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101.
In this paper, we propose a general smoothing Broyden-like quasi-Newton method for solving a class of nonsmooth equations. Under appropriate conditions, the proposed method converges to a solution of the equation globally and superlinearly. In particular, the proposed method provides the possibility of developing a quasi-Newton method that enjoys superlinear convergence even if strict complementarity fails to hold. We pay particular attention to semismooth equations arising from nonlinear complementarity problems, mixed complementarity problems and variational inequality problems. We show that under certain conditions, the related methods based on the perturbed Fischer–Burmeister function, Chen–Harker–Kanzow–Smale smoothing function and the Gabriel–Moré class of smoothing functions converge globally and superlinearly. 相似文献
102.
This study investigated effects of a previous sound presentation at the absolute threshold of hearing. Changes in threshold were measured when a pure tone at 60 dB SPL preceded a test tone in the contra- or ipsilateral ear. When the previous and test sounds both had the same frequency of 500 Hz, threshold decreased approximately 2 dB in the contralateral ear, and increased slightly in the ipsilateral ear. On the other hand, when the frequency of the previous sound differed from that of the test sound, the threshold was decreased slightly in the ipsilateral ear. 相似文献
103.
104.
Machida K Takehara E Kobayashi H Kikuchi M 《Chemical & pharmaceutical bulletin》2003,51(12):1417-1419
Two new iridoid glycosides, 7 beta,8 beta-epoxy-8 alpha-dihydrogeniposide (1) and 8-epiapodantheroside (2), were isolated, together with six known (3-8) and three artifact (9-11) iridoids, from the leaves of Gardenia jasminoides cv. fortuneana Hara. Their structures were established based on chemical and spectral data. 相似文献
105.
106.
This paper is concerned with the stationary problem of the Stokes equation in an infinite layer and provides a condition on
the external force sufficient for the existence of the solution. Since the Poiseuille flow is a solution to the homogeneous
equation, the solution is not unique when p = ∞. It is also proved that, under some suitable conditions, solutions to the homogeneous equation are limited only to the
Poiseuille flow. 相似文献
107.
Makoto Obata Noriko Matsuura Kazunori Mitsuo Hiroki Nagai Keisuke Asai Masafumi Harada Shiho Hirohara Masao Tanihara Shigenobu Yano 《Journal of polymer science. Part A, Polymer chemistry》2010,48(3):663-670
A novel methacrylate monomer bearing 5,10,15,20‐tetraphenylporphyrinato palladium(II) (PdTPP) (monomer 1a ) was synthesized and copolymerized with isobutyl methacrylate (IBM) and 2,2,2‐trifluoroethyl methacrylate (TFEM) to give poly (IBM‐co‐TFEM) bearing PdTPP (copolymer 2a ) as a dye‐conjugated oxygen‐permeable polymer for pressure‐sensitive paint applications. The introduction of PdTPP into copolymer 2a was confirmed by UV–vis spectroscopy and extended X‐ray absorption fine structure analysis. The Stern–Volmer plots of the copolymer 2a and a mixture of PdTPP and poly(IBM‐co‐TFEM) both showed downward curvature, unlike that of the platinum complex analogue (copolymer 2b ) previously reported. The plots were successfully fitted with a two‐site model to give two distinct Stern–Volmer constants (KSV1 and KSV2) and the partition ratio f1. Interestingly, the f1 values for the copolymer 2a were almost constant at about 0.98, whereas those of the mixture of PdTPP and poly(IBM‐co‐TFEM) increased from 0.889 to 0.967 as the temperature was increased. This finding suggests that there are two distinct microheterogeneities, one temperature‐dependent and the other temperature‐independent, in the mixture of PdTPP and poly(IBM‐co‐TFEM). The dye‐conjugation approach effectively eliminates the temperature‐dependent, but not the temperature‐independent microheterogeneity. The luminescence decays of copolymers 2a and 2b and the corresponding mixtures in the absence of oxygen indicated that the temperature‐dependent microheterogeneity involves an oxygen diffusion process, whereas the temperature‐independent one appears to be inherent nature in PdTPP. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 663–670, 2010 相似文献
108.
A common ribbon-like structure was found in the crystals of triptycenequinones (TPQs), triptycene-TCNQs (TP-TCNQs) and their clathrates. The characteristic structure can be regarded as a supramolecular unit the formation of which is aided by weak intermolecular D–A interactions. This view is supported by the host–guest D–A interactions appeared in the crystals of the clathrates of 5,8-dimethyl-TPQ and 5,8-dimethoxy-TP-TCNQ. Intermolecular C–HO hydrogen bonds seem to be present in TPQ derivatives. 相似文献
109.
Shigenori Matsushima Kenji Obata Masao Arai 《Journal of Physics and Chemistry of Solids》2003,64(12):2417-2421
The electronic structures of undoped and N-doped InTaO4 with optimized structures are calculated within the framework of the density functional theory. Calculated lattice constants are in excellent agreement with experimental values, within a difference of 2%. The valence band maximum (VBM) is located near the middle point on the ZD line and the conduction band minimum (CBM) near the middle point on the DX line. This means that InTaO4 is an indirect-gap material and a minimum theoretical gap between VBM and CBM is ca. 3.7 eV. The valence band in the range from −6.0 to 0 eV mainly consists of O 2p orbitals, where In 4d5s5p and Ta 5d orbitals are slightly hybridized with O 2p orbitals. On the other hand, the conduction band below 5.5 eV is mainly composed of the Ta 5d orbitals and the contributions of In and O orbitals are small. The band gap of N-doped InTaO4 decreases by 0.3 eV than that of undoped InTaO4, because new gap states originating from N 2p orbitals appear near the top of the valence band. This result indicates that doping of N atoms into metal oxides is a useful method to develop photocatalysts sensitive to visible light. 相似文献
110.
We consider a massless scalar Bose field interacting with two particles, one of them infinitely heavy. Neither an infrared nor an ultraviolet cutoff is imposed. In case the charge of the particles is of the same sign and sufficiently small, we prove the existence of a ground state. 相似文献