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81.
M. Koppe M. Scharber C. Brabec W. Duffy M. Heeney I. McCulloch 《Advanced functional materials》2007,17(8):1371-1376
Thiophene‐containing polymers blended with fullerenes have recently demonstrated impressively high photovoltaic efficiencies. One drawback of this class of polymers is their relatively low ionization potential, which leads to rather low open‐circuit voltages. Polyterthiophenes belong to a material class that has recently captured a large amount of interest for polymer electronic applications because of its excellent transport properties. Because of the slightly lower ionization potential, this material class appears more attractive for photovoltaic applications than polythiophenes. In this work, the photovoltaic performance of bulk heterojunction solar cells from polyterthiophene/fullerene composites is discussed and compared to the polymer/fullerene blend morphology. 相似文献
82.
Malcolm W.B. McCulloch 《Tetrahedron letters》2005,46(44):7619-7621
The first synthesis of the natural product guieranone A is described, demonstrating a one-pot procedure for the synthesis of protected-1,3,6,8-tetraoxygenated naphthalenes and a subsequent directed metalation synthesis of 2-keto naphthalenes. 相似文献
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R.A. McCulloch N.M. Clarke R.J. Griffiths J.S. Hanspal S. Roman J.M. Barnwell 《Nuclear Physics A》1984,431(2):344-366
Distributions of cross sections and analysing powers have been measured over the range ~ 14°–100° c.m. for the reactions at 33.4 MeV incident e using a ~ 95 % enriched 30Si target. Phenomenological optical-model analyses of the elastic-scattering data have been carried out. A DWBA analysis of the inelastic-scattering data for the 2.24 MeV (2+) and 5.49 MeV (3?) states of 30Si has yielded values of the deformation β2 and β3. The j-dependence of the analysing powers for the (3He, 4He) and (3He, 2H) reactions has identified the 6.71 MeV level of 29Si as a state, and a level near 9.5 MeV in 31P as a possible state. Spectroscopic factors for ten states in 29Si and seven states in 31P have been deduced and are compared with other work. The extent to which the data defines the 3He spin-orbit potential is discussed. 相似文献
85.
Iain A. Stewart 《Mathematical Logic Quarterly》1994,40(1):132-140
We investigate why similar extensions of first-order logic using operators (that is, generalized quantifiers) corresponding to NP-complete decision problems apparently differ in expressibility: the logics capture either NP or LNP. It had been conjectured that the complexity class captured is NP if and only if the operator is monotone. We show that this conjecture is false. However, we provide evidence supporting a revised conjecture involving finite variations of monotone problems. Mathematics Subject Classification: 68Q15, 03D15, 03C13. 相似文献
86.
Bhatt AI du Fou de Kerdaniel E Kinoshita H Livens FR May I Polovov IB Sharrad CA Volkovich VA Charnock JM Lewin RG 《Inorganic chemistry》2005,44(1):2-4
In situ EXAFS spectroscopic studies of uranium compounds in high temperature alkali chloride melts indicate the presence of oligomeric species. An investigation into UCl(3) and UCl(4) dissolved in LiCl reveals long range ordering of uranium atoms in the molten state which is not maintained on quenching. Studies of uranium dioxide dissolved in LiCl-KCl eutectic with HCl exhibit long range ordering in both molten and quenched states, and the EXAFS data can be modeled using multiple coordination shells. 相似文献
87.
Iain J McGaw 《Microscopy and microanalysis》2005,11(1):18-36
Historically, the decapod crustacean circulatory system has been classed as open. However, recent work on the blue crab, Callinectes sapidus, suggests the circulatory system may be more complex than previously described. Corrosion casting techniques were refined and used to map the circulatory system of a variety of crab species (order: Decapoda; family: Cancridae) to determine if the complexity observed in the blue crab was present in other species. Seven arteries arose from the single chambered heart. The anterior aorta, the paired anterolateral arteries, and the paired hepatic arteries exited from the anterior aspect of the heart. The small-diameter posterior aorta exited posteriorly from the heart. Exiting from the ventral surface of the heart, the sternal artery branched to supply the legs and mouthparts of the crab. These arteries were more complex than previously described, with arterioles perfusing all areas of the body. The arterioles split into fine capillary-like vessels. Most of these capillaries were blind ending. However, in several areas (antennal gland, supraesophageal ganglion) complete capillary beds were present. After passing through the capillary-like vessels, blood drained into a series of sinuses. However, rather than being arbitrary spaces as previously described, scanning electron micrographs showed the sinuses to be distinct units. Most of the sinuses formed a series of flattened membrane-bound lacunae. This complexity may qualify the decapod crustacean circulatory system as one that is "partially closed" rather than open. 相似文献
88.
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90.
Mpamhanga CP Chen B McLay IM Willett P 《Journal of chemical information and modeling》2006,46(2):686-698
A new method for the postprocessing of docking outputs has been developed, based on encoding putative 3D binding modes (docking solutions) as ligand-protein interactions into simple bit strings, a method analogous to the structural interaction fingerprint. Instead of employing traditional scoring functions, the method uses a series of new, knowledge-based scores derived from the similarity of the bit strings for each docking solution to that of a known reference binding mode. A GOLD docking study was carried out using the Bissantz estrogen receptor antagonist set along with the new scoring method. Superior recovery rates, with up to 2-fold enrichments, were observed when the new knowledge-based scoring was compared to the GOLD fitness score. In addition, top ranking sets of molecules (actives and potential actives or decoys) were structurally diverse with low molecular weights and structural complexities. Principal component analysis and clustering of the fingerprints permits the easy separation of active from inactive binding modes and the visualization of diverse binding modes. 相似文献