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1.
Thermodynamic characteristics of alanine-18-crown-6 ether complexes in binary water-acetone solvents
T. R. Usacheva I. A. Kuz’mina V. A. Sharnin I. V. Chernov E. Matteoli 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2012,86(1):36-39
The formation of 18-crown-6 ether (18C6) complexes with D,L-alanine (Ala) in mixed wateracetone solvents with 0.0, 0.08, 0.17,
0.22, and 0.30 mole fractions of acetone (T = 298.15 K) was investigated by means of calorimetry. Thermodynamic characteristics of the reaction of the molecular [Ala18C6]
complex formation (Δr
G°, Δr
H°, and TΔr
S°) were calculated on the basis of calorimetric data. Analysis of solvation contributions of reagents into the enthalpy of
the [Ala18C6] formation reaction showed that the changes in the reaction energy when the solvent composition is varied are
determined by the changes in the solvate state of 18C6. 相似文献
2.
E. Matteoli L. Lepori T. R. Usacheva V. A. Sharnin 《Journal of Thermal Analysis and Calorimetry》2009,97(3):811-816
The influence of H2O–EtOH and H2O–Acetone mixed solvents at various compositions on the thermodynamics of complex formation reaction between crown ether 18-crown-6
(18C6) and glycine (Gly) was studied. The standard thermodynamic parameters of the complex [Gly18C6] (log K°, Δr
H°, Δr
S°) were calculated from thermochemical data at 298.15 K obtained by titration calorimetry. The complex stability and its formation
enthalpy increase with increasing the non aqueous component concentration in both mixed solvents. The thermodynamic data were
discussed on the basis of the solvation thermodynamic approach and the solvation contributions of the reagents and of the
complex to the complex stability were analyzed. 相似文献
3.
T. R. Usacheva Fam Tkhi Lan V. A. Sharnin A. Baranski 《Russian Journal of Inorganic Chemistry》2013,58(10):1264-1268
The influence of composition of H2O-EtOH solvent on the reaction of formation of a molecular complex of 18-crown-6 ether (18C6) with triglycine (3Gly) has been studied at 298.15 K by a thermochemical method. The standard thermodynamic parameters (Δr G°, Δr H°, and TΔr S°) of the reaction of [3Gly18C6] complex formation in water-ethanol (H2O-EtOH) solvents having an EtOH mole fraction of 0.0, 0.1, 0.15, 0.2, 0.25, 0.30, and 0.50 have been calculated from the data of calorimetric measurements performed on a TAM III titration microcalorimeter. It has been found that an increase in EtOH concentration in the mixed solvent results in an increase in stability of [3Gly18C6] and in an enhancement in exothermicity of its formation reaction. The water-ethanol solvent has an analogous effect on the stability and energetics of the reactions of formation of molecular complexes of 18C6 with glycine, D,L-alanine, and L-phenylalanine. 相似文献
4.
Edwin H. Battley 《Journal of Thermal Analysis and Calorimetry》2011,104(1):13-22
Calculations are made using the equations Δr
G = Δr
H − TΔr
S and Δr
X = Δr
H − Δr
Q where Δr
X represents the free energy change when the exchange of absorbed thermal energy with the environment is represented by Δr
Q. The symbol Q has traditionally represented absorbed heat. However, here it is used specifically to represent the enthalpy listed in tabulations
of thermodynamic properties as (H
T
− H
0) at T = 298.15 K, the reason being that for a given substance TS equals 2.0 Q for solid substances, with the difference being greater for liquids, and especially gases. Since Δr
H can be measured, and is tangibly the same no matter what thermodynamics are used to describe a reaction equation, a change
in the absorbed heat of a biochemical growth process system as represented by either Δr
Q or TΔr
S would be expected to result in a different calculated value for the free energy change. Calculations of changes in thermodynamic
properties are made which accompany anabolism; the formation of anabolic, organic by-products; catabolism; metabolism; and
their respective non-conservative reactions; for the growth of Saccharomyces cerevisiae using four growth process systems. The result is that there is only about a 1% difference in the average quantity of free
energy conserved during growth using either Eq. 1 or 2. This is because although values of TΔr
S and Δr
Q can be markedly different when compared to one another, these differences are small when compared to the value for Δr
G or Δr
X. 相似文献
5.
G. Xie S. P. Chen S. L. Gao X. X. Meng Q. Z. Shi 《Journal of Thermal Analysis and Calorimetry》2006,83(3):693-700
A novel solid complex, formulated as Ho(PDC)3
(o-phen), has been obtained from the reaction
of hydrate holmium chloride, ammonium pyrrolidinedithiocarbamate (APDC) and
1,10-phenanthroline (o-phen·H2O)
in absolute ethanol, which was characterized by elemental analysis, TG-DTG
and IR spectrum. The enthalpy change of the reaction of complex formation
from a solution of the reagents, ΔrHmθ (sol), and the molar heat capacity of the complex, cm,
were determined as being –19.161±0.051 kJ mol–1
and 79.264±1.218 J mol–1 K–1
at 298.15 K by using an RD-496 III heat conduction microcalorimeter. The enthalpy
change of complex formation from the reaction of the reagents in the solid
phase, ΔrHmθ(s), was calculated as
being (23.981±0.339) kJ mol–1 on the
basis of an appropriate thermochemical cycle and other auxiliary thermodynamic
data. The thermodynamics of reaction of formation of the complex was investigated
by the reaction in solution at the temperature range of 292.15–301.15
K. The constant-volume combustion energy of the complex, ΔcU, was determined as being –16788.46±7.74
kJ mol–1 by an RBC-II type rotating-bomb
calorimeter at 298.15 K. Its standard enthalpy of combustion, ΔcHmθ, and standard enthalpy of formation,
ΔfHmθ, were calculated to be –16803.95±7.74 and –1115.42±8.94
kJ mol–1, respectively. 相似文献
6.
I. N. Mezhevoi V. G. Badelin 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2008,82(4):683-685
The integral enthalpies of solution (Δsol
H
m
) of L-serine in water-alcohol (ethanol, n-propanol, isopropanol) mixtures were measured over the range of alcohol concentrations up to 0.32 mole fractions. The standard
enthalpy of solution (Δsol
H°), enthalpy of transfer of L-serine from water into a mixed solvent (Δtr
H°), and enthalpy of solvation (Δsolv
H°) were calculated. The dependences of Δsol
H°, Δsolv
H°, and Δtr
H° on the composition of mixtures had extrema. The calculated enthalpy coefficients of the pair interactions of L-serine with
alcohol molecules were positive and increased along the series ethanol, n-propanol, isopropanol. The data obtained were interpreted in terms of different types of interactions in solutions and the
influence of the nature of amino acid residues on the thermochemical solution characteristics.
Original Russian Text ? I.N. Mezhevoi, V.G. Badelin, 2008, published in Zhurnal Fizicheskoi Khimii, 2008, Vol. 82, No. 4,
pp. 789–791. 相似文献
7.
The novel ternary solid complex Gd(C5H8NS2)3(C12H8N2) has been obtained from the reaction of hydrous gadolinium chloride, ammonium pyrrolidinedithiocarbamate (APDC), and 1,10-phenanthroline
(o-phen · H2O) in absolute ethanol. The complex was described by an elemental analysis, TG-DTG, and an IR spectrum. The enthalpy change
of the complex formation reaction from a solution of the reagents, Δr
H
m
ϑ
(sol), and the molar heat capacity of the complex, c
m
, were determined as being − 15.174 ± 0.053 kJ/mol and 72.377 ± 0.636 J/(mol K) at 298.15 K by using an RD496-III heat conduction
microcalorimeter. The enthalpy change of a complex formation from the reaction of the reagents in a solid phase, Δr
H
m
ϑ
(s), was calculated as being 52.703 ± 0.304 kJ/mol on the basis of an appropriate thermochemical cycle and other auxiliary
thermodynamic data. The thermodynamics of the formation reaction of the complex was investigated by the reaction in solution.
Fundamental parameters, the activation enthalpy (ΔH
≠
ϑ
), the activation entropy (ΔS
≠
ϑ
), the activation free energy (ΔG
≠
ϑ
), the apparent reaction rate constant (k), the apparent activation energy (E), the preexponential constant (A), and the reaction order (n), were obtained by the combination of the thermochemical data of the reaction and kinetic equations, with the data of thermokinetic
experiments. The constant-volume combustion energy of the complex, Δc
U, was determined as being −17588.79 ± 8.62 kJ/mol by an RBC-II type rotatingbomb calorimeter at 298.15 K. Its standard enthalpy
of combustion, Δc
H
m
ϑ
, and standard enthalpy of formation, Δf
H
m
ϑ
, were calculated to be −17604.28 ± 8.62 and −282.43 ± 9.58 kJ/mol, respectively.
The text was submitted by the authors in English. 相似文献
8.
L. Peng X. Jiangjun M. Fangquan L. Xi Z. Chaocan 《Journal of Thermal Analysis and Calorimetry》2008,93(2):485-488
The standard molar enthalpy of combustion of cholesterol was measured at constant volume. According to value of Δr
U
mθ(−14358.4±20.65 kJ mol−1), Δr
H
mθ(−14385.7 kJ mol−1) of combustion reaction and Δf
H
mθ(2812.9 kJ mol−1) of cholesterol were obtained from the reaction equation. The enthalpy of combustion reaction of cholesterol was also estimated
by the average bond enthalpies. By design of a thermo-chemical recycle, the enthalpy of combustion of cholesterol were calculated
between 283.15∼373.15 K. Besides, molar enthalpy and entropy of fusion of cholesterol was obtained by DSC technique. 相似文献
9.
1. Results of thermodynamic and kinetic investigations for the different crystalline calcium carbonate phases and their phase
transition data are reported and summarized (vaterite: V; aragonite: A; calcite: C). A→C: T
tr=455±10°C, Δtr
H=403±8 J mol–1 at T
tr, V→C: T
tr=320–460°C, depending on the way of preparation,Δtr
H=–3.2±0.1 kJ mol–1 at T
tr,Δtr
H=–3.4±0.9 kJ mol–1 at 40°C, S
V
Θ= 93.6±0.5 J (K mol)–1, A→C: E
A=370±10 kJ mol–1; XRD only, V→C: E
A=250±10 kJ mol–1; thermally activated, iso- and non-isothermal, XRD
2. Preliminary results on the preparation and investigation of inhibitor-free non-crystalline calcium carbonate (NCC) are
presented. NCC→C: T
tr=276±10°C,Δtr
H=–15.0±3 kJ mol–1 at T
tr, T
tr – transition temperature, Δtr
H – transition enthalpy, S
Θ – standard entropy, E
A – activation energy.
3. Biologically formed internal shell of Sepia officinalis seems to be composed of ca 96% aragonite and 4% non-crystalline calcium carbonate.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
10.
L. A. Kochergina A. V. Emel’yanov 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2011,85(10):1742-1747
Heats of reaction of glycylglycine with nitric acid and potassium hydroxide solutions are determined by two calorimetric procedures
at 288.15, 298.15, 308.15 K and an ionic strength of solution of 0.25, 0.50, and 0.75 in the presence of KNO3. Standard thermodynamic characteristics (Δr
H°, Δr
G°, Δr
S°, and Δp
C°) are calculated for the acid-base reactions in aqueous peptide solutions. The effects of the concentration of background
electrolyte and temperature on the heats of dissociation of glycylglycine are considered. 相似文献
11.
T. Sillinger P. Than B. Kocsis D. Lőrinczy 《Journal of Thermal Analysis and Calorimetry》2005,82(1):221-223
Summary Treatment of a bacterial arthritis is a challenging task for a clinician as inadequate therapy can cause cartilage destruction
and can result in severe osteoarthritis of the affected joint. The development of cartilage destruction in septic arthritis
is not known in details. The aim of this study was to follow this process by calorimetric method. We induced experimental
septic arthritis in knee joints of seven New Zealand rabbits by single inocculation of Staphylococcus aureusOKI 112001 culture (1.5 mL 8·108±5% c.f.u.). The first rabbit died on the 11thday. At that time all the other subjects were made overslept and samples were isolated from the cartilage of the femurs for
calorimetric measurement. The DSC scans clearly demonstrated the development of infective structural destruction in cartilage
from the first to the tenth day of incubation. In case of healthy control the melting temperatures (Tm) were: 49.7, 55 and 63.4°C and the total calorimetric enthalpy change (ΔH) was 0.55 J g-1. After the first day the enthalpy decreased (0.375 J g-1), the first two transition temperature shifted towards higher temperature: 57 and 63.15°C. Up to the fourth day the effect
of infection culminated with Tmof 49.3, 55.9, 59.4, 62.8°C and further decrease of the ΔH. At the fifth day the effect of infection is culminated in two separable thermal denaturation events (with 55 and 63.3°C
Tms) with high jump in ΔHindicating the dramatic change of the structure of rabbit cartilage, so this time elapsed seems to be critical from the point
of view of practical clinical relevance too. Between the 7thand 11thdays practically we had same melting temperatures (50 and 63°C) with low (~0.24 J g-1) enthalpy. 相似文献
12.
N. Wiegand L. Vámhidy B. Patczai E. Dömse P. Than L. Kereskai D. Lőrinczy 《Journal of Thermal Analysis and Calorimetry》2009,95(3):797-800
The Dupuytren contracture - degenerative shortening of the palmar aponeurosis - is a common disease of the hand in Europe.
The aetiology of the degenerative changes in the collagen structures is still not clear. To describe the clinical manifestation
of the disease we use an international classification according to Iselin. Our hypothesis was that in Dupuytren disease there
is a clear pathological abnormality in the tissue elements building up the palmar aponeurosis, which is responsible for the
disease, and could be monitored besides the classical histological methods by differential scanning calorimetry.
The thermal denaturation of different parts of human samples was monitored by a SETARAM Micro DSC-II calorimeter. All the
experiments were performed between 0 and 100°C. The heating rate was 0.3 K min−1. DSC scans clearly demonstrated significant differences between the different types and conditions of samples (control: T
m=63°C and ΔH
cal=4.1 J g−1, stage I.: T
m= 63°C and ΔH
cal=5.1 J g−1, stage II.: T
m=64°C and ΔH
cal=5.2 J g−1, stage III.: T
m=60°C and ΔH
cal=5.2 J g−1, stage IV.: T
m=60.2°C and ΔH
cal=5.3 J g−1). The heat capacity change between native and denatured states of aponeurosis samples increased with the degree of structural
alterations indicating significant water loosing. These observations could be explained with the structural alterations caused
by the biochemical processes.
With our investigations we could demonstrate that DSC is a useful and well applicable method for the investigation of collagen
tissue of the human aponeurosis. Our results may be of clinical relevance in the future i.e. in the choice of the optimal
time of surgical therapy of different clinical level Dupuytren contractures. 相似文献
13.
S. N. Solov’ev A. A. Korunov K. G. Zubkov A. A. Firer 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2012,86(3):516-518
The change in enthalpy in reactions of NiF3(s) with water and aqueous solution of potassium hydroxide are measured in the isothermal calorimetry mode at 298.15 K. The
standard enthalpy of formation Δf
H° of nickel trifluoride was found to be −816 ± 6 kJ/mol. 相似文献
14.
J. N. Zhang Z. C. Tan Q. F. Meng Q. Shi B. Tong S. X. Wang 《Journal of Thermal Analysis and Calorimetry》2009,95(2):461-467
The heat capacities (C
p,m) of 2-amino-5-methylpyridine (AMP) were measured by a precision automated adiabatic calorimeter over the temperature range
from 80 to 398 K. A solid-liquid phase transition was found in the range from 336 to 351 K with the peak heat capacity at
350.426 K. The melting temperature (T
m), the molar enthalpy (Δfus
H
m0), and the molar entropy (Δfus
S
m0) of fusion were determined to be 350.431±0.018 K, 18.108 kJ mol−1 and 51.676 J K−1 mol−1, respectively. The mole fraction purity of the sample used was determined to be 0.99734 through the Van’t Hoff equation.
The thermodynamic functions (H
T-H
298.15 and S
T-S
298.15) were calculated. The molar energy of combustion and the standard molar enthalpy of combustion were determined, ΔU
c(C6H8N2,cr)= −3500.15±1.51 kJ mol−1 and Δc
H
m0 (C6H8N2,cr)= −3502.64±1.51 kJ mol−1, by means of a precision oxygen-bomb combustion calorimeter at T=298.15 K. The standard molar enthalpy of formation of the crystalline compound was derived, Δr
H
m0 (C6H8N2,cr)= −1.74±0.57 kJ mol−1. 相似文献
15.
S. P. Chen X. X. Meng Q. Shuai B. J. Jiao S. L. Gao Q. Z. Shi 《Journal of Thermal Analysis and Calorimetry》2006,86(3):767-774
A
solid complex Eu(C5H8NS2)3(C12H8N2) has been obtained from reaction of
hydrous europium chloride with ammonium pyrrolidinedithiocarbamate (APDC)
and 1,10-phenanthroline (o-phen⋅H2O)
in absolute ethanol. IR spectrum of the complex indicated that Eu3+
in the complex coordinated with sulfur atoms from the APDC and nitrogen atoms
from the o-phen. TG-DTG investigation provided
the evidence that the title complex was decomposed into EuS.
The
enthalpy change of the reaction of formation of the complex in ethanol, Δr
H
m
θ(l), as –22.214±0.081 kJ mol–1,
and the molar heat capacity of the complex, c
m,
as 61.676±0.651 J mol–1 K–1,
at 298.15 K were determined by an RD-496 III type microcalorimeter. The enthalpy
change of the reaction of formation of the complex in solid, Δr
H
m
θ(s), was calculated as 54.527±0.314 kJ mol–1
through a thermochemistry cycle. Based on the thermodynamics and kinetics
on the reaction of formation of the complex in ethanol at different temperatures,
fundamental parameters, including the activation enthalpy (ΔH
≠
θ),
the activation entropy (ΔS
≠
θ),
the activation free energy (ΔG
≠
θ),
the apparent reaction rate constant (k),
the apparent activation energy (E), the
pre-exponential constant (A) and the reaction
order (n), were obtained. The constant-volume
combustion energy of the complex, Δc
U,
was determined as –16937.88±9.79 kJ mol–1
by an RBC-II type rotating-bomb calorimeter at 298.15 K. Its standard enthalpy
of combustion, Δc
H
m
θ,
and standard enthalpy of formation, Δf
H
m
θ,
were calculated to be –16953.37±9.79 and –1708.23±10.69
kJ mol–1, respectively. 相似文献
16.
Digo Hermínio P. Pinto Susana S. Moura Ramos Joaquim J. 《Journal of Thermal Analysis and Calorimetry》2004,77(3):893-904
The thermal behaviour of salicylsalicylic acid (CAS number 552-94-3) was studied by differential scanning calorimetry (DSC).
The endothermic melting peak and the fingerprint of the glass transition were characterised at a heating rate of 10°C min-1. The melting peak showed an onset at T
on = 144°C (417 K) and a maximum intensity at T
max = 152°C (425 K), while the onset of the glass transition signal was at T
on = 6°C. The melting enthalpy was found to be ΔmH = 28.9±0.3 kJ mol-1, and the heat capacity jump at the glass transition was ΔC
P = 108.1±0.1 J K-1mol-1. The study of the influence of the heating rate on the temperature location of the glass transition signal by DSC, allowed
the determination of the activation energy at the glass transition temperature (245 kJ mol-1), and the calculation of the fragility index of salicyl salicylate (m = 45). Finally, the standard molar enthalpy of formation of crystalline monoclinic salicylsalicylic acid at T = 298.15 K, was determined as ΔfHm
o(C14H10O5, cr) = - (837.6±3.3) kJ mol-1, by combustion calorimetry.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
17.
Gholam Hossein Rounaghi Massoumeh Mohajeri Shima Ashrafi Hoda Ghasemi Saman Sedaghat Maryam Tavakoli 《Journal of inclusion phenomena and macrocyclic chemistry》2007,58(1-2):1-6
Conductance measurements are reported for nickel(II), cupper(II), silver(I) and cadmium(II), salts in acetonitrile (AN)–dimethylformamide
(DMF) binary solvents containing macrocyclic ligand, 1,10-dibenzyl-1,10-diaza-18-crown-6 (DBDA18C6) at different temperatures.
The changes in molar conductance caused by addition of DBDA18C6 to solutions were analyzed by non-linear least squares to
give stability constants of 1:1 metal cation–DBDA18C6 complexes. The results show that the stabilities of the complexes are
sensitive to solvent composition and in some cases the sequence of stabilities is changed with changing the composition of
the mixed solvents. The values of thermodynamic quantities (ΔH°c and ΔS°c) for formation of DBDA18C6-Ni2+, DBDA18C6-Cu2+, DBDA18C6-Ag+ and DBDA18C6-Cd2+ complexes were obtained from temperature dependence of the stability constants and the results show that the values of ΔH°c and ΔS°c for these complexes are sensitive to the nature and composition of AN–DMF binary solutions, but they do not vary monotonically
with the solvent composition. 相似文献
18.
G.H. Rounaghi G.N. Gerey M.S. Kazemi 《Journal of inclusion phenomena and macrocyclic chemistry》2006,55(1-2):167-172
The complex formation between Cu2+, Zn2+, Tl+ and Cd2+ metal cations with macrocyclic ligand, dibenzo- 18-crown-6 (DB18C6) was studied in dimethylsulfoxide (DMSO)–ethylacetate (EtOAc) binary systems at different temperatures using conductometric method. In all cases, DB18C6 forms 1:1 complexes with these metal cations. The stability constants of the complexes were obtained from fitting of molar conductivity curves using a computer program, Genplot. The non-linear behaviour which was observed for variations of log K
f of the complexes versus the composition of the mixed solvent was discussed in terms of changing the chemical and physical properties of the constituent solvents when they mix with one another and, therefore, changing the solvation capacities of the metal cations, crown ether molecules and even the resulting complexes with changing the mixed solvent composition. The results show that the selectivity order of DB18C6 for the metal cations in pure ethylacetate and pure dimethylsulfoxide is: Tl+ > Cu2+ > Zn2+ > Cd2+ but the selectivity order is changed with the composition of the mixed solvents. The values of enthalpy changes (ΔH°C) for complexation reactions were obtained from the slope of the van’t Hoff plots and the changes in standard enthalpy (ΔS°C) were calculated from the relationship: ΔG°C,298.15=ΔH°C − 298.15 ΔS°C. The obtained results show that in most cases, the complexes are enthalpy stabilized, but entropy destabilized and the values of ΔH°C and ΔS°C depend strongly on the nature of the medium. 相似文献
19.
Using the values of standard molar enthalpy of reaction for dimethylethyleneurea (dmeu),dimethylformamide (dmf), dimethylacetamide
(dma), tetramethylurea (tmu),hexamethylphosphoramide (hmpa) and pyridine (py) with the acids BF3, SbCl5, ZnCl2 and AsCl3, it is shown that, in terms of acid-base behaviour, ZnCl2 is closer to BF3, which differs from SbCl5. Furthermore, the equation −Δr
H
m(ZnCl2) = − [1.26⋅Δr
H
m(BF3)]−56.99 correlates with the standard molar enthalpy of reaction for the same set of molecules with ZnCl2 and BF3. A similar equation was obtained to estimate the enthalpy of reaction with AsCl3: −Δr
H
m(AsCl3) = − [4.12⋅Δr
H
m(BF3)]− 417.82. It is also shown that, for hmpa and tmu, sterical hindrance is a prominent factor that influences the coordination
chemistry of the acidic centres, whose deviation from the linearity can be considered as a measure for the steric contribution
to Δr
H
m.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
20.
Pena R. Chauvet A. Masse J. Ribet J. P. Maurel J. L. 《Journal of Thermal Analysis and Calorimetry》1998,53(3):697-709
The phase diagram of R(+)-S(-) efaroxan hydrochloride (Tfus.(R)=245.1±0.3°C. ΔHfus.(R)=119.6±3.0 J g-1) shows a racemic compound. The melting temperature and melting enthalpy of the compound are: Tfus.(RS)=247.8±0.2°C and ΔHfus. (RS)=124.6±2.4 J g-1. A solid ↔ solid transformation takes place at Ttrs.=180±1°C, ΔHtrs.=15.0±0.4 J g-1. This transition is observed between 3 and 97% R(+). The stability of the racemic compound already established in a previous
study was confirmed by the value of Petterson's coefficient (i=1.19). The two eutectic positions at 20 and 80% R(+) that define
the range over which the racemic compound is found, exclude the use of resolution methods by preferential crystallization.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献