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, 11 ], transesterification of glycerol with cyclic carbonates such as ethylene carbonate [ 10 , 12 ], and transesterification of glycerol with alkyl carbonates such as dimethyl carbonate [ 6 , 13 – 15 ] or diethyl carbonate [ 16 ]. Among these

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Abstract  

In order to study the dependence of non-universal critical quantities on the molecular structure, heat capacities per unit volume for the dimethyl carbonate+(heptane, octane, nonane, decane or tridecane) critical mixtures near their upper consolute point are measured. The data are obtained at atmospheric pressure as a function of temperature in the homogeneous and heterogeneous regions by means of a differential scanning calorimeter. The exponent and amplitudes that characterises the observed critical anomaly are determined from experimental data, being their values coherent to previous results; in addition, the critical amplitudes of the correlation length was calculated from critical amplitudes using the universality of the two-scale factor. The influence of the alkane length on the critical temperature and heat capacity critical amplitude are analysed.

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Abstract  

Densities for dimethyl carbonate + p-xylene + n-decane ternary system, at 288.15 and 298.15 K and at atmospheric pressure, were measured. The corresponding excess molar volumes were calculated from the experimental data and were fitted by means of Cibulka equation.

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superior to alternatives, such as ethanol, dimethyl carbonate (DMC) or diethyl carbonate (DEC). In comparison with DMC and DEC, DPC has larger molecular weight, higher flash point, stronger anti-volatile and higher energy content, so DPC is more stable and

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This paper describes the next stage in our development of self-optimising reactors. We demonstrate that the same reaction can be optimised for a series of different criteria including yield, space–time yield, E factor and a weighted yield function (the product of space–time yield and yield). In different experiments, we achieved 97.6% yield, space–time yield of 42.9 kg/L/h and E factors of 1.4 and 3.3 (including CO2) and the weighted yield, which gave a promising balance between yield, E factor and space–time yield.

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The reaction of urea with ZnO was investigated by FTIR and TPD. It was found that urea was thermally decomposed into isocyanic acid on ZnO, and the adsorbed isocyanic acid reacted with ZnO to form zinc isocyanate. Catalytic evaluation showed that ZnO had high activity towards urea methanolysis in a batch reactor, and zinc element and isocyanate were all detected in the product solution. Furthermore, the soluble zinc content was proportional to the DMC yield. Sample analyses suggested that the soluble zinc existed in the form of Zn(NCO)2(NH3)2, which originated from the reaction of ZnO with urea. It was the complex (not ZnO) that catalyzed the urea methanolysis. Based on these observations, a possible mechanism was suggested.

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We construct with a differential scanning calorimeter (DSC) a phase diagram for the ethylene carbonate (EC)-dimethyl carbonate (DMC) binary system for its liquid-solid phase equilibria. We determine the eutectic composition of the binary system using an enthalpic method that we devised based on the composition dependence of the enthalpy of solidus melting, with highly consistent results. We also discuss the merits and limitations of this enthalpic method.

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The thermal behaviors of four organic solvents with/without LiPF6 were measured by C80 microcalorimeter at a 0.2�C min−1 heating rate. With the addition of 1 M LiPF6, the ethylene carbonate (EC) and propylene carbonate (PC) show the exothermic peaks at elevated temperature, which lessen their stabilities. The exothermic peak temperatures of EC and PC based LiPF6 solutions are at 212 and 223�C, respectively, in argon filled vessel. However, two endothermic peak temperatures were detected in diethyl carbonate (DEC) based LiPF6 solution at 182 and 252.5�C, respectively, in argon filled vessel. Dimethyl carbonate (DMC) based LiPF6 solution shows two endothermic peak temperatures at 68.5 and 187�C in argon filled vessel at elevated temperature. Consequently, it is concluded that LiPF6 play a key role in the thermal behavior of its organic solution.

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, Thiébaud , S , Borredon , E , Gars , PL 2003 High performance method for O- methylation of phenol with dimethyl carbonate . Appl Catal A Gen 241 : 227 – 233 10.1016/S0926-860X(02)00467-2 . 2

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-Khand reactions in a photochemical flow microreactor” K. Asano , Y. Uesugi , J.-i. Yoshida * Organic Letters 2013 , 15 , 2398 – 2401 . “Highly selective phosgene-free carbamoylation of aniline by dimethyl carbonate under continuous

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