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Jia L.-N.,Northwest University, China | Zhao Y.,Zhejiang Quhua Fluorine Chemistry Co. | Hou L.,Northwest University, China | Cui L.,Northwest University, China | And 2 more authors.
Journal of Solid State Chemistry | Year: 2014

A new three-dimensional porous framework [Co2(bpdc) 2(H2bpz)]â̂™2(DMF)·5(H 2O) (1) (H2bpdc=4,4′-biphenyldicarboxylic acid, H2bpz=3,3′,5,5′-tetramethyl-4,4′-bipyrazole) has been solvothermally synthesized by employing mixed H2bpdc and H 2bpz ligands. 1 is a pillared-layer framework based on a binuclear paddle-wheel Co2(O2C-R)4 cluster, and exhibits a 2-fold interpenetrated 6-connected pcu topology. H2bpz bridges Co2(O2C-R)4 clusters with an angular coordination configuration to form interesting left- and right-handed helical chains. 1 possesses a two-dimensional porous system decorated by uncoordinated pyrazole -NH groups of H2bpz, leading to high adsorption selectivities for CO2 over N2 and H2. In addition, the strong antiferromagnetic interactions between the Co2+ ions in cluster were observed. © 2013 Elsevier Inc.

Gao N.,Zhejiang University | Chen G.,Zhejiang University | Li R.,Zhejiang University | Wang Y.,Zhejiang University | And 2 more authors.
Journal of Thermal Analysis and Calorimetry | Year: 2015

Isobaric heat capacity of pressurized liquid trans-1,3,3,3-tetrafluoropropene [R1234ze(E)] was measured by scanning calorimetry. The experimental system basically consists of a Calvet calorimeter (Setaram C80) and a pressure balance unit. A total of 95 data points were obtained at temperatures from 310.15 to 365.15 K and pressures up to 5.5 MPa. An empirical equation was used to correlate the experimental data with an average absolute percentage deviation of 0.18 %. Besides, a comparison was carried out between present data and literature data and three latest fundamental equations of state. Finally, saturated liquid heat capacity of R1234ze(E) was also investigated in this paper. © 2015 Akadémiai Kiadó, Budapest, Hungary

Chen Q.,Zhejiang University | Yan J.,Zhejiang University | Chen G.,Zhejiang University | Zhao Y.,Zhejiang Quhua Fluorine Chemistry Co. | And 3 more authors.
Journal of Fluorine Chemistry | Year: 2015

Abstract According to the standard of American Society for Testing Materials, an experimental apparatus for testing flammability of flammable refrigerants was developed. Its reliability was validated subsequently. Studies on dimethyl ether have been performed since it's considered as one of the most alternative substitute for R134a. No experimental or theoretical study has been conducted on the flammability of the binary mixture DME/R134a so far. In this paper, the flammability data of the binary mixture DME/R134a with different volume ratios were tested, the corresponding explosion limits and critical flammability ratio were also obtained. The results show that when the volume ratio of the flame retardant R134a to the flammable refrigerant DME is about 5, the binary mixture reaches its critical flammability ratio. R1234yf is a new and promising alternative, its ternary mixture DME/R1234yf/R134a shows promise as a new air-conditioning refrigerant, a explosion limit was tested and the critical suppressive line of the ternary mixture DME/R1234yf/R134a was presented. The flammability data is of great importance in manufacture and application of the new flammable refrigerants. © 2015 Elsevier B.V.

Fang L.,Zhejiang University | Gao Z.,Zhejiang University | Wang X.,Zhejiang Quhua Fluorine Chemistry Co. | Lei J.,Zhejiang Quhua Fluorine Chemistry Co. | And 2 more authors.
Journal of Chemical and Engineering Data | Year: 2014

The vapor-liquid equilibrium (VLE) data of different mass fractions of the mixture (ethyl fluoride (HFC-161) + alkylbenzene (AB) lubricant oil) at a temperature range from (278.15 to 348.15) K were measured by single-phase cycle method, and the solubility and miscibility for the mixture (HFC-161 + AB lubricant oil) were analyzed in this paper. The experimental results showed that there was no stratification, no sediment generation, and no color change during the whole experiment for the mixture (HFC-161 + AB lubricant oil). The vapor pressure decreased with the increase of oil concentration. The experimental results were correlated by the nonrandom two-liquid (NRTL) equation. The parameters of the NRTL equation were regressed. From the correlated results, the average relative pressure deviation was 1.4 %, and the maximum relative pressure deviation was 4.2 %. Meanwhile, the results were compared with those of the HFC-161 + polyol ester (POE) lubricant oil mixture in the temperature range of (278.15 to 328.15) K. For a given HFC-161 mass fraction and temperature, HFC-161 is more soluble in POE lubricant oil than in AB lubricant oil. In this work, AB lubricant oil may be a better choice for HFC-161 than POE lubricant oil to some extent. © 2014 American Chemical Society.

Han X.,Zhejiang University | Gao Z.,Zhejiang University | Lei J.,Zhejiang Quhua Fluorine Chemistry Co. | Yang B.,Zhejiang Quhua Fluorine Chemistry Co. | And 2 more authors.
Journal of Chemical and Engineering Data | Year: 2015

Isothermal vapor-liquid equilibrium (VLE) data for the ternary mixture of 1,1,1,2-tetrafluoroethane (HFC-134a) + 2,3,3,3-tetrafluoroprop-1-ene (HFO-1234yf) + dimethyl ether (DME) were measured at temperatures from 253.15 K to 323.15 K using a recirculation apparatus. The experimental data were correlated by the PR (Peng-Robinson) equation of state with the LCVM (linear combination of Vidal and Michelsen) mixing rule and the NRTL (nonrandom two liquid) model. The average absolute vapor composition deviations are 0.007 (for HFC-134a) and 0.012 (for HFO-1234yf), and the largest absolute deviation of the vapor compositions are 0.022 (for HFC-134a) and 0.031 (for HFO-1234yf); the average relative pressure deviation is within 1.2 % and its largest relative pressure deviation is 3.7 %. The correlation results are in good agreement with the experiment results. With the regressed parameters obtained by the ternary mixture (HFC-134a + HFO-1234yf + DME), the VLE of two binary mixtures (HFC-134a + HFO-1234yf and HFC-134a + DME) were predicted by the PR + LCVM + NRTL model. The predicted results were compared with the experimental data of other researchers. The results showed that the regressed parameters obtained by the ternary mixture (HFC-134a + HFO-1234yf + DME) in this work could be used to predict VLE behavior of the binary mixtures. The results also indicated that there is no azeotrope in the ternary mixture. © 2015 American Chemical Society.

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