Left-to-right convention

LEE-WILSON TREATMENT LEFFLER S ASSUMPTION HAMMOND POSTULATE Left-to-right convention,... 

Figure 2.19 Schematic representation of the different hierarchical nanocomposites (from left to right, conventional plant fibers-reinforced nanocomposites, BC coated fiber-reinforced nanocomposites and BC coated fibers-reinforced hierarchical nanocomposites). Reproduced with permission from [170].

Convention 1 For the ceU as written the oxidation process occurs on the left and reduction, on the right. Electrons move through the external circuit from left to right conventional current proceeds in the opposite direction. The redox reactions are schematized through the following half reactions At the anode (left) /4H2(P) = + e (Z). The extra ions produced in this process are... 

Traditionally, the electron and proton transport pathways of photosynthetic membranes (33) have been represented as a "Z" rotated 90° to the left with noncycHc electron flow from left to right and PSII on the left-most and PSI on the right-most vertical in that orientation (25,34). Other orientations and more complex graphical representations have been used to depict electron transport (29) or the sequence and redox midpoint potentials of the electron carriers. As elucidation of photosynthetic membrane architecture and electron pathways has progressed, PSI has come to be placed on the left as the "Z" convention is being abandoned. Figure 1 describes the orientation in the thylakoid membrane of the components of PSI and PSII with noncycHc electron flow from right to left. 

Numbering the particles in (87) from left to right, the conventional acid dissociation constant is defined at infinite dilution by... 

The event tree is written from left to right. The initiating event is written first in the center of the page on the left. A line is drawn from the initiating event to the first safety function. At this point the safety function can either succeed or fail. By convention, a successful operation is drawn by a straight line upward and a failure is drawn downward. Horizontal lines are drawn from these two states to the next safety function. 

We conventionally cite the oxidized form first within each symbol, which is why the general form is o,r> so pb4+ Pb + is correct, but 2+ 4+ is not. Some people experience difficulty in deciding which redox state is oxidized and which is the reduced. A simple way to differentiate between them is to write the balanced redox reaction as a reduction. For example, consider the oxidation reaction in Equation (7.1). On rewriting this as a reduction, i.e. Al3+(aq) + 3e = A Em, the oxidized redox form will automatically precede the reduced form as we read the equation from left to right, i.e. are written in the correct order. For example, o,r for the couple in Equation (7.1) is Ai3+,ai-... 

The three-phase equilibria correspond to two types of reactions, represented by the following equations conventionally written in order to indicate (from left to right) the transformation occurring on cooling. 

Half reactions are by convention, always written as reductions, that is showing addition of electrons going from left to right. Take careful note of the signs. When balancing the two half reactions however, one of them must be written as an oxidation. 

There are 10 base pairs in a complete turn of the helix, which spans a distance of 3.4 nm. The outside diameter of the helix is about 2nm. By convention, the double stranded DNA sequence is written from left to right the 5 end (position 5 of the sugar group) is assigned to the top left-hand strand. 

If we adopt the convention of writing the chemical reaction in the cell as occurring so that electrons will move in the outside conductor from left to right, so that the reaction in the left electrode is an oxidation and the reaction in the right electrode is a reduction, the reaction at the left electrode is... 

The base sequence of a nucleic acid strand is written by convention, in the 5 - 3 direction (left to right). According to this convention, the sequence of the strand on the left in Figure 1-1-8 must be written... 

The absence from a formula of any one of the horizontal or vertical lines at a chiral or prochiral carbon atom (as in examples on pages 27 and 32), or of or Z designations at double bonds, indicates that the configuration of that stereoisomeric centre is not known. Also, as in our previous document [2], the convention of orienting polymer structures (and the corresponding constitutional and configurational units) from left to right is used. Thus, the two bracketted constitutional units in... 

Following the convention in gas adsorption-desorption isotherms, the mercury isotherm, illustrated in Fig. 12.5, is plotted as volume versus relative pressure so that the radius increases from left to right. Curve I in Fig. 12.5 represents the condensation isotherm from the extrusion curve and curve II is the evaporation isotherm from the intrusion data. Since no adsorption takes place on the pore walls prior to the filling of pores in mercury porosimetry as occurs in gas adsorption, the usual knee of the isotherm is absent. However, condensation-evaporation isotherms from mercury porosimetry are strikingly similar to adsorption-desorption... 

This displays the convention, tacitly assumed later, that the positive direction of a step corresponds to the advancement from left to right of the stated chemical equation. The matrix of stoichiometric coefficients for these reactions is shown in Table II. The diagonalization of the matrix in Table II gives the matrix in Table III, from which the steady-state mechanism is S + 2s2 + 2s3 + 2s4. In Horiuti s terminology the stoichiometric numbers are 1 for Sj and 2 for s2, s3, and s4. 

Let us now apply Hiickel MO theory to the particular case of the allyl system, C3H3, as illustrated in Figure 4.2. Because we have three carbon atoms, our basis set is determined from convention (a) and will consist of 3 carbon 2p orbitals, one centered on each atom. We will arbitrarily number them 1, 2, 3, from left to right for bookkeeping purposes. 

In spectroscopic convention, the upper energy state is written first followed by the lower energy state between which the transition is taking place. For absorption, the arrow points from left to right, e.g. for the lowest energy transition in benzene at 260 nm, in absorption 1B2u - 1A,t and in emission ih - Mw. Other nomenclatures are given in the Table 3.4. 

FIGURE 26-3 Organization of coding information in the adenovirus genome. The genetic information of the adenovirus genome (a conveniently simple example) is encoded by a double-stranded DNA molecule of 36,000 bp, both strands of which encode proteins. The information for most proteins is encoded by the top strand—by convention, the strand transcribed from left to right—but some is encoded by the bottom strand, which is transcribed in the opposite... 

---