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1.
《Fluid Phase Equilibria》1999,154(2):261-284
Comprehensive phase diagrams of methanol/CHF3 and methanol/H2O/CHF3 mixtures over the temperature range of 25–100°C and pressure range of atmospheric to 340 atm are reported. Fluoroform is expected to be useful as an alternative to CO2 for enhancing the fluidity of liquid mixtures due to its high polarity and low viscosity. Therefore, these mixtures will be studied as mobile phases for enhanced-fluidity liquid chromatography and extraction. The phase behavior of methanol/CHF3 and methanol/H2O/CHF3 was compared to that of methanol/CO2 and methanol/H2O/CHF3. Fluoroform is markedly more miscible with methanol or methanol/H2O than is CO2. Data for methanol/CHF3 binary mixtures were also modeled by the Peng–Robinson equation of state. The correlation results showed that the PR equation of state with two temperature-independent binary parameters was capable of representing the experimental data over the entire temperature range with an average relative deviation within 6%. 相似文献
2.
《Fluid Phase Equilibria》1997,135(2):259-268
The solubilities of isobutane at pressures from 40 to 102 kPa and a temperature of 298.15 K are presented for three mixed solvent solutions: methanol + benzene, methanol + cyclohexane, and benzene + cyclohexane. 相似文献
3.
Esra Korkmaz Nilgun Ozpozan Kalaycioglu 《Journal of Thermal Analysis and Calorimetry》2012,110(3):1113-1118
Using tetra-n-butyl titanate and magnesium nitrate as raw materials, Dy3+ and Pr3+ ions in the matrix of magnesium titanate (MgTiO3) was successfully synthesized by a modified solid-state reaction. The mixtures to achieve a solid-state reaction were heated in porcelain crucibles at 600?°C for 2?h, 900?°C for 6?h, and 1000.0?°C for 2?h. The reaction products obtained in an air atmosphere were characterized by X-ray powder diffractions. The optimization of reaction conditions were carried out by thermal gravimetry and differential thermal analysis methods. Surface and elemental analyses were performed by using on SEM instrument. The excitation and emission spectra were recorded by photoluminescence spectrophotometer. 相似文献
4.
Methanol is a promising fuel for power devices such as fuel cells because it has a high theoretical capacity per volume and weight, is relatively easy to handle and is easy to store. Many studies on the alkaline methanol fuel cell system were made in the 1960s and 1970s. The article gives a brief summary of these studies and shows some results of the new work started recently at the TU Graz, AustriaDedicated to Prof. Wolf Vielstich on the occasion of his 80th birthday in recogniton of his numerous contributions to interfacial electrochemistry. 相似文献
5.
Mónica B. Gramajo Jonatan H. Veliz Alicia M. Cases 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2017,91(3):529-535
The phase equilibrium data for methanol + ethanol + isooctane systems were obtained at 303.15 K. Data for methanol + ethylbenzene + isooctane system were taken from literature. The effect of ethanol addition on the system equilibrium was investigated at the same temperature. The distribution curves for ternary and quaternary system was analyzed. The experimental results for ternary systems were correlated with UNIQUAC and NRTL equations. For the ternary systems studied here, the NRTL equation is more accurate than the UNIQUAC. The equilibrium data for the three ternary systems were used to determine interactions parameters for the UNIQUAC equation. For the quaternary system, the experimental data can be fitted more accurately to UNIQUAC equation than by the UNIFAC method. 相似文献
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8.
《Fluid Phase Equilibria》2004,224(1):31-37
Liquid–liquid equilibrium (LLE) data for three binary alcohol + n-alkane (C10–C16) systems—methanol + decane, ethanol + tetradecane, and ethanol + hexadecane—were measured using a laser scattering technique. The experimentally determined cloud points were satisfactorily correlated by three local composition models (NRTL, Tsuboka–Katayama’s modification of the Wilson equation, and the modified complete local composition model suggested by Nagata and Tamura). Prediction of vapor–liquid equilibria by means of these models with parameters obtained from the LLE data was also tested. 相似文献
9.
Saifutdinov B. R. Davankov V. A. Il’in M. M. 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2017,91(3):577-580
Russian Journal of Physical Chemistry A - The thermodynamic characteristics of the adsorption of several 1,3,4-oxadiazoles and 1,2,4,5- tetrazines from methanol and water-methanol solutions onto... 相似文献
10.
Results of studying the spectral and luminescent properties of Eu3+ ions upon homogeneous excitation of POCl3–SnCl4–-UO2+
2–Eu3+ and D2O–235UO2+
2–Eu3+ solutions by -particles are presented. It was found that the radioluminescence intensity of Eu3+ ions in both solvents increases proportionally to the energy input by -particles. The yield of radioluminescence photons from europium ions in the POCl3–SnCl4–UO2+
2–Eu3+ solutions is more than nine times as high as that in D2O–UO2+
2–Eu3+. The radiation-chemical yields of excited 5
D
0 states of Eu3+ ions are 0.74 ± 0.07 and 0.18 ± 0.02 ions/100 eV in POCl3–SnCl4–UO2+
2–Eu3+ and D2O–UO2+
2–Eu3+ solutions, respectively. 相似文献
11.
A. M. Castro Luna A. Bonesi W. E. Triaca V. Baglio V. Antonucci A. S. Aricò 《Journal of Solid State Electrochemistry》2008,12(5):643-649
High surface area carbon-supported Pt and bimetallic Pt–Fe catalysts are investigated for the oxygen electro-reduction reaction
(ORR) in low-temperature direct methanol fuel cells (60 °C). The electrocatalysts are prepared using a combination of colloidal
and incipient wetness methods allowing the synthesis of carbon-supported bimetallic nanoparticles with a particle size of
about 2–3 nm. These materials are studied in terms of structure, morphology and composition using X-ray diffraction, X-ray
fluorescence and transmission electron microscopy techniques. The electrocatalytic behaviour of these catalysts for ORR is
investigated by employing the rotating disc technique. An enhancement of the ORR is observed with the bimetallic Pt–Fe catalyst
in the oxygen-saturated electrolyte solution, with and without methanol.
Dedicated to Prof. Dr. Teresa Iwasita on the occasion of her 65th birthday in recognition of her numerous contributions to
interfacial electrochemistry. 相似文献
12.
Densities and heat capacities of methanol + acetonitrile mixtures were determined over the whole composition range at 5 and 25°C. Apparent and partial molar volumes and heat capacities for both components of the mixture were calculated from these data. These functions for acetonitrile run monotonously over the whole composition range of the mixture at both temperatures, while those for methanol exhibit extrema (volumes-minimum and heat capacities-maximum) at high acetonitrile content. The reasons of the observed behavior of the system are discussed. 相似文献
13.
Haili Pang Changting Huang Jinhua Chen Bo Liu Yafei Kuang Xiaohua Zhang 《Journal of Solid State Electrochemistry》2010,14(2):169-174
Polyaniline–tin dioxide (PANI-SnO2) composites were prepared by chemical polymerization method, and characterized by scanning electron microscopy, transmission
electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. Due to the good stability in diluted
acidic solution, PANI-SnO2 composites were selected as the catalyst support and second catalyst for methanol electro-oxidation. The electrocatalytic
properties of the PANI-SnO2 supported Pt catalyst (Pt/PANI-SnO2) for methanol oxidation have been investigated by cyclic voltammetry, chronoamperometry, and chronopotentiometry. Under the
same loading mass of Pt, the Pt/PANI-SnO2 catalyst shows higher electrocatalytic activity towards methanol electro-oxidation than Pt/SnO2 catalyst. 相似文献
14.
The dissolution enthalpies of NaI in the mixtures of methanol with 1,2-alkanediols (1,2-propanediol, 1,2-butanediol, 1,2-pentanediol) and with ??,??-alkanediols (1,3-propanediol, 1,4-butanediol, 1,5-pentanediol), as well NaI in the mixtures of water with 1,3-propanediol and 1,2-pentanediol, were determined at 298.15?K. The energetic effect of interactions between the investigated alkanediols and NaI in methanol and in water was calculated using the enthalpic pair interaction coefficients (h xy ) model. These results along with the other data concerning the NaI?Cnon-electrolyte pairs taken from our earlier reports and from the literature were analyzed with respect to the effect of the non-electrolyte properties on the variations of the h xy values. The group contributions illustrating the interactions of NaI with selected functional groups in non-electrolyte (alkanediol and alkanol) molecules, namely: CH2 and OH groups were calculated and discussed. 相似文献
15.
The stability constants, β1, of the monochloride complex of Sm(III) have been determined in mixed system of methanol and water at 1.00 mol dm−3 ionic strength using a solvent extraction technique. The values of β1 increase with an increase in the mole fraction of methanol (X
s
) in the mixed solvent system when 0≤X
s
≤0.351. The interionic distance of Sm3+−Cl− (d
Sm−Cl) in the mixed solvent system was estimated by applying the Gibb's free energy derived from β1 to a Born-type equation. It was determined that an inflection point of the variation in the estimatedd
Sm−Cl againstX
s
was present in the vicinity ofX
s
=0.054. The inflection point ofd
Sm−Cl shows a value ofX
s
between those ofd
Eu−Cl andd
Nd−Cl previously obtained by us. 相似文献
16.
《Fluid Phase Equilibria》2004,224(2):185-192
Liquid–liquid equilibrium (LLE) data for butyl tert-butyl ether + (methanol or ethanol) + water were measured experimentally at 298.15, 308.15 and 318.15 K. The experimental data were correlated with the NRTL and UNIQUAC equations. The equations were used to perform the correlation of each temperature data set and for the three temperatures data set simultaneously. The best results were found with UNIQUAC and NRTL (α = 0.1), respectively. Data prediction was carried out using the UNIFAC method, however the results found were not quantitative. 相似文献
17.
N. M. Putintsev N. V. Dolgopyatova D. N. Putintsev 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2016,90(10):2101-2103
The static permittivity and polarizability of methanol–water mixtures as functions of composition at 20°C are calculated on the basis of models proposed earlier. 相似文献
18.
Pu-jun Zeng Li-ping Yu Zhong-xian Qiu Ji-lin Zhang Chun-ying Rong Cheng-zhi Li Zai-hui Fu Shi-xun Lian 《Journal of Sol-Gel Science and Technology》2012,64(2):315-323
In this study, red phosphors Ca1?n Mg n TiO3:Eu3+,Bi3+ were prepared by the sol?Cgel method and the impact of single dopant, co-dopants and solid solutions on the photoluminescence of the samples has been also investigated. Our results show that the crystal structure of the host does not have distinct changes when doped with Eu3+, Bi3+ and/or Mg2+. The emission intensity at 615?nm of Eu3+ increased at the presence of Bi3+ ions owing to the energy transfer from Bi3+ ion to Eu3+ ion. Moreover, with the addition of Mg2+, the red emission of the phosphor was further enhanced due to the stronger absorption at 399 and 467?nm, which match well with the emission of near-UV (395?C400?nm) and blue-LED (450?C470?nm), respectively. Under the near-UV (399?nm) or blue light (467?nm) excitation, the fluorescence quantum yield of the optimal composition Ca0.9Mg0.1TiO3:0.18Eu3+,0.018Bi3+ is 0.36 and 0.41, respectively, which possesses the higher photoluminescence intensity than CaMoO4:0.2Bi3+,0.05Eu3+ and the commercially available Y2O2S:Eu3+ phosphors under near-UV excitation. Based on these results, we are currently considering the potential application of Ca0.9Mg0.1TiO3:Eu3+,Bi3+ as a near-UV or blue-chip convertible red-emitting phosphor. 相似文献
19.
Fereshteh Chekin Samira Bagheri Sharifah Bee Abd Hamid 《Journal of Solid State Electrochemistry》2014,18(4):893-898
This work reports the preparation, characterization, and electrocatalytic characteristics of a new metallic nanocatalyst. The catalyst, Pt black–graphene oxide (Pt-GO), was prepared by deposition of Pt black on the surface of graphene oxide nanosheet and characterized by transmission electron microscopy (TEM), energy-dispersive spectroscopy (EDS), and voltammetry. The Pt-graphene (Pt-GR) composite modified glassy carbon electrode (Pt-GR/GCE) was prepared with cyclic voltammetric scanning of Pt-GO/GCE in the potential range from ?1.5 to 0.2 in 0.1 M phosphate buffer solution at 50 mV·s?1 for 5 cycles. The electrocatalytic properties of the Pt-GR/GCE for methanol (CH3OH) oxidation have been investigated by cyclic voltammetry (CV); high electrocatalytic activity of the Pt-GR/GCE can be observed. This may be attributed to the high dispersion of Pt catalyst and the particular properties of GR support. The long-term stability of Pt-GR composite was investigated in 0.05 M CH3OH in 0.1 M H2SO4 solution. It can be observed that the peak current decreases gradually with the successive scans. The loss may result from the consumption of methanol during the CV scan. It also may be due to the poisoning organic compounds. The results imply that the Pt-GR composite has good potential applications in fuel cells. 相似文献
20.
High-pressure densities and P–T–x–y diagrams for carbon dioxide+linalool and carbon dioxide+limonene
《Fluid Phase Equilibria》1999,163(1):119-126
Liquid and vapor densities for carbon dioxide+linalool, and carbon dioxide+limonene were measured by using a system consisting of two vibrating tube densimeters. The P–T–x–y diagrams and saturated liquid and vapor densities for these two binary mixtures were determined at 313, 323 and 333 K, respectively, as well as at pressures up to 11 MPa. The density of the saturated CO2 phase increased with increasing pressure. At higher pressure, the density of the liquid phase decreased with increasing pressure, corresponding to an increasing amount of carbon dioxide. 相似文献