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Jorge Horas Cristina Di Pasquale Ezio Marchi 《Journal of Mathematical Analysis and Applications》1982,89(1):107-128
The growth of microbial cultures is studied by means of stochastic processes. A compartment structure is used to take into account cell maturation stages, having an inflow of cells from one compartment to the next. Dilution and cell division are also considered. A differential equation, first proposed by Kiefer, is studied and the expected number of cells in each compartment is found for several interesting cases. 相似文献
64.
Ruggieri F Fanelli M Di Pasquale D Burri E Petitta M Mazzeo P 《Annali di chimica》2005,95(9-10):607-616
In the present work are reported the results of a monitoring on a vast scale, carried out through evaluation of opportune chemical parameters, of the pollution state of the agricultural-industrial settlement of the Fucino Plain. The parameters took into consideration have been the presence of wide consumption pesticides and of ionic species as Cl-, NO2-, NO3-, NH4+, the quantification of the dissolved oxygen, of the temperature, of the conductivity, of pH and eH. Collected data are used for chemometric elaboration. The water systems examined, by means of drawing campaigns carried out at regular intervals in winter, spring, summer, and autumnal seasons, are represented by superficial waters constituting a network of irrigation canals fed by stratum and meteoric waters. In this work are reported the results relative to the drawing campaigns. 相似文献
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Bergese P Alessandri I Bontempi E Depero LE Aronne A Fanelli E Pernice P Ballaran TB Miyajima N Sigaev VN 《The journal of physical chemistry. B》2006,110(51):25740-25745
In potassium niobiosilicate (KNS) glasses, nanostructuring can be driven and controlled by thermal treatments at the glass transition temperature and/or by modulation of the chemical composition. The tight relationship between nanostructure and nonlinear optical properties suggests these bulk nanomaterials as an appealing route to nanophotonics. The focus of this paper is placed on assessing the phase transformations which occur in these materials upon annealing at the glass transition temperature and subsequent heating. High-temperature resolved X-ray diffraction (HTXRD) and high-resolution transmission electron microscopy (HRTEM) experiments are integrated with previously published results for in-depth insight. It will be shown that nanostructuring evolves from nucleation of niobium-rich nanocrystals, which are up to 20 nm large, uniformly distributed in the matrix bulk, and metastable. Formation kinetics as well as phase transformation of the nanocrystals are determined by the glass composition. Depending on it, nanocrystal nucleation can be preceded or not by phase separation, and the nanocrystals' phase transition can be of first or second order. 相似文献
68.
Pasquale Avella Maurizio Boccia Igor Vasilyev 《Computational Optimization and Applications》2010,45(3):543-555
The Generalized Assignment Problem is a well-known NP-hard combinatorial optimization problem which consists of minimizing
the assignment costs of a set of jobs to a set of machines satisfying capacity constraints. Most of the existing algorithms
are of a Branch-and-Price type, with lower bounds computed through Dantzig–Wolfe reformulation and column generation. 相似文献
69.
Pasquale Candito 《Rendiconti del Circolo Matematico di Palermo》2006,55(1):43-52
We use critical point theory to establish the existence of at least two solutions to a nonlinear Neumann problem involving
the one-dimensional p-Laplacian without assuming asymptotic conditions at infinity on the nonlinearity. 相似文献
70.
The existence of infinitely many solutions for a discrete non-linear Dirichlet problem involving the p-Laplacian, under appropriate oscillating behaviours of the non-linear term, is established. The approach is based on the critical point theory. 相似文献