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1.
Ahlen S Ambrosio M Antolini R Auriemma G Baker R Baldini A Bam BB Barbarino GC Barish BC Battistoni G Bellotti R Bemporad C Bernandini P Bilokon H Bisi V Bloise C Bower C Bussino S Cafagna F Calicchio M Campana D Campana P Carboni M Cecchini S Cei F Chiarella V Cormack R Corona A Coutu S De Cataldo G Dekhissi H De Marzo C De Vincenzi M Di Credico A Diehl E Erriquez O Favuzzi C Ficenec D Forti C Fusco P Giacomelli G Giannini G Giglietto N Giubellino P Grassi M Green P Grillo A Guarino F 《Physical review letters》1994,72(5):608-612
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Claudio De Rosa Finizia Auriemma Rocco Di Girolamo Odda Ruiz de Ballesteros 《Journal of Polymer Science.Polymer Physics》2014,52(10):677-699
The combination of the control of the concentration of stereodefects in isotactic polypropylene using metallocene catalysts and the crystallization via the mesophase is a strategy to tailor the mechanical properties. Stiff materials, flexible materials, and thermoplastic elastomers can be produced depending only on the concentration of rr stereodefects. Modulus, ductility, and strength can be modulated through the crystallization of α and γ forms or of the mesophase. Different morphologies are observed depending on the stereoregularity and conditions of crystallization. Crystals of the mesomorphic form always exhibit a nodular morphology, accounting for the similar good deformability of all quenched samples, whatever the concentration of stereodefects. The mesophase transforms by thermal treatments into the α form preserving the nodular morphology, with increase of strength while maintaining the ductility typical of the mesophase. Annealing of the mesophase permits a precise adjustment of crystallinity and size of nodular crystals offering additional options to modify the mechanical properties. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 677–699 相似文献
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Bergerson WF Auriemma F Chapman BE Ding WX Zanca P Brower DL Innocente P Lin L Lorenzini R Martines E Momo B Sarff JS Terranova D 《Physical review letters》2011,107(25):255001
We report the first direct measurement of the internal magnetic field structure associated with a 3D helical equilibrium generated spontaneously in the core of an axisymmetric toroidal plasma containment device. Magnetohydrodynamic equilibrium bifurcation occurs in a reversed-field pinch when the innermost resonant magnetic perturbation grows to a large amplitude, reaching up to 8% of the mean field strength. Magnetic topology evolution is determined by measuring the Faraday effect, revealing that, as the perturbation grows, toroidal symmetry is broken and a helical equilibrium is established. 相似文献
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G DAgostini G Auriemma J.P de Brion A Caillet J.B Cheze J Derré G Marel G Marini G Martellotti F Massa A Nigro E Pauli C Pigot A Rambaldi S Reucroft C.E Roos A Sciubba M Webster 《Physics letters. [Part B]》1981,104(4):330-334
The reactions π?d → K+ + MM and K?d → π+ + MM have been studied at 1.4 GeV/c to search for strange dibaryon states with quantum numbers Q = ?1, and S = ?1. No structures are found which could indicate the production of such states and upper limits for the cross sections are established. 相似文献
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Paccagnella R Ortolani S Zanca P Alfier A Bolzonella T Marrelli L Puiatti ME Serianni G Terranova D Valisa M Agostini M Apolloni L Auriemma F Bonomo F Canton A Carraro L Cavazzana R Cavinato M Franz P Gazza E Grando L Innocente P Lorenzini R Luchetta A Manduchi G Marchiori G Martini S Pasqualotto R Piovesan P Pomaro N Scarin P Spizzo G Spolaore M Taliercio C Vianello N Zaniol B Zanotto L Zuin M 《Physical review letters》2006,97(7):075001
Stable operation with control on magnetohydrodynamic modes has been obtained in the modified reversed field experiment employing a set of 192 feedback controlled saddle coils. Improvements of plasma temperature, confinement (twofold), and pulse length (threefold) and, as a consequence of the magnetic fluctuation reduction, strong mitigation of plasma-wall interaction and mode locking are reported. 相似文献
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The crystal structure of various polymers, presenting symmetry breaking, is discussed. Owing to the presence of disorder, the crystal structure of polymers is generally described in term of ideal modifications, a limit ordered form, characterized by ideal three‐dimensional order, and a limit disordered form, characterized by the presence of statistical disorder in the packing, while preserving the order in the parallelism of the chains. The real crystalline forms are generally intermediate between the limit ordered and limit disordered models. The occurrence of conformational disorder, which produce defects frozen in the crystals of syndiotactic polypropylene, is analyzed. 相似文献
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G. Russo L. Parravicini F. Auriemma V. Petraccone G. Guerra R. Bianchi G. Di Dino V. M. Vitagliano 《Journal of Polymer Science.Polymer Physics》1997,35(6):889-896
Some properties and structural aspects of fibers obtained by spinning, in a wide range of take-up speed (2,800–4,400 m/min), of commercial samples of PET, produced by dimethyl terephthalate (DMT) and the terephthalic acid (TPA) processes, are compared. For a same take-up speed, the considered fibers from TPA are spun at lower pack pressures and always show higher tenacity and lower ductility than fibers from DMT. X-ray diffraction, density, and birefringence measurements indicate that, for the fibers from the DMT process, an earlier crystallization occurs which prevents the progress of the orientation of the amorphous phase. The lower molecular orientation in the amorphous phase of the fibers from DMT, in turn, accounts for their lower tenacity. The earlier crystallization of the fibers from DMT would be related to their slightly higher melting temperatures and melt viscosities, which could be due to the lower amount of constitutional defects (diethylene glycol content) in the considered PET samples from DMT compared with those from TPA. © 1997 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 35 : 889–896, 1997 相似文献
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Summary We present the negative result of a search for the radiative decay of a light neutral fermion, that might be the neutrino
(if massive) or the photino, gravitationally bounded to our Galaxy. The limit obtained for the radiative lifetime of a particle
of mass between 12.5 and 21.5 eV is ≈1018 years. These new data on UV background in the range (1250÷2000) ? show the presence of continuum emission and diffuse lines
emission at high galactic latitude (|b
II|>45°). The lines are identifiable with C IV, λ-1549 ? and N III, λ=1749 ?. The continuum level sharply rises at 1680 ? to
the level of (314±136) photons/(cm2s sr ?) and remains nearly constant up to 2000 Å. Below 1680 Å we found no emission with an upper limit of ≈100 units. These
new data are briefly discussed in comparison with the results of previous experiments and theoretical expectations.
Paper presented at the Congress ?Galactic and Extragalactic Dark Matter?, Roma, 28 to 30 June 1983. 相似文献