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131.
Nabil Absi Stéphane Dauzère-Pérès Safia Kedad-Sidhoum Bernard Penz Christophe Rapine 《European Journal of Operational Research》2013
This paper introduces new environmental constraints, namely carbon emission constraints, in multi-sourcing lot-sizing problems. These constraints aim at limiting the carbon emission per unit of product supplied with different modes. A mode corresponds to the combination of a production facility and a transportation mode and is characterized by its economical costs and its unitary carbon emission. Four types of constraints are proposed and analyzed in the single-item uncapacitated lot-sizing problem. The periodic case is shown to be polynomially solvable, while the cumulative, global and rolling cases are NP-hard. Perspectives to extend this work are discussed. 相似文献
132.
An R-module M is called principally quasi-injective if each R-hornomorphism from a principal submodule of M to M can be extended to an endomorphism of M. Many properties of principally injective rings and quasi-injective modules are extended to these modules. As one application, we show that, for a finite-dimensional quasi-injective module M in which every maximal uniform submodule is fully invariant, there is a bijection between the set of indecomposable summands of M and the maximal left ideals of the endomorphism ring of M Throughout this paper all rings R are associative with unity, and all modules are unital. We denote the Jacobson radical, the socle and the singular submodule of a module M by J(M), soc(M) and Z(M), respectively, and we write J(M) = J. The notation N ?ess M means that N is an essential submodule of M. 相似文献
133.
Ashraf Ghanem Mohammed Nabil Aboul-Enein Aida El-Azzouny Mohammed F. El-Behairy 《Journal of chromatography. A》2010,1217(7):1063-1074
The enantioselective resolution of a set of racemic acidic compounds such as non-steroidal anti-inflammatory drugs (NSAIDs) of the group arylpropionic acid derivatives is demonstrated. Thus, a set of lipases were screened and manipulated in either the esterification or hydrolysis mode for the enantioselective kinetic resolution of these racemates in non-standard organic solvents. The accurate determination of the enantiomeric excesses of both substrate and product during such reaction is demonstrated. This was based on the development of a direct and reliable enantioselective high performance liquid chromatography (HPLC) procedure for the simultaneous baseline separation of both substrate and product in one run without derivatization. This was achieved using the immobilized chiral stationary phase namely Chiralpak IB, a 3,5-dimethylphenylcarbamate derivative of cellulose (the immobilized version of Chiralcel OD) which proved to be versatile for the monitoring of the lipase-catalyzed kinetic resolution of racemates in non-standard organic solvents. 相似文献
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136.
Nabil M. Hassan Tetsuo Ishikawa Masahiro Hosoda Atsuyuki Sorimachi Shinji Tokonami Masahiro Fukushi Sarata K. Sahoo 《Journal of Radioanalytical and Nuclear Chemistry》2010,283(1):15-21
The specific activities of 238U, 232Th, and 40K in selected building materials used in Japan were measured using a high-purity germanium detector. The uranium and thorium concentrations were determined from same samples using inductively coupled plasma mass spectrometry. There was a good agreement between the measurement of uranium and thorium with both methods (R 2 = 0.94, and 0.97, respectively). Based on the specific activities, we have estimated some hazard indexes such as radium equivalent activities (Ra eq), external hazard index (H ex), internal hazard index (H in), annual gonadal equivalent dose (AGED), internal alpha dose, mass exhalation rate and emanation coefficient of radon. 相似文献
137.
Jumat Salimon Nadia Salih Emad Yousif Ayad Hameed Ayad Kreem 《Arabian Journal of Chemistry》2010,3(4):205-210
In the present study a new acridone derivatives were synthesized. The newly synthesized compounds were characterized by IR, NMR and C, H, N, S analyses. All newly synthesized compounds were screened for their antibacterial (Staphylococcus aureus, Streptococcus viridans and Escherichia coil) and antifungal (Gibberela, Cercospora arachidicola, Physolospora piricola and Fusarium oxysporum) studies. The results revealed that all synthesized compounds have a significant biological activity against the tested microorganisms. 相似文献
138.
Diego?CattaruzzaEmail author Nabil?Absi Dominique?Feillet 《Annals of Operations Research》2018,271(1):127-159
This paper presents a survey on the multi-trip vehicle routing problem (MTVRP) and on related routing problems where vehicles are allowed to perform multiple trips and corresponds to the article by Cattaruzza et al. (4OR 14(3):223–259, 2016). The first part of the paper focuses on the MTVRP. It gives an unified view on mathematical formulations and surveys exact and heuristic approaches. The paper continues with variants of the MTVRP and other families of routing problems where multiple trips are sometimes allowed. For the latter, it specially insists on the motivations for having multiple trips and the algorithmic consequences. The expected contribution of the survey is to give a comprehensive overview on a structural property of routing problems that has seen a strongly growing interest in the last few years and that has been investigated in very different areas of the routing literature. 相似文献
139.
The topic of improving the ability of quantum systems to retain non-local features and enhance the efficiency of quantum protocols continues. This study delves into the thermal investigation of quantum correlations and teleportation fidelity of a two-qubit teleported state using excess electrons in a coupled double quantum dots system as a quantum channel. The study employs three reliable quantum quantifiers to prospect the resourcefulness and non-classicality of the system. The findings suggest that preserving quantum correlations and optimizing teleportation fidelity require minimizing tunneling coupling and maximizing Coulomb interaction. The study has significant implications for quantum physics and its practical applications in quantum information processing. 相似文献
140.
Nabil H. Amin Gamil A. El-Shobaky Gehan A. Fagal 《Journal of Radioanalytical and Nuclear Chemistry》1994,177(2):211-218
Methanol conversion reaction was carried out in contact with a poorly crystalline -alumina pre-irradiated with different doses of -rays. The reaction was conducted at 140–440°C using a flow technique under atmospheric pressure. The results obtained revealed that -irradiation of Al2O3 resulted in drastic modifications of its activity and selectivity in methanol conversion reaction. The dose of 15 Mrad was sufficient to suppress completely the formation of dimethyl ether (DME) and stimulated the formation of methane, which started at 200°C instead of 300°C in the case of the unirradiated alumina specimen. However, the rate of CH4 formation was found to decrease as a function of the dose employed. When the dose reached 140 Mrad, DME was reproduced with a rate comparable to that measured for the unirradiated catalyst sample. These results permitted us to conclude that DME is produced on the weak acidic sites (Brönsted acidity of Al2O3) and is not necessarily an intermediate compound for methane formation that takes place directly from methanol on strong acidic sites (Lewis acidity). The doses of 15–75 Mrad expelled completely the Brönsted acidic sites from Al2O3 surface, and the doses above this limit brought about a transformation of Lewis acidic sites into Brönsted acidity that is responsible for dimethyl ether formation. This transformation occurs by the action of liberated water from the dehydration of methyl alcohol. 相似文献