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51.
Kurnik, R.T. and Reid, R.C., 1982. Solubility of solid mixtures in supercritical fluids. Fluid Phase Equilibria, 8: 93-105Supercritical fluids are receiving widespread attention as possible extraction agents for relatively non-volatile solids and liquids. Previous studies of the solubility of solids in supercritical fluids have been limited to pure solids. These pure-component data are interesting and indicate novel properties of supercritical fluids in this respect. The more general problem, however, lies in determining the solubility of multicomponent solids in supercritical fluids. Experimental data have now been obtained on the solubilities of binary, solid hydrocarbon mixtures in both supercritical carbon dioxide and supercritical ethylene. Most of the behavior exhibited by pure solids in supercritical fluids still exists for multicomponent solid solute systems (e.g., retrograde solidification, solubility extrema), but new phenomena were also found. The most interesting finding is that the solubility of a solid component when in a multicomponent solute system can be as much as 300% higher than the component solubility in a pure solid system at the same operating conditions. The multicomponent-solid-fluid data usually correlate well with thermodynamic theory. 相似文献
52.
The number of vertices in a digraph G having a particular outdegree (indegree) is called the frequency of the outdegree (indegree). A set F of distinct positive integers {f1, f2, …, fn} is the frequency set of the digraph G if every outdegree and indegree occurs with frequency fj∈F and for each fj∈F there is a least one outdegree and at least one indegree with frequency fj. We prove that each nonempty set F of positive integers is the frequency set of some tournament, and we determine the smallest possible order for such a tournament. Similar results for asymmetric digraphs are also given. The results and techniques for frequency sets are used to derive corresponding results for vertex frequency partitions. 相似文献
53.
J. Reid J. Shewchun B. K. Garside 《Applied Physics A: Materials Science & Processing》1978,17(4):349-353
We report the first accurate measurements of the transition strengths and linewidths of the 00o2 9.4 μm sequence lines of CO2. This sequence band is found to be very similar to the regular 00o1 laser band, except for an experimentally determined factor of 1.89±0.12 increase in transition strength (if the CO2 molecule is treated as a simple harmonic oscillator the theoretical increase in transition strength is 2.0). The laser absorption
spectrometer used for these measurements can detect absorption coefficients in CO2 of ≈10−7 m−1, and we discuss the feasibility of using this sensitivity to monitor rare isotopic forms of CO2.
Work supported by the Department of National Health and Welfare, Environment Canada, Ontario Ministry of the Environment,
and Atmospheric Environment Service, Environment Canada. 相似文献
54.
James L. Reid 《Physics letters. A》1983,97(8):309-310
An autonomous system of n coupled homogeneous Riccati equations of the projective type linearizes to its linear part by means of a map which is analytic for almost all initial data. The explicit form of the map is presented. 相似文献
55.
Ledieu J Hoeft JT Reid DE Smerdon JA Diehl RD Lograsso TA Ross AR McGrath R 《Physical review letters》2004,92(13):135507
An ultrathin film with a periodic interlayer spacing was grown by the deposition of Cu atoms on the fivefold surface of the icosahedral Al70Pd21Mn9 quasicrystal. For coverages from 5 to 25 monolayers, a distinctive quasiperiodic low-energy electron diffraction pattern is observed. Scanning tunneling microscopy images show that the in-plane structure comprises rows having separations of S=4.5+/-0.2 A and L=7.3+/-0.3 A, whose ratio equals tau=1.618... within experimental error. The sequences of such row separations form segments of terms of the Fibonacci sequence, indicative of the formation of a pseudomorphic Cu film. 相似文献
56.
Reported herein is an example of a solution-state cross-coupling cyclization with an outcome mediated by perfluorophenyl-phenyl electrostatic interactions. 相似文献
57.
Grainger Reid J. Ko Samuel Koslov Eugene Prokop Ales Tanner Robert D. Loha Veara 《Applied biochemistry and biotechnology》2000,84(1-9):761-768
Human insulin in zinc suspension was used as a model protein to test the effect of shear on the settling rate of proteins,
a possible inference for protein denaturation. The rate of settling was determined directly in a spectropho-tometer. Shear
effects are important in retaining the activity of proteins and are present in bubble, foam, and droplet protein fractionation
processes. A sim pletest, such as that conducted here, mayeven be useful for monitoring changes in protein structure caused
by commercial shipping of the protein. The settling ratefor insulin was continously monitored in theoriginal bottle by spectrophotometric
absorbance changes as a function of time. A settling curve was determined following each shear experiment, which included
shaking the “worked” insulin solution in a vortex mixer for different lengths of time. It was determined, when comparing long
shaking times with short ones, that the initial settling rate was less for the long-term shaking of the insulin samples and
greater for the short-term shaking. The secondary effects of light and heat, along with shaking, a pparently did not produce
differences from shaking alone. 相似文献
58.
Ivan D. Reid Lap Y. Lee David M. Garner Donald J. Arseneau Masa Senba Donald G. Fleming 《Hyperfine Interactions》1986,32(1-4):801-806
This paper reports preliminary new measurements of the thermal reaction rate constants of muonium (Mu) with hydrogen and deuterium
gases in the range 480–675 K. From Arrhenius plots of the measured reaction rate constants new values of the pre-exponential
factors log10 (A) and activation energies Ea have been determined for these reactions, representing a significant improvement over earlier results. 相似文献
59.
60.
E. Emmet Reid 《Analytical and bioanalytical chemistry》1921,60(9-10):369-369