Specificity constant meaning

We thus label heat capacity as Cp, meaning the thermal capacity at constant pressure. Sometimes, it is also called specific heat, meaning the ratio of thermal capacity of any given material to that of water, defined as 1.000. 

A mixture of Me3210PbCl and 210Pb(NO3)2 was used to study the rate of ionic trimethyl-lead uptake by exposed plant surfaces. More specifically, the mean cumulative activity of the lead toxicants transferred across tomato cuticle was measured daily over a six-day period. Reversed-phase HPLC was used to separate and identify the lead species crossing the plant cuticle. It was found that appreciably more trimethyllead(I) (75% of the theoretical) than inorganic lead(II) (39%) was transferred. The apparent rate constants derived from the first-order plot of time in days versus the difference in observed activity were 0.0788 and 0.0346 day-1 for transfer of the trimethyllead(I) and inorganic lead(II), respectively. 

Care a supermarket uses the word strong in a different way from chemists remember from Chapter 6 that the everyday word strong has the specific chemical meaning a large equilibrium constant of dissociation. ... 

Planning the eaperiments is the next step after the hypothesis has been formulated and a sofeion has been proposed (see Figure 2.1). This includes planning what datam collect and how it is collected. Specifically, this means determining the nm er, identity, and order of samples to analyze, what is to be measured, whasis to be held constant, how the data will be collected, and any other factors tha affect the data that are generated. 

Conversely, if [S] < C Km, (Eq. (2.42)) reduces to v = (k2/Km)[E]o[S]. This means that the active sites on the enzyme are effectively unoccupied. The ratio k2/Km is also known as the enzyme s specificity constant, a measure of the enzyme s affinity for different substrates. Thus, if the same enzyme can catalyze the reaction of two substrates, S and S, the relative rates of these two reactions are compared using (k2/Km)s (k2/Km)s-. Because the specificity constant reflects both affinity and catalytic ability, it is also used for comparing different enzymes. 

After centering, each observation has zero mean but different variances. In scaling, each observations is divided by a column-specific constant, usually the standard deviation (s)... 

For the purposes of our discussion we shall look in turn at the uses of each term in Eqn. 6. The Cq term should be noted to be a velocity (units are concentration or amount/time) and not a rate coefficient. The terms and K (whose components can sometimes be dissected by means of fast reaction techniques, vide infra) are used to describe the sensitivity of the enzyme reaction to a variety of changes, as described above. Their ratio k yK, with dimensions of a second-order rate coefficient (M sec ) is also useful and has been called the specificity constant by Brot and Bender [4]. For a single, covalent intermediate pathway (e.g. Eqn. 7, e.g. an acyl-enzyme pathway, this composite constant is insensitive to problems such as non-productive substrate binding, whilst its components are complicated by such problems. 

The most important conclusions from these figures are (i) the pH at the buffer point increases with increasing p/sTa values, (ii) the pH at the equivalence points increases with increasing p/sTa values, and (in) the pH jump around the equivalence point, defined as ApH between t = 0.99 and t = 1.01, decreases with increasing p/sTa values. The latter means that the slope decreases also with increasing p/sTa values, which leads to increasing random errors, as any indication always relates to a specific constant ApH (see further down the discussion of random errors of titrations). 

For coastal waters in open communication with the sea, the mean water level (MWL) can often effectively be taken as a site-specific constant, being related to the mean sea level (MSL) of the oceans. In some areas, for example the eastern Mediterranean, the mean sea level varies slightly with the time of year, in a predictable way. 

Aliphatic backbone polymers have n backbone bonds, with a well-defined average backbone bond length /, and known backbone bond angle 0, making / max = /cos (0/2) in the zR-trans conformation. Flory defined [15] the characteristic ratio Coo as the ratio of the actual tmperturbed mean-square end-to-end distance o and that of a freely jointed chain nfi, which is a polymer-specific constant at large M... 

The spatially reduced capacitances that are specific of the medium are electric permittivities in this energy variety. To each capacitance at the global level corresponds an electric permittivity and, therefore, the equality D4.6 corresponds to an equality between mutual permittivities. Their common value is a scalar constant, meaning that the assumption of a homogeneous space constituting the system is made. 

Some examples of the first methodology are presented in Tables 1 to 4. In order to quantify the enantioselective performance in the resolution of enantiomers, the enantiomeric ratio ( ) is the parameter used in all of the tables. This value was first defined by Chen et al. [83] and measures the ratio between the specificity constants (Vmax/ m) for both enantiomers. (We strongly recommend that the reader consult tiie recent work of Straatiiof and Jongejan [84] for an exhaustive review on the meaning and calculation of E.) As it was defined, E values below 15 are insufficient for practical purposes E values between 15 and 30 are moderate to good, and values above these figures are excellent. 

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