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Derivatives quotient

Indeterminate Forms UHospital s Theorem Forms of the type 0/0, oo/oo, 0 X oo, etc., are callea indeterminates. To find the limiting values that the corresponding functions approach, L Hospital s theorem is useful If two functions/(x) andg(x) both become zero at X = a, then the hmit of their quotient is equ to the hmit of the quotient of their separate derivatives, if the limit exists or is -i- oq or — oo. [Pg.443]

The dimensionless groups can be replaced by the corresponding differential quotient expressions for the derivatives as ... [Pg.189]

The eomputer program PROG52 ean be used to solve any number of nonlinear equations. The partial derivatives of the funetions are estimated by the differenee quotients when a variable is perturbed by an amount equal to a small value (A) used in the program to perturb the X-values. [Pg.334]

The first step is to reconstruct the data table to include derived mass fraction data and sums and quotients required for the calculation of mean. This is conveniently achieved by means of a spreadsheet. [Pg.22]

The measure used to describe the potential for noncarcinogenic toxicity to occur in an individual is not expressed as tlie probability of an individual suffering an adverse effect. The EPA does not at tlie present time use a probabilistic approach to estimate tlie potential for noncarcinogenic healtli effects. Instead, tlie potential for non carcinogenic effects is evaluated by comparing an exposure level over a specified time period (e.g., lifetime) witli a reference dose derived for a similar exposure period. Tliis ratio of exposure to toxicity is called a liazard quotient and is described below. (The reader is referred to Chapter 11 for additional details on tlie material tliat follows). The noncancer liazard quotient assumes tliat tliere is a level of exposure (i.e., RfD) below which it is unlikely for even sensitive populations to experience adverse healtli effects. [Pg.398]

If the HI is greater diaii unity as a consequence of summing several haz,ard quotients of similar value, it would be appropriate to segregate the compounds by effect and mechanism of action and to derive separate luizard indices for each group. [Pg.400]

The potential for noncarcinogcnic health effects is evaluated by comparing iui exposure level over a specified lime period (c.g., lifetime) with a reference dose derived for a similar exposure period. The ratio of exposure to toxicity in called a liazard quotient and, when it is greater tlien unity tlierc is a higher level of concern for potential noncancer effects. [Pg.419]

The quotient can be derived from the maximum yield for oxygen (Y ) using the equation ... [Pg.49]

Diazoalkanes add readily to the double bond of esters of vinylphosphonic acid, giving the pyrazoline derivatives (100), which can lose nitrogen to give esters of cyclopropylphosphonic acids. In a similar reaction, acyl-phosphonic acid esters (101) were converted to epoxy-derivatives (102). A -Phenylsydnone adds to diethyl prop-l-ynephosphonate, giving the pyra-zole (103). The addition of cyclopentadiene to dimethyl vinyl phosphate leads to an exojendo quotient of 1.2, but with hexachlorocyclopentadiene only e/ii/o-isomer is formed. ... [Pg.117]

The basic relationships between solubility and pH can be derived for any given equilibrium model. The model refers to a set of equilibrium equations and the associated equilibrium quotients. In a saturated solution, three additional equations need to be considered, along with the ionization Eqs. (2a)-(2d), which describe the equilibria between the dissolved acid, base or ampholyte in solutions containing a suspension of the (usually crystaUine) solid form of the compounds ... [Pg.68]

The question arises as to whether comparisons with protein enzymes are justified. In other words, what can ribozymes really do An important parameter for measuring the efficiency of enzymes is the value of kc-JK. This quotient is derived from the values of two important kinetic parameters kc-Al is a rate constant, also called turnover number, and measures the number of substrate molecules which are converted by one enzyme molecule per unit time (at substrate saturation of the enzyme). Km is the Michaelis-Menten constant it corresponds to the substrate concentration at which the rate of reaction is half its maximum. [Pg.163]

The ideal gas hypothesis is avoided by equation 2.34. Moreover, to derive this equation, it has been assumed that the quotient A pH/Z is constant in the experimental temperature range. Now this ratio divided by the gas constant (R) is equal to the slope of the correlation, which implies that A VH can be evaluated at a given temperature if Z is known. [Pg.24]

Figure 4-25. The top panel displays the true derivatives and those computed as the quotient of differences the middle and bottom panels show the result of a 2nd and 4th degree polynomial fitted through 11 data points. Figure 4-25. The top panel displays the true derivatives and those computed as the quotient of differences the middle and bottom panels show the result of a 2nd and 4th degree polynomial fitted through 11 data points.
Work by Voit and his associates continued so that by 1900 standard values for heats of combustion of different foods had emerged (Table 1). Respiratory quotients (RQ) were also derived, associated with the utilization of the different foods. The RQ is the molar ratio of the amount of carbon dioxide produced in the oxidation of a substance to the amount of oxygen needed for that oxidation. For carbohydrate the RQ is 1 ... [Pg.20]

SSLs are risk-based concentrations derived from standardized equations combining exposure information assumptions with US-EPA toxicity data. For the ingestion, dermal, and inhalation pathways, toxicity criteria are used to define an acceptable level of contamination in soil, based on a one-in-a-million (10 individual excess cancer risk for carcinogens and a Hazard Quotient (HQ) of 1 for noncarcinogens. The hazard quotient is defined as the ratio of an exposure estimate over the Reference Dose or Concentration (Section 5.1), i.e., HQ = Exposure/(RfD or RfC). [Pg.364]

A useful trial variational function is the eigenfunction of the operator L for the parabolic barrier which has the form of an error function. The variational parameters are the location of the barrier top and the barrier frequency. The parabolic barrierpotential corresponds to an infinite barrier height. The derivation of finite barrier corrections for cubic and quartic potentials may be found in Refs. 44,45,100. Finite barrier corrections for two dimensional systems have been derived with the aid of the Rayleigh quotient in Ref 101. Thus far though, the... [Pg.10]

The principal data available to determine or E directly from ifpdO) are conversion coefficients which give the quotient of or E and /fp(lO) [i.e., He/[Hp(10)1 or /[ifp(10)]). The unit for each of the three quantities is Sv therefore, these conversion coefficients are dimensionless. Such conversion coefficients have been derived from calculations for a number of idealized conditions for irradiation by monoenergetic photons of mathematically described reference adult anthropomorphic phantoms. The conversion coefficients are a function of photon energy, photon beam direction, surface of the phantom on which the radiation is incident, and location where //p(lO) is being evaluated on the phantom. [Pg.17]

The basic principle in this technique is to replace derivatives by finite differences, i.e., dy/dx is replaced by Ay/Ax. The differential equation is then rewritten using these difference quotients in place of the derivatives and the boundary conditions of the problem introduced. The equations can then be solved analytically. Space and time... [Pg.444]

The E factor, and derived metrics, takes only the mass of waste generated into account. However, the environmental impact of waste is determined not only by its amount but also by its nature. Hence, we introduced [13] the term environmental quotient , EQ, obtained by multiplying the E factor by an arbitrarily... [Pg.6]

The familiar rules for combining derivatives with sums, products and quotients apply to complex-valued functions. [Pg.22]

For t2, therefore, we need the derivative of the imaginary part of the eigenvalues evaluated at the Hopf bifurcation point. We may also note that the sign of the quotient t2//r2 is of less immediate significance than those of / 2 and n2. [Pg.122]

When X = C2, X can be identified with the set of GLJl(C)-orbits of (Hi, B2, i) where Bi, B2 are commuting n x n-matrices and i is a cyclic vector (Theorem 1.14). Many properties of (C2) are derived from this description. In Chapter 3, we shall regard the description as a geometric invariant theory quotient and a hyper-Kahler quotient. This description is very similar to the definition of quiver varieties which were studied in [62]. [Pg.1]

If we define D = y2/2-r as the quotient between the mean square displacement y2 and the time span 2-r and name it the diffusion coefficient, we have derived Fick s second law... [Pg.69]

We can now derive a relationship between free energy and the equilibrium constant. At equilibrium, AG for a reaction is zero and the reaction quotient Q equals the equilibrium constant K. Substituting AG = 0 and Q = K into the equation... [Pg.747]

The derivation of the law of mass action from the second law of thermodynamics defines equilibrium constants K° in terms of activities. For dilute solutions and low ionic strengths, the numerical values of the molar concentration quotients of the solutes, if necessary amended by activity coefficients, are acceptable approximations to K° [Equation (3)]. However, there exists no justification for using the numerical value of a solvent s molar concentration as an approximation for the pure solvent s activity, which is unity by definition.76,77... [Pg.348]

Consider a real function y = f(x) of a real variable x. By this we mean a mapping of the real number x to a unique real number y, given by the rule /. Furthermore, let us assume it to be continuous. We will introduce the concept of the derivative of f(x) with respect to x in terms of the slope of the tangent line at the point x,f(x)). In order to do this, we need to consider three simple constructive rules using the slope of a straight line as our starting point, and Leibniz rule as our keystone. The slope is calculated as a ratio of two displacements rise over run . Hence, we define the derivative of y with respect to r as a quotient of the two corresponding differentials, denoted by dy (the rise ) and dx (the run ) ... [Pg.109]

We have dealt with the sum and the product of functions, as well as the quotient. In order to calculate the derivative of the composition of two functions, we take advantage of the fact that the derivative is defined as the quotient of two differentials. In the case in which / is a function of u, in turn a function of x, the chain rule will tell us how to calculate the derivative of f(u(x)) with respect to x simply as ... [Pg.114]


See other pages where Derivatives quotient is mentioned: [Pg.308]    [Pg.92]    [Pg.1235]    [Pg.225]    [Pg.18]    [Pg.134]    [Pg.229]    [Pg.642]    [Pg.245]    [Pg.411]    [Pg.115]    [Pg.81]    [Pg.347]    [Pg.567]    [Pg.37]    [Pg.412]    [Pg.456]    [Pg.788]    [Pg.20]    [Pg.53]    [Pg.23]    [Pg.111]    [Pg.120]   
See also in sourсe #XX -- [ Pg.24 ]




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