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61.
Amelia Bilbao-Terol Mar Arenas-Parra Verónica Cañal-Fernández Celia Bilbao-Terol 《Annals of Operations Research》2016,247(2):549-580
The current economic crisis fuels the financial social responsibility after an epoch of many excesses with damaging effects. This work tackles two emerging streams in the financial literature: the behavioral portfolio theory with mental accounting and the socially responsible investment (SRI). Promoting SRI is regarded by a lot of financial experts, policymakers and researchers from the field of economic and social sciences, as one of the potential solutions in order to avoid future crises. Therefore, new models for this investment approach are necessary. We try to support the class of investors that select their investments under a mental accounting framework and also they want to achieve a certain level of SR quality in their portfolios. In order to reconcile the two choice frames, avoiding unnecessary sacrifices in financial performance, we have designed a model based on goal programming that integrates the two cornerstones of the investor. Furthermore, we propose a fuzzy inference system to determine the amount of money allocated to each mental account as well as the confidence level assigned to each mental account. This tool is based on expert knowledge modeled by fuzzy if–then rules. 相似文献
62.
Teso Vilar E García Fraile A de la Moya Cerero S Martínez-Ruiz P Moreno Jiménez F 《Rapid communications in mass spectrometry : RCM》2011,25(3):395-409
The electron ionization (EI) mass spectra of a series of bridgehead-substituted 3,3-dimethylnorbornan-2-ones, derived from natural (1R)-(+)-camphor, have been studied and their cleavage mechanisms rationalized on the basis of the substituent shifts as well as on the identification of relevant peaks through accurate mass measurements and collision-induced dissociation (CID) tandem mass spectrometric experiments. The fragmentation patterns are very dependent on both the structural nature and the electronic properties of the bridgehead substituent. The driving force for the main fragmentation pathways are competitive cleavages of the C(1)-C(2) and C(2)-C(3) bonds directed by the bridgehead substituent and either the gem-dimethyl or carbonyl groups. These cleavages lead to distonic ions in which the charge is preferentially located either at the C(1), C(2) or C(3) positions depending on the electronic character and structural nature of the bridgehead substituent. This charge distribution determines the subsequent rearrangements and fragmentations. 相似文献
63.
Two new compounds in the Ca—Cu—Cd system of nominal composition Ca5Cu2Cd and Ca2Cu2Cd9 are synthesized from nearly stoichiometric mixtures of the elements (1100 °C, 48 h). 相似文献
64.
Ray AW Taatjes CA Welz O Osborn DL Meloni G 《The journal of physical chemistry. A》2012,116(25):6720-6730
Earlier synchrotron photoionization mass spectrometry experiments suggested a prominent ring-opening channel in the OH-initiated oxidation of cyclohexene, based on comparison of product photoionization spectra with calculated spectra of possible isomers. The present work re-examines the OH + cyclohexene reaction, measuring the isomeric products of OH-initiated oxidation of partially and fully deuterated cyclohexene. In particular, the directly measured photoionization spectrum of 2-cyclohexen-1-ol differs substantially from the previously calculated Franck-Condon envelope, and the product spectrum can be fit with no contribution from ring-opening. Measurements of H(2)O(2) photolysis in the presence of C(6)D(10) establish that the addition-elimination product incorporates the hydrogen atom from the hydroxyl radical reactant and loses a hydrogen (a D atom in this case) from the ring. Investigation of OH + cyclohexene-4,4,5,5-d(4) confirms this result and allows mass discrimination of different abstraction pathways. Products of 2-hydroxycyclohexyl-d(10) reaction with O(2) are observed upon adding a large excess of O(2) to the OH + C(6)D(10) system. 相似文献
65.
Castro-Ochoa D Peña-Montes C González-Canto A Alva-Gasca A Esquivel-Bautista R Navarro-Ocaña A Farrés A 《Applied biochemistry and biotechnology》2012,166(5):1275-1290
Cutinases are versatile carboxylic ester hydrolases with great potential in many biocatalytic processes, including biodiesel
production. Genome sequence analysis of the model organism Aspergillus nidulans reveals four genes encoding putative cutinases. In this work, we purified and identified for the first time a cutinase (ANCUT2)
produced by A. nidulans. ANCUT2 is a 29-kDa protein which consists of 255 amino acid residues. Comparison of the amino acid sequence of ANCUT2 with
other microbial cutinase sequences revealed a high degree of homology with other fungal cutinases as well as new features,
which include a serine-rich region and conserved cysteines. Cutinase production with different lipidic and carbon sources
was also explored. Enzyme activity was induced by olive oil and some triacylglycerides and fatty acids, whereas it was repressed
by glucose (1%) and other sugars. In some conditions, a 22-kDa post-translational processing product was also detected. The
cutinase nature of the enzyme was confirmed after degradation of apple cutin. 相似文献
66.
A McAnaw M Elena Lopez G Scott D Ellis D McKay GM Rosair AJ Welch 《Dalton transactions (Cambridge, England : 2003)》2012,41(36):10957-10969
Reduction of the tethered carborane 1,2-μ-(CH(2)SiMe(2)CH(2))-1,2-closo-C(2)B(10)H(10) followed by metallation with {CpCo} or {(p-cymene)Ru} fragments affords both C,C'-dimethyl 4,1,2-MC(2)B(10) and 4,1,6-MC(2)B(10) species. DFT calculations indicate that the barriers to isomerisation of both 4-Cp-4,1,2-closo-CoC(2)B(10)H(12) and 4-(η-C(6)H(6))-4,1,2-closo-RuC(2)B(10)H(12) to their respective 4,1,6-isomers are too high for this to be the origin of the unexpected formation of 4,1,6-MC(2)B(10) products (in marked contrast to the related isomerisation of 1,2-closo-C(2)B(11)H(13) to 1,6-closo-C(2)B(11)H(13)), and, indeed, the 4,1,2-species are recovered unchanged from refluxing toluene. Equally, the DFT-calculated profile for the isomerisation of [7,8-nido-C(2)B(10)H(12)](2-) to [7,9-nido-C(2)B(10)H(12)](2-) suggests that the unexpected formation of 4,1,6-metallacarboranes is unlikely to result from isomerisation of a reduced (nido) carborane following desilylation. Instead, the source of the 4,1,6-MC(2)B(10) compounds is traced to desilylation of 1,2-μ-(CH(2)SiMe(2)CH(2))-1,2-closo-C(2)B(10)H(10) by Li or Na prior to reduction. The supraicosahedral metallacarboranes 1,8-Me(2)-4-Cp-4,1,8-closo-CoC(2)B(10)H(10), 1,12-Me(2)-4-Cp-4,1,12-closo-CoC(2)B(10)H(10) and 1,12-Me(2)-4-(p-cymene)-4,1,12-closo-RuC(2)B(10)H(10) are also reported with all new species characterised both spectroscopically and crystallographically. 相似文献
67.
PC Andrews M Busse GB Deacon RL Ferrero PC Junk JG Maclellan A Vom 《Dalton transactions (Cambridge, England : 2003)》2012,41(38):11798-11806
Four new tris-substituted bismuth(iii) sulfonates of general formula [Bi(O(3)SR)(3)] (R = phenyl 1, p-tolyl 2, 2,4,6-mesityl 3 and S-(+)-10-camphoryl 4) have been synthesised and characterised. Their synthesis by solvent-free (SF) and solvent-mediated (SM) methods has been explored and their activity against Helicobacter pylori has been investigated. The compounds 1-4 display a remarkable in vitro activity against three laboratory strains of H. pylori (B128, 26?695 and 251) with minimum inhibitory concentration (MIC) values as low as 0.049 μg mL(-1) for the strains B128 and 26?695, and 0.781 μg mL(-1) for the clinical isolate 251. This places most MIC values in the nano-molar region and demonstrates the strong influence of the sulfonate group on the bactericidal properties. The novel solid state structure [Bi(8)(O(3)SMes)(20)(SO(4))(2)(H(2)O)(6)]·(C(7)H(8))(7)5·(C(7)H(8))(7), derived from the SM reaction under reflux conditions, is presented and the incorporation of the two inorganic sulfate anions in the centre of the wheel-like bismuth sulfonate cluster explained. 相似文献
68.
Amelia Carolina Sparavigna 《Phase Transitions》2013,86(8):620-631
We present a polarizing optical microscopy study of a liquid-crystal mixture of trans-4-hexylcyclohexanecarboxilic (C6) and benzoic acids. Both materials have carboxylic groups that can form dimers through hydrogen bonding. The mixture is nematic at room temperature and has the clearing point at 88°C. The nematic phase shows ringed spherulites, sometimes looking like spiral structures, and undulated textures, which remain visible when heating the sample till 71°C. This is the temperature of a texture transition inside the nematic phase. 相似文献
69.
Antonio Di Crescenzo Virginia Giorno Balasubramanian Krishna Kumar Amelia G. Nobile 《Methodology and Computing in Applied Probability》2012,14(4):937-954
Consider a system performing a continuous-time random walk on the integers, subject to catastrophes occurring at constant rate, and followed by exponentially-distributed repair times. After any repair the system starts anew from state zero. We study both the transient and steady-state probability laws of the stochastic process that describes the state of the system. We then derive a heavy-traffic approximation to the model that yields a jump-diffusion process. The latter is equivalent to a Wiener process subject to randomly occurring jumps, whose probability law is obtained. The goodness of the approximation is finally discussed. 相似文献
70.
J.M. Alonso-Meijide J.M. Bilbao B. Casas-Méndez J.R. Fernández 《European Journal of Operational Research》2009
An a priori system of unions or coalition structure is a partition of a finite set of players into disjoint coalitions which have made a prior commitment to cooperate in playing a game. This paper provides “ready-to-apply” procedures based on generating functions that are easily implementable to compute coalitional power indices in weighted multiple majority games. As an application of the proposed procedures, we calculate and compare coalitional power indices under the decision rules prescribed by the Treaty of Nice and the new rules proposed by the Council of the European Union. 相似文献