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Electric introduced

In 1982 General Electric introduced Ultem, a polyetherimide with the following structure ... [Pg.525]

Since one of the products of mixing an acid with a base is water, this is an appropriate place to examine water s curious properties. Splitting water into its component parts by means of electricity introduces the subject of electrochemistry, including the chemical battery and chromium plating. The component parts are elements -the basic substances of which the world around us is composed, and the topic that is treated next. And finally, the elements can be further broken down into atoms - the building blocks of the universe ... [Pg.4]

Self-cleaning oven General Electric introduces the self-cleaning electric oven. [Pg.2067]

The harmony which this theory of the definite evolution and the equivalent definite action of electricity introduces into the associated theories of definite proportions and electro-chemical affinity, is very great. According to it, the equivalent weights of bodies are simply those quantities of them which contain equal quantities of electricity, or have naturally equal electric powers it being the ELECTRICITY which determines the equivalent number, because it determines the combining force. Or, if we adopt the atomic theory or phraseology, then the atoms of bodies which are equivalents to each other in their ordinary chemical action, have equal quantities of electricity naturally associated with them."... [Pg.155]

This technology has since been introduced to the fossil power generating industry. To-date, several major utilities including the Termessee Valley Authority, Baltimore Gas and Electric and American Electric Power, as well as many others, have employed this technology to assess the condition of power-generating boiler tubes. [Pg.1064]

The influence of an applied magnetic field, as introduced in section Bl.5.2.2. is quite different from that of an applied electric field. A magnetic field may perturb the interfacial nonlinear response (and that of the weak bulk tenns), but it does not lead to any dipole-allowed bulk nonlmear response. Thus, in the presence of magnetic fields and magnetization, SHG remains a probe that is highly specific to surfaces and interfaces. It... [Pg.1298]

Introducing the complex notation enables the impedance relationships to be presented as Argand diagrams in both Cartesian and polar co-ordinates (r,rp). The fomier leads to the Nyquist impedance spectrum, where the real impedance is plotted against the imaginary and the latter to the Bode spectrum, where both the modulus of impedance, r, and the phase angle are plotted as a fiinction of the frequency. In AC impedance tire cell is essentially replaced by a suitable model system in which the properties of the interface and the electrolyte are represented by appropriate electrical analogues and the impedance of the cell is then measured over a wide... [Pg.1944]

For temperatures up to 100°, a water bath or steam bath is generally employed. The simplest form is a beaker or an enamelled iron vessel mounted on a suitable stand water is placed in the vessel, which is heated by means of a flame. This arrangement may be used for non-inflammable liquids or for refluxing liquids of low boiling point. Since numerous liquids of low boiling point are highly inflammable, the presence of a naked flame will introduce considerable risk of fire. For such liquids a steam bath or an electrically-heated water bath, provided with a constant-level device, must be used. If the laboratory is equipped with a... [Pg.57]

Fig. II, 37, 2 depicts the apparatus for dealing with comparatively small volumes of liquid. The essential feature is the special condenser with a take-off tube. A few small pieces of porous porcelain are introduced and the flask is heated either on a water bath or upon an electric hot plate. The assembly is also useful in the recrystaUisation of compounds which dissolve slowly excess of solvent may be employed, and the excess of solvent subsequently removed by distillation. Fig. II, 37, 2 depicts the apparatus for dealing with comparatively small volumes of liquid. The essential feature is the special condenser with a take-off tube. A few small pieces of porous porcelain are introduced and the flask is heated either on a water bath or upon an electric hot plate. The assembly is also useful in the recrystaUisation of compounds which dissolve slowly excess of solvent may be employed, and the excess of solvent subsequently removed by distillation.
Phenylacetylene. Support a 5-litre glass Dewar flask in a wooden case. Equip the flask with a lid of clear Perspex, provided with suitable apertures for a mechanical stirrer, introducing solids (e.g., sodium) or hquids, a calibrated dip stick for measuring the volume of liquid in the Dewar vessel, a gas mlet tube and an ammonia inlet arrange for an electric light to shine downwards into the flask. [Pg.900]

When the states P1 and P2 are described as linear combinations of CSFs as introduced earlier ( Fi = Zk CiKK), these matrix elements can be expressed in terms of CSF-based matrix elements < K I eri IOl >. The fact that the electric dipole operator is a one-electron operator, in combination with the SC rules, guarantees that only states for which the dominant determinants differ by at most a single spin-orbital (i.e., those which are "singly excited") can be connected via electric dipole transitions through first order (i.e., in a one-photon transition to which the < Fi Ii eri F2 > matrix elements pertain). It is for this reason that light with energy adequate to ionize or excite deep core electrons in atoms or molecules usually causes such ionization or excitation rather than double ionization or excitation of valence-level electrons the latter are two-electron events. [Pg.288]

The focus of this section is the emission of ultraviolet and visible radiation following thermal or electrical excitation of atoms. Atomic emission spectroscopy has a long history. Qualitative applications based on the color of flames were used in the smelting of ores as early as 1550 and were more fully developed around 1830 with the observation of atomic spectra generated by flame emission and spark emission.Quantitative applications based on the atomic emission from electrical sparks were developed by Norman Lockyer (1836-1920) in the early 1870s, and quantitative applications based on flame emission were pioneered by IT. G. Lunde-gardh in 1930. Atomic emission based on emission from a plasma was introduced in 1964. [Pg.434]

Fundamentally, introduction of a gaseous sample is the easiest option for ICP/MS because all of the sample can be passed efficiently along the inlet tube and into the center of the flame. Unfortunately, gases are mainly confined to low-molecular-mass compounds, and many of the samples that need to be examined cannot be vaporized easily. Nevertheless, there are some key analyses that are carried out in this fashion the major one i.s the generation of volatile hydrides. Other methods for volatiles are discussed below. An important method of analysis uses lasers to vaporize nonvolatile samples such as bone or ceramics. With a laser, ablated (vaporized) sample material is swept into the plasma flame before it can condense out again. Similarly, electrically heated filaments or ovens are also used to volatilize solids, the vapor of which is then swept by argon makeup gas into the plasma torch. However, for convenience, the methods of introducing solid samples are discussed fully in Part C (Chapter 17). [Pg.98]

All methods of plasma production require some electrons to be present as electric-discharge initiators. For a plasma torch, the initiating electrons are introduced from a piezoelectric spark directed into argon gas flowing in the interval between two concentric quartz tubes. [Pg.395]

As our discussion of scattering proceeds, we shall examine the coupling between the oscillating electrical field of light and the electrons of the scatterer in detail. First, it is useful to consider the interaction of an electric field with matter, as this manifests itself in the dielectric behavior of a substance. This will not only introduce us to the field-matter interaction, but will also provide some relationships which will be useful later. [Pg.666]

Fig. 38. Diagram comparing the optical characteristics of a standard binary chrome mask with a phase-shift mask. The changes in the electric fields introduced by the phase-shift elements result in a sharper light intensity profile at the wafer surface. Fig. 38. Diagram comparing the optical characteristics of a standard binary chrome mask with a phase-shift mask. The changes in the electric fields introduced by the phase-shift elements result in a sharper light intensity profile at the wafer surface.

See other pages where Electric introduced is mentioned: [Pg.116]    [Pg.333]    [Pg.221]    [Pg.149]    [Pg.116]    [Pg.333]    [Pg.221]    [Pg.149]    [Pg.257]    [Pg.150]    [Pg.217]    [Pg.329]    [Pg.180]    [Pg.586]    [Pg.1069]    [Pg.1266]    [Pg.1913]    [Pg.2760]    [Pg.167]    [Pg.429]    [Pg.365]    [Pg.199]    [Pg.55]    [Pg.321]    [Pg.358]    [Pg.485]    [Pg.604]    [Pg.880]    [Pg.283]    [Pg.1120]    [Pg.39]    [Pg.89]    [Pg.205]    [Pg.364]    [Pg.342]    [Pg.190]    [Pg.584]   
See also in sourсe #XX -- [ Pg.78 ]




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Introduced

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