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31.
Monika Schuster Claudia Turecek Alexander Mateos Jürgen Stampfl Robert Liska Franz Varga 《Monatshefte für Chemie / Chemical Monthly》2007,138(4):261-268
Summary. Within these investigations a new monomer formulation – consisting of a biodegradable basis monomer, reactive diluents, fillers,
and an appropriate photoinitiator – was developed for the stereolithographic fabrication of bone replacement materials. In
the current paper we describe the testing of several acrylate based reactive diluents – having different functional groups
– concerning reactivity, biocompatibility, and mechanical properties. Polymers from tripropylene glycol diacrylate, propoxylated
glycerol diacrylate and tricyclodecan dimethanol diacrylate showed the most promising results regarding these 3 criteria.
Three-dimensional spongiosa-like structures were built by stereolithography using different monomers, fillers, and a suitable
photoinitiator. 相似文献
32.
Matthew Attard David Coral Èric Pedrol Magdalena Aguiló Francesc Díaz Xavier Mateos 《Particle & Particle Systems Characterization》2023,40(9):2300038
This work produces a unique microfluidic device that acts as a “lab on a chip,” conducting separation, mixing, and concentration of microparticles similar to that required by cell sorting flow cytometry applications. The passive two-dimensional device shows to be successful at separating polystyrene (PS) beads between 5 and 20 µm in diameter, mixing them with an external media, and concentrating them by 250% continuously with minimal sample preparation, while still being inexpensive, and effective. By implementing the microfluidic device, the processing steps are done within seconds due to its high throughput of 2 mL min−1, wherein different hydrodynamic phenomena such as Dean's forces, inertial lift forces, and enhanced diffusion are taken advantage of. 相似文献
33.
An efficient and compact diode-pumped continuous-wave Yb:GdVO4 laser is demonstrated, generating an output power of 4.0 W with an optical conversion efficiency of 61% and a slope efficiency as high as 78%. With increasing pump power the polarization of the laser output changes from sigma to pi, while in a certain intermediate power range the two polarization states coexist with different emission wavelengths. 相似文献
34.
Colour is an organoleptic characteristic of virgin olive oil and an important attribute that affects the consumer perception
of quality. Chlorophylls and carotenoids are the main pigments responsible for the colour of virgin olive oil. A simple analytical
method for the quantitative determination of chlorophylls and carotenoids in virgin olive oils has been developed. The pigments
were isolated from small samples of oil (1.0 g) by solid-phase extraction using diol-phase cartridges (diol-SPE), and the
extract was analysed by reverse-phase HPLC with diode-array UV detection. Chromatographic peak resolution, reproducibility
(coefficient of variation (C.V.) <4.5%) and recovery (>98.4%) for each component were satisfactory. A comparative study of
the proposed method was performed versus classical liquid-liquid extraction (LLE) with N,N′-dimethylformamide and solid-phase extraction using a C18 column (C18-SPE). While 96.4% of the pigments were recovered by
LLE, only 51.3% were isolated by C18-SPE in comparison to diol-SPE. Likewise, a higher alteration of pigment composition was
observed when such LLE and C18-SPE procedures were used. In this sense, a higher ratio of pheophytin in comparison to that
isolated by the diol-SPE procedure was achieved with both extraction procedures, indicating a greater extent of the pheophytinization
reaction. Therefore, quantification of pigments from virgin olive oil by diol-SPE followed by RP-HPLC was found to be rapid,
simple, required only a small amount of sample, consumed only small amounts of organic solvents, and provided high recoveries,
accuracy and precision. 相似文献
35.
36.
A. Alonso Izquierdo M.A. Gonzalez Leon M. de la Torre Mayado J. Mateos Guilarte 《Physica D: Nonlinear Phenomena》2005,200(3-4):220-241
We discuss the solitary wave solutions of a particular two-component scalar field model in two-dimensional Minkowski space. These solitary waves involve one, two or four lumps of energy. The adiabatic motion of these composite nonlinear non-dispersive waves points to variations in shape. 相似文献
37.
In this paper, we introduce a methodology based on an additive multiattribute utility function that does not call for precise estimations of the inputs, such as utilities, attribute weights and performances of decision alternatives. The information about such inputs is assumed to be in the form of ranges, which constitute model constraints and give rise to nonlinear programming problems. This has significant drawbacks for outputting the sets of non-dominated and potentially optimal alternatives for such problems, and we, therefore, propose their transformation into equivalent linear programming problems. The set of non-dominated and potentially optimal alternatives is a non-ranked set and can be very large, which makes the choice of the most preferred alternative very difficult. The above problem is solved by proposing several methods for alternative ranking. An application to the disposal of surplus weapons-grade plutonium is considered, showing the advantages of this approach. 相似文献
38.
Eduardo?CasasEmail author Mariano?Mateos Fredi?Tr?ltzsch 《Computational Optimization and Applications》2005,31(2):193-219
We study the numerical approximation of boundary optimal control problems governed by semilinear elliptic partial differential equations with pointwise constraints on the control. The analysis of the approximate control problems is carried out. The uniform convergence of discretized controls to optimal controls is proven under natural assumptions by taking piecewise constant controls. Finally, error estimates are established and some numerical experiments, which confirm the theoretical results, are performed.The first two authors were supported by Ministerio de Ciencia y Tecnología (Spain). The second author was also supported by the DFG research center “Mathematics for key technologies” (FZT86) in Berlin. 相似文献
39.
A surprising new seven-parameter supersymmetric black ring solution of five-dimensional supergravity has recently been discovered. In this paper, M theory is used to give an exact microscopic accounting of its entropy. 相似文献
40.
Rivier S Mateos X Petrov V Griebner U Aznar A Silvestre O Sole R Aguilo M Diaz F Zorn M Weyers M 《Optics letters》2005,30(18):2484-2486
Mode locking based on an epitaxial composite of the monoclinic double tungstate crystal Yb:KLu(WO4)2 is realized. A 100 microm thin Yb:KLu(WO4)2 layer grown on a KLu(WO4)2 substrate is used as an active medium in a laser passively mode locked by a semiconductor saturable absorber. Pulse durations of 114 fs have been achieved for an average power of 31 mW at 1030 nm. Results in the femtosecond and picosecond regimes of the Yb:KLu(WO4)2/KLu(WO4)2 laser are presented. The great potential of Yb-doped tungstate composite structures as active elements for mode-locked laser systems is demonstrated. 相似文献