Double Hemisphere

Maeda, K. Semeluk, G.P. Lossing, F.P. A Two-Stage Double-Hemispherical Electron Energy Selector. Int. J. Mass Spectrom. Ion Phys. 1968,1, 395-407. 

Earlier estimates of ionization potentials obtained with conventional mass spectrometric ion sources were beset with difficulties caused by the relatively wide energy spread (0.5—1 eV) in the thermally produced electron beam. Refinements of the electron-impact method, such as use of an energy-resolved electron beam from a double-hemispherical electrostatic monochromator18 or the retarding potential difference (RPD) method19 afforded values which are in good agreement with photoionization and spectroscopic data. 

Lewis GEM, Dale SEC, Kasptzyk-Hordem B, Barnes EO, Compton RG, Marken F (2012) Square wave electroanalysis at double hemisphere junctions. Electroanalysis 24 1726-1731... 

The momentum microscope is a combination of a conventional PEEM column, which serves as an input to a double-hemispherical imaging electron energy analyser, shown schematically in Figure 8.8. The addition of the energy... 

These modes of operation ate used in conjunction with the two most popular energy analyzers, the cylindrical mirror analyzer (CMA) and the concentric hemispherical analyzer (CHA). The most common form of the CMA used today is the double-pass version diagramed in Eigute 21. This device consists of two perfectly coaxial cylinders of radii r and r. The outer cylinder is held at a potential of (— ) and the inner cylinder is held at ground. The... 

Addition reactions — The fullerenes Ceo and C70 react as electron-poor olefins with fairly localized double bonds. Addition occurs preferentially at a double bond common to two annelated 6-membered rings (a 6 6 bond) and a second addition, when it occurs is generally in the opposite hemisphere. The first characteriz-able mono adduct was [C6oOs04(NC5H4Bu )2]. formed by reacting Cgo with an excess of OSO4 in 4-butylpyridine. The structure is shown in... 

The 10-degree warming in the northern waters is thought to be part of a warming trend across a broad part of the Northern Hemisphere. This caused increased precipitation that was far reaching. In Greenland, the thickness of the annual ice layers showed that snowfall doubled in a single year. 

The DigiSim program enables the user to simulate cyclic voltanunetric responses for most of the common electrode geometries (planar, full and hemispherical, and full and hemicylindrical) and modes of diffusion (semiinfinite, finite and hydrodynamic diffusion), with or without inclusion of IR drop and double-layer charging. 

Bowen and Masliyah examined the axial resistance of cylinders with flat, hemispherical and conical ends, and of double-headed cones and cones with hemispherical caps, together with the established results for spheroids. Widely used shape factors (including sphericity) did not give good correlations, while Eqs. (4-26) and (4-27) were found to be inapplicable to particles other than cylinders and spheroids. The best correlation was provided by the perimeter-equivalent factor Yj defined in Chapter 2. With this parameter, the equivalent sphere has the same perimeter as the particle viewed normal to the axis. Based on their numerical results, Bowen and Masliyah obtained the correlation... 

Since there are up to 30 reactive double bonds in the C6o molecule, a great number of polyadducts are possible. For a description of the spatial arrangement of the addends the C6o molecule is divided into three sections with regard to the location of the second attack [208], The second attack can take place on the same hemisphere (cis), at the equator (e), or on the opposite hemisphere (trans). For example, for the addition of an identical second addend eight regioisomeric bisadducts are possible as shown in Fig. 28. 

The itinerary of isomerizations by the double turnstile rotation, or (TR)2 is shown in Fig. 9. Figure 9 corresponds to isomerizations when the five ligands are different. The lines connect isomers which fall on the same hemispheres. There are no connections between isomers which fall on different hemispheres i.e., there can be no inversions. Each isomer is connected to six others by (TR)2. The isomers that were connected by... 

Fio. 9. Itinerary for permutational isomerizations by double turnstile rotation, when the five ligands in trigonal bipyramidal phosphorus are different. Isomers are identified by both Permutational and Binary Notations. There are no connections between isomers in upper and lower hemispheres. 

Ultramicroelectrode (UME) — an - electrode having a characteristic dimension less than 25 pm. This characteristic dimension refers to a diameter for a disk, a sphere, a hemisphere, and a cylinder, and a width for a band UME, for example. Conceptually, the lower limit of the characteristic dimension of a UME is about 10 nm, which corresponds to the thickness of the - double layer or the size of molecules. Electrodes of such dimensions are sometimes referred to as - nanoelectrodes or nan-odes. Electrodes with a characteristic dimension ranging from 25 pm up to approximately 1 mm are referred to as -> microelectrodes. Electrodes with dimensions of millimeters, centimeters, or meters have been referred to... 

The efficacy and safety of clomethiazole (75 mg/kg by intravenous infusion over 24 hours), as a neuroprotective drug, were studied in a double-blind, placebo-controlled trial (CLASS, the Clomethiazole Acute Stroke Study) in 1360 patients with acute hemispheric stroke (4). Clomethiazole was generally well tolerated and safe. Sedation was the most common adverse event, leading to treatment withdrawal in 16% of patients compared with 4.2% of placebo-treated patients. 

There is growing evidence that the composition of the troposphere is changing. For example, analysis of historical ozone records has indicated that tropospheric ozone levels in both hemispheres have increased by a factor of 3-A over the last century. Methane concentrations have effectively doubled over the past 150 years and N2O levels have risen by 15% since pre-industrial times.Measurements of halocarbons have shown that this group of chemically and radiatively important gases to be increasing in concentration until relatively recently. 

Mobius strip. In this way the antimatter mystery disappears matter and antimatter are one and the same thing, which merely appear to be different depending on their position in the double cover. In more dimensions the Mobius model is replaced by a projective plane, obtained from an open hemisphere on identifying points on opposite sides of the circular edge. Topologically equivalent constructs are known as a Roman surface or a Klein bottle. 

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