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41.
This paper considers the pricing decisions of substitutable products which are produced by duopolistic manufacturers respectively and then sold by one common retailer to the consumers. Both the manufacturing cost and the customer demand for each product are characterized as fuzzy variables. Six expected value models are developed to explore the effects of the duopolistic manufacturers’ three pricing strategies (i.e. Bertrand competition, Stackelberg competition, cooperation) and vertical competition between the manufacturers and the retailer on the optimal pricing decisions and channel profit-split of a two echelon supply chain, and the corresponding analytical solutions are derived. Finally, a numerical example is given to illustrate the effectiveness of the proposed models, and to gain additional managerial insights. 相似文献
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Dmitry M. Rein Liron Shavit Rafail L. Khalfin Yachin Cohen Ann Terry Sanjay Rastogi 《Journal of Polymer Science.Polymer Physics》2004,42(1):53-59
The effect of pressure on phase transformations of ultradrawn ultra-high-molecular-weight polyethylene (UHMWPE) fibers was examined by in situ X-ray diffraction measurements with synchrotron radiation. The mesomorphic hexagonal phase was metastable even at a relatively low pressure of about 100 bar. The effect of pressure on the melting transitions was larger than in chain-folded structures. The existence and metastability of the hexagonal phase is the basis of compaction technology of UHMWPE fibers in composite materials. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 53–59, 2004 相似文献
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(-)-Quinocarcin (1) has been synthesized in a longest linear sequence of 22 steps from 3-hydroxybenzaldehyde in 16% overall yield. The Pictet-Spengler reaction of L-tert-butyl-2-bromo-5-hydroxy phenylalanate (17), synthesized according to Corey-Lygo's enantioselective alkylation process, with benzoxyacetaldehyde (12) under mild acidic conditions afforded 1,3-cis tetrahydroisoquinoline 20 as an only isolable stereomer in 91% yield. The diazabicycle[3,2,1]-octane ring system of 28 was constructed by a silver tetrafluoroborate-promoted intramolecular Mannich reaction using amino thioether as a latent N-acyliminium species and tethered silyl enol ether as a nucleophile. Using amino thioether instead of aminal as a precursor of N-acyliminium was of high importance to the success of this otherwise disfavored 5-endo-Trig cyclization. A Hf(OTf)4-catalyzed (0.1 equiv) transformation of aminal to amino thioether was uncovered in the course of this study, allowing the conversion of tricyclic aminal 24 to amino thioether 25 to be realized in high yield. From the bridged tetracyclic compound 28, a sequence of oxidation of aldehyde to acid, global deprotection under hydrogenolysis conditions, and one-pot partial reduction of lactam to aminal/oxazolidine formation completed the total synthesis of the pentacyclic (-)-quinocarcine. 相似文献
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Lavert-Ofir E David L Henson AB Gersten S Narevicius J Narevicius E 《Physical chemistry chemical physics : PCCP》2011,13(42):18948-18953
The long standing goal of chemical physics is finding a convenient method to create slow and cold beams intense enough to observe chemical reactions in the temperature range of a few Kelvin. We present an extensive numerical analysis of our moving magnetic trap decelerator showing that a 3D confinement throughout the deceleration process enables deceleration of almost all paramagnetic particles within the original supersonic expansion to stopping velocities. We show that the phase space region containing the decelerating species is larger by two orders of magnitude as compared to other available deceleration methods. 相似文献
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Back Cover: Dormant versus Evolving Aminopalladated Intermediates: Toward a Unified Mechanistic Scenario in PdII‐Catalyzed Aminations (Chem. Eur. J. 6/2014) 下载免费PDF全文
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Philosof-Mazor L Volinsky R Comin MJ Lewin NE Kedei N Blumberg PM Marquez VE Jelinek R 《Langmuir : the ACS journal of surfaces and colloids》2008,24(19):11043-11052
Synthetic diacylglycerol lactones (DAG-lactones) have been shown to be effective modulators of critical cellular signaling pathways. The biological activity of these amphiphilic molecules depends in part upon their lipid interactions within the cellular plasma membrane. This study explores the thermodynamic and structural features of DAG-lactone derivatives and their lipid interactions at the air/water interface. Surface-pressure/area isotherms and Brewster angle microscopy revealed the significance of specific side-groups attached to the terminus of a very rigid 4-(2-phenylethynyl)benzoyl chain of the DAG-lactones, which affected both the self-assembly of the molecules and their interactions with phospholipids. The experimental data highlight the formation of different phases within mixed DAG-lactone/phospholipid monolayers and underscore the relationship between the two components in binary mixtures of different mole ratios. Importantly, the results suggest that DAG-lactones are predominantly incorporated within fluid phospholipid phases rather than in the condensed phases that form, for example, by cholesterol. Moreover, the size and charge of the phospholipid headgroups do not seem to affect DAG-lactone interactions with lipids. 相似文献
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Giboulot S Liron F Prestat G Wahl B Sauthier M Castanet Y Mortreux A Poli G 《Chemical communications (Cambridge, England)》2012,48(47):5889-5891
In the presence of an allyl alcohol, α-chloroacetophenones undergo an allyloxycarbonylation reaction followed by in situ decarboxylative allylation to selectively afford the corresponding monoallylated ketones via a Pd-catalyzed domino sequence. The scope of the reaction was extended to substituted α-chloroacetophenones as well as various allyl alcohols. 相似文献