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91.
Gerhard Jany Timo Repo Marina Gustafsson Martti Klinga Adnan S. Abu‐Surrah Markku Leskel 《无机化学与普通化学杂志》2000,626(9):1897-1900
The synthesis and characterization of the unsymmetric hafnium dialkyl [1‐(η5‐9‐fluorenyl)‐2‐(η5‐1‐indenyl)ethane]HfCl2 ( 2 ) and corresponding dimethyl complex [1‐(η5‐9‐fluorenyl)‐2‐(η5‐1‐indenyl)ethane]Hf(CH3)2 ( 3 ) is described. The dialkyl hafnocene ( 3 ) crystallizes in monoclinic space group P21/c (No. 14) with a = 9.458(8), b = 8.541(8), c = 23.733(11) Å, β = 93.16(5) deg., V = 1914(3) Å3, Z = 4. Further on, complex 3 was activated with methylaluminiumoxane (MAO) and utilized as a catalyst in ethene polymerization. 相似文献
92.
Louhivuori M Otten R Lindorff-Larsen K Annila A 《Journal of the American Chemical Society》2006,128(13):4371-4376
The discovery of dilute liquid crystalline media to align biological macromolecules has opened many new possibilities to study protein and nucleic acid structures by NMR spectroscopy. We inspect the basic alignment phenomenon for an ensemble of protein conformations to deduce relative contributions of each member to the residual dipolar coupling signals. We find that molecular fluctuations can affect the alignment and discover a resulting emphasis of certain conformations. However, the internal fluctuations are largely uncorrelated with those of the alignment, implying that proteins have liquidlike molecular surfaces. Furthermore, we consider the implications of a dynamic bias to structure determination using data from the weak alignment method. 相似文献
93.
Amir Asadpoordarvish Andreas Sandström Christian Larsen Roger Bollström Martti Toivakka Ronald Österbacka Ludvig Edman 《Advanced functional materials》2015,25(21):3238-3245
A solution‐based fabrication of flexible and light‐weight light‐emitting devices on paper substrates is reported. Two different types of paper substrates are coated with a surface‐emitting light‐emitting electrochemical cell (LEC) device: a multilayer‐coated specialty paper with an intermediate surface roughness of 0.4 μm and a low‐end and low‐cost copy paper with a large surface roughness of 5 μm. The entire device fabrication is executed using a handheld airbrush, and it is notable that all of the constituent layers are deposited from solution under ambient air. The top‐emitting paper‐LECs are highly flexible, and display a uniform light emission with a luminance of 200 cd m?2 at a current conversion efficacy of 1.4 cd A?1. 相似文献
94.
95.
Martti Kuokkanen 《The Journal of mathematical sociology》2013,37(2-3):217-226
Gross’, Mason's and McEachern's role conflict theory with two incompatible role expectations is generalized by letting the number of incompatible role expectations increase. It is proved that the generalized theory is consistent and that its four axioms are independent. Three methodological results are proven. They show that the generalized theory is, in principle, testable from the point of view of three different well‐defined testing situations. Finally, it is shown that the original theory is a special case of the generalization. 相似文献
96.
Successful models of pure gravity mediation (PGM) with radiative electroweak symmetry breaking can be expressed with as few as two free parameters, which can be taken as the gravitino mass and \(\tan \beta \) . These models easily support a 125–126 GeV Higgs mass at the expense of a scalar spectrum in the multi-TeV range and a much lighter wino as the lightest supersymmetric particle. In these models, it is also quite generic that the Higgs mixing mass parameter, \(\mu \) , which is determined by the minimization of the Higgs potential is also in the multi-TeV range. For \(\mu >0\) , the thermal relic density of winos is too small to account for the dark matter. The same is true for \(\mu <0\) unless the gravitino mass is of order 500 TeV. Here, we consider the origin of a multi-TeV \(\mu \) parameter arising from the breakdown of a Peccei–Quinn (PQ) symmetry. A coupling of the PQ-symmetry breaking field, \(P\) , to the MSSM Higgs doublets, naturally leads to a value of \(\mu \sim \langle P \rangle ^2 /M_P \sim {\mathcal O}(100)\) TeV and of the order that is required in PGM models. In this case, axions make up the dark matter or some fraction of the dark matter with the remainder made up from thermal or non-thermal winos. We also provide solutions to the problem of isocurvature fluctuations with axion dark matter in this context. 相似文献
97.
98.
J. J. Dumont J. Lemonne G. Vanhomwegen F. Verbeure J. Wickens V. M. Hagman P. Keski-Kuha J. Tuominiemi K. Valtonen J. A. Estruch W. H. Evans P. Mason H. Muirhead J. F. Baland F. Grard P. Herquet C. Poiret G. Ekspong B. Selldén L. Szilly N. Yamdagni 《Zeitschrift fur Physik C Particles and Fields》1982,13(1):1-9
The elastic and inelastic \(\bar p\) p cross sections at 70 GeV/c have been determined in an experiment performed at CERN using BEBC equipped with a TST. The topological cross sections were measured and the moments of the inelastic multiplicity distribution are 〈n c 〉=6.16±0.09, 〈n c 〉/D=2.04±0.05 andf 2 cc =2.97±0.03. The average number of Dalitz pairs per inelastic event is (3.12±0.09)×10?2. Assuming that these all arise from π0 decay the average π0 multiplicity is \(\langle n_{\pi ^0 } \rangle = 2.71 \pm 0.14\) . The \(\bar p\) p?pp cross section differences lead to an annihilation cross section σ A = 4.42±0.41 mb and the moments of the annihilation multiplicty distribution are 〈n A 〉=8.0±0.3, 〈n A 〉/D=2.5±0.2 andf 2 A?? =?1.4±0.3. An independent check of σ A was made by investigating fast forward charged and neutral secondary interactions in the TST and in the surrounding neon-hydrogen mixture, and gives a value σ A = 5.0±1.6 mb. The ratio of fast \(\bar n\) to \(\bar p\) production in non-annihilation interactions at 70 GeV/c is found to be 0.45±0.11. 相似文献
99.
100.