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1.
Excess thermodynamic properties of benzene + p-xylene have been obtained at 288.15, 298.15, and 313.15 K. VE was obtained with a Sodev vibrating-tube densimeter, HE with a Picker flow microcalorimeter, and GE was calculated from solid + liquid phase equilibria measurements. Measurements were also made of the heat capacity of liquid p-xylene as a function of temperature using the heat-capacity unit of the Picker flow microcalorimeter.  相似文献   

2.
Excess volumes VE for trichloroethene (CCl2CHCl) + benzene, + toluene, + p-xylene, + tetrachloromethane, and + trichloromethane have been measured at 303.15 K, by direct dilatometry. VE has been found to be positive for trichloroethene + benzene, and + trichloromethane, and negative for trichloroethene + toluene, and + p-xylene. For trichloroethene + tetrachloromethane VE is positive at low mole fractions of C2HCl3 and negative at high mole fractions.  相似文献   

3.
The densities (ρ), ultrasonic speeds (ν), and refractive indices (n) of binary mixtures of styrene (STY) with m-, o-, or p-xylene, including those of their pure liquids, were measured over the entire composition range at the temperatures 298.15, 303.15, 308.15, and 313.15 K. The excess volumes (VE), deviations in isentropic compressibilities (Δks), acoustic impedances (ΔZ), and refractive indices (Δn) were calculated from the experimental data. Partial molar volumes (V0?,2) and partial molar isentropic compressibilities (K0?,2) of xylenes in styrene have also been calculated. The derived functions, namely, VE, Δks, ΔZ, Δn, V0?,2, and K0?,2 were used to have a better understanding of the intermolecular interactions occurring between the component molecules of the present liquid mixtures. The variations of these parameters suggest that the interactions between styrene and o-, m-, or p-xylene molecules follow the sequences: p-xylene>o-xylene>m-xylene. Apart from using density data for the calculation of VE, excess molar volumes were also estimated using refractive index data. Furthermore, several refractive index mixing rules have been used to estimate the refractive indices of the studied liquid mixtures theoretically. Overall, the computed and measured data were interpreted in terms of interactions between the mixing components.  相似文献   

4.
A semi-continuous dilatometer for measuring excess volume is described. Excess volumes of p-xylene +n-hexane + n-octane, +n-decane, +n-dodecane, +n-tetradecane, and +n-hexadecane have been measured at 298.15 K as a function of composition.  相似文献   

5.
《Fluid Phase Equilibria》1999,155(2):261-276
The excess isentropic compressibilities, KsE for seven binary mixtures of methyl methacrylate+benzene, +o-xylene, +m-xylene, +p-xylene, +toluene, +ethylbenzene and +cyclohexane were estimated from the measured densities and speeds of sound at 298.15 and 308.15 K. The KsE values were large and positive for MMA+cyclohexane and +m-xylene, while they were negative for other mixtures. A qualitative analysis of KsE values was made in terms of molecular interactions. The speeds of sound of all the mixtures were also predicted from the free length theory (FLT) and collision factor theory (CFT).  相似文献   

6.
The viscosities of the mixtures of 1,2-dibromoethane + cyclohexane, + benzene, +toluene, +o-xylene, +m-xylene, and +p-xylene have been measured at 298.15 and 308.15 K as a function of composition. The viscosity data have been analysed in the light of approaches developed by Hind and Grunberg . Using Eyring kine- matic scheme the viscosity data have been employed to calculate activation energies of flow.  相似文献   

7.
Experimental data on density, viscosity, and refractive index at T = (298.15, 303.15, and 308.15) K, while speed of sound values at T = 298.15 K are presented for the binary mixtures of (methylcyclohexane + benzene), methylbenzene (toluene), 1,4-dimethylbenzene (p-xylene), 1,3,5-trimethylbenzene (mesitylene), and methoxybenzene (anisole). From these data of density, viscosity, and refractive index, the excess molar volume, the deviations in viscosity, molar refraction, speed of sound, and isentropic compressibility have been calculated. The computed values have been fitted to Redlich-Kister polynomial equation to derive the coefficients and estimate the standard errors. Variations in the calculated excess quantities for these mixtures have been studied in terms of molecular interactions between the component liquids and the effects of methyl and methoxy group substitution on benzene ring.  相似文献   

8.
Optical absorption spectra obtained in cyclohexane solutions of benzene, toluene, and p-xylene contain bands at 620 to 640 nm, assigned to Sn← S1 monomer transitions. With concentrated solutions, excimer absorption spectra nave been found. With the two polymers, absorption of (intramolecular) excimers has been detected only.  相似文献   

9.
Multiphoton ionization (MPI) fragmentation pattern of p-xylene is investigated as a function of laser power at 193 and 248 nm. The mass pattern at 193 nm suggests the presence of two reaction sequences and the occurrence of drastic rearrangement in the parent ion and also in the superexcited xylene before fragmentation.  相似文献   

10.
Abstract

Density and viscosity measurements on the binary mixtures of methanol+p-xylene, n-propanol+p-xylene and n-butanol+p-xylene at 303.15, 313.15 and 323.15K are reported The representation of the data by common mixing rules is also studied.  相似文献   

11.
Excess enthalpies of bromoform + toluene, +o-xylene +m-xylene and +p-xylene have been determined at 308.15 K. These compounds have been examined for Barker's theory in order to understand the magnitude and nature of various interactions between the components of these mixtures. It has been concluded that the H-atom and one bromine atom of bromoform interact with the π cloud of the aromatic ring. These conclusions have been supplemented by n.m.r. studies. An approximate distance of the bromoform proton from the plane of the aromatic ring has also been calculated and examined in the light of the proposed geometry of the molecular complexes. Equilibrium constants for the complexations reaction have also been determined.  相似文献   

12.
Abstract

The gas chromatographic method proposed by us for simple and accurate measurement of isothermal phase equilibria has been applied to the binary mixtures formed by alkylbenzenes amongst themselves. Results on the binary mixtures of: benzene - toluene, toluene + o-xylene, toluene + p-xylene, toluene + ethylbenzene, ethylbenzene + o-xylene and ethylbenzene + p-xylene are presented in this paper. The present measurements on benzene + toluene system at 40°C are in good agreement with the isothermal phase equilibrium data available in the literature.  相似文献   

13.
The use of the ligand bis(di-tert-butylphosphino)-o-xylene (dtbpx) in palladium-catalysed carbonylative and Suzuki-Miyaura cross-coupling reactions is described. Aryl and vinyl halides readily entered into the carbonylative catalytic cycle affording carboxylic acids, amides as well as primary, secondary and tertiary esters, respectively, in good yields. Aryl iodides, bromides and chlorides gave high yields of biphenyl products upon reaction with both activated and unactivated boronic acids.  相似文献   

14.
The experimental isothermal Pxy data between 263.15 and 343.15 K at 10 K intervals of liquid binary mixtures 2,2′-oxybis[propane] (diisopropylether or DIPE) + toluene, +m-xylene and of the three pure components are reported. Data reduction by Barker's method provides correlation for excess molar Gibbs energy (GE).  相似文献   

15.
The three (η6-xylene)Mo(CO)3 complexes have been prepared and crystallographically characterized to determine the rotational relationship of the arene ring to the undercarriage, as has been suggested by theoretical studies. In fact, no such relationship can be seen, especially when combined with eight examples of structures with Z′ > 1, where both staggered and eclipsed forms are found.  相似文献   

16.
Molar excess volumes Ve and molar excess enthalpies He of binary methylenebromide (i) +benzene. +toluene, and + o?, + m? and + p-xylene (j) mixtures have been determined at 298.15 and 308.15 K. The data have been analysed in terms of recent approaches for solutions of nonelectrolytes, and the results suggest that these mixtures are characterised by specific interactions between the components. Self-volume interaction coefficients ViiVjj have also been evaluated.  相似文献   

17.
Molar excess volumes VEijk of methylenebromide i + pyridine j + β-picoline (k, cyclohexane (i) + pyridine (j) + β-picoline(K), benzene(i)+toluene(j)+1,2-dichloroethane(k), benzene(i) + 0-xylene(j) + 1,2-dichloroethane(k) and benzene(i) + p-xylene(j) + 1,2-dichloroethane(k) mixtures have been determined dilatometrically at 298.15 K. The data have been examined in terms of Sanchez and Lacombe theory and the graph-theoretical approach, and it is found that they are described well by the latter. Self- and cross-volume interaction coefficients Vjk, Vjjk and Vjkk, etc., have also been evaluated and the values utilised to study molecular interactions between the jth and kth molecular species in the presence of the ith in these i + j + k mixtures.  相似文献   

18.
Summary This paper reports excess molar enthalpies of the binary systems hexane+ethyl benzene, hexane+o-xylene, hexane+m-xylene and hexane+p-xylene at 298.15 K and atmospheric pressure, over the whole composition range. The data was measured directly using a Calvet microcalorimeter. The excess magnitude was correlated to a Redlich-Kister type equation for each mixture. Also, we will discuss the results for the four mixtures studied here and by comparison with the same binary systems but containing propyl propanoate as first component. Finally, we will correlate our results with the Nitta-Chao and the three UNIFAC theoretical approximations.  相似文献   

19.
Excess volumes of mixing, VE, for binary mixtures of 1,2-dichloroethane with benzene, toluene, o?, m?, and p-xylenes have been determined at 308.15 K over the complete composition range. VE is positive for all these mixtures and varies in the order m-xylene >o-xylene >p-xylene > benzene > toluene. The experimental data have been analyzed in terms of the Prigogine's average potential cell model coupled with Balescu's theory. The calculated VE values do not agree with the corresponding experimental values.  相似文献   

20.
This paper reports experimental densities and refractive indices of (cyclohexane, or n -heptane  + o -xylene, or m -xylene, or p -xylene, or ethylbenzene) over the whole composition range at T =  298.15 K and at atmospheric pressure. Excess molar volumes and changes of refractive indices were calculated from the experimental data obtained. Partial excess molar volumes were also computed for all the mixtures studied. The results were fitted by means of the Redlich–Kister equation with the aid of F -test to optimize the number of parameters. Measurements were compared with other literature values. Different empirical and semiempirical models were applied in order to estimate physical property values and good agreement was obtained with experimental results.  相似文献   

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