The free-volume viscosity model can accurately predict the temperature-pressure-viscosity relationship of lubricants. However, it is seldom used in elastohydrodynamic lubrication (EHL) simulation. This paper presents the application of the free-volume viscosity model in a Newtonian EHL simulation of a squalane-lubricated circular contact. Good agreement is observed between available experimental data and simulation results. The pressure-viscosity coefficients fit from viscometer data are also discussed. A recently developed definition of the coefficient is used to compare the coefficient value extracted from EHL film thickness interference measurements. Results indicate that the coefficient values from the curve fitting and EHL film thickness extraction agree well which has not been previously observed. Two factors help achieve this agreement: the new coefficient definition and smaller prediction error when using the Hamrock-Dowson formula in the cases studied. The effects of different pressure-viscosity relationships, including the exponential model, the Roelands model and the free-volume model, are investigated through an example with bright stock mineral oil. It is found that the real pressure-viscosity behavior predicted by the free-volume model yields a higher viscosity at the low-pressure area which results in a larger central film thickness. Therefore, due to use of the freevolume model, the present results are more consistent with experimental observations than previously reported numerical results.

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Deterministic quantum computation with one qubit (DQC1) is iconic in highlighting that exponential quantum speedup may be achieved with negligible entanglement. Its discovery catalyzed heated study of general quantum resources, and various conjectures regarding their role in DQC1's performance advantage. Coherence and discord are prominent candidates, respectively characterizing non-classicality within localized and correlated systems. Here we realize DQC1 within a superconducting system, engineered such that the dynamics of coherence and discord can be tracked throughout its execution. We experimentally confirm that DQC1 acts as a resource converter, consuming coherence to generate discord during its operation. Our results highlight superconducting circuits as a promising platform for both realizing DQC1 and related algorithms, and experimentally characterizing resource dynamics within quantum protocols.

Abstract:We report an efficient high-output periodically diode side-pumped electro-optical (EO) Q-switched Nd:YAG/KGd(WO 4 ) 2 coupled-cavity Raman laser with conductive and air cooling. A maximum pulse energy of 126 mJ and a peak power of 21 MW are achieved at the first order Stokes wavelength of 1177 nm under the diodes energy of 694 mJ, corresponding to an overall Diode-Stokes conversion efficiency of 18.2%, a slope efficiency of 28.8%, and a fundamental-Stokes coupling efficiency of 51.6%. Diode-Stokes overall optical efficiency, diode-Stokes slope efficiency, and fundamental-Stokes coupling efficiency with respect to incident pump energy at 808 nm

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A new compound, kaempferol 3-O-(2''-O-galloylrutinoside) (1), was isolated from the white flower of Nymphaea candida, together with nine known flavonol glycosides, kaempferol (2), kaempferol 3-O-beta-D-glucopyranoside (3), kaempferol 3-O-alpha-l-rhamnopyranoside (4), kaempferol 3-O-alpha-l-rhamnopyranosylglucopyranoside (5), kaempferol 7-O-beta-D-glucopyranoside 3-(O-alpha-l-rhamnopyranosylglucopyranoside) (6), quercetin (7), quercetin 3-O-beta-D-xylopyranoside (8), myricetin (9), myricetin 3'-O-beta-D-xylopyranoside (10). The structure of 1 was established on the basis of the analysis of its 1D and 2D NMR spectral data. Compounds 1-7 and 9 exhibited moderate to significant antioxidant activities, which were evaluated by measurement of low-density lipoprotein (LDL) and malondialdehyde (MDA) levels in vitro. Compounds 1, 3, 4, 6 and 9 exhibited promising neuroprotective effects on ischemic injury model of cultured rat cortical neurons treated with sodium dithionite in glucose-free medium. Furthermore, compounds 1, 5, and 9 had distinct cytotoxicity to adrenal gland pheochromocytoma, PC12 cells, being treated by the same way.