Arrows, curved

FIGURE 11.1 The kinetic curves of cumyl hydroperoxide formation in emulsion oxidation of cumene [8] at T — 358 K, H20 RH — 3 l (v/v) 1 N Na2C03 with input of 0.015mol L 1 H202 in the moments designated by arrows (curve 1), after 8 h (curve 2), and after 4 h (curve 3). 

Figure 7. Counting rate vs. time plots for Pt electrode in anhydrous solution of KCIO4 in DMSO containing 0.025 cm of HTO before (curve 1) and after (curve 2) an addition of unlabeled H2O in large excess (0.5 cm ). The moment of addition is marked with a vertical arrow. Curve 3 shows the counting rate dependence recorded after 0.5 cm of H2O was added first to the solution, followed the addition of 0.025 cm HTO. (Note that, as expected, the same final counting rate is reached with both procedures.) E = 0.30 V vs. sc e, ...

Grassmann diagram for the Linde liquefaction process of methane. One thousand exergy units of compression energy result in 53 exergy units of liquid methane. The thermodynamic efficiency of this process is 5.3%. The arrowed curves, bent to the right, show the losses in the various process steps. 

Figure 4. Plots of l (curve 1) and of l obtained from Eq. (53) (curve 2) against E for iodide adsorption on Ag(lll). The horizontal arrow (curve 3) denotes the I value obtained from Eq. (52) over the potential range of stability of the iodide adlayer. (Reprinted from Ref.7 with permission from the Am. Chem. Soc.)...

Fig. 4. Structural model for the chlorosome-reaction center complex of filamentous green bacteria. BChl molecules In chlorosome and cytoplasmic membranes are represented by squares. Direction of the transition dipole moment of the lowest excited singlet state of the respective pigment complex or molecules is represented by a straight arrow. Curved arrows show direction of energy transfer. See text for other details. Figure source same as Figure 2 in this chapter.

Use of Curved Arrows Curved arrows are used to describe the movement of electrons in a reaction mechanism. The arrow starts with the electron(s) to be moved and ends at the atom or bond where they move. Full arrows are used to denote the movement of electron pairs and fish hook arrows are used to show the movement of single electrons. ... 

Fig. 10 Typical time coiu se of frequency changes of the dsDNA 1-immobilized QCM, responding to the addition of ATP-dependent DNase and ATP at arrows. Curve a DNase was added at first, and then ATP was excessively added after the enzyme bound. Curve b DNase was added in the presence of excess ATP. Conditions 66.7 mM Glycine-NaOH buffer, pH 9.4, 30 mM MgCl2, 8.4 mM 2-mercaptoethanol, 0.1% Nonidet P-40 (ethylphenyl polyethyleneglycol), 30 °C, [DNase] = 138 nM, [ATP] = 0.5 mM...

Fig. 12.7. Tertiary (thin arrow). Secondary (grey arrow). Primary (thick arrow) curves are all still kyphotic, but the distal tip is bent to point downward (arrowhead)...

A conformation can be identified by a dihedral angle, which is the angle made by two bonds on adjacent atoms when the adjacent atoms are eclipsed in a Newman projection. Consider a C—C unit with substituent A on one carbon atom and substituent B on the other. The dihedral angle is the angle between the lines A-C and C-B in the Newman projection. The angle is considered positive if the arrow drawn from the near bond line curves clockwise toward the second bond line and negative if the arrow curves counterclockwise. 

We can show the transfer of a proton from an acid to a base by using a symbol called a curved arrow. Curved arrows will be used throughout your study of organic chemistry to describe how reactions proceed. Therefore, it is very important that you become proficient in their use. 

Fig. 2. (Comparison of the theoretical diffusion curves and actual sedimentation diagrams for E. colt bacteriophage T6 at pH 4.9. The solid line curves represent the mean ordinate of the sehlieren curve (corrected for camera magnification) and the circles denote the theoretical boundary diagram calculated from the diffusion constant. The position of the meniscus is given by the vertical arrow. Curves are given for 6280, 7200, and 10,080 seconds after the beginning of acceleration to 3150 r.p.m. (255).

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