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1.
Several novel substituted bis(2‐pyridylimino)isoindolato (BPI) cobalt(II) and iron(II) complexes [M(BPI)(OAc)(H2O)] (M = Co: 1 ‐ 6, Fe: 7) have been synthesized by reaction of bis(2‐pyridylimino)isoindole derivatives with the corresponding metal(II) acetates. Reaction of 1‐6 with 1.5 ‐ 2 molar equivalents of t‐BuOOH gave the corresponding alkylperoxocobalt(III) complexes [Co(BPI)(OAc)(OOtBu)] (10 ‐ 15). Using an aqueous solution of t‐BuOOH (70 %), cyclohexene was selectively catalytically oxidized to the dialkylperoxide cyclohex‐2‐ene‐1‐t‐butylperoxide. 相似文献
2.
Nicolaj Søndberg-Jeppesen 《International Journal of Approximate Reasoning》2010,51(5):587-599
We consider the situation where two agents try to solve each their own task in a common environment. In particular, we study simple sequential Bayesian games with unlimited time horizon where two players share a visible scene, but where the tasks (termed assignments) of the players are private information. We present an influence diagram framework for representing simple type of games, where each player holds private information. The framework is used to model the analysis depth and time horizon of the opponent and to determine an optimal policy under various assumptions on analysis depth of the opponent. Not surprisingly, the framework turns out to have severe complexity problems even in simple scenarios due to the size of the relevant past. We propose two approaches for approximation. One approach is to use Limited Memory Influence Diagrams (LIMIDs) in which we convert the influence diagram into a set of Bayesian networks and perform single policy update. The other approach is information enhancement, where it is assumed that the opponent in a few moves will know your assignment. Empirical results are presented using a simple board game. 相似文献
3.
Both the computerized procedures investigated for x-ray fluorescence spectrometry exploit the fundamental parameter approach. Procedures 1 and 2 are without and with absolute calibration of the spectrometer, respectively. The basic fundamental parameter equations are shown and the equivalence with the notation of influence coefficients is demonstrated. The advantages and limitations of the two procedures are discussed. If the sample contains no appreciable fraction of light elements, procedure 1 is well suited for standardless quantitative calculations. Procedure 2 is not limited by this restriction, and its use may indicate if the qualitative elemental analysis is complete. Even in the case of incomplete qualitative analysis, procedure 2 gives usable quantitative results. Calibration inaccuracies with procedure 2 are easily tested by procedure 1, thus the two procedures complement each other. 相似文献
4.
The title compounds are prepared by arc‐melting of the elements followed by heating in Ta ampules (950—1150 °C, 1—12 h). 相似文献
5.
Leonid A. Kurdachenko Jose M. Muñoz-Escolano Javier Otal Nicolaj N. Semko 《Geometriae Dedicata》2009,138(1):69-81
Let F be a field and V a vector space over F. If G is a subgroup of GL(V, F), then we define the central dimension of
G (denoted by centdim
F
G) as the F-dimension of the factor-space V/C
V
(G). In this paper, we continue the study of locally nilpotent linear groups satisfying the weak minimal or the weak maximal
condition on their subgroups of infinite central dimension started in Kurdachenko et al. (Publ Mat 52:151–169, 2008).
Supported by Proyecto MTM2007-60994 of Dirección General de Investigación MEC (Spain). 相似文献
6.
Yurij Simonov Luigi Pietro Battaglia Anna Bonamartini Corradi Sandra Ianelli Giorgio Pelosi Edward Ganin Nicolaj Lukjanenko 《Journal of inclusion phenomena and macrocyclic chemistry》1990,9(3):181-194
The crystal structures of inclusion compounds of 4-aminobenzenesulfamidine (sulfaguanidine) (L) with two dicyclohexano-18-crown-6 (DCH-6) isomers A(cis-syn-cis) and B(cis-anti-cis) have been determined by X-ray methods. The complexes exhibit 1:2 host-guest ratios. In fact the complex of isomer A is formulated as [DCH-6A·[L]H2O]L (complexI), while that of isomerB is DCH-6
B
L2 (complex I1).In the crystals, host and guests are connected by O-H...0 and N-H...O bonds. 相似文献
7.
Dr. Bjarke S. Donslund Nicolaj Inunnguaq Jessen Giulio Bertuzzi Dr. Maxime Giardinetti Dr. Teresa A. Palazzo Mette Louise Christensen Prof. Dr. Karl Anker Jørgensen 《Angewandte Chemie (International ed. in English)》2018,57(40):13182-13186
The first peri‐ and stereoselective [10+4] cycloaddition between catalytically generated amino isobenzofulvenes and electron‐deficient dienes is described. The highly stereoselective catalytic [10+4] cycloaddition exhibits a broad scope with high yields, reflecting a robust higher‐order cycloaddition. Experimental and computational investigations support a kinetic distribution of intermediate rotamers dictating the enantioselectivity, which relies heavily on additive effects. 相似文献
8.
Galina S. Zaitseva Sergei S. Karlov Gleb V. Pen'kovoy Andrei V. Churakov Judith A. K. Howard Bettina A. Siggelkow Evgueni V. Avtomonov Jrg Lorberth 《无机化学与普通化学杂志》1999,625(4):655-660
The title compounds, viz. C13H8(R)Ge · (OCHMeCH2)3N ( 1 : R = H, 2 : R = Me3Si; 3 : R = Me3Ge) were prepared as mixtures of diastereomers by the reaction of N(CH2CHMeOSnAlk3)3 ( 7 : Alk = Et; 8 : Alk = Bu) with C13H8(R)GeBr3 ( 4 : R = H, 5 : R = Me3Si; 6 : R = Me3Ge), respectively. The synthesis of C13H8(Me3Sn)Ge · (OCHMeCH2)3N ( 13 ) by the reaction of germatrane ( 1 ) with Me3SnNMe2 is reported. Identity and structures were established by elemental analyses, 1H and 13C NMR spectroscopy and mass spectrometry. The crystal structure of 1 was determined by X‐ray diffraction methods. 相似文献
9.
Scholars studying human organizations have recently adopted the notion of fitness landscapes, a concept pioneered in the biological and physical sciences. Such scholars have generally assumed that organizations will migrate toward the local peaks of these landscapes, as biological and physical entities do. We use an agent‐based simulation to show, to the contrary, that a hierarchical human organization may very well come to rest at a “sticking point” that is not a local peak on the fitness landscape of the overall organization. Three pervasive features of human organizations create the distinction between sticking points and local peaks: the delegation of choices to separate decision makers, interdependencies between the domains of those decision makers, and differences between local incentives and global incentives. Our results illustrate both that it is valuable to use tools developed to study one type of complex adaptive system in order to examine another type and that researchers must adapt the tools with care as they attempt to do so. © 2002 Wiley Periodicals, Inc. 相似文献
10.
Dr. David McLeod Dr. Nicolaj Inunnguaq Jessen Dr. Thanh V. Q. Nguyen Marcus Espe Dr. Jeremy David Erickson Prof. Dr. Karl Anker Jørgensen Prof. Dr. Limin Yang Prof. Dr. K. N. Houk 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(71):e202202951
An unusual diastereodivergent stereoselective allylation reaction is presented. It consists of a palladium-catalyzed allylation reaction of an organocatalytically generated amino isobenzofulvene, where the diastereoselectivity is controlled by the electronic properties of a monodentate, achiral ligand on palladium. One major diastereoisomer is formed using triarylphosphines substituted with neutral or electron-donating substituents of the aryl group, while those with electron-withdrawing substituents favor the other diastereoisomer. The diastereoselectivity correlates with the Taft inductive parameter of substituents on the triarylphosphine ligand on palladium. The synergistic reaction involves both a catalytic secondary amine catalyst for the indene-aldehyde activation and the monodentate phosphine ligands on palladium, affording a highly enantioselective reaction with up to 98 % enantiomeric excess. Based on computational investigations, the role of the monodentate phosphine ligand on the diastereoselectivity is discussed. 相似文献