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This paper investigates the F span of the rows of an incidence matrix of a finite projective plane. Results are obtained on the dimension and minimum weight (in the sense of algebraic coding theory) of both this span and its orthogonal.  相似文献   
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pH‐Cleavable cell‐laden microgels with excellent long‐term viabilities were fabricated by combining bioorthogonal strain‐promoted azide–alkyne cycloaddition (SPAAC) and droplet‐based microfluidics. Poly(ethylene glycol)dicyclooctyne and dendritic poly(glycerol azide) served as bioinert hydrogel precursors. Azide conjugation was performed using different substituted acid‐labile benzacetal linkers that allowed precise control of the microgel degradation kinetics in the interesting pH range between 4.5 and 7.4. By this means, a pH‐controlled release of the encapsulated cells was achieved upon demand with no effect on cell viability and spreading. As a result, the microgel particles can be used for temporary cell encapsulation, allowing the cells to be studied and manipulated during the encapsulation and then be isolated and harvested by decomposition of the microgel scaffolds.  相似文献   
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CaFeO2.5±δ single crystal was obtained after different steps of mechanical and thermal treatment and finally a crystallization in an image furnace. We performed dilatometric tests of this material according to the three crystallographic directions of the network, from ambient to 1,473 K, accompanied by DSC and TG tests. The tests performed on a single crystal CaFeO2.5 confirmed the transitions already observed by other authors. For the first time, a dilatometric anomaly has been observed at 1,308 K. It has the highest intensity of all the anomalies observed and appears only along the b crystallographic direction reflecting a change of state of CaFeO2.5 at high temperature. This anomaly was confirmed using DSC and TG analysis. Moreover, this study confirmed the important dilatometric anisotropy of the material.  相似文献   
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Smoothed Particle Hydrodynamics (SPH) is a Lagrangian method widely used for the modelling of a large variety of astrophysical fluid flows in more than one dimension. Simulations of thermonuclear explosions in stars require, besides the hydrodynamic equations, a realistic equation of state, an energy source term, and a set of nuclear kinetic equations to follow the composition changes of the gas during the explosion. The implementation of a realistic stellar equation of state, and the coupling of hydrodynamics and nuclear burning are investigated in the framework of the simple shock tube geometry. We present and discuss the results of a series of SPH simulations of a detonation in the presence of (1) a single exothermic nuclear reaction, and (2) a restricted network of nuclear reactions. Our results are compared to those of identical simulations performed by other authors using a different hydrodynamic method.  相似文献   
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