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151.
Edwar Corts Rodrigo Abonía Justo Cobo Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(2):o64-o66
In the title compound, C22H21BrN4O2, the imidazole and pyrazole rings are almost orthogonal to each other, but the ester unit is effectively coplanar with the adjacent aryl rings. The molecules are linked into a chain of edge‐fused centrosymmetric rings by a combination of N—H...O and C—H...π(arene) hydrogen bonds. 相似文献
152.
Edwar Corts Rodrigo Abonía Justo Cobo Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(1):o26-o28
In the molecule of the title compound, C17H20N4O5, there are two intramolecular N—H...O hydrogen bonds having amidic and nitro‐group O atoms as the acceptors and together forming a three‐centre N—H...(O)2 system. These interactions appear to play an important role in controlling the relative orientation of the pyrazole and aryl rings. The bond distances provide evidence for some polarization of the electronic structure. Molecules are linked into simple chains by a single C—H...O hydrogen bond. 相似文献
153.
Petros Galanopoulos Daniel Girela Rodrigo Hernández 《Journal of Geometric Analysis》2011,21(3):665-682
This paper is concerned mainly with the logarithmic Bloch space ℬlog which consists of those functions f which are analytic in the unit disc
\mathbbD{\mathbb{D}} and satisfy
sup|z| < 1(1-|z|)log\frac11-|z||f¢(z)| < ¥\sup_{\vert z\vert <1}(1-\vert z\vert )\log\frac{1}{1-\vert z\vert}\vert f^{\prime}(z)\vert <\infty , and the analytic Besov spaces B
p
, 1≤p<∞. They are all subspaces of the space VMOA. We study the relation between these spaces, paying special attention to the membership of univalent functions in them. We
give explicit examples of:
• |
A bounded univalent function in $\bigcup_{p>1}B^{p}$\bigcup_{p>1}B^{p} but not in the logarithmic Bloch space. 相似文献
154.
Eduardo González-Olivares Héctor Meneses-Alcay Betsabé González-Yañez Jaime Mena-Lorca Alejandro Rojas-Palma Rodrigo Ramos-Jiliberto 《Nonlinear Analysis: Real World Applications》2011,12(6):2931-2942
In this work, a bidimensional differential equation system obtained by modifying the well-known predator–prey Rosenzweig–MacArthur model is analyzed by considering prey growth influenced by the Allee effect.One of the main consequences of this modification is a separatrix curve that appears in the phase plane, dividing the behavior of the trajectories. The results show that the equilibrium in the origin is an attractor for any set of parameters. The unique positive equilibrium, when it exists, can be either an attractor or a repeller surrounded by a limit cycle, whose uniqueness is established by calculating the Lyapunov quantities. Therefore, both populations could either reach deterministic extinction or long-term deterministic coexistence.The existence of a heteroclinic curve is also proved. When this curve is broken by changing parameter values, then the origin turns out to be an attractor for all orbits in the phase plane. This implies that there are plausible conditions where both populations can go to extinction. We conclude that strong and weak Allee effects on prey population exert similar influences on the predator–prey model, thereby increasing the risk of ecological extinction. 相似文献
155.
Rodrigo A.B. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1995,23(1):10-19
The status of plasma physics in Latin America is reviewed. The review surveys the history and present situation of the regional activities in high-temperature plasma research, plasma astrophysics, and technological applications of plasma physics. In particular, it presents data on the trends of evolution of scientific staff, annual operating budget, and publication rate for the major Latin American plasma groups during the decade 1983-1992. On this basis, the prospects for further growth and the potential for regional contribution to the mainstream of international plasma research and development are discussed 相似文献
156.
Rodrigo Lambert Oréfice Wander Luiz Vasconcelos 《Journal of Sol-Gel Science and Technology》1997,9(3):239-249
The capacity of the sol-gel process of producing highly pure, homogeneous alumina-silica based materials had been demonstrated
in the last few years. However, a full understanding on the mechanisms associated to sol formation and sol to gel transition
has not yet been achieved and is required for the development of a new generation of nano-structurally tailored materials
that will significantly enhance the technological importance of the sol-gel process. In this work, tetraethyl orthosilicate
(TEOS) and aluminum isopropoxide were used to prepare materials within the entire silica-alumina system. Process parameters,
such as gelation time, were correlated to variables of the initial stage of the process, such as pH, temperature of hydrolysis
and water/alkoxide ratio. The obtained gels were dried at 105°C and subsequently heat treated at 500 and 1100°C for 3 hours.
X-ray diffraction and infrared spectroscopy were used to characterize the materials and phase transformations. Structural
information obtained from phase characterization and phase transformations was correlated to the effects of the process variables
on sol formation and gelation, providing insights related to the mechanisms involved. The influence of temperature of aluminum
isopropoxide hydrolysis on peptization and gelation of the mixtures was noted. The different behavior of mixtures hydrolyzed
at low and high temperatures was suggested to be caused by different mechanisms of surface charge formation on the structurally
different aluminum hydroxides. Monophasic and diphasic mullite xerogels were produced by changing temperature of aluminum
isopropoxide hydrolysis, and led to formation of mullite and Al−Si spinel phases respectively, when treated at 1100°C. 相似文献
157.
María del Carmen Barral Rodrigo González-Prieto Santiago Herrero Reyes Jiménez-Aparicio José Luis Priego Elia del Carmen Royer María Rosario Torres Francisco Alejandro Urbanos Felix Zamora 《Journal of Cluster Science》2008,19(1):219-230
Two new complexes, based on the unit Ru2Cl(μ-O2CC4H4N)4 (1) (O2CC4H4N = pyrrole-2-carboxylate), Ru2Cl(μ-O2CC4H4N)4(H2O)·4H2O [1(H
2
O)·4H
2
O], and Ru2Cl(μ-O2CC4H4N)4(Me2CO) [1(Me
2
CO)], are synthesized and structurally characterized. The physical properties of these complexes are studied and compared with
those previously reported for Ru2Cl(μ-O2CC4H4N)4(thf)·thf·H2O [1(thf)·thf·H
2
O]. The nature of the solvent molecule bonded to the axial position of the dimetallic unit determines the supramolecular interactions
leading to different arrangements in the solid state. The presence of NH groups in the pyrrolic rings favours the existence
of hydrogen bond interactions that are present in the three complexes. In addition, complex 1(Me
2
CO) shows π–π stacking interactions through pyrrolic rings of different dimetallic units.
Dedicated to the memory of Prof. F. Albert Cotton. 相似文献
158.
159.
Enrico A. Rodrigo 《Physics letters. A》1981,84(8):411-414
It is well known that the Casimir Energy depends on the geometry of the conducting cavity. In this note, scalar Green's functions are used to determine the Casimir energy's dependence on terms bilinear in the extrinsic curvatures of the cavity's surface, and thus to resolve the controversy over the Casimir energy's finiteness. 相似文献
160.
J. L. Bailly W. Bartl F. Bruyant W. M. Bugg C. Caso R. Contri H. Dibon R. Di Marco B. Epp A. Ferrando F. Fontanelli P. Girtler A. Gurfu E. L. Hart P. Herquet J. Hrubec Y. Iga E. Kisteney S. Kitamura J. M. Kohli H. Kohno J. C. Marin M. Markytan I. S. Mittra L. Montanet G. Neuhofer Y. Petrovykh R. Plano B. Poljakov P. Porth B. Powell B. Pylgroms T. Rodrigo A. H. Rogers J. Salicio S. Squarcia P. Stamer V. Stopchenko K. Sudhakar U. Trevisan C. Willmott T. Yamagata V. Yarba EHS-RCBC Collaboration Bombay-CERN-Genova-Innsbruck-Japan UG-Madrid-Mons-Rutgers-Serpukhov-Tennessee-Vienna Collaboration 《Zeitschrift fur Physik C Particles and Fields》1984,22(2):119-124
The intermediate and forward gamma detectors of EHS are used to reconstructπ°'s produced by 360 GeV/cpp interactions in the Rapid Cycling Bubble Chamber (RCBC). Using thepp forwardbackward symmetry, the inclusiveπ° production cross section is obtainedσ π°=(132±11) mb. The averageπ° multiplicity is determined as a function of the charged particle multiplicity. The (1?x) dependence is given for differentp T regions. 相似文献
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