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101.
Clifton LA Sanders MR Castelletto V Rogers SE Heenan RK Neylon C Frazier RA Green RJ 《Physical chemistry chemical physics : PCCP》2011,13(19):8881-8888
The self-assembly in solution of puroindoline-a (Pin-a), an amphiphilic lipid binding protein from common wheat, was investigated by small angle neutron scattering, dynamic light scattering and size exclusion chromatography. Pin-a was found to form monodisperse prolate ellipsoidal micelles with a major axial radius of 112 ± 4.5 ? and minor axial radius of 40.4 ± 0.18 ?. These protein micelles were formed by the spontaneous self-assembly of 38 Pin-a molecules in solution and were stable over a wide pH range (3.5-11) and at elevated temperatures (20-65 °C). Pin-a micelles could be disrupted upon addition of the non-ionic surfactant dodecyl-β-maltoside, suggesting that the protein self-assembly is driven by hydrophobic forces, consisting of intermolecular interactions between Trp residues located within a well-defined Trp-rich domain of Pin-a. 相似文献
102.
Florian Hatesuer Tillmann Groth Mark Reichwage Dieter Mewes Andrea Luke 《Heat and Mass Transfer》2011,47(8):921-931
Twin-screw multiphase pumps are employed increasingly to convey multiphase mixtures of crude oil, accompanying fluids, associated
gas and solid particles. They are positive displacement pumps and suitable for handling products containing liquid accompanied
by large amounts of gas. Experimental investigations on the conveying characteristic, namely measuring the delivered volume
flow as a function of the pressure difference, provide results for selected mixtures. By means of the on hand work, the influence
of sorption phenomena occurring due to pressure variations alongside the conveying process on the conveying characteristics
of twin-screw pumps delivering mixtures of oil and gases is measured. The employed gases are air and carbon dioxide, which
differ strongly in solubility in oil. All experiments are conducted in a closed loop test facility, where oil and gas volume
flows are mixed before the inlet and separated after the outlet of the multiphase pump. In order to simulate the influence
of the suction side pressure drop in the reservoir on the conveying characteristic, packed beds are employed as oil-filed
model. Sorption processes inside of the oil-field model and within the multiphase pump affect the conveying behaviour significantly.
The two-phase flow in the inlet and outlet pipe is visualised by means of a capacitance tomography system. Results show that
the oil fraction of the total delivered volume flow is decreased due to desorption at the pump inlet. The gas fraction at
the pump outlet is further decreased due to absorption. Experimental results are compared to calculated solubilities of the
on-hand gases in oil and to the theoretically derived gas volume flow fraction expected at the multiphase pump. 相似文献
103.
Bianca Haberl Jamie J. Molaison Joerg C. Neuefeind Luke L. Daemen Reinhard Boehler 《高压研究》2013,33(3):426-437
ABSTRACTA simple modified Bridgman design for large volume pressure anvils usable in the Paris-Edinburgh (PE) press has been demonstrated at Oak Ridge National Laboratory Spallation Neutron Source. The design shows advantages over the toroidal anvils typically used in the PE press, mainly rapid compression/decompression rates, complete absence of blow-outs upon drastic phase transitions, simplified cooling, high reliability, and relative low loads (~40 tons) corresponding to relatively high pressures (~20?GPa). It also shows advantages over existing large-volume diamond cells as sample volumes of ~2–3?mm3 can be easily and rapidly synthesized. The anvils thus allow sample sizes sufficient for in situ neutron diffraction as well as rapid synthesis of adequate amounts of new materials for ex situ analysis via total neutron scattering and neutron spectroscopy. 相似文献
104.
105.
S Kailas R Vandenbosch A Charlop A Garcia S Gil S J Luke B McLain D Prindle 《Pramana》1990,35(5):439-447
The fusion cross section for the system6Li+28Si has been measured atE∼36 MeV. Combining this with the data available at lower energies, the nucleus-nucleus real potentials have been determined
for a range of interaction distances. 相似文献
106.
Richard N. Butler Denise C. Grogan Luke A. Burke 《Journal of heterocyclic chemistry》1997,34(6):1825-1827
An unusual inverted V-shaped Hammett plot has been observed for substituent effects at the N-terminus of 1,2,3-triazolium-1-imide 1,3-dipoles in cycloaddition reactions. Theoretical studies (3-21G and 6-31G) suggest strong resonance interactions separately stabilizing both ends of the dipole. 相似文献
107.
James O. Jensen Pallassana N. Krishnan Luke A. Burke 《Journal of Molecular Structure》1996,370(2-3):245-252
Twenty-two structures with the empirical formula H3CNO are presented. These structures are examined since they have the same formula as the H2O…HCN complex. The H2O…HCN potential energy surface is of interest to chemists studying the water catalyzed polymerization of HCN. Structures, thermodynamics, and vibrational spectra are examined. 相似文献
108.
109.
František Lukeš 《Czechoslovak Journal of Physics》1959,9(1):118-123
, , . .
A new method of measuring the reflectivity factor
A new method is given of measuring reflectivity and compared with methods known up to now, which are characterized briefly. The applicability and suitability of the given method is shown on an example of measurement of the reflectivity of germanium in the ultra-violet and visible regions.相似文献
110.
A rapid, accurate spectrophotometric method for the determination of 0.001–0.1% of molybdenum in steel, tantalum, niobium or tungsten is presented. The molybdenum is isolated, when required, by solvent extraction with α-benzoinoxime-chloroform solution or cupferron- chloroform solution and then determined by the thiocyanate method. Conditions for obtaining high sensitivity by quantitative reduction of molybdenum (VI) to molybdenum (V) with tin(II) chloride have been established. It has been shown that fading of the molybdenum(V)-thiocyanate color can be minimized by adding hydroquinone to prevent air oxidation of molybdenum (V). 相似文献