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haoxin510 发表于 2006-5-23 01:46

跪求英文高手帮小弟翻译几段话~老师催~救命了

AbstractX2Y Yt(R8TGh/`)R
—The approximation of titration curves by logarithmic functions was described for the titration of a9e O\9U5k'|]*~m
mixture of two monobasic acids. It was demonstrated with the titration of a mixture of CHCl2COOH,CH2ClCOOH, C6H5COOH, and H3BO3
that this method can be used for the precise determination of equivalence
points. The relative error in the determination of titration end-points depends on the values of the corresponding
jumps and, to some extent, on the choice of a weight function and lies in the range from 0.1 to 1%.#d@3F9Z:{%NVoq
At present, two groups of computer-assisted methods
are used for the determination of equivalencet^k-vX H7U
points in potentiometric titration.
Methods [1–3] based on the approximation of a
titration curve by polynomials and followed by the
determination of their inflection points comprise the
first group. The polynomial approximation has no`P@7m.r-rSg[7Qe
physical meaning and is undesirable for use in the`ctF4lu
determination of titration end-points in the case when
inflection points in the jump region do not coincide
with equivalence points. In spite of this, the simplicity%?JFh!N7q'r/[
and versatility of this approximate approach requiring
a minimum of calculations make it an attractive tool for
processing titration curves of different nature.
The second group includes a greater number of
methods (see, for example, [4–9]). The use of materialu6SU}~a8_-j
balance equations and the law of mass action for processing
the data of potentiometric titration not only
solves the main problem of titrimetry, highly precise+q6|d7nr ^{)@
determination of titration end-points, but also providesYl-SO4] pU$c4D;\
the calculation of equilibrium constants for titrationI{r#g-c%H
reactions in many cases. Depending on specific conditions,
the the disadvantages of these methods may be as
follows:$^V$F8K.G&f;UM
(1) The method is intended for a particular type of
titration.)L,R*Y }~U;G
(2) Only a part of the data is used for the determination
of titration end-points (in the methods based on theVEF?1`&G%Hj
linearization of a titration curve).N7F%{7S)D
(3) Low repeatability and, in specific cases, even the
abnormal termination of calculations (for instance, inwr.O0t2b
processing titrations of acids of an intermediate
strength in dilute solutions).dFR c7G'`(P
Recently, using titration curves of different natures}Z/P"a1ow A
with a single equivalence point as an example, the(m8M ?R^%o[3x
author has shown [10–12] that the main merits of thej^Gt&Z)]Ia"E `
methods of both groups can be retained if the approximation of the titration curves is carried out by logarithmic
functions, whose parameters have physical meaning,-j/n2WRB p#sf
rather than by polynomials.
In this work, we studied the use of logarithmic functions
for the precise determination of equivalence t Q7M8TQ3p
points in more complicated titrations, namely, in titrations
of mixtures of two monobasic acids. Here, as5ws pCU1o+x Y;]
before, it was assumed that the ionic strength of aB { TG0O-Q4H`6@7a
titrated solution remained virtually the same on theV7A;`6R@:{(v F-^
addition of a titrant.

haoxin510 发表于 2006-5-23 01:48