Experimental results for the solubility of tetrafluoromethane (CF4, R14) in the ionic liquid 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide ([hmim][Tf2N]) are presented for temperatures between 293.3 and 413.3 K, at pressures (gas molalities) up to 9.6 MPa (0.22 mol kg-1). The experimental results were determined with a high-pressure view-cell technique operating on the synthetic method. The experimental data were used to determine Henry's constant of tetrafluoromethane in [hmim][Tf2N]. The results for the Henry's constant (at zero pressure) are correlated (on the molality scale) within the experimental uncertainty (i.e., about 1.1%) by ln(k(0)(H,CF4)/MPa) = 7.537 - 893.8/(T/K) - 0.003977(T/K). Henry's law was also extended to describe the gas solubility at higher pressures. Furthermore, a cubic equation of state was used to correlate the gas solubility over the entire range of experimentally investigated temperature and pressure. Both methods proved suited for a reliable correlation of the new experimental data. 相似文献
We present a rare example of a decay mechanism playing a constructive role in quantum information processing. We show how
the state of an atom trapped in a cavity can be teleported to a second atom trapped in a distant cavity by the joint detection
of photon leakage from the cavities. The scheme, which is probabilistic, requires only a single three level atom in a cavity.
We also show how this scheme can be modified to a teleportation with insurance. 相似文献
A rival to native peroxidase! An existing binding site for glutathione was combined with the catalytic residue tellurocysteine by using an auxotrophic expression system to create an engineered enzyme that functions as a glutathione peroxidase from the scaffold of a glutathione transferase (see picture). The catalytic activity of the telluroenzyme in the reduction of hydroperoxides by glutathione is comparable to that of native glutathione peroxidase.
In this article, we investigate vapor-liquid-liquid equilibria (VLLE) of binary systems using a simple volumetric method. Being different from the usual cloud-point method for the determination of liquid-liquid separation boundaries, the present volumetric method is able to determine the direct VLLE properties, such as equilibrium compositions, as well as molar volumes of the two liquid phases, by measuring only weights and volumes of liquid samples. The theory behind this method is described, and detailed error analyses for our simple apparatus are discussed by using well-established systems in the literature: water + 2-butanol and 1-butanol + 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim][PF(6)]). Then, results for mixtures of [bmim][PF(6)] and pentafluoroethane (R-125) are provided, as well as those of the test systems above. As predicted in our earlier work, this binary system shows liquid-liquid separations in the R-125-rich side solutions with a lower critical solution temperature. In addition, we have found very large negative excess molar volumes in this system. 相似文献
Sorption isotherms for trifluoromethane (R-23) in activated carbon have been measured at ca. 298 and 323 K using a gravimetric microbalance. High-resolution TEM images of the activated carbon show a very uniform microstructure with no evidence of any contaminants. The adsorption in the activated carbon reaches about 22.8 mol kg?1 at 2.0 MPa and 298 K or 17.6 mol kg?1 at 2.0 MPa and 323 K. Three different adsorption models (Langmuir, multi-site Langmuir, and BET equations) have been used to analyze the activated carbon sorption data, with a particular interest in the heat of adsorption (?ΔH). The heat of adsorption for R-23 in the activated carbon was about 29.78 ± 0.04 kJ mol?1 based on the multi-site Langmuir model and is within the range of typical physical adsorption. According to the IUPAC classification, the activated carbon exhibits Type I adsorption behavior and was completely reversible. Compared with our previous work for the sorption of R-23 in zeolites (5A (Ca,Na-A), 13X (Na-X), Na,K-LSX, Na-Y, K,H-Y, Rb,Na-Y) and ionic liquids ([omim][TFES] and [emim][Tf2N]) the activated carbon had the highest adsorption capacity. The adsorption process in the activated carbon also took less time than in the zeolites or the ionic liquids to reach thermodynamic equilibrium. 相似文献