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41.
Positive evidence for cold nuclear fusion in an electrochemical cell with a palladium thin foil cathode was obtained. After adding thiourea to the cell, seven successive emissions of neutrons (detected as thermal neutrons) alternating with inactive periods were registered. The maximum intensity (300 times the background) and duration (12.7 h) were attained in the fifth emission. 相似文献
42.
Patricia A.M. Williams Evelina G. Ferrer Karina A. Pasquevich Enrique J. Baran Eduardo E. Castellano Oscar E. Piro 《Journal of chemical crystallography》2000,30(8):539-544
The crystal and molecular structure of the title compound, for short [Fe(o-phen)3](sac)2·(Hsac)·6H2O, has been determined by X-ray diffraction methods. It crystallizes in the monoclinic space group P21/n with a = 16.3190(1), b = 19.2890(1), c = 17.4490(2) Å, = 92.586(1)°, V = 5486.95(8) Å3 and, Z = 4. The investigated compound constitutes the first example of a species in which uncoordinated saccharin and saccharinate anions are present in the structure. The crystallographic results reveal the subtle differences between the structure of the neutral molecule and its anion. The complex was also characterized by means of infrared, electronic, and 57Fe-Mössbauer spectroscopy. Its magnetic susceptibility was determined at room temperature and its thermal behavior investigated by means of thermogravimetric and differential thermal analytical techniques. 相似文献
43.
Boris A. Arbuzov Elena Ya. Zabotina Evelina N. Dianova Igor A. Litvinov Victor A. Naumov Shamil K. Latypov Ahat V. Il'asov 《Heteroatom Chemistry》1992,3(2):151-156
5-Methyl-2-phenyl-2H- 1,2,3-diazaarsole 1 reacts with ethyl diazoacetate to form a 1:1 bicyclic product 3a , 8-ethoxycarbonyl-4-methyl-2-phenyl-1-arsa-2,3,6,7-tetraazabicyclo[3.3.0]octa-3.7-diene. The latter isomerizes to a two-coordinate arsenic compound 5 , 3-ethoxycarbonyl-5-[α-(phenylhydrazono)ethyl] 1-1,2,4-diazaarsole. The X-ray crystal structure analyses of both products 3a and 5 have been carried out. 相似文献
44.
Laville L Charnay C Lamaty F Martinez J Colacino E 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(3):760-764
Underwater exploration: The ring-closing metathesis of N,N-diallyltosylamine (DATs) and diallyldiethyl malonate has been studied in aqueous micellar medium, at room temperature, in the presence of four different gemini cationic surfactants and various ruthenium catalysts. For the first time, the adsorption mechanisms and the reaction steps involved in this heterogeneous catalytic process were elucidated. 相似文献
45.
Ferrer EG Gómez AV Añón MC Puppo MC 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,79(1):278-281
Food protein product, gluten protein, was chemically modified by varying levels of sodium stearoyl lactylate (SSL); and the extent of modifications (secondary and tertiary structures) of this protein was analyzed by using Raman spectroscopy. Analysis of the Amide I band showed an increase in its intensity mainly after the addition of the 0.25% of SSL to wheat flour to produced modified gluten protein, pointing the formation of a more ordered structure. Side chain vibrations also confirmed the observed changes. 相似文献
46.
Evelina A. Velcheva Bistra A. Stamboliyska Pavlina J. Boyadjieva 《Journal of Molecular Structure》2010,963(1):57-62
The structure of o-vanillin molecule and its oxyanion have been studied by density functional theory (DFT), employing the B3LYP functional and 6-311++G** basis set. All conformational isomers of o-vanillin and of its anion have been located and their relative energies have been determined. The IR spectral changes, caused by the conversion of the molecule into the corresponding oxyanion have been studied. In a general agreement between theory and experiment, the conversion causes a frequency decrease of the carbonyl stretching band ν(CO) and essential intensity increases of the aromatic skeletal bands as well as methyl stretching band ν(CH3). According to the NBO electric charge analysis, the oxyanionic center bears 60% of the whole anionic net charge. 相似文献
47.
We obtain upper and lower Gaussian density estimates for the laws of each component of the solution to a one-dimensional fully coupled forward-backward SDE. Our approach relies on the link between FBSDEs and quasilinear parabolic PDEs, and is fully based on the use of classical results on PDEs rather than on manipulation of FBSDEs, compared to other papers on this topic. This essentially simplifies the analysis. 相似文献
48.
Patricia A. M. Williams Evelina G. Ferrer Natalia Baeza Oscar E. Piro Enrique J. Baran Prof. Dr. 《无机化学与普通化学杂志》2006,632(4):619-623
Two new saccharinate/NH3 complexes of composition [Ni(sac)2(NH3)4] and [Zn(sac)2(NH3)2] were obtained and their crystal structures determined by single crystal X‐ray diffractometry. The elongated octahedral NiII complex crystallizes in the monoclinic P21/c space group with Z = 2 whereas the tetrahedral ZnII complex is triclinic (space group and Z = 2). For [Ni(sac)2(NH3)4] the magnetic moment and electron absorption spectrum were obtained and discussed. The infrared spectra of both complexes were also recorded and briefly commented. 相似文献
49.
Marco Alberti Marco Gavanelli Evelina Lamma Paola Mello Paolo Torroni Giovanni Sartor 《Computational & Mathematical Organization Theory》2006,12(2-3):205-225
Deontic concepts and operators have been widely used in several fields where representation of norms is needed, including
legal reasoning and normative multi-agent systems.
The EU-funded SOCS project has provided a language to specify the agent interaction in open multi-agent systems. The language
is equipped with a declarative semantics based on abductive logic programming, and an operational semantics consisting of
a (sound and complete) abductive proof procedure. In the SOCS framework, the specification is used directly as a program for
the verification procedure.
In this paper, we propose a mapping of the usual deontic operators (obligations, prohibition, permission) to language entities,
called expectations, available in the SOCS social framework. Although expectations and deontic operators can be quite different
from a philosophical viewpoint, we support our mapping by showing a similarity between the abductive semantics for expectations
and the Kripke semantics that can be given to deontic operators.
The main purpose of this work is to make the computational machinery from the SOCS social framework available for the specification
and verification of systems by means of deontic operators.
Marco Alberti received his laurea degree in Electronic Engineering in 2001 and his Ph.D. in Information Engineering in 2005 from the University
of Ferrara, Italy. His research interests include constraint logic programming and abductive logic programming, applied in
particular to the specification and verification of multi-agent systems. He has been involved as a research assistants in
national and European research projects. He currently has a post-doc position in the Department of Engineering at the University
of Ferrara.
Marco Gavanelli is currently assistant professor in the Department of Engineering at the University of Ferrara, Italy. He graduated in Computer
Science Engineering in 1998 at the University of Bologna, Italy. He got his Ph.D. in 2002 at Ferrara University. His research
interest include Artificial Intelligence, Constraint Logic Programming, Multi-criteria Optimisation, Abductive Logic Programming,
Multi-Agent Systems. He is a member of ALP (the Association for Logic Programming) and AI*IA (the Italian Association for
Artificial Intelligence). He has organised workshops, and is author of more than 30 publications between journals and conference
proceedings.
Evelina Lamma received her degree in Electronic Engineering from University of Bologna, Italy, in 1985 and her Ph.D. degree in Computer
Science in 1990. Currently she is Full Professor at the Faculty of Engineering of the University of Ferrara where she teaches
Artificial Intelligence and Foundations of Computer Science. Her research activity focuses around:
– programming languages (logic languages, modular and object-oriented programming);
– artificial intelligence;
– knowledge representation;
– intelligent agents and multi-agent systems;
– machine learning.
Her research has covered implementation, application and theoretical aspects. She took part to several national and international
research projects. She was responsible of the research group at the Dipartimento di Ingegneria of the University of Ferrara
in the UE ITS-2001-32530 Project (named SOCS), in the the context of the UE V Framework Programme - Global Computing Action.
Paola Mello received her degree in Electronic Engineering from the University of Bologna, Italy, in 1982, and her Ph.D. degree in Computer
Science in 1989. Since 1994 she has been Full Professor. She is enrolled, at present, at the Faculty of Engineering of the
University of Bologna (Italy), where she teaches Artificial Intelligence. Her research activity focuses on programming languages,
with particular reference to logic languages and their extensions, artificial intelligence, knowledge representation, expert
systems with particular emphasis on medical applications, and multi-agent systems. Her research has covered implementation,
application and theoretical aspects and is presented in several national and international publications. She took part to
several national and international research projects in the context of computational logic.
Giovanni Sartor is Marie-Curie professor of Legal informatics and Legal Theory at the European University Institute of Florence and professor
of Computer and Law at the University of Bologna (on leave), after obtaining a PhD at the European University Institute (Florence),
working at the Court of Justice of the European Union (Luxembourg), being a researcher at the Italian National Council of
Research (ITTIG, Florence), and holding the chair in Jurisprudence at Queen’s University of Belfast (where he now is honorary
professor). He is co-editor of the Artificial Intelligence and Law Journal and has published widely in legal philosophy, computational
logic, legislation technique, and computer law.
Paolo Torroni is Assistant Professor in computing at the Faculty of Engineering of the University of Bologna, Italy. He obtained a PhD
in Computer Science and Electronic Engineering in 2002, with a dissertation on logic-based agent reasoning and interaction.
His research interests mainly focus on computational logic and multi-agent systems research, including logic programming,
abductive and hypothetical reasoning, agent interaction, dialogue, negotiation, and argumentation. He is in the steering committee
of the CLIMA and DALT international workshops and of the Italian logic programming interest group GULP. 相似文献
50.
Determining discrete time-cost tradeoffs in project networks allows for the control of the processing time of an activity
via the amount of non-renewable resources allocated to it. Larger resource allocations with associated higher costs reduce
activities’ durations. Given a set of execution modes (time-cost pairs) for each activity, the discrete time-cost tradeoff
problem (DTCTP) involves selecting a mode for each activity so that either: (i) the project completion time is minimized,
given a budget, or (ii) the total project cost is minimized, given a deadline, or (iii) the complete and efficient project
cost curve is constructed over all feasible project durations. The DTCTP is a problem with great applicability prospects but
at the same time a strongly N P{\mathcal N}\,P-hard optimization problem; solving it exactly has been a real challenge. Known optimal solution methodologies are limited
to networks with no more than 50 activities and only lower bounds can be computed for larger, realistically sized, project
instances. In this paper, we study a path-based approach to the DTCTP, in which a new path-based formulation in activity-on-node
project networks is presented. This formulation is subsequently solved using an exact cutting plane algorithm enhanced with
speed-up techniques. Extensive computational results reported for almost 5,000 benchmark test problems demonstrate the effectiveness
of the proposed algorithm in solving to optimality for the first time some of the hardest and largest instances in the literature.
The promising results suggest that the algorithms may be embedded into project management software and, hence, become a useful
tool for practitioners in the future. 相似文献