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Sector spherical

The hemispherical analyser shown in Figure 8.5(d) works on a similar principle buf has fhe advanfage of collecting more phofoelecfrons. An analyser consisting of two concentric plates which are parts of hemispheres, so-called spherical sector plates, is often used in a spectiomefer which operafes for bofh UPS and XPS. [Pg.294]

V (spherical sector) = %7tRph, = 2 (open spherical sector), i = 1 (spherical cone)... [Pg.7]

Fig. A.I. Real spherical harmonics. The first one, Y , is a constant. The coordinate system attached to the unit sphere is shown. The two zonal harmonics, IT and II, section the unit sphere into vertical zones. The unshaded area indicates a positive value for the harmonics, and the shaded area indicates a negative value. The four sectoral harmonics are sectioned horizontally. The two tesserai harmonics have both vertical and horizontal nodal lines on the unit sphere. The corresponding "chemists notations," such as (3z — r ), are also marked. Fig. A.I. Real spherical harmonics. The first one, Y , is a constant. The coordinate system attached to the unit sphere is shown. The two zonal harmonics, IT and II, section the unit sphere into vertical zones. The unshaded area indicates a positive value for the harmonics, and the shaded area indicates a negative value. The four sectoral harmonics are sectioned horizontally. The two tesserai harmonics have both vertical and horizontal nodal lines on the unit sphere. The corresponding "chemists notations," such as (3z — r ), are also marked.
The data on kp and kt as reported in the literature differ considerably. Therefore, we conducted new studies on methyl methacrylate (MMA), benzyl methacrylate (BMA), and styrene (St) as monomers. The constants were obtained by applying the method of intermittent illumination (rotating sector) combined with stationary state methods. The viscosity of the solvents varied between 0.5 and 100 cP. No mixed solvents composed of low- and high-molecular components were used but pure solvents only, the molecules of which did not deviate very much from a spherical form (methyl formate, diethyl phthalate, diethyl malonate, dimethyl glycol phthalate, etc.). [Pg.14]

Figure 4.11 Definition of the solid angle fi0 of a point source Q accepted by the entrance slit S of a sector CMA. Two cross-cuts are shown (a) for a plane containing the symmetry axis of the analyser, (b) for a plane perpendicular to this axis. The principal ray starting at Q is shown together with the angular spreads from the finite acceptances in A and Acp. If expressed in spherical coordinates, the slit S has a width b = r2 A and a length i = i ,2 + A

Figure 4.11 Definition of the solid angle fi0 of a point source Q accepted by the entrance slit S of a sector CMA. Two cross-cuts are shown (a) for a plane containing the symmetry axis of the analyser, (b) for a plane perpendicular to this axis. The principal ray starting at Q is shown together with the angular spreads from the finite acceptances in A and Acp. If expressed in spherical coordinates, the slit S has a width b = r2 A and a length i = i ,2 + A<p = r sin 0 2 A<p as indicated. Their product M is the area of a sphere with radius r. If divided by r2, one obtains the solid angle fi0=sin 0 2 A 2 A<p. ...
Theoretical. The theory of steady state diffusion in a hollow sphere has been described by Crank (16). Because each frustum-shaped cell in the system closely approximates a spherical sector of a hollow sphere, a theoretical model can be developed on this basis to predict the release characteristics for this sytem. This assumption should be valid until the point is reached such that the curved interface (r in Figure 2) touches the flat impermeable backing, which should represent ca. 90% of the release. [Pg.328]

Fig. 14. Schematic diagram for XPS measurements with a spherical sector analyzer and electrostatic lenses. Fig. 14. Schematic diagram for XPS measurements with a spherical sector analyzer and electrostatic lenses.
Fig. 18 Spherical sector of 12 ring organoiridium lithium ion used in spherical name... Fig. 18 Spherical sector of 12 ring organoiridium lithium ion used in spherical name...
Fig. 23 Spherical sector of calix-3-arene used to form spherical name respectively. Fig. 23 Spherical sector of calix-3-arene used to form spherical name respectively.
Note that one did not have to draw the spherical sector for calix-4-arene as it is identical to the module illustrated in Figure 24. The only difference in the spherical name is the subscript denoting how many of these modules are combined to form the molecule. See spherical names (52) and (54). Upon comparing Cartesian names (51) and (53), on the other hand, one sees a familial, but not exact, duplicativity. [Pg.235]

Energy analysis of the photoelectrons is carried out by a spectrometer of which there are two types cylindrical and spherical sector. In both cases, they are in the form of a capacitor that focuses electrons with the same selected energy level to a detection point, spectrum acquisition is carried out sequentially by scanning the selected energy. [Pg.102]

Further extensions can be made when additional confinements are introduced. Following the example of [10], in which confinement in circular sectors was investigated, the dihedral confinement may be complemented with additional spherical and/or conical, one or two paraboloidal, and spheroidal and/or hyperboloidal boundaries. [Pg.117]

The numerical procedure used in association with the p, ax coordinates is as follows (12). The internal configuration space is divided into a number of spherical hyperradial sectors. The two-dimensional LHSFs are then determined at the center p of each sector and used to obtain the coupling matrix V7111 (p p) over the entire sector. Equation (178) is transformed into the firstorder nonlinear Bessel-Ricatti matrix differential equation... [Pg.452]

Figure 30. Cross-sectional view of the molecular-beam VUV photoionization apparatus. (1) Nozzle (2) skimmer (3) reaction gas cell (4) vertical quadrupole mass spectrometer (QMS) (5) steradiancy electron energy analyzer (6) spherical sector electron energy analyzer (7) channeltron electron detector (8) horizontal QMS. Taken from ref. 113. Figure 30. Cross-sectional view of the molecular-beam VUV photoionization apparatus. (1) Nozzle (2) skimmer (3) reaction gas cell (4) vertical quadrupole mass spectrometer (QMS) (5) steradiancy electron energy analyzer (6) spherical sector electron energy analyzer (7) channeltron electron detector (8) horizontal QMS. Taken from ref. 113.
Figure 17. A lowered-symmetry sector rule for the lactam chromophore n-7c long-wavelength transition. The curved surface is a spherical distortion of the YZ surface of octant rule nodal planes. Other nodal surfaces remain planar. The signs refer to the back octants. (From Ong et a/., 1977. Reproduced with permission of the American Institute of Physics.)... Figure 17. A lowered-symmetry sector rule for the lactam chromophore n-7c long-wavelength transition. The curved surface is a spherical distortion of the YZ surface of octant rule nodal planes. Other nodal surfaces remain planar. The signs refer to the back octants. (From Ong et a/., 1977. Reproduced with permission of the American Institute of Physics.)...
In the nanotechnology field, carbon-based materials and associated composites have received special attention both for fundamental and applicative research. In the first kind, carbon compounds may be included, often taking the form of a hollow spheres, ellipsoids, or mbes. Spherical and ellipsoidal carbon nanomaterials are referred to as fullerenes, while cylindrical ones are called nanombes and nanofibers. In the second class, one includes composite materials that combine carbon nanoparticles with other nanoparticles, or nanoparticles with large bulk-type materials. The unique properties of these various types of nanomaterials provide novel electrical, catalytic, magnetic, mechanical, thermal, and other features that are desirable for applications in commercial, medical, military, and enviromnental sectors. This is the case for conducting polymers (CPs) and carbon nanombes (CNTs) [1-5]. [Pg.209]

Fig. I Cleavage of an a-amino acid ester by a lipophilic Cu(II) complex incorporated into micelles of a cationic surfactant. A sector of a spherical micelle with incorporated ligand is shown schematically. (From Ref [12].)... Fig. I Cleavage of an a-amino acid ester by a lipophilic Cu(II) complex incorporated into micelles of a cationic surfactant. A sector of a spherical micelle with incorporated ligand is shown schematically. (From Ref [12].)...

See other pages where Sector spherical is mentioned: [Pg.187]    [Pg.429]    [Pg.262]    [Pg.16]    [Pg.456]    [Pg.258]    [Pg.22]    [Pg.131]    [Pg.59]    [Pg.125]    [Pg.446]    [Pg.485]    [Pg.153]    [Pg.99]    [Pg.295]    [Pg.63]    [Pg.91]    [Pg.256]    [Pg.269]    [Pg.676]    [Pg.191]    [Pg.881]    [Pg.263]    [Pg.17]    [Pg.433]    [Pg.174]    [Pg.430]    [Pg.479]    [Pg.6]   
See also in sourсe #XX -- [ Pg.16 ]




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