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81.
G. Tabacaru B. Borderie P. Désesquelles M. Pârlog M. F. Rivet R. Bougault B. Bouriquet A. M. Buta E. Galichet B. Guiot P. Lautesse N. Le Neindre L. Manduci E. Rosato B. Tamain M. Vigilante J. P. Wieleczko 《The European Physical Journal A - Hadrons and Nuclei》2003,18(1):103-116
Enhanced production of events with almost equal-sized fragments is experimentally revealed by charge correlations in the multifragmentation of a finite nuclear system selected in 129Xe central collisions on
nat
Sn. The evolution of their weight with the incident energy: 32, 39, 45, 50 AMeV, is measured. Dynamical stochastic mean-field simulations performed at 32 AMeV, in which spinodal instabilities are responsible for multifragmentation, exhibit a similar enhancement of this kind of events. The above experimental observation evidences the spinodal decomposition of hot finite nuclear matter as the origin of multifragmentation in the Fermi energy regime.Received: 22 November 2002, Revised: 22 April 2003, Published online: 30 September 2003PACS:
25.70.Pq Multifragment emission and correlations - 24.60.Ky Fluctuation phenomenaG. Tabacaru: Present address: Cyclotron Institute, Texas A&M University, College station, Texas 77845, USA.N. Le Neindre: Permanent address: Institut de Physique Nucléaire, IN2P3-CNRS, F-91406 Orsay cedex, France. 相似文献
82.
E. Galichet F. Gulminelli D. C. R. Guinet M. F. Rivet J. F. Lecolley R. Bougault G. Auger B. Borderie B. Bouriquet A. Buta J. L. Charvet A. Chbihi J. Colin D. Cussol R. Dayras D. Durand J. D. Frankland B. Guiot S. Hudan P. Lautesse F. Lavaud N. Le Neindre O. Lopez L. Manduci J. Marie L. Nalpas J. Normand M. Pârlog P. Paw lowski E. Plagnol E. Rosato J. C. Steckmeyer B. Tamain A. Van Lauwe E. Vient C. Volant J. P. Wieleczko INDRA Collaboration 《The European Physical Journal A - Hadrons and Nuclei》2003,18(1):75-86
The transport properties of the 36Ar +58Ni system at
measured with the INDRA array, are studied within the BNV kinetic equation. A general protocol of comparison between the N-body experimental fragment information and the one-body distribution function is developed using global variables, with a special focus on charge density. This procedure avoids any definition of sources and any use of an afterburner in the simulation. We shall discuss the feasibility of such an approach and the distortions induced by the finite detection efficiency and the completeness requirements of the data selection. The sensitivity of the different global observables to the macroscopic parameters of the effective nuclear interaction will be studied in detail.Received: 21 January 2003, Published online: 5 August 2003PACS:
25.70.-z Low and intermediate energy heavy-ion reactions - 24.10.-i Nuclear reaction models and methodsN. Le Neindre: Permanent address: Institut de Physique Nuclaire, IN2P3-CNRS, F-91406 Orsay cedex, France. 相似文献
83.
Closed kernel systems of the coalition matrix turn out to correspond to cones of games on which the core correspondence is
additive and on which the related barycentric solution is additive, stable and continuous. Different perfect cones corresponding
to closed kernel systems are described.
Received: December 2001/Revised: July 2002
RID="*"
ID="*" This note contains the new results, which were presented by the first author in an invited lecture at the XIV Italian
Meeting on Game Theory and Applications in Ischia, July 2001. The lecture was dedicated to Irinel Dragan on the occasion of
his seventieth birthday. 相似文献
84.
Y. Rojas Martinez H. Bustos Rodriguez D. Oyola Lozano G. A. Pérez Alcázar J. C. Paz 《Hyperfine Interactions》2007,175(1-3):29-34
The alloys between a transition metal and a rare earth present magnetic and magneto optical properties of exceptional interest for the production of magnetic devices for information storage. In this work we report the magnetic and structural properties, obtained by Mössbauer spectrometry (MS) and X-ray diffraction (XRD), of Tb0.257?x Nd x Fe0.743 alloys with x?=?0 and 0.257 prepared by mechanical alloying during 12, 24 and 48 h, to study the influence of the milling time in their magnetic and structural properties. The X-rays results show for all the samples that the α-Fe and an amorphous phase are always present. The first decreases and the second increases with the increase of the milling time. Mössbauer results show that the amorphous phase in samples with Nd is ferromagnetic and appears as a hyperfine field distribution and a broad doublet, and that as the milling time increases the paramagnetic contribution increases. For samples with Tb the amorphous phase is paramagnetic and appears as a broad doublet which increases with the milling time and for 48 h milling it appears an additional broad singlet. 相似文献
85.
J. D. Betancur-Ríos J. A. Tabares G. A. Pérez Alcázar V. F. Rodríguez 《Hyperfine Interactions》2007,175(1-3):63-70
Experimental analysis of magnetic and structural properties of Fe–Mn–Al–C–Cu alloys with compositions Fe x Mn0.915???x Al0.075C0.01 (series A) and Fe x Mn0.912???x Al0.075C0.01Cu0.003 (series B), 0.500?≤?x?≤?0.800, in steps of 0.050 is presented and discussed. The analysis was performed by integral conversion electrons Mössbauer spectrometry and X-ray diffraction at room temperature. The results suggest, for both series of alloys, that for the highest Mn content, samples exhibit an antiferromagnetic behavior, typical of the FCC or austenite FeMn phase rich in Mn; for those of low Mn content, the coexistence of paramagnetic austenite, typical of the FeMn alloy poor in Mn, a ferromagnetic BCC or ferrite phases can be observed, while for the lowest Mn content, only ferromagnetic (FM) phase tends to prevail. The FM phase is associated to the BCC FeMnAl as was corroborated by X-ray diffraction. The samples with the highest Mn content, the influence of Cu addition is to reduce the mean hyperfine field and to stabilize the antiferromagnetic behavior. 相似文献
86.
Lorena M. A. Silva Elenilson G. A. Filho Sérgio S. Thomasi Bianca F. Silva Antonio G. Ferreira Tiago Venâncio 《Magnetic resonance in chemistry : MRC》2013,51(9):541-548
The informal (and/or illegal) e‐commerce of pharmaceutical formulations causes problems that governmental health agencies find hard to control, one of which concerns formulas sold as natural products. The purpose of this work was to explore the advantages and limitations of DOSY and HPLC–UV–SPE–NMR. These techniques were used to identify the components of a formula illegally marketed in Brazil as an herbal medicine possessing anti‐inflammatory and analgesic properties. DOSY was able to detect the major components present at higher concentrations. Complete characterization was achieved using HPLC–UV–SPE–NMR, and 1D and 2D NMR analyses enabled the identification of known synthetic drugs. These were ranitidine and a mixture of orphenadrine citrate, piroxicam, and dexamethasone, which are co‐formulated in a remedy called Rheumazim that is used to relieve severe pain, but it is prohibited in Brazil because of a lack of sufficient pharmacokinetic and pharmacodynamic information. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
87.
Ahmed Oueslati Hatem Ben Romdhane Vincent Martin Fréderic Schiets Régis Mercier Refaât Chaâbouni 《Journal of polymer science. Part A, Polymer chemistry》2011,49(9):1988-1998
A novel pentamethylated norbornadiene (NBD) based dianhydride, α,α′‐bis‐(3,4,5,6,7‐pentamethylcyclopenta‐2,4‐dienyl)meta‐xylene‐1,2‐dianhydride (3), was prepared from α,α′‐bis‐(pentamethylcyclopentadienyl)meta‐xylene (1) and acetylene dicarboxylic acid. The bis‐adduct formed via Diels–Alder reaction afforded tetra‐acid (2), which was chemically cyclodehydrated to lead the targeted dianhydride (3). New polyimides containing NBD moieties in the main chain were prepared from the dianhydride monomer (3) and various aromatic diamines. The chemical structure of the polymers was confirmed by both 1H and 13C NMR analysis. Their Molecular weights were also measured by SEC. All of these polyimides are soluble at room temperature in common organic solvents, such as chloroform, dichloromethane, THF, DMSO, DMF, and NMP, and show good thermal stabilities. The photochemical isomerization of the NBD into quadricyclane (QC) was investigated by UV/vis spectrophotometry from polymer films using visible sunlight as irradiation source. It was found that the kinetic rate of the conversion NBD‐QC which proceeded smoothly is a first kinetic order. The stored energies released by the transformation of QC groups into NBD ones of the irradiated polymer films were also evaluated by DSC measurement and were found to be around 90 kJ mol?1. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
88.
Bogdan Constantinescu Angela Vasilescu Martin Radtke Uwe Reinholz Claire Pacheco Laurent Pichon Ernest Oberländer-Târnoveanu 《Applied Physics A: Materials Science & Processing》2012,109(2):395-402
A thorough microscopic investigation by SR XRF and micro-PIXE brings insight into the probable techniques used in the manufacture of thirteen Dacian gold bracelets, one of the most spectacular archaeological finds ever on the territory of Romania. 相似文献
89.
Photooxidation of glycated and non‐glycated phosphatidylethanolamines monitored by mass spectrometry
Tânia Melo Eduarda M. P. Silva Cláudia Simões Pedro Domingues M. Rosário M. Domingues 《Journal of mass spectrometry : JMS》2013,48(1):68-78
Phosphatidylethanolamines (PE) are one of the major components of cells membranes, namely in skin and in retina, that are continuously exposed to solar UV radiation being major targets of photooxidation damage. In addition, due to the presence of the free amine group, PE can also undergo glycation, in hyperglycemic conditions which may increase the susceptibility to oxidation. The aim of this study is to develop a model, based on mass spectrometry (MS) analysis, to identify photooxidative degradation of selected PE (POPE: PE 16:0/18:1, PLPE: PE 16:0/18:2, PAPE: PE 16:0/20:4) and glycated PEs due to UV irradiation. Photooxidation products were analysed by electrospray ionization MS (ESI‐MS) and tandem MS (ESI‐MS/MS) in positive and negative mode. Emphasis is placed in the influence of glycation in the generation of distinct photooxidation products. ESI‐MS spectra of PE after UV photo‐irradiation showed mainly hydroperoxy derivatives, due to oxidation of unsaturated fatty acyl chains. Glycated PE gave rise to several new photooxidation products formed due to oxidative cleavages of the glucose moiety, namely between C1 and C2, C2 and C3, and C5 and C6 of this sugar unit. These new products were identified by ESI‐MS/MS in positive mode showing distinct neutral loss depending on the different structure of the polar head group. These new identified advanced glycated photooxidation products may have a deleterious role in the etiology of diabetic retinopathy and in diabetic retinal microvascular complications. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
90.
Jânos Buchholcz 《Colloid and polymer science》1935,70(2):200-202
Zusammenfassung Gelatine bildet mit Chinon bei bestimmten Temperaturen und Konzentrationen ein irreversibles Gel. Die Gelbildung erfolgt um
so schneller, je h?her die Temperatur bei sonst konstanten Verh?ltnissen ist. Die Gelbildung ist wahrscheinlich auf gerbungs?hnliche
Oxydationsprozesse zurückzuführen. Das Chinon-Gelatine-Gel kann in gewisser Hinsicht als ein Modell der Blutgerinnung angesehen
werden. Hydrochinon salzt Gelatine aus. 相似文献