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551.
R. Bianchi D. Bressanini P. Cremaschi M. Mella G. Morosi 《International journal of quantum chemistry》1994,50(6):401-410
The problems connected with the simulation by the diffusion quantum Monte Carlo method of atomic and molecular systems in the two-dimensional (2D ) space have been investigated on the 1 2S and 2 2S states of the hydrogen atom and on the 1 1S and 1 3S states of the helium atom, assuming r?1 Coulomb interactions between the particles. The potential surface of the 1Σg+ state of the 2D hydrogen molecule has been calculated in the range 0.1–1.5 bohr: A dissociation energy of 1.2703 Hartrees is found at the equilibrium distance of 0.3639 bohr. © 1994 John Wiley & Sons, Inc. 相似文献
552.
Giselle Bianchi Alfredo Marzocchi 《NoDEA : Nonlinear Differential Equations and Applications》1998,5(2):181-192
We consider a strongly damped semilinear equation arising in the theory of elastic beams. We prove the existence of an exponentially
attracting finite-dimensional vector space in the Hilbert space of the solutions (a so-called inertial manifold), and provide
some numerical estimates of the dimension of the manifold.
Received January 20, 1997. 相似文献
553.
M.P. Fontana P.P. Lottici C. Razzetti D. Bianchi G. Antonioli U. Emiliani 《Solid State Communications》1982,43(7):561-565
EXAFS measurements at different temperatures on amorphous arsenic are reported. The low values of the EXAFS mean square relative displacement σ2 for the first coordination shell are consistent with a distribution of As4 pyramidal units throughout the amorphous network, giving a locally very ordered first shell, whose disorder is essentially dynamic in character. The temperature dependence of the vibrational contribution to the EXAFS Debye-Waller factor is well described by an Einstein oscillator model. 相似文献
554.
Umberto Bianchi Carla Cuniberti Enrico Pedemonte Corrado Rossi 《Journal of Polymer Science.Polymer Physics》1969,7(5):845-853
The conformational energy contribution (ΔUconf) to the heat of solution in polymer-solvent systems is presented and discussed in connection with chain conformational properties. In particular, ΔUconf has been discussed in terms of various possible mechanisms of coil deformation. 相似文献
555.
We classify all finite groups whose subgroup-permutability graph is the incidence graph of an affine plain. 相似文献
556.
Arnone Massimo Bianchi Michele Leonardo Quaranta Anna Grazia Tassinari Gian Luca 《Computational Management Science》2021,18(2):213-237
Computational Management Science - In this paper, after a review of the most common financial strategies and products that insurance companies use to hedge catastrophic risks, we study an option... 相似文献
557.
S. Barlag P. van Dam E. De Wolf B. Jongejans A. Tenner C. Visser R. Wigmans P. Capiluppi F. Fabbri G. Giacomelli G. Mandrioli P. Mazzanti A. M. Rossi P. Serra-Lugaresi M. Baldo-Ceolin F. Bobisut E. Calimani S. Ciampolillo H. Huzita C. Angelini L. Bertanza A. Bigi R. Casali R. Fantechi V. Flaminio A. Nappi R. Pazzi C. Petri G. Pierazzini M. Bloch T. Bolognese J. Derkaoui M. L. Faccini-Turluer A. Fridman C. Louedec L. Mosca J. Saudraix D. Vignaud D. Allasia F. Bianchi V. Bisi D. Gamba A. Marzari-Chiesa L. Ramello L. Riccati A. Romero Amsterdam-Bologna-Padova-Pisa-Saclay-Torino Collaboration 《Zeitschrift fur Physik C Particles and Fields》1982,11(4):283-292
Charged hadron multiplicity distributions in \(\bar v_\mu n\) and \(\bar v_\mu p\) interactions in the energy range \(5< E_{\bar v}< 150GeV\) GeV are presented. They are obtained from about \(6000\bar v_\mu \) charged current events produced in BEBC filled with deuterium. Multiplicity moments are studied as a function of the invariant mass of the hadronic systemW. Results on multiplicity distributions in the forward and backward directions in the hadronic c.m.s. are presented and discussed within the framework of the quark parton model. Values for the average charge of the forward jet are also determined and compared with other experimental data. 相似文献
558.
Bianchi L Maccagno M Petrillo G Sancassan F Tavani C Morganti S Rizzato E Spinelli D 《The Journal of organic chemistry》2007,72(15):5771-5777
4-Alkyl-2-nitrothiophenes [10: R = CH3, CH(OH)CH3, CH(OCH3)CH3] react with secondary aliphatic amines, in the presence of AgNO3, to give 3-alkyl-2-amino-5-nitrothiophenes (12) through an oxidative nucleophilic substitution of hydrogen (ONSH) of synthetic interest. This behavior is in striking contrast with that of the parent 2-nitrothiophene (6), which was found to undergo ring-opening in analogous reaction conditions. A possible rationale for the crucial effect of alkyl groups is suggested, grounded also on a study of the corresponding Meisenheimer-like adducts. 相似文献
559.
Sacchetti G Muzzoli M Statti GA Conforti F Bianchi A Agrimonti C Ballero M Poli F 《Natural product research》2007,21(2):167-179
Methanolic extracts of Myrtus communis leaves from two Italian regions (Calabria and Sardinia) were processed to determine the content of myrtenol, linalool and eucalyptol. Among the Calabrian and Sardinian myrtle samples, linalool and eucalyptol chemotypes were prevalent. The extracts were also tested for antioxidant, antibacterial and antifungal activities. Myrtle leaves samples were dried and extracted through maceration. Partition chromatography was adopted to separate myrtenol, linalool and eucalyptol fractions. Analyses were performed through GC and GC-MS. Some of the samples showed a good scavenger activity evidenced by DPPH radical scavenging assay and beta-carotene bleaching test. Antibacterial and antifungal activities were generally weak. The phytochemical and biological characterization of all the extracts were determined with an aim to characterize the intra-specific biodiversity of myrtle populations. 相似文献
560.
Valter Castelvetro Mustapha RaihaneSabrina Bianchi Salima AtlasIlaria Bonaduce 《Polymer Degradation and Stability》2011,96(2):204-211
The thermal decomposition under non-oxidative conditions of a copolymer of vinylidene cyanide (VCN) and 2,2,2-trifluoroethyl methacrylate (MATRIF) was investigated by thermogravimetry (TG) and Pyrolysis-GC-MS. The type and composition of the pyrolytic products and the shape of the TG curve indicate that both the main thermal degradation process, with onset at 368 °C, and a minor weight loss at around 222 °C are mainly associated with random main-chain scission. The kinetic parameters were determined by means of dynamic and, in the case of the main degradation stage, also isothermal methods. The results obtained from the dynamic methods (Friedman, Flynn-Wall-Ozawa, and Kissinger, respectively) are in good agreement with those obtained from isothermal TG data. The activation energy was in the 177-213 kJ/mol range for the first stage, and 224-295 kJ/mol for the second stage, the highest respective values being determined from the kinetic analysis according to the Kissinger method. 相似文献