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101.
We give a mathematically rigorous proof of Nekrasov’s conjecture: the integration in the equivariant cohomology over the moduli
spaces of instantons on ℝ4 gives a deformation of the Seiberg-Witten prepotential for N=2 SUSY Yang-Mills theory. Through a study of moduli spaces on the blowup of ℝ4, we derive a differential equation for the Nekrasov’s partition function. It is a deformation of the equation for the Seiberg-Witten
prepotential, found by Losev et al., and further studied by Gorsky et al.
Mathematics Subject Classification (2000) 14D21, 57R57, 81T13, 81T60 相似文献
102.
H. H. Willard J. J. Thompson E. Kasper P. Slawik A. W. Middleton K. Seelkopf H. Taeger P. Schmidt F. Weyrauch A. Necke H. Müller A. J. Lindsey B. Park E. J. Lewis O. B. Winter Helen M. Robinson F. W. Lamb E. J. Miller C. E. Willoughby E. S. Wilkins E. O. Kraemer A. Jílek und J. Kota 《Fresenius' Journal of Analytical Chemistry》1936,106(4-6):200-207
Ohne Zusammenfassung 相似文献
103.
Geometric aspects of the extended interacting boson model (gIBM) withs, d andg bosons are studied using coherent states. Algebraic expressions for the coherent state expectation values of various terms in the general gIBM Hamiltonian are derived in terms of the quadrupole and hexadecupole deformation variablesβ 2 andβ 4 and the asymmetry angleγ. These in turn are used to determine the equilibrium shape parameters (β 2 0 ,β 4 0 ,γ 0) in the seven dynamical symmetry limits of gIBM. 相似文献
104.
Gold‐Catalyzed Enantioselective Synthesis,Crystal Structure,and Photophysical/Chiroptical Properties of Aza[10]helicenes
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Maya Tanaka Dr. Yu Shibata Kyosuke Nakamura Kota Teraoka Prof. Dr. Hidehiro Uekusa Dr. Kazuko Nakazono Prof. Dr. Toshikazu Takata Prof. Dr. Ken Tanaka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(28):9537-9541
The enantioselective synthesis of an aza[10]helicene, possessing two pyridone units, has been achieved by the gold‐catalyzed intramolecular quadruple hydroarylation of a tetrayne. This aza[10]helicene was successfully converted into a fully aromatic aza[10]helicene, possessing two pyridine units. Structure–photophysical and chiroptical properties relationship in a series of azahelicene isomers has also been disclosed. 相似文献
105.
106.
Noboru Watanabe Yohei Kamata Kota Yamauchi Yasuo Udagawa 《Journal of computational chemistry》2001,22(13):1315-1320
Total X‐ray scattering intensity σee(q) is very sensitive to electron correlation effects. In this study σee(q) of N2, CO, and N2O have been computed by the coupled cluster singles and doubles (CCSD) method and compared with configuration interaction singles and doubles (CISD) calculations as well as experimental observations. σee(q) curves by CCSD calculations are rather close to those by CISD, but although small, there still exist some discrepancies between calculated and observed values. © 2001 John Wiley & Sons, Inc. J Comput Chem 22: 1315–1320, 2001 相似文献
107.
We consider solving large sparse symmetric singular linear systems. We first introduce an algorithm for right preconditioned minimum residual (MINRES) and prove that its iterates converge to the preconditioner weighted least squares solution without breakdown for an arbitrary right‐hand‐side vector and an arbitrary initial vector even if the linear system is singular and inconsistent. For the special case when the system is consistent, we prove that the iterates converge to a min‐norm solution with respect to the preconditioner if the initial vector is in the range space of the right preconditioned coefficient matrix. Furthermore, we propose a right preconditioned MINRES using symmetric successive over‐relaxation (SSOR) with Eisenstat's trick. Some numerical experiments on semidefinite systems in electromagnetic analysis and so forth indicate that the method is efficient and robust. Finally, we show that the residual norm can be further reduced by restarting the iterations. 相似文献
108.
The aim of this work was to determine the effect of formulation of alginate beads on their mechani-cal behavior and stiffness when compressed at high speed. The alginate beads were formulated using different types and concentrations of alginate and gelling cations and were produced using an extrusion-dripping method. Single wet beads were compressed at a speed of 40 mm/min,and their elastic limits were investigated,and the corresponding force versus displacement data were obtained. The Young's moduli of the... 相似文献
109.
Reactions of 0.5 eq. of the dinuclear complexes [(η6-arene)Ru(μ-Cl)Cl]2 (arene = η6-C6H6, η6-p-iPrC6H4Me) and [(Cp∗)M(μ-Cl)Cl]2 (M = Rh, Ir; Cp∗ = η5-C5Me5) with 4,6-disubstituted pyrazolyl-pyrimidine ligands (L) viz. 4,6-bis(pyrazolyl)pyrimidine (L1), 4,6-bis(3-methyl-pyrazolyl)pyrimidine (L2), 4,6-bis(3,5-dimethyl-pyrazolyl)pyrimidine (L3) lead to the formation of the cationic mononuclear complexes [(η6-C6H6)Ru(L)Cl]+ (L = L1, 1; L2, 2; L3, 3), [(η6-p-iPrC6H4Me)Ru(L)Cl]+ (L = L1, 4; L2, 5; L3, 6), [(Cp∗)Rh(L)Cl]+ (L = L1, 7; L2, 8; L3, 9) and [(Cp∗)Ir(L)Cl]+ (L = L1, 10; L2, 11; L3, 12), while reactions with 1.0 eq. of the dinuclear complexes [(η6-arene)Ru(μ-Cl)Cl]2 and [(Cp∗)M(μ-Cl)Cl]2 give rise to the dicationic dinuclear complexes [{(η6-C6H6)RuCl}2(L)]2+ (L = L1, 13; L2, 14; L3, 15), [{(η6-p-iPrC6H4Me)RuCl}2(L)]2+ (L = L1, 16; L2, 17; L3, 18), [{(Cp∗)RhCl}2(L)]2+ (L = L1, 19; L2, 20; L3, 21) and [{(Cp∗)IrCl}2(L)]2+ (L = L1 22; L2, 23; L3 24). The molecular structures of [3]PF6, [6]PF6, [7]PF6 and [18](PF6)2 have been established by single crystal X-ray structure analysis. 相似文献
110.
A quite general approach for the preparation of η5-and η6-cyclichydrocarbon platinum group metal complexes is reported. The dinuclear arene ruthenium complexes [(η6-arene)Ru(μ-Cl)Cl]2 (arene = C6H6, C10H14 and C6Me6) and η5-pentamethylcyclopentadienyl rhodium and iridium complexes [(η6-C5Me5)M(μ-Cl)Cl]2 (M = Rh, Ir) react with 2 equiv. of 4-amino-3,5-di-pyridyltriazole (dpt-NH2) in presence of NH4PF6 to afford the corresponding mononuclear complexes of the type [(η6-arene)Ru(dpt-NH2)Cl]PF6 {arene = C10H14 (1), C6H6 (2) and C6Me6 (3)} and [(η6-C5Me5)M(dpt-NH2)Cl]PF6 {M = Rh (4), Ir (5)}. However, the mononuclear η5-cyclopentadienyl analogues such as [(η5-C5H5)Ru(PPh3)2Cl], [(η5-C5H5)Os(PPh3)2Br], [(η5-C5Me5)Ru(PPh3)2Cl] and [(η5-C9H7)Ru(PPh3)2Cl] complexes react in presence of 1 equiv. of dpt-NH2 and 1 equiv. of NH4PF6 in methanol yielded mononuclear complexes [(η5-C5H5)Ru(PPh3)(dpt-NH2)]PF6 (6), [(η5-C5H5)Os(PPh3)(dpt-NH2)]PF6 (7), [(η5-C5Me5)Ru(PPh3)(dpt-NH2)]PF6 (8) and [(η5-C9H7)Ru(PPh3)(dpt-NH2)]PF6 (9), respectively. These compounds have been totally characterized by IR, NMR and mass spectrometry. The molecular structures of 4 and 6 have been established by single crystal X-ray diffraction and some of the representative complexes have also been studied by UV–Vis spectroscopy. 相似文献