Direct hit

FIGURE 1.6 Rutherford s model of the atom explains why most u particles pass almost straight through the platinum foil, whereas a very few—those scoring a direct hit on the nucleus—undergo verv large deflections. Most of the atom is nearly empty space thinly populated by the atom s electrons. The nuclei are much smaller relative to their atoms than shown here. 

Figure 5. Development of knowledge base rules to select column and mobile phase constituents. indicates "direct hit".

In artists studios, which serve as a model for many of the interiors, there were generally one or two windows, usually on the north side of the room to keep sunhght from directly hitting the canvas. Some artists used wax paper or curtains to block out light or manipulate where it would fall. See W. Martin Boschloo. 

Compare to cross section 3.99 x 10-21 cm2, capturing neutrons acts as if it has a much larger cross section than its geometric cross-section i.e., a direct hit is unnecessary. 

Although the kinetic rate and energy partitioning are qualitatively consistent with a pure ER process, other aspects of the experiments and most of the theory (see discussion below) imply that the abstraction is more properly described as a combination of ER and HA reactions. The large a for abstraction is inconsistent with theoretical studies of a pure ER process as this requires a direct hit of the incoming H(D) with the adsorbed D(H) [380,381]. There is also no way to reconcile formation of homonuclear products with a pure ER process. In addition, similar kinetic experiments on other metals, e.g., Ni(100) [146], Pt(lll) [147,382], etc., are not even in qualitative agreement with the simple ER rate law above. In those cases, it is necessary to develop more sophisticated HA kinetic mechanisms to describe the kinetics experiments [383-385]. The key parameter of these kinetic models is the ratio of reaction to non-reactive trapping, pr/ps. For pr/ p, = 1, the HA kinetics looks very much like the simple ER case, and this is the reason H(D) + D(H)/Cu(lll) has such simple kinetics. 

Astonishingly, the screening results not only showed a trend of enatioselectivi-ties but also gave us a very direct hit. 

All modern means of combat, although they appear intended to kill the enemy, actually owe their success to the intensity with which they affect the psychic stability of the enemy... which in a decisive moment, induce the enemy to lose the will to fight and feel deflated... Life in a trench subject to direct hit or cave-in is a terrific strain on human nerves, but the experience of war has taught us that the strain becomes tolerable... Exactly the reverse is true of the... 

Such surface diffusion provides a mechanism whereby the active patched, covering but a small fraction of the surface, may be supplied with molecules of a reacting gas very much more rapidly than they could be supplied by direct hits from the vapour phase surface diffusion (see Chap. VI, 4) may bring molecules up to any kind of active patch. 

Rutherford knew from these results that the plum pudding model for the atom could not be correct. The large deflections of the a particles could be caused only by a center of concentrated positive charge that contains most of the atom s mass, as illustrated in Fig. 2.12(b). Most of the a particles pass directly through the foil because the atom is mostly open space. The deflected a particles are those that had a close encounter with the massive positive center of the atom, and the few reflected a particles are those that made a direct hit on the much more massive positive center. 

In ite of a previous report to the contrary, Guas and Chambe --lain discovered that styrene oxftle could be converted directly hit styrene episulfide by the thiocyanate route (Eq. 678). 

Prepare an alternative position. The Germans used tracked guns to blow a house to pdeces no amount of strengthening will withstand a direct hit. 

We screened over 10,000 fragments of a custom-built fragment library [7] at high concentrations (100 pM-1 mM each) in cocktails of 12 to identify active-site-directed hits by 15N-HSQC NMR [104], About half of these fragments were strictly rule-of-three compliant [20], whereas a large majority followed reduced complexity rules (MW < 350, cLogP < 2.2, H-bond donor < 3, H-bond acceptor... 

Germans opened fire direct hits broke several of the gas cylinders, the trench filled with gas, the gas-company stampeded. ... 

Chemistry is the science of change. It is ironic then that, although we have become so knowledgeable about the properties of reactants and products—about the beginnings and ends of chemical journeys—we remain more often than not unsure of just how those journeys are made. Our modern armory of sophisticated spectroscopic and diffraction methods provides every expectation of a direct hit on the fixed objects represented by reactants and products, but is seldom... 

Supports that do not directly participate in a catalytic reaction can increase the rate of catalysis indirectly by providing additional areas on which reacting molecules can be captured. Molecules adsorbed by physical forces on inactive areas may retain sufficient mobility to enable them to migrate over the surface and rapidly reach an active center.31 The active centers are thus supplied with reacting molecules more rapidly than could occur by direct hits from a vapor or solution phase. 

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