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91.
Ohne Zusammenfassung 相似文献
92.
Abbott B Abbott R Adhikari R Ageev A Allen B Amin R Anderson SB Anderson WG Araya M Armandula H Ashley M Asiri F Aufmuth P Aulbert C Babak S Balasubramanian R Ballmer S Barish BC Barker C Barker D Barnes M Barr B Barton MA Bayer K Beausoleil R Belczynski K Bennett R Berukoff SJ Betzwieser J Bhawal B Bilenko IA Billingsley G Black E Blackburn K Blackburn L Bland B Bochner B Bogue L Bork R Bose S Brady PR Braginsky VB Brau JE Brown DA Bullington A Bunkowski A Buonanno A Burgess R Busby D 《Physical review letters》2005,94(18):181103
We place direct upper limits on the amplitude of gravitational waves from 28 isolated radio pulsars by a coherent multidetector analysis of the data collected during the second science run of the LIGO interferometric detectors. These are the first direct upper limits for 26 of the 28 pulsars. We use coordinated radio observations for the first time to build radio-guided phase templates for the expected gravitational-wave signals. The unprecedented sensitivity of the detectors allows us to set strain upper limits as low as a few times 10(-24). These strain limits translate into limits on the equatorial ellipticities of the pulsars, which are smaller than 10(-5) for the four closest pulsars. 相似文献
93.
Brady SK Conradi MS Vaccaro CM 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2005,172(2):342-345
Composite materials of epoxy resins reinforced by carbon fibers are increasingly being used in the construction of aircraft. In these applications, the material may be thermally damaged and weakened by jet blast and accidental fires. The feasibility of using proton NMR relaxation times T1, T1rho, and T2 to detect and quantify the thermal damage is investigated. In conventional spectrometers with homogeneous static magnetic fields, T1rho is readily measured and is found to be well correlated with thermal damage. This suggests that NMR measurements of proton T1rho may be used for non-destructive evaluation of carbon fiber-epoxy composites. Results from T1rho measurements in the inhomogeneous static and RF magnetic fields of an NMR-MOUSE are also discussed. 相似文献
94.
Elliott JB Moretto LG Phair L Wozniak GJ Albergo S Bieser F Brady FP Caccia Z Cebra DA Chacon AD Chance JL Choi Y Costa S Gilkes ML Hauger JA Hirsch AS Hjort EL Insolia A Justice M Keane D Kintner JC Lindenstruth V Lisa MA Matis HS McMahan M McParland C 《Physical review letters》2000,85(6):1194-1197
It is shown that the Fisher droplet model, percolation, and nuclear multifragmentation share the common features of reducibility (stochasticity in multiplicity distributions) and thermal scaling (one-fragment production probabilities are Boltzmann factors). Barriers obtained, for cluster production on percolation lattices, from the Boltzmann factors show a power-law dependence on cluster size with an exponent of 0.42+/-0.02. The EOS Collaboration Au multifragmentation data yield barriers with a power-law exponent of 0.68+/-0.03. Values of the surface energy coefficient of a low density nuclear system are also extracted. 相似文献
95.
We present a novel sensor that measures the entire spatial coherence function within an aperture by use of a variable astigmatic lens. This sensor permits digital capture and processing of partially coherent fields. We demonstrate the sensor by sampling and computing the coherent modes of a three-dimensional incoherent source. 相似文献
96.
Optical activity and conformation of the cation carrier X537A 总被引:3,自引:0,他引:3
97.
98.
99.
Gordon K. Pagenkopf William Brady Judy Clampet Michael A. Purcell 《Analytica chimica acta》1978,98(1):177-179
The interaction of [PdCl4]2-aqwith ethylene-bis(thioglycolic) acid (EBTGA) and β-ethylthioethylene(thioglycolic) acid (β-ETETGA), has been interpreted and evaluated quantitatively. The successive constants of palladium(II) with EBTGA and/or β-ETETGA in acid medium have been determined spectrophotometrically. 相似文献
100.