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1.
M I Salema A P B Póvoa A Q Novais 《The Journal of the Operational Research Society》2006,57(6):615-629
In this paper, an MILP formulation is proposed for the design of a reverse logistics network based on a warehouse location–allocation model, which optimizes, simultaneously, the forward and reverse networks. A single product model with unlimited capacity is first defined. Subsequently, the model is extended to a multi-product capacitated recovery network model, where capacity limitations and a multi-product system can be considered. The proposed model is compared to published work in the field, where different model assumptions have been proposed. Two cases are described so as to gain a better insight into the model and allow a comparative analysis. 相似文献
2.
Fernandes-Ferreira M. Pais M. Salomé S. Novais J. M. 《Applied biochemistry and biotechnology》1991,28(1):169-181
Applied Biochemistry and Biotechnology - Micropropagated Euphorbia characias plants gave higher yields of crude oil than did wild ones. Leaves of either wild and micropropagated plants contained... 相似文献
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Leandro F. Pedrosa William P. de Macedo Antonia C. R. Furtado Guilherme P. Guedes Luiz C. S. Pinheiro Jackson A. L. C. Resende 《合成通讯》2013,43(24):3373-3386
New thieno[2,3-b]pyridine phosphoramidates compounds were synthesized and characterized by infrared; 1H, 13C, and 31P NMR spectroscopy; and high-resolution mass spectrometry. The products were obtained in good yields (64–82%) under mild conditions by nucleophilic aromatic substitution reaction of aminoalkylphosphoramidates over 4-chlorothieno[2,3-b]pyridine-5-carbonitrile. The crystal structures of two compounds were solved by x-ray diffraction and showed a network of intermolecular interactions involving phosphoramidate groups. Druglike properties and toxicity of the new compounds were studied with the help of the software Molinspiration, Osiris, and Toxtree, and were compared with the standard drugs amphotericin B, miltefosine, benznidazole, and nifurtimox. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.] 相似文献
6.
Ana Elisa Ferreira Oliveira Arnaldo César Pereira Mayra Asevedo Campos de Resende Lucas Franco Ferreira 《Electroanalysis》2022,34(5):809-819
In this work, a silver/silver chloride ink is fabricated using two steps. First the silver ink is prepare using silver, nail polish and acetone. Then the silver ink is painted in a paper substrate and a silver chloride layer is deposited using a bleach solution. The result is the silver/silver chloride conductive ink. The silver ink is cheap ($2.49/g), well-dispersive and very easy to fabricate. The materials were characterized by SEM and XRD. The Ag ink showed the formation of a continuous network throughout the silver ink film with fewer agglomeration. The effective chlorination process was also observed in the Ag/AgCl characterization. Since the Ag/AgCl substrate will be used as a quasi-reference electrode, it is important to investigate the electrical properties. The Ag ink showed an average ohmic resistance of 2.27 Ω. The addition of the AgCl layer decreases the conductivity, as expected. In summary, the Ag/Ag/Cl ink developed is simple, well-dispersed, cheap and with good conductivity. Therefore, it can be used as a conductive ink in the fabrication of quasi-reference electrodes. 相似文献
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Duarte Valdyster Shirley Santos Rodrigues Aldimar Machado de Andrade-Filho Tarciso Silva Souza Divanizia do Nascimento de Novais Erico Raimundo Pereira Novais Andréa de Lima Ferreira de Oliveira Glaura Caroena Azevedo 《Structural chemistry》2021,32(4):1589-1595
Structural Chemistry - We investigatethe electronic and structural properties of two new amorphous materials, Bi6Ca2O28B12 and Bi6Ca2 O28B11:Tm, using density functional theory with a short-range... 相似文献
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We analyze the problem of a quantum computer in a correlated environment protected from decoherence by quantum error correction using a perturbative renormalization group approach. The scaling equation obtained reflects the competition between the dimension of the computer and the scaling dimension of the correlations. For an irrelevant flow, the error probability is reduced to a stochastic form for a long time and/or a large number of qubits; thus, the traditional derivation of the threshold theorem holds for these error models. In this way, the "threshold theorem" of quantum computing is rephrased as a dimensional criterion. 相似文献
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The phase diagram of a dissipative particle in a periodic potential and a magnetic field is studied in the weak barrier limit and in the tight binding regime. For the case of half flux per plaquette, and for a wide range of values of the dissipation, the physics of the model is determined by a nontrivial fixed point. A combination of exact and variational results is used to characterize this fixed point. Finally, it is also argued that there is an intermediate energy scale that separates the weak coupling physics from the tight binding solution. 相似文献
10.
Rui M. Novais Frank Simon Petra Pötschke Tobias Villmow José A. Covas Maria C. Paiva 《Journal of polymer science. Part A, Polymer chemistry》2013,51(17):3740-3750
This work reports the study of the effect of chemical functionalization of carbon nanotubes on their dispersion in poly(lactic acid). The nanotubes were functionalized by the 1,3‐dipolar cycloaddition reaction, generating pyrrolidine groups at the nanotube surface. Further reaction of the pyrrolidine groups with poly(lactic acid) was studied in solution and in the polymer melt. The former involved refluxing the nanotubes in a dimethylformamide/polymer solution; the latter was carried out by direct melt mixing in a microcompounder. The carbon nanotubes collected after each process were characterized by thermogravimetry and by X‐ray photoelectron spectroscopy, showing evidence of polymer bonded to the nanotube surface only when the reaction was carried out in the polymer melt. The composites with polymer modified nanotubes present smaller average agglomerate area and a narrower agglomerate area distribution. In addition, they show improved tensile properties at low CNT concentration and present lower electrical resistivity. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 3740–3750 相似文献