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171.
Marielle Christiansen Kjetil Fagerholt Truls Flatberg Øyvind Haugen Oddvar Kloster Erik H. Lund 《European Journal of Operational Research》2011
This paper considers a maritime inventory routing problem faced by a major cement producer. A heterogeneous fleet of bulk ships transport multiple non-mixable cement products from producing factories to regional silo stations along the coast of Norway. Inventory constraints are present both at the factories and the silos, and there are upper and lower limits for all inventories. The ship fleet capacity is limited, and in peak periods the demand for cement products at the silos exceeds the fleet capacity. In addition, constraints regarding the capacity of the ships’ cargo holds, the depth of the ports and the fact that different cement products cannot be mixed must be taken into consideration. A construction heuristic embedded in a genetic algorithmic framework is developed. The approach adopted is used to solve real instances of the problem within reasonable solution time and with good quality solutions. 相似文献
172.
Surface-dependent chemical equilibrium constants and capacitances for bare and 3-cyanopropyldimethylchlorosilane coated silica nanochannels 总被引:1,自引:0,他引:1
Andersen MB Frey J Pennathur S Bruus H 《Journal of colloid and interface science》2011,353(1):301-310
We present a combined theoretical and experimental analysis of the solid-liquid interface of fused-silica nanofabricated channels with and without a hydrophilic 3-cyanopropyldimethylchlorosilane (cyanosilane) coating. We develop a model that relaxes the assumption that the surface parameters C(1), C(2), and pK(+) are constant and independent of surface composition. Our theoretical model consists of three parts: (i) a chemical equilibrium model of the bare or coated wall, (ii) a chemical equilibrium model of the buffered bulk electrolyte, and (iii) a self-consistent Gouy-Chapman-Stern triple-layer model of the electrochemical double layer coupling these two equilibrium models. To validate our model, we used both pH-sensitive dye-based capillary filling experiments as well as electro-osmotic current-monitoring measurements. Using our model we predict the dependence of ζ potential, surface charge density, and capillary filling length ratio on ionic strength for different surface compositions, which can be difficult to achieve otherwise. 相似文献
173.
Experiments are performed on glass/polyester composites under fatigue loading. The stiffness degradation is recorded as an indirect measure of material damage. The stiffness decrease rate is described by a power dependence on stress; this relationship allows the fatigue law to be derived. Stiffness-controlled fatigue curves are generated and presented in an S-N-diagram based on normalized stress (equivalent to strain). Such stiffness controlled fatigue curves can be used as a basis for design criteria for components.Presented at the 9th International Conference on Mechanics of Composite Materials, 17–20 October 1995, Riga, Latvia.Materials Department, Risø National Laboratory, Roskilde, Denmark. Published in Mekhanika Kompozitnykh Materialov, Vol. 32, No. 1, pp. 32–41, January–February, 1996. 相似文献
174.
L.H. Andersen A. Lapierre S.B. Nielsen I.B. Nielsen S.U. Pedersen U.V. Pedersen S. Tomita 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,20(3):597-600
Absorption of gas-phase biomolecules has been studied at the heavy-ion storage ring ELISA. Here we discuss the absorption
characteristics of the chromophores of the Green Fluorescent Protein (GFP). The gas-phase absorption maximum of the deprotonated
chromophore (anion form) is at 479 nm. This is almost identical to one of the two absorption maxima of the protein, being
at 477 nm, which is ascribed to a deprotonated chromophore in the protein. The protonated chromophore (cation form) has a
maximum at 406 nm in the gas phase. We compare the gas-phase results with absorption profiles of GFP and chromophores in liquids,
and argue that the absorption characteristics of GFP are mainly ascribed to intrinsic chemical properties of the chromophore.
Evidently, the special β-can structure of GFP provides shielding of the chromophore from the surroundings without significantly
changing the electronic structure of the chromophore through interactions with amino acid side chains.
Received 28 December 2001 Published online 13 September 2002 相似文献
175.
Inventiones mathematicae - 相似文献
176.
B. Concina S. Tomita J. U. Andersen P. Hvelplund 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2005,34(1-3):191-194
A delayed ionisation experiment has been carried out on laser excited C70 molecules. Ions and electrons are detected in coincidence to distinguish the ionisation of C70 from that of C68 molecules created by the dominant process, emission of C2. From the time dependence of the C70+ yield and the ratio to the C68+ yield, we can deduce both the dissociation energy, Ed = 9.7 ±0.3 eV, and the pre–exponential factor, Ad = 1.7 ×1020 s-1, in the Arrhenius decay law for C2 emission. The power of photon emission from neutral C70 is also determined. 相似文献
177.
F. Pétrélis F. Lund 《The European Physical Journal B - Condensed Matter and Complex Systems》2003,35(3):291-294
We investigate the effect of a localized magnetic field on the propagation of sound in an infinite fluid described by the magnetohydrodynamic equations (MHD). An externally imposed magnetic field will scatter an acoustic wave, and the scattered wave is related to the spatial structure of the magnetic field. Measuring it is thus a non-intrusive probe for the magnetic field. Simple examples likely to be encountered in practice are worked out, and estimates are given that suggest the practical feasability of this diagnostic tool in current MHD experiments.Received: 1 May 2003, Published online: 15 October 2003PACS:
42.25.Fx Diffraction and scattering - 47.65.+a Magnetohydrodynamics and electrohydrodynamics - 52.35.Dm Sound waves 相似文献
178.
E. Samsøe P. M. Petersen S. Andersson-Engels P. E. Andersen 《Applied physics. B, Lasers and optics》2005,80(7):861-864
A frequency-doubled laser diode system for generation of blue–UV light is described. The system is based on an external-cavity high-power laser diode with double feedback from the zeroth and the first orders of a diffraction grating. Light at 405 nm is generated in a single-pass configuration using periodically poled KTiOPO4. We show that the double grating feedback improves the second harmonic conversion efficiency by several orders of magnitude as compared to the freely running laser. The conversion efficiency may be improved further such that higher second-harmonic powers may be generated. 相似文献
179.
R. Albrecht T. C. Awes C. Baktash P. Beckmann F. Berger R. Bock G. Claesson G. Clewing L. Dragon R. L. Ferguson A. Franz S. Garpman R. Glasow H. ?. Gustafsson H. H. Gutbrod K. H. Kampert B. W. Kolb P. Kristiansson I. Y. Lee H. L?hner I. Lund F. E. Obershain A. Oskarsson I. Otterlund T. Peitzmann S. Persson F. Plasil A. M. Poskanzer M. Purschke H. G. Ritter R. Santo H. R. Schmidt T. Siemiarczuk S. P. S?rensen E. Stenlund G. R. Young WA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1990,47(3):367-375
The production of neutral pions by the interaction of 200A·GeV p and16O projectiles with a Au target has been studied in the pseudorapidity range 1.5≦η≦2.1. Transverse momentum spectra have been measured between 0.4 GeV/c and 3.6 GeV/c and their dependence on the centrality of the collision has been investigated. The peripheral-collision spectra display a marked change of slope with a hard component starting at about 1.8 GeV/c, in contrast to central-collision data. The data are discussed in comparison to p+p and α+α data from the ISR. 相似文献
180.
Kerry Lee Lawrence Pinsky Vic Andersen Cary Zeitlin Tim Cleghorn Frank Cucinotta Premkumar Saganti William Atwell Ron Turner 《Radiation measurements》2006,41(9-10):1123-1125
The helium energy spectrum in Martian orbit has been observed by the MARIE charged particle spectrometer aboard the 2001 Mars Odyssey spacecraft. The orbital data were taken from March 13, 2002 to October 28, 2003, at which time a very intense Solar Particle Event caused a loss of communication between the instrument and the spacecraft. The silicon detector stack in MARIE is optimized for the detection of protons and helium in the energy range below , which typically includes almost all of the flux during SPEs. This also makes MARIE an efficient detector for GCR helium in the energy range of 50–. We will present the first fully normalized flux results from MARIE, using helium ions in this energy range. 相似文献