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861.
Examination of the ground-state correlation properties of two Coulombically interacting bosons confined in strongly anisotropic harmonic potentials is carried out within the framework of the single-mode approximation of the transverse components. The linear entropy of the quasi-one dimensional systems is discussed in dependence on the confinement anisotropy and the interaction strength. A comparison with a strictly one-dimensional limit is performed. 相似文献
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Marcin Sobczak Cezary Dębek Ewa Olędzka Grzegorz Nałęcz‐Jawecki Wacław L. Kołodziejski Maria Rajkiewicz 《Journal of polymer science. Part A, Polymer chemistry》2012,50(18):3904-3913
A series of biomedical polyurethane elastomers (PURs) based on poly(ester‐carbonate)s (PECs) and polycarbonates (PCs) were synthesized and spectrally characterized fully. PEC or PC diols were synthesized by the ring‐opening polymerization of ε‐caprolactone, trimethylene carbonate, and neopentyl carbonate catalyzed by lipase from Candida antarctica. PURs were prepared by free‐metal method from PEC or PC diols and 4,4′‐methylenebis(phenyl isocyanate), with 1,4‐butanediol as a chain extender. The physical and mechanical properties as well as hydrolytic stability of the obtained PURs were determined. The toxicity of the received polymers was evaluated using bacterial luminescence test and two protozoans assays. The presented preliminary studies suggest that PEC or PC diols prepared in this way might be applied for the synthesis of biomedical PURs with improved hydrolytic stability. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
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Renan Tunalıoğlu Çağrı Koç Tolga Bektaş 《The Journal of the Operational Research Society》2016,67(7):1012-1024
The process by which olive oil is produced yields two by-products, one of which is the brown-coloured Olive Oil Mill Wastewater (OMWW) and has no direct use. OMWW is generally disposed of into soil or rivers, potentially contaminating the environment. OMWW can be treated using ultrafiltration facilities, but this requires that OMWW is collected from oil mills and delivered to the treatment facilities using a fleet of vehicles in an economically viable manner. Such considerations give rise to a multiperiod location-routing problem. This paper formally introduces the problem and proposes an adaptive large neighbourhood search metaheuristic for its solution. The algorithm is applied on a case study drawn from one of the major olive oil producing countries. The paper presents computational and managerial results. 相似文献
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Wail Al Zoubi Min Jun Kim Abbas Ali Salih Al‐Hamdani Yang Gon Kim Young Gun Ko 《应用有机金属化学》2019,33(11)
Phosphorus‐based Schiff base were synthesized by treating bis{3‐[2‐(4‐amino‐1.5‐dimethyl‐2‐phenyl‐pyrazol‐3‐ylideneamino)ethyl]‐indol‐1‐ylmethyl}‐phosphinic acid with paraformaldehyde and characterized as a novel antioxidant. Its corresponding complexes [(VO)2L(SO4)2], [Ni2LCl4], [Co2LCl4], [Cu2LCl4], [Zn2LCl4], [Cd2LCl4], [Hg2LCl4], [Pd2LCl4], and [PtLCl]Cl2 were analyzed by Fourier transform‐infrared, (1H and 13C) nuclear magnetic resonance, and mass and UV–Vis spectroscopy. Experimental data showed that the ligand coordinated with the metal ions via donor atoms such as nitrogen to form an octahedral arrangement of the Schiff base around the central transition‐metal atom. The nature of these complexes was identified using the molar ratio and Job's methods, with the results agreeing with a metal‐to‐ligand (M:L) molar ratio of 2:1, expect for Pt, whose M:L was 1:1. Thermodynamic activation parameters such as ?E*, ?H*, ?S*, ?G*, and K were determined from the thermogravimetric analysis curve using the Coats–Redfern method. The antioxidant activities of the prepared compounds were assessed by using 1.1‐diphenyl‐2‐picrylhydrazyl as the free radical, and the results show that the complex Schiff bases were found to possess potent antioxidant activity. The structure–activity relationship of the ligand and its complexes indicates that the presence of electron‐donating moieties, such as Co(II) and Ni(II), in the chemical structure increases the antioxidant activity, whereas the Pt(IV) and Pd(II) complexes diminished the antioxidant activity, indicating the superior activity of the hydroxyl radical (OH·) over the superoxide radical. 相似文献