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1.
Vito Gigante Laura Aliotta Maria Beatrice Coltelli Patrizia Cinelli Luigi Botta Francesco Paolo La Mantia Andrea Lazzeri 《Journal of polymer science. Part A, Polymer chemistry》2020,58(23):3264-3282
The development of biodegradable materials for tailored applications, particularly in the field of polymeric films and sheets, is a challenging technological goal as well as a contribution to help protect the environment. Poly(lactic) acid (PLA) is a promising substitute for several oil-based polymers; however, to overcome its thermal and mechanical drawbacks, researchers have developed solutions such as blending PLA with polybutylene adipate terephthalate (PBAT), which is capable of increasing the ductility of the final material. In this study, PLA/PBAT binary blends, with minimum possible content of nonrenewable materials, were examined from processing, thermal, morphological, and rheological perspective. An optimized PLA/PBAT ratio was chosen as the polymeric basis to obtain a biodegradable formulation by adding a biobased plasticizer and appropriate fillers to produce a micrometer film with tailored flexibility and tear resistance. The processing technology involved flat-die extrusion, followed by calendering. The tearing resistance of the produced film was investigated, and the results were compared with literature data. A study on the essential work of fracture was implemented to explore the mode III out-of-plane fracture resistance starting from a trouser tear test. 相似文献
2.
3.
Summary Epitaxial films of YBa2Cu3O7−x
were depositedin situ on LaAlO3 substrates using single-target 90° off-axis sputtering. The films were characterized by magnetization measurements (M vs. T, H), applying the field parallel toc-axis. The observed differences in theT
c andJ
c values are attributed to the different oxygen content in the superconducting films.
Paper presented at the ?VII Congresso SATT?, Torino, 4–7 October 1994. 相似文献
4.
5.
Infinite dimensional duality and applications 总被引:2,自引:0,他引:2
Patrizia Daniele Sofia Giuffrè Giovanna Idone Antonino Maugeri 《Mathematische Annalen》2007,339(1):221-239
The usual duality theory cannot be applied to infinite dimensional problems because the underlying constraint set mostly has
an empty interior and the constraints are possibly nonlinear. In this paper we present an infinite dimensional nonlinear duality
theory obtained by using new separation theorems based on the notion of quasi-relative interior, which, in all the concrete
problems considered, is nonempty. We apply this theory to solve the until now unsolved problem of finding, in the infinite
dimensional case, the Lagrange multipliers associated to optimization problems or to variational inequalities. As an example,
we find the Lagrange multiplier associated to a general elastic–plastic torsion problem. 相似文献
6.
Patrizia Cenci 《Czechoslovak Journal of Physics》1991,41(3):209-235
This paper presents results on the production and decay properties of the Intermediate Vector Bosons (IVB)W and Z0 and on the search of the top quark in the upgraded UA 2 detector at the CERNp¯p Collider. The analysed data have been taken in the 1988 and 1989 Collider running periods at the centre of mass energy of 630 GeV, and correspond to an integrated luminosity of 7·4 pb–1. 相似文献
7.
This paper presents the preliminary results obtained using an Electron Paramagnetic Resonance imaging apparatus operating at 280 MHz. The acquisition technique and the procedure used to obtain the spin density spatial localization are presented and specimen images of extended samples are given. The accuracy of the images and the spatial resolution are also discussed. 相似文献
8.
The periodic unfolding method was introduced in 2002 by D. Cioranescu et al. for the study of classical periodic homogenization. In this Note, we extend this method to perforated domains introducing also a boundary unfolding operator. As an application, we study the homogenization of some elliptic problems with Robin condition on the boundary of the holes. To cite this article: D. Cioranescu et al., C. R. Acad. Sci. Paris, Ser. I 342 (2006). 相似文献
9.
Anna Rizzolo Patrizia Lombardi Maristella Vanoli Stefano Polesello 《Journal of separation science》1995,18(5):309-314
Capillary GC/sensory analysis was used to judge if dynamic headspace on sliced pulp and on intact fruit, and solvent extraction could collect the “character impact” and the “contributory” aroma compounds in peaches. Capillary GC/sensory data showed that the headspace techniques selectively recovered the “contributory” volatile compounds, which are strictly related to the characteristic odor of the various peach cultivars, whereas solvent extraction better quantified the “character impact” compounds (lactones). 相似文献
10.
The application of a new technique to the separation of some actinide elements by means of a single reducing and extracting column is described. Tri-n-octylphosphine oxide (TOPO) was used as the extractant. The following reducing agents were supported on microporous polyethylene together with TOPO: tetrachlorohydroquinone, 2,3-dichloro-1,4-naphthahydroquinone, 2,5-di-tert-butylhydroquinone and 2,5-di-tert-pentylhydroquinone. The last compound was chosen for the separation experiments; it allowed quantitative reduction of plutonium to Pu(III) and of neptunium to Np(IV). The separations Pu(III)-Np(IV), Pu(III)-U(VI) and Am(III)-Np(IV) in 6 M hydrochloric acid were obtained. 相似文献