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171.
Isabella Camurati Giuseppe Gioia Fabrizio Piemontesi Stefano Tartarini Alessandra Bonazza Annamaria Farotti Marcello Colonnesi 《Macromolecular Symposia》2009,282(1):101-110
Summary: The aim of this work was to study the comonomer distribution and the chemical composition distribution generated by different Ziegler-Natta (ZN) systems (different internal donors, ID, dicyclopentadienyl-dimethoxy silane, D donor, as the external donor) and to define the potentialities of different IDs to produce improved heterophasic copolymers (HECO). A methodology to quantify the amount of ethylene-propylene copolymer (EP) portion in ZN-HECO and ethylene content of the EP portion by 13C-NMR was established. By using this method, it was possible to analyze the composition of ZN-HECO obtaining results comparable to those obtained with a more complex fractionation technique. 相似文献
172.
Luisa Pellegrino Franca Marangoni Giovanna Muscogiuri Paolo DIncecco Guillaume T. Duval Cedric Annweiler Annamaria Colao 《Molecules (Basel, Switzerland)》2021,26(17)
Vitamin D is essential in assuring bone health at all stages of life, but its non-skeletal effects are also essential: This vitamin impacts the physiology of the immune system, skeletal muscles and adipose tissue, glucose metabolism, skin, cardiovascular and reproductive systems, neuro-cognitive functions and cell division. The incidence of vitamin D deficiency is widespread worldwide, at any age, in young and healthy subjects, as well as in pregnant women and the elderly population, due to several factors, including inadequate sunlight exposure, skin pigmentation and coverage, adiposity, lifestyle and low dietary intakes. To overcome this problem, the fortification of foods that are consumed on a daily basis, such as milk, is strongly advisable. This opinion paper aims to discuss, in a multidisciplinary way, the current evidence supporting the importance of vitamin D in health and disease and the role of milk as an optimal carrier of this vitamin, to promote adequate intakes, highlighting its unique physico-chemical characteristics linked to both fat globule membrane and casein micelle structure. Moreover, it addresses the impact of industrial processing and storage of consumption milk on the stability of these structures, thus in determining vitamin D bioavailability and the achievement of adequate intakes. 相似文献
173.
We study the regularity of the solutions u of a class of P.D.E., whose prototype is the prescribed Levi curvature equation in ℝ2
n
+1. It is a second-order quasilinear equation whose characteristic matrix is positive semidefinite and has vanishing determinant
at every point and for every function u∈C
2. If the Levi curvature never vanishes, we represent the operator ℒ associated with the Levi equation as a sum of squares
of non-linear vector fields which are linearly independent at every point. By using a freezing method we first study the regularity
properties of the solutions of a linear operator, which has the same structure as ℒ. Then we apply these results to the classical
solutions of the equation, and prove their C
∞ regularity.
Received: October 10, 1998; in final form: March 5, 1999?Published online: May 10, 2001 相似文献
174.
Summary By limiting equations, we prove some asymptotic stability theorems for the origin ofR
n with respect to the solutions of a differential equation
, also when the functionf is not defined forx=0. Further we examine similar problems concerning the asymptotic stability of a setM ofR
n that can be unbounded.
Work performed under the auspices of the Italian Council of Research (G.N.F.M. del C.N.R.). 相似文献
Riassunto Mediante le equazioni limiti, si dimostrano alcuni teoremi di stabilità asintotica per l'origine diR n rispetto alle soluzioni di un'equazione differenziale , anche quando la funzionef non è definita perx=0. Vengono inoltre esaminati analoghi problemi relativi alla stabilità asintotica di un insiemeM diR n anche non limitato.
Work performed under the auspices of the Italian Council of Research (G.N.F.M. del C.N.R.). 相似文献
175.
It is well known that a dynamic oligopolistic market equilibrium problem can be studied as an evolutionary variational inequality and this problem is approached as a problem of profit optimization for the firms. On the contrary, in this article, with the help of an inverse variational formulation, the behavior of control policies for an oligopolistic market equilibrium problem, whose aim is to regulate the exportation through the adjustment of taxes on the firms, is studied. This is considered as a policymaker optimization problem. More precisely, a definition of equilibrium for the firms by using the Lagrange multipliers is provided together to the optimal regulatory tax definition. Moreover an existence result is given and, at last, a numerical example is analyzed. 相似文献
176.
Noncommutative Donaldson–Thomas invariants for abelian orbifold singularities can be studied via the enumeration of instanton solutions in a six-dimensional noncommutative ${{\mathcal N}=2}$ gauge theory; this construction is based on the generalized McKay correspondence and identifies the instanton counting with the counting of framed representations of a quiver which is naturally associated with the geometry of the singularity. We extend these constructions to compute BPS partition functions for higher-rank refined and motivic noncommutative Donaldson–Thomas invariants in the Coulomb branch in terms of gauge theory variables and orbifold data. We introduce the notion of virtual instanton quiver associated with the natural symplectic charge lattice which governs the quantum wall-crossing behaviour of BPS states in this context. The McKay correspondence naturally connects our formalism with other approaches to wall-crossing based on quantum monodromy operators and cluster algebras. 相似文献
177.
The nature of paramagnetic species in nitrogen doped TiO2 active in visible light photocatalysis 总被引:1,自引:0,他引:1
Livraghi S Votta A Paganini MC Giamello E 《Chemical communications (Cambridge, England)》2005,(4):498-500
Nitrogen doped TiO2, a novel photocatalyst active in the decomposition of organic pollutants using visible light, contains two different types of paramagnetic centres (neutral NO radicals and NO2(2-) type radical ions respectively) which are likely related to specific properties of the solid. 相似文献
178.
179.
180.
Annamaria Cattaneo Luisella Bocchio-Chiavetto Roberta Zanardini Eleonora Marchina Daniela Bellotti Elena Milanesi Stefania Moraschi Francesca Calabrese Sergio Barlati Marco Andrea Riva Massimo Gennarelli 《BMC neuroscience》2010,11(1):1-5