne, CgHjNHCH, b.p. 193°, and monoethylaniline, CgHjNHCjHj, b.p. 206 , diphenylamine,(C6H5)2NH, m.p. 54 , are all insoluble in water, the two alkylanilines having well-marked basic properties, diphenylamine being feebly basic and insoluble in dilute mineral acids. 

Physical Properties. Glycine is a colourless crystalline solid soluble in water. Owing to the almost equal opposing effects of the amino and the carboxylic groups. its aqueous solution is almost neutral (actually, slightly acidic to phenolphthalein) and glycine is therefore known as a neutral ampholyte. f It exhibits both acidic and basic properties. 

Physical Properties. Colourless crystalline solid, soluble in boiling water, very sparingly soluble in cold water crystallises 2H2O. The strongly acidic — SO3H group suppresses the normal basic properties of the — NHj group the acid therefore dissolves readily in alkalis, but not in dilute mineral acids. 

In 1877, Maly (45) discussing formula 34 applied to thiohydantoine found it unable to explain the basic properties of the compound. He preferred a structure in which the -CH2-CO- group would be bonded to only one nitrogen atom. Meyer (46) prepared a monophenyl thiohydantoin (m.p. 178°C) by condensing diloroacetanilide with thiourea and proposed 42 for its structure. 

Sometimes the strongly basic properties of Gngnard reagents can be turned to synthetic advantage A chemist needed samples of butane specifically labeled with deuterium the mass 2 isotope of hydrogen as shown... 

J. G. Pritchard, Poly(VinylAlcohol) Basic Properties and Uses, Polymer Monographs, Vol. 4, Gordon Breach, New York, 1970. 

Acrylamide, C H NO, is an interesting difiinctional monomer containing a reactive electron-deficient double bond and an amide group, and it undergoes reactions typical of those two functionalities. It exhibits both weak acidic and basic properties. The electron withdrawing carboxamide group activates the double bond, which consequendy reacts readily with nucleophilic reagents, eg, by addition. 

Although NF is an amine, it exhibits virtually no basic properties and is not protonated by the HSO F—SbF —SO superacid medium at 20°C (19). Commercial scmbbing systems for unwanted NF are available (20) and work on the principle of pyrolysis of the NF over reactive substrates at high temperatures. 

The properties of a botanical gum are determined by its source, the climate, season of harvest, and extraction and purification procedures. Table 6 illustrates one of the important basic properties of all gums, ie, the relationship between concentration and solution viscosity. The considerable viscosity variation observed among gums from different sources determines, in part, their uses. 

The piC values of polymethine dyes depend on terminal group basicity (64) thus the protonation abHity diminishes if the basic properties of the residues decrease, passing from benzimidazole, quinoline, benzothiazole, to indolenine. On the other hand, the piC of higher homologues increases with chain lengthening. The rate constant of protonation is sensitive to other features, for example, substituents and rings in the chain and steric hindrance for short-chain dyes. 

ALkylamines are corrosive to copper, copper-containing alloys (brass), aluminum, 2inc, 2inc alloy, and galvani2ed surfaces. Aqueous solutions of aLkylamines slowly etch glass as a consequence of the basic properties of the amines in water. Carbon or stainless steel vessels and piping have been used satisfactorily for handling aLkylamines and, as noted above, some aLkylamines can act as corrosion inhibitors in boiler appHcations. 

Liquid fuels for ground-based gas turbines are best defined today by ASTM Specification D2880. Table 4 Hsts the detailed requirements for five grades which cover the volatility range from naphtha to residual fuel. The grades differ primarily in basic properties related to volatility eg, distillation, flash point, and density of No. 1 GT and No. 2 GT fuels correspond to similar properties of kerosene and diesel fuel respectively. These properties are not limited for No. 0 GT fuel, which allows naphthas and wide-cut distillates. For heavier fuels. No. 3 GT and No. 4 GT, the properties that must be limited are viscosity and trace metals. 

Functional Coatings. Whereas there are many types of functional coatings, the basic properties or characteristics that give a device utility are its electrical, magnetic, and optical properties. The electrical properties can be defined by the ability of the material to conduct or hinder flow of electrons. This characteristic resistance is expressed by... 

The acid-base properties of isoxazole and methylisoxazoles were studied in proton donor solvents, basic solvents or DMSO by IR procedures and the weakly basic properties examined (78CR(Q(268)613). The basicity and conjugation properties of arylisoxazoles were also studied by UV and basicity measurements, and it was found that 3-substituted isoxazoles were always less basic than the 5-derivatives. Protonation increased the conjugation in these systems (78KGS327). 

QRA is fundamentally different from many other chemical engineering activities (e.g., chemistry, heat transfer, reaction kinetics) whose basic property data are theoretically deterministic. For example, the physical properties of a substance for a specific application can often be established experimentally. But some of the basic property data used to calculate risk estimates are probabilistic variables with no fixed values. Some of the key elements of risk, such as the statistically expected frequency of an accident and the statistically expected consequences of exposure to a toxic gas, must be determined using these probabilistic variables. QRA is an approach for estimating the risk of chemical operations using the probabilistic information. And it is a fundamentally different approach from those used in many other engineering activities because interpreting the results of a QRA requires an increased sensitivity to uncertainties that arise primarily from the probabilistic character of the data. 

The left-hand side of our equation says that fast fracture will occur when, in a material subjected to a stress a, a crack reaches some critical size a or, alternatively, when material containing cracks of size a is subjected to some critical stress cr. The right-hand side of our result depends on material properties only E is obviously a material constant, and G, the energy required to generate unit area of crack, again must depend only on the basic properties of our material. Thus, the important point about the equation is that the critical combination of stress and crack length at which fast fracture commences is a material constant. 

Although a number of studies have been made concerning the basic properties of the RF vacuum spark used for excitation, the discharge is typically erratic, producing a widely fluctuating signal for mass analysis. For this reason, the most widely used form of this instrumentation consists of a mass spectrometer of the... 

FINCH, c.A. (Ed.), Polyvinyl alcohol Properties and Applications, Wiley New York (1973) PRITCHARD, J.G., Poly(Vinyl alcohol) Basic Properties and Uses, Macdonald, London (1970) Properties and Applications of Polyvinyl Alcohol (SCI Monograph No. 30), Society of the Chemical Industry, London (1968)... 

Increase in Density (crystallinity) Decrease in Melt Index Basic Properties Unaffected by Density and MI... 

These hazards cannot be changed—they are basic properties of the materials and the conditions of usage. The inherently safer approach is to reduce the hazard by reducing the quantity of hazardous material or energy, or by completely eliminating the hazardous agent. 

Chapter 3 of Volume 1 discusses many of the basic properties of gas and methods presented for calculating them. Chapter 6 of Volume 1 contains a brief discussion of heat transfer and an equation to estimate the heat required to change the temperature of a liquid. This chapter discusses heat transfer theory in more detail. The concepts discussed in this chapter can be used to predict more accurately the required heat duty for oil treating, as well as to size heat exchangers for oil and water. 

As we shall see, very often it is not a lack of sophisticated training that results in accidents hut ignorance of the basic requirements of the job or the basic properties of the materials and equipment handled. 

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