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Space radiation, defined

This equation defines so-called "Elwald Space". Radiation of appropriate wavelength, impinging upon ordered rows of atoms, produces cones of scattered radiation, as follows ... [Pg.376]

In order to do justice to the coagulation of a 3D tumor geometry, it must be possible to heat an approximately spherical volume of tissue at the same time. For this reason application systems of defined space radiation characteristics have been developed, the distal ends of which are prepared in such a way that the result is an even circumference of radiation. [Pg.350]

Outer space, often called vacuum in space, is defined as void that exists beyond any celestial body including the Earth. It is not completely void (perfect vacuum) but contains low density of particles, predominantly hydrogen plasma, as well as magnetic fields, electromagnetic radiation, and neutrinos. [Pg.829]

Radiative heat transfer is perhaps the most difficult of the heat transfer mechanisms to understand because so many factors influence this heat transfer mode. Radiative heat transfer does not require a medium through which the heat is transferred, unlike both conduction and convection. The most apparent example of radiative heat transfer is the solar energy we receive from the Sun. The sunlight comes to Earth across 150,000,000 km (93,000,000 miles) through the vacuum of space. FIcat transfer by radiation is also not a linear function of temperature, as are both conduction and convection. Radiative energy emission is proportional to the fourth power of the absolute temperature of a body, and radiative heat transfer occurs in proportion to the difference between the fourth power of the absolute temperatures of the two surfaces. In equation form, q/A is defined as ... [Pg.613]

The difficulty in setting up the initial system for color comparisons cannot be underestimated. The problem was enormous. Questions as to the suitability of various lamp sources, the nature of the filters to be used, and the exact nature of the primary colors to be defined occupied many years before the first attempts to specify color in terms of the standard observer were started. As we said previously, the Sun is a black-body radiator having a spectral temperature of about 10,000 °K (as viewed directly from space). Scattering and reflection... [Pg.422]

Both types of insulation act to suppress thermal radiation by the intermediate shield principle. The insulation also acts to reduce the effective cell size for any residual gas in the vacuum space, thereby suppressing the thermal conductivity of the gas. In a typical commercial superinsulated dewar, there are about 50 layers of superinsulation, corresponding to a thickness of about one inch. The first few layers are the most effective in the attenuation of thermal radiation however the subsequent layers are important for the suppression of thermal conductivity of any residual gas. One can define an effective thermal conductivity for these insulations, which in the case of superinsulation is about 10 6 W/(cmK) between 300 and 4K. [Pg.125]

As mentioned above, the formalism of the reciprocal lattice is convenient for constructing the directions of diffraction by a crystal. In Figure 3.4 the Ewald sphere was introduced. The radius of the Ewald sphere, also called the sphere of reflection, is reciprocal to the wavelength of X-ray radiation—that is, IX. The reciprocal lattice rotates exactly as the crystal. The direction of the beam diffracted from the crystal is parallel to MP in Figure 3.7 and corresponds to the orientation of the reciprocal lattice. The reciprocal space vector S(h k I) = OP(M/) is perpendicular to the reflecting plane hkl, as defined for the vector S. This leads to the fulfillment of Bragg s law as S(hkI) = 2(sin ())/X = 1 Id. [Pg.78]

Quantum theory considers radiation as a stream of energy packets - photons or quanta - travelling through space at a constant velocity (c when in a vacuum). The energy of a photon is related to the frequency of the radiation, as defined in wave theory, by the expression... [Pg.271]

Solar energy is defined as the radiant energy transmitted by the Sun and intercepted by Earth. It is transmitted through space to Earth by electromagnetic radiation with wavelengths ranging between 0.20 and 15 pm. The availability of solar fiux for terrestrial applications varies with season, time of day, location, and collecting surface orientation. In this section, we shall treat these matters analytically (Kutz, 2007). [Pg.30]

A simple thought experiment due to Einstein gives a basic idea of the interaction of electromagnetic radiation with matter. Consider a space surrounded on all sides by perfectly reflecting mirrors (Figure 2.9). Inside this cavity there is a hot material body which is in thermal equilibrium with the radiation which fills the cavity. This radiation is then isotropic, as it fills, in a random manner, all the space of the cavity its intensity can be defined as an energy per unit volume. [Pg.22]

REFRACTIVE INDEX. The phase velocity of radiation in tree space divided by the phase velocity of the same radiation in a specified medium. Because of the Snell law (see also Refraction) the refractive index may also be defined as the ratio of the sine of the angle of incidence to tile sine of the angle of refraction. [Pg.1426]

It can be shown that the Sagnac effect with platform at rest is the rotation of the plane of linearly polarized light as a result of radiation propagating around a circle in free space. Such an effect cannot exist in the received view where the phase factor in such a round trip is always the same and given by Eq. (554). However, it can be shown as follows that there develops a rotation in the plane of polarization when the phase is defined by Eq. (553). It is now known that the phase must always be defined by Eq. (553). Therefore, proceeding on this inference, we construct plane polarized light as the sum of left and right circularly polarized components ... [Pg.93]

Following Fraser et al. (4), we choose to represent the scattered intensity in terms of a cylindrically symmetric "specimen intensity transform" I (D), where D is a position vector in reciprocal space. Figure 10 shows the Ewald sphere construction, the wavelength of the radiation being represented by X. The angles p and X define the direction of the diffracted beam and are related to the reciprocal-space coordinates (R, Z) and the pattern coordinates (u,v) as follows ... [Pg.130]


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