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91.
Faoro R Kadankov M Parisi D Veronesi S Tonelli M Petrov V Griebner U Segura M Mateos X 《Optics letters》2012,37(9):1517-1519
Stable passive Q-switching of a Tm: LiYF4 laser is obtained using polycrystalline Cr2+: ZnS as a saturable absorber. The achieved maximum pulse energy of 0.9 mJ and peak power of 65 kW for a pulse duration of ~14 ns represent substantial improvement and highest values for a passively Q-switched diode-pumped Tm laser operating at ~1.9 μm. 相似文献
92.
93.
Ethyl 2-diazo-4,4,4-trifluoro-3-oxobutanoate is a highly versatile intermediate for the synthesis of a wide range of trifluoromethyl heterocycles. With the use of rhodium(II) or copper(II) catalyzed carbene X-H insertion reactions as key steps, a diverse set of trifluoromethyl-oxazoles, -thiazoles, -imidazoles, -1,2,4-triazines, and -pyridines are available from the diazoketoester, either directly in a single step or with just one additional step. 相似文献
94.
Solid damping in micro electro mechanical systems 总被引:1,自引:1,他引:0
This paper focuses on the problem of the numerical evaluation of dissipation induced by thermoelastic coupling in microelectromechanical
systems. An ad hoc conceived, FE based, numerical procedure for the evaluation of the thermoelastic dissipation is proposed
and the numerical results are compared with analytical solutions. In order to introduce in the numerical response a dependence
on the size of the resonating devices, which is experimentally observed at very small dimensions, a new enhanced non-local
coupled thermoelastic model is proposed and the first results are discussed.
An erratum to this article can be found at 相似文献
95.
Hans-Jörg G. Diersch Volker Clausnitzer Volodymyr Myrnyy Rodrigo Rosati Mattias Schmidt Holger Beruda Bruno J. Ehrnsperger Raffaele Virgilio 《Transport in Porous Media》2010,83(3):437-464
The flow and deformation processes in swelling porous media are modeled for absorbent hygiene products (e.g., diapers, wipes,
papers etc.). The first part of the article derives the fundamental equations for the hysteretic unsaturated flow, liquid
absorption, and large deformation. The final set of model equations consists of balance equations of mobile and absorbed (immobile)
liquid combined with a series of constitutive relationships. The resulting equation system is strongly nonlinear and requires
advanced numerical strategies for solving. The second part of the article focuses on numerical solution and presents simulation
results for 2D and 3D applications. 相似文献
96.
Giovanni Romano Marina Diaco Raffaele Barretta 《Continuum Mechanics and Thermodynamics》2010,22(3):177-187
The First Principle of Continuum Thermodynamics is formulated as a variational condition whose test fields are piecewise constant
virtual temperatures. Lagrange multipliers theorem is applied to relax the constraint of piecewise constancy of test fields.
This provides the existence of square summable vector fields of heat flow through the body fulfilling a virtual thermal work
principle, analogous to the virtual work principle in Mechanics. The issue of compatibility of thermal gradients is dealt
with and expressed by the complementary variational condition. Primal, complementary and mixed variational inequalities leading
to computational methods in heat-conduction boundary-value problems are briefly discussed. 相似文献
97.
A quartz crystal microbalance can be used as a biosensor if biological receptor molecules (ligands) are attached to the crystal.
To improve the sensitivity, the surface area of the gold electrodes on the crystal was increased by rendering the electrodes
porous. This increased the response up to a factor of 3. A protein model system with human anti-myoglobin as ligand and sheep
skeletal myoglobin at different concentrations as analyte was used. The quartz crystal was mounted in a flow-cell, where immobilisation,
binding and regeneration of the surface were carried out. The kinetics of the model system was monitored under various experimental
conditions.
Received February 2, 2000. Revision June 30, 2000. 相似文献
98.
The dynamics of Lagrangian systems is formulated with a differential geometric approach and according to a new paradigm of the calculus of variations. Discontinuities in the trajectory, non-potential force systems and linear constraints are taken into account with a coordinate-free treatment. The law of dynamics, characterizing the trajectory in a general non-linear configuration manifold, is expressed in terms of a variational principle and of differential and jump conditions. By endowing the configuration manifold with a connection, the general law is shown to be tensorial in the velocity of virtual flows and to depend on the torsion of the connection. This result provides a general expression of the EULER-LAGRANGE operator. POINCARÉ and LAGRANGE forms of the law are recovered as special cases corresponding, respectively, to the connection induced by natural and mobile reference frames. For free motions, the geodesic property of the trajectory is directly inferred by adopting the LEVI-CIVITA connection induced by the kinetic energy. 相似文献
99.
Raffaele Sacchi Giandomenico Corrado Boris Basile Daniele Mandarello Maria Luisa Ambrosino Antonello Paduano Maria Savarese Nicola Caporaso Maria Aponte Alessandro Genovese 《Molecules (Basel, Switzerland)》2022,27(22)
‘Oliva di Gaeta’ is almost certainly the most important and well-known PDO denomination for table olives in Italy. Their production is based on a specific two-stage trade preparation called the ‘Itrana’ method. In this work, we investigated how variations in the duration of the initial water fermentation (i.e., 15 and 30 days) and the salt concentration (i.e., 6% and 8% NaCl) influence the chemical features, microbial dynamics, polyphenols, volatile organic compounds, and sensory features of ‘Oliva di Gaeta’. The time of the addition of salt did not affect the final concentration in the brine, but a longer initial water fermentation (before salt addition) led to lower pH values. The bacterial count constantly increased until the salt addition (i.e., either 15 or 30 days), while the yeast population peaked on day 30. Generally, the two different salt concentrations did not affect the count of microorganisms at the end of fermentation, with the only exception being a higher lactic acid bacteria count for the treatment with 6% salt added at 30 days. At commercial maturity, the crucial bitter tastant oleuropein was not completely removed from the drupes, and differences in salt concentration and the length of the first-stage water fermentation did not influence its content at the end of olive curing. Richer volatile profiles of olives were detected with higher-salt treatments, while the combination of low salt and early saline treatment provided a more distinct profile. Longer initial water fermentation caused a small increase in some phenolic compounds (e.g., iso-verbascoside, verbascoside, and hydroxytyrosol-glucoside). A panel test indicated that salt application at 30 days resulted in a more “Sour” and “Bitter” taste, irrespective of the salt concentration. The low salt concentration coupled with the late saline treatment resulted in more “Fruity” notes, probably due to the higher production of esters by lactobacilli. The slightly bitter perception of the olives was consistent with the partial removal of oleuropein. Our work revealed the characteristics of the ‘Itrana’ method and that the variation in salt concentration and its time of application changes parameters ranging from the microbial dynamics to the sensory profile. Specifically, our data indicate that 6% NaCl coupled with a longer initial water fermentation is the most different condition: it is less effective in blocking microbial growth but, at the same time, is more potent in altering the nutritional (e.g., polyphenols) and sensorial qualities (e.g., bitterness and fruitiness) of ‘Oliva di Gaeta’. 相似文献
100.
Rosa Sparaco Ewa Kdzierska Agnieszka A. Kaczor Anna Bielenica Elisa Magli Beatrice Severino Angela Corvino Ewa Gibua-Tarowska Jolanta H. Kotliska Giorgia Andreozzi Paolo Luciano Elisa Perissutti Francesco Frecentese Marcello Casertano Anna Leniak Magdalena Bujalska-Zadrony Magorzata Ozibo Raffaele Capasso Vincenzo Santagada Giuseppe Caliendo Ferdinando Fiorino 《Molecules (Basel, Switzerland)》2022,27(19)
A new series of 5-norbornene-2-carboxamide derivatives was prepared and their affinities to the 5-HT1A, 5-HT2A, and 5-HT2C receptors were evaluated and compared to a previously synthesized series of derivatives characterized by exo-N-hydroxy-5-norbornene-2,3-dicarboximidenucleus, in order to identify selective ligands for the above-mentioned subtype receptors. Arylpiperazines represents one of the most important classes of 5-HT1AR ligands, and recent research concerning new derivatives has been focused on the modification of one or more portions of such pharmacophore. The combination of structural elements (heterocyclic nucleus, propyl chain and 4-substituted piperazine), known to be critical to the affinity to 5-HT1A receptors, and the proper selection of substituents led to compounds with high specificity and affinity towards serotoninergic receptors. The most active compounds were selected for further in vivo assays to determine their functional activity. Finally, to rationalize the obtained results, molecular docking studies were performed. The results of the pharmacological studies showed that Norbo-4 and Norbo-18 were the most active and promising derivatives for the serotonin receptor considered in this study. 相似文献