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61.
There is a correspondence between functions in the maximal ideal of the local ring of a rational singularity and certain positive
divisors supported on the exceptional fiber of a resolution of the singularity. Here we give an algorithm to obtain a generating
set over ℤ of these divisors. 相似文献
62.
Meral Arnavut 《Journal of Pure and Applied Algebra》2007,208(2):739-760
In this article we consider finitely generated torsion-free modules over certain one-dimensional commutative Noetherian rings R. We assume there exists a positive integer NR such that, for every indecomposable R-module M and for every minimal prime ideal P of R, the dimension of MP, as a vector space over the field RP, is less than or equal to NR. If a nonzero indecomposable R-module M is such that all the localizations MP as vector spaces over the fields RP have the same dimension r, for every minimal prime P of R, then r=1,2,3,4 or 6. Let n be an integer ≥8. We show that if M is an R-module such that the vector space dimensions of the MP are between n and 2n−8, then M decomposes non-trivially. For each n≥8, we exhibit a semilocal ring and an indecomposable module for which the relevant dimensions range from n to 2n−7. These results require a mild equicharacteristic assumption; we also discuss bounds in the non-equicharacteristic case. 相似文献
63.
Meral FC Royston TJ Magin RL 《The Journal of the Acoustical Society of America》2011,129(2):1036-1045
A previous study of the authors published in this journal focused on mechanical wave motion in a viscoelastic material representative of biological tissue [Meral et al., J. Acoust. Soc. Am. 126, 3278-3285 (2009)]. Compression, shear and surface wave motion in and on a viscoelastic halfspace excited by surface and sub-surface sources were considered. It was shown that a fractional order Voigt model, where the rate-dependent damping component that is dependent on the first derivative of time is replaced with a component that is dependent on a fractional derivative of time, resulted in closer agreement with experiment as compared with conventional (integer order) models, such as those of Voigt and Zener. In the present study, this analysis is extended to another configuration and wave type: out-of-plane response of a viscoelastic plate to harmonic anti-symmetric Lamb wave excitation. Theoretical solutions are compared with experimental measurements for a polymeric tissue mimicking phantom material. As in the previous configurations the fractional order modeling assumption improves the match between theory and experiment over a wider frequency range. Experimental complexities in the present study and the reliability of the different approaches for quantifying the shear viscoelastic properties of the material are discussed. 相似文献
64.
Abe K Hayato Y Iida T Ikeda M Iyogi K Kameda J Koshio Y Kozuma Y Miura M Moriyama S Nakahata M Nakayama S Obayashi Y Sekiya H Shiozawa M Suzuki Y Takeda A Takenaga Y Takeuchi Y Ueno K Ueshima K Watanabe H Yamada S Yokozawa T Ishihara C Kaji H Lee KP Kajita T Kaneyuki K McLachlan T Okumura K Shimizu Y Tanimoto N Martens K Vagins MR Labarga L Magro LM Dufour F Kearns E Litos M Raaf JL Stone JL Sulak LR Goldhaber M Bays K Kropp WR Mine S Regis C Smy MB Sobel HW Ganezer KS Hill J Keig WE Jang JS 《Physical review letters》2011,107(24):241801
We present a search for differences in the oscillations of antineutrinos and neutrinos in the Super-Kamiokande-I, -II, and -III atmospheric neutrino sample. Under a two-flavor disappearance model with separate mixing parameters between neutrinos and antineutrinos, we find no evidence for a difference in oscillation parameters. Best-fit antineutrino mixing is found to be at (Δm2,sin2 2θ)=(2.0×10(-3) eV2, 1.0) and is consistent with the overall Super-K measurement. 相似文献
65.
66.
The heat shock proteins (HSPs) protect the other proteins in the process of folding under stressful conditions such as oxygen deprivation, hypothermy or presence of alcohol. They have also an important role in tumour invasion. In this paper, the existence, uniqueness and permanence properties for the solution of the mathematical model which focuses on the synthesis of HSP70 is proved. Moreover the numerical simulations are performed by using FDM, namely a combination of backward and forward Euler methods, and the results confirm the expected behaviour of the solution. 相似文献
67.
Ashie Y Hosaka J Ishihara K Itow Y Kameda J Koshio Y Minamino A Mitsuda C Miura M Moriyama S Nakahata M Namba T Nambu R Obayashi Y Shiozawa M Suzuki Y Takeuchi Y Taki K Yamada S Ishitsuka M Kajita T Kaneyuki K Nakayama S Okada A Okumura K Ooyabu T Saji C Takenaga Y Desai S Kearns E Likhoded S Stone JL Sulak LR Walter CW Wang W Goldhaber M Casper D Cravens JP Gajewski W Kropp WR Liu DW Mine S Smy MB Sobel HW Sterner CW Vagins MR Ganezer KS Hill J Keig WE Jang JS Kim JY Lim IT Ellsworth RW 《Physical review letters》2004,93(10):101801
Muon neutrino disappearance probability as a function of neutrino flight length L over neutrino energy E was studied. A dip in the L/E distribution was observed in the data, as predicted from the sinusoidal flavor transition probability of neutrino oscillation. The observed L/E distribution constrained nu(micro)<-->nu(tau) neutrino oscillation parameters; 1.9x10(-3)0.90 at 90% confidence level. 相似文献
68.
Cihan Topcu Fatih Coldur Bulent Caglar K. Volkan Ozdokur Osman Cubuk 《Electroanalysis》2022,34(3):474-484
A novel solid-state electrochemical sensor based on a newly synthesized cross-linked copper(II) doped-copolymer and carbon nanotube material was developed for the direct determination of monohydrogen phosphate ions (HPO42−). The synthesized copolymers were characterized by FTIR, XPS, TG/DTG-DTA and SEM techniques. The sensor had a Nernstian slope:-30.7±0.4 mV/decade, linear concentrations range: 1.0×10−6 - 1.0×10−1 M, detection limit: 6.5×10−7 M, response time: 4 s and life time: 17 weeks. The sensor displayed constant potentials in the pH range 7.0-9.5. The sensor was successfully used as an indicator electrode in potentiometric titration and the direct determination of HPO4 2− in water samples. 相似文献
69.
In this study, free‐standing polymer films were obtained first with an electrochemical coating of polyaniline and then with a coating of polypyrrole on an insulating polycarbonate‐coated Pt electrode. The films contained varying amounts of polyaniline and polypyrrole obtained by varying the electrolysis time, and their conductivities were determined. The Raman spectra of the films taken from the electrode side were similar to those of pure polyaniline, whereas the spectra of the solution side were identical to those of pure polypyrrole. The resistance change in the films between −15 and +120°C revealed that the films were sensitive to temperature. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 51–59, 2000 相似文献
70.
Tau neutrinos favored over sterile neutrinos in atmospheric muon neutrino oscillations 总被引:1,自引:0,他引:1
Fukuda S Fukuda Y Ishitsuka M Kajita T Kameda J Kaneyuki K Kobayashi K Koshio Y Miura M Moriyama S Nakahata M Nakayama S Obayashi Y Okada A Okumura K Sakurai N Shiozawa M Suzuki Y Takeuchi H Takeuchi Y Toshito T Totsuka Y Yamada S Earl M Habig A Kearns E Messier MD Scholberg K Stone JL Sulak LR Walter CW Goldhaber M Barszczak T Casper D Gajewski W Kropp WR Mine S Price LR Smy M Sobel HW Vagins MR Ganezer KS Keig WE Ellsworth RW Tasaka S Kibayashi A Learned JG Matsuno S Takemori D 《Physical review letters》2000,85(19):3999-4003
The previously published atmospheric neutrino data did not distinguish whether muon neutrinos were oscillating into tau neutrinos or sterile neutrinos, as both hypotheses fit the data. Using data recorded in 1100 live days of the Super-Kamiokande detector, we use three complementary data samples to study the difference in zenith angle distribution due to neutral currents and matter effects. We find no evidence favoring sterile neutrinos, and reject the hypothesis at the 99% confidence level. On the other hand, we find that oscillation between muon and tau neutrinos suffices to explain all the results in hand. 相似文献