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1.
We study the relationship between the Ferrers property and the notion of interval order in the context of valued relations.
Given a crisp preference structure without incomparability, the strict preference relation satisfies the Ferrers property
if and only if the associated weak preference relation does. These conditions characterize a total interval order. For valued
relations the Ferrers property can be written in two different and non-equivalent ways. In this work, we compare these properties
by finding the kind of completeness they imply. Moreover, we study whether they still characterize a valued total interval
orders. 相似文献
2.
3.
Laurent A. Baumes Dr. Mireia Buaki Sogo Pedro Montes‐Navajas Dr. Avelino Corma Prof. Dr. Hermenegildo Garcia Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(15):4489-4495
γ‐Hydroxybutyric acid (GHB), a colourless, odourless and tasteless chemical, has become one of the most dangerous illicit drugs of abuse today. At low doses, this drug is a central nervous system depressant that reduces anxiety and produces euphoria and relaxation, sedating the recipient. There is an urgent need for simple, easy‐to‐use sensors for GHB in solution. Here, we present a colorimetric sensor array based on supramolecular host–guest complexes of fluorescent dyes with organic capsules (cucurbiturils) for the detection of GHB. 相似文献
4.
Amanda B. Lima Eric O. Faria Rodrigo H. O. Montes Rafael R. Cunha Eduardo M. Richter Rodrigo A. A. Munoz Wallans T. P. dos Santos 《Electroanalysis》2013,25(7):1585-1588
The electrochemical oxidation of ibuprofen at a boron‐doped diamond electrode (BDDE) and its voltammetric determination is reported for the first time. A well‐defined oxidation peak was observed at around 1.6 V in 0.1 mol L?1 H2SO4 solution with 10 % (v/v) ethanol at the BDDE surface activated by either cathodic or anodic pretreatments. A differential‐pulse voltammetric method for the determination of ibuprofen in pharmaceutical formulations was optimized with a detection limit of 5 µmol L?1 and compared with the British Pharmacopeia method. 相似文献
5.
Marcos V. dos S. Rezende Paulo J.R. Montes Mário E.G. Valerio 《Journal of luminescence》2012,132(5):1106-1111
The luminescence properties of Ce3+ in BaAl2O4 are reported. The results of simultaneous measurements of XEOL and XAS in the X-ray energy range that includes the Ba LII,III-edges and Ce LIII edge are shown. The XEOL yield increases as the energy of the photons increases. The radioluminescence spectra, taken from 200 to 1100 nm, showed broad emission bands corresponding to 5d1→2F5/2, 2F7/2 transitions of Ce3+ when incorporated into two nonequivalent Ba sites. The lifetime of the light emission was also measured using the single bunch operation mode at the Brazilian National Synchrotron Laboratory (LNLS), and BaAl2O4:Ce3+ showed single exponential decay time component of about 44.3 ns. 相似文献
6.
Alaitz Ruiz de Luzuriaga Irma Perez-Baena Sarah Montes Iraida Loinaz Ibon Odriozola Ignacio García José A. Pomposo 《Macromolecular Symposia》2010,296(1):303-310
A new route to functional polymeric nanoparticles (PNPs) of different chemical nature in the 3 to 20 nm size range is reported by combining both radical addition fragmentation chain transfer (RAFT) polymerization and “click” chemistry (CC) techniques. RAFT polymerization was employed for the synthesis of well-defined statistical copolymers with pending –Cl groups along the macromolecular chain. After transformation of the –Cl groups to –N3 groups by treatment with sodium azide, an appropriate bifunctional cross-linker is employed to obtain PNPs under CC conditions promoting intramolecular cycloaddition (cross-linking). Following this new route, polystyrene, poly(alkyl (meth)acrylate), polymethacrylic acid, poly(sodium styrenesulfonate) and poly(N-isopropyl) NPs have been synthesized and in-deep characterized. 相似文献
7.
Experience shows that static life tables overestimate death probabilities. As a consequence of this overestimation the premiums for annuities, pensions and life insurance are not what they actually should be, with negative effects for insurance companies or policy-holders. The reason for this overestimation is that static life tables, through being computed for a specific period of time, cannot take into account the decreasing mortality trend over time. Dynamic life tables overcome this problem by incorporating the influence of the calendar when graduating mortality. Recent papers on the topic look for the development of new methods to deal with this dynamism. 相似文献
8.
C. Bertoluzza V. Doldi J. Jimnez S. Montes 《International Journal of Approximate Reasoning》2008,48(2):481-498
Measuring the degree of non-adaptability of a partition to a criterion, represented by a reference partition, is an essential step in pseudo-questionnaires theory. In this work we characterize axiomatically the measure of non-adaptability in a general context. We base it on pre-orders on the set of all the possible experiences (complete or incomplete partitions). The construction of this measure is crucial for practical applications. It can be done in a natural way starting from the atoms of the partitions and constructing the non-adaptability measure by a process of successive aggregations made by suitable aggregation operators. 相似文献
9.
A problem of decision making under uncertainty in which the choice must be made between two sets of alternatives instead of two single ones is considered. A number of choice rules are proposed and their main properties are investigated, focusing particularly on the generalizations of stochastic dominance and statistical preference. The particular cases where imprecision is present in the utilities or in the beliefs associated to two alternatives are considered. 相似文献
10.
Susmita Bandyopadhyay Jose R. Peralta-Videa Jose A. Hernandez-Viezcas Milka O. Montes Arturo A. Keller Jorge L. Gardea-Torresdey 《应用光谱学评论》2013,48(3):180-206
Abstract: Currently, thousands of commercially available products contain engineered nanoparticles (ENPs). Because numerous nanoparticles (NPs) are being used in products that will be in contact with water or directly used in water treatment processes, these materials will undoubtedly reside, at least temporarily, in bodies of water. Given the widespread use of NPs and ENPs in consumer goods, a large portion of these materials will soon go into the waste stream, potentially to soil and sediments or added directly to agricultural lands via biosolids. Possible impacts of ENPs on aquatic and terrestrial ecosystems are of great concern. Preliminary data from several research groups have shown that ENPs may have a direct impact on food safety and the food chain. However, our knowledge about detection and characterization of NPs in the environment, especially aquatic environments, is still in its infancy. This review includes the most recent literature about the methods applied to the measurement of NPs and ENPs in the environment. The review covers methods to determine size distribution, shape, structure, surface charge, chemical composition, surface area, agglomeration, surface chemistry, porosity, and solubility. 相似文献