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11.
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Gordon D. Pusch 《General Relativity and Gravitation》1987,19(3):225-231
The Eötvös, Dicke, and Braginski experiments do not rule out the recent suggestion that the weak equivalence principle (WEP) might be violated at intermediate ranges (10–1 m r 104 m). I briefly discuss the problems inherent in Eötvös-type apparatus in searches for WEP-violating forces (hyperforces) between laboratory masses and suggest an alternative detector free of such problems. The proposed detector is driven by a hyperforce torque at the rotational frequency. If the detector is tuned to this frequency, the signal, enhanced by resonance, may be detected synchronously. I derive the response equations for the detector and discuss how spurious responses due to gravity torques may be suppressed.This essay received the third award from the Gravity Research Foundation for the year 1986-Ed. 相似文献
13.
We consider the relaxation dynamics of two quantum levels coupled to a stochastic bath. We emphasize that even if the matrix elements of the fluctuating Hamiltonian are Gaussian, a second-order cumulant truncation is not exact. For various stochastic models, including the case of a spin-1/2 particle in a fluctuating magnetic field, we calculate 1/T
1, the population relaxation rate, and 1/T
2, the phase relaxation rate, up to fourth order in perturbation theory. We show that unlike the commonly accepted second-order result that 1/T
21/2T
1, when fourth-order terms are included, in some instances 1/T
2<1/2T
1. 相似文献
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The Diels-Alder reaction between 9-alkyl-1,4-dihydronaphthalen-1,4-imines () and 2-alkylisoindoles () occurs in refluxing xylene to give exclusively the exo-endo cyclo-adducts (). 相似文献
16.
D. H. Beebe C. E. Gordon R. N. Thudium M. C. Throckmorton T. L. Hanlon 《Journal of polymer science. Part A, Polymer chemistry》1978,16(9):2285-2301
A quantitative procedure has been developed for characterizing the complete microstructure of polymers of 1,3-pentadiene, including the tacticity of any crystalline component. This can be accomplished by a combination of infrared spectroscopy, X-ray crystallinity, and 300-MHz NMR spectroscopy. A series of high structural purity polymers were synthesized with a series of previously unreported mixed microstructures. These samples were characterized by using the three techniques mentioned, including the previously unreported 300-MHz NMR data. With those results a 60-MHz NMR/IR method of spectroscopy was developed to determine the composition of poly(1,3-pentadiene)s in terms of percent cis-1,2-, cis-1,4-, trans-1,4-, and 3,4-pentadiene units. 相似文献
17.
I.A. Boriev E.B. Gordon A.A. Nadeikin A.I. Nikitin V.L. Talrose A.M. Velichko 《Chemical physics letters》1983,96(4):407-409
The primary yield of CF3I multiphoton dissociation under CO2-laser irradiation has been determined by direct monitoring of iodine atoms using a pulsed iodine laser. The primary yield was found to exceed markedly an observed MPD yield obtained from measurement of the CF3I consumption not only in CF3I-N2 but also in CF3I-O2 mixtures. 相似文献
18.
The magnetic susceptibilities of cobaltocene and chromocene have been measured between 83 and 293 K; for cobaltocene the results suggest an appreciable orthorhombic splitting of the 2∏(σ2πδ4 ground state, whilst for chromocene the data provide further support for the 3Δ(σδ3) ground state previously deduced. 相似文献
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