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The thermal conductivity of boron nitride/ethylene glycol (BN/EG) nanofluids was investigated by transient hot-wire method and two abnormal phenomena was reported. One is the abnormal higher thermal conductivity enhancement for BN/EG nanofluids at very low-volume fraction of particles, and the other is the thermal conductivity enhancement of BN/EG nanofluids synthesized with large BN nanoparticles (140 nm) which is higher than that synthesized with small BN nanoparticles (70 nm). The chain-like loose aggregation of nanoparticles is responsible for the abnormal increment of thermal conductivity enhancement for the BN/EG nanofluids at very low particles volume fraction. And the difference in specific surface area and aspect ratio of BN nanoparticles may be the main reasons for the abnormal difference between thermal conductivity enhancements for BN/EG nanofluids prepared with 140- and 70-nm BN nanoparticles, respectively.

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This paper presents a comprehensive procedure to calculate steady dynamic response and noise radiation generated by a gear reducer. In this process, the bearing force is obtained by solving the transmission system dynamic model, which is taken as the excitation of the gearbox, the noise generated by the gearbox vibration is researched by using FEM/BEM, so the dynamic characteristics of gear transmission and gearbox structure are demonstrated. Then the time history of node dynamic response and noise spectrum of the gearbox are obtained, and the effect of the excitation of frequency doubling of mesh frequency on the gearbox vibration and noise radiation is illustrated. The changes in radiated noise of gear reducers with load are calculated respectively by using both simulation and Kato's formulae, and results agree well with each other. The frequency range of the gearbox resonance is obtained by analyzing the spectral maps of the vibration and noise under the case of engine speed steadily increased. The study provides useful theoretical guideline to the design of the gearbox.

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Cubylcarbinylamine (1a), (4-cyclopropylcubyl)carbinylamine (1b), and (4-phenylcubyl)carbinylamine (1c) were synthesized and shown to be time-dependent, irreversible inactivators of monoamine oxidase B (MAO B). Substrate protects the enzyme from inactivation, but beta-mercaptoethanol does not, suggesting that these compounds are mechanism-based inactivators. All three compounds were also substrates for MAO B with partition ratios ranging from 152 to 536. The 4-substituted analogues were more potent inactivators than the unsubstituted analogue, indicating a benefit to 4-substitution in this class of inactivators.