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This paper deals with the dependence of the solutions and the associated multipliers of a nonlinear programming problem when the data of the problem are subjected to small perturbations. Sufficient conditions are given which imply that the solutions and the multipliers of a perturbed nonlinear programming problem are Lipschitzian with respect to the perturbations.The authors wish to thank J. Drèze and J. P. Vial for many helpful discussions and J. B. Hiriart-Urruty for comments on a previous version of the paper.  相似文献   
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Two series of ammonium—chromium exchanged zeolites, CrzNH4yNaxY obtained by ionic exchange and Crz′NH4y′HY/T for which an intermediate form NH4yNaxY has been steamed, are investigated by use of TGA, DTA and X-ray. Introduction of chromium effectively stabilizes the structure. Measurements of hydration and hydroxylation levels show that dehydroxylation of the bulk occurs early due to the fixation of chromium ions and that thermostable hydroxyls are present. The stability of chromium exchanged zeolites occurs through the occupation of cavities by oxocations. Generally self-steaming takes place and zeolites change into a mixture of both wet- and dried-air treated forms.  相似文献   
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The rotational spectra of formaldehyde, H212C16O and its isotopic species H213C16O, H212C18O, and H213C18O have been investigated in the ground vibrational state in the frequency region between 8 and 460 GHz. For most cases in which measurements of the a-type R- and Q-branch transitions already existed the accuracy of the line position has been improved to about 10 kHz. For H212C16O and H213C16O a large number of ΔKa = ±2 transitions were measured with similar accuracy. These new data when combined with all other available data and appropriate weightings lead to a set of ground state parameters which for the first time are compatible with infrared and ultraviolet data. The rotational constants (and 3σ standard deviations) obtained using Watson's A-reduced Hamiltonian are:
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We study the production of a pair of light, neutral, CP-even Higgs bosons in photon–photon collisions within the general Two Higgs Doublet Model (THDM). This is a process for which the lowest order contribution in both, the Standard Model and the THDM, appears at one loop. We find that the cross section for this process can be much larger in the THDM than in the Standard Model and the number of events expected at the Photon Collider will allow a determination of some of the parameters in the scalar potential.  相似文献   
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The [NpO2(DPPMO2)2Cl][NpO2Cl4] complex (where DPPMO2 = bis(diphenylphosphino)methanedioxide) contains the linear neptunyl group, {NpO2}2+, with two bidentate P=O donor ligands. Coordinating anion Cl? fills the fifth equatorial coordination site yielding a complex of general formula [NpO2(DPPMO2)2X]2[Y] (1) (where X = Cl? and Y = [NpO2Cl4]2?. Reaction between our newly prepared neptunium starting material [NpO2Cl2(thf)]n and phosphinimine ligand produced crystals of [Ph3PNH2]2[NpO2Cl4] (2). Compounds 1 and 2 have been structurally characterised.  相似文献   
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The present work is focused on the numerical approximation of the shallow water equations. When studying this problem, one faces at least two important issues, namely the ability of the scheme to preserve the positiveness of the water depth, along with the ability to capture the stationary states.We propose here aGodunov-typemethod that fully satisfies the previous conditions, meaning that the method is in particular able to preserve the steady states with non-zero velocity.  相似文献   
H212C16OH213C16OH212C18OH213C18O
A/MHz281 970.572 (24)281 993.258(135)281 961.94 (39)281 985.00 (93)
B/MHz38 836.0456(13)37 811.0887(25)36 904.1693(66)35 859.256(10)
C/MHz34 002.2034(12)33 213.9790(25)32 511.5311(63)31 697.868(10)
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