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261.
In this paper, a methodology is presented for the cancellation of road noise, from the analysis of vibration transmission paths for an automotive suspension to the design of an active control system using inertial actuators on a suspension to reduce the vibrations transmitted to the chassis. First, experiments were conducted on a Chevrolet Epica LS automobile on a concrete test track to measure accelerations induced on the suspension by the road. These measurements were combined with experimental Frequency Response Functions (FRFs) measured on a quarter-car test bench to reconstruct an equivalent three dimensional force applied on the wheel hub. Second, FRFs measured on the test bench between the three-dimensional driving force and forces at each suspension/chassis linkage were used to characterize the different transmission paths of vibration energy to the chassis. Third, an experimental model of the suspension was constructed to simulate the configuration of the active control system, using the primary (disturbance) FRFs and secondary (control) FRFs also measured on the test bench. This model was used to optimize the configuration of the control actuators and to evaluate the required forces. Finally, a prototype of an active suspension was implemented and measurements were performed in order to assess the performance of the control approach. A 4.6 dB attenuation on transmitted forces was obtained in the 50–250 Hz range. 相似文献
262.
A new and convenient synthesis of a variety of N‐ and S‐substituted tetrazoles has been developed via azide and Mannich reaction methods. Compounds were characterized by elemental analysis, MALDI MS, and 1H NMR data. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:637–643, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20353 相似文献
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264.
Dr. Asfandyar Sikandar Dr. Alexander Popoff Dr. Ravindra P. Jumde Dr. Attila Mándi Dr. Amninder Kaur Dr. Walid A. M. Elgaher Dr. Lara Rosenberger Dr. Stephan Hüttel Dr. Rolf Jansen Dr. Maja Hunter Prof. Dr. Jesko Köhnke Prof. Dr. Anna K. H. Hirsch Prof. Dr. Tibor Kurtán Prof. Dr. Rolf Müller 《Angewandte Chemie (International ed. in English)》2023,62(40):e202306437
Even with the aid of the available methods, the configurational assignment of natural products can be a challenging task that is prone to errors, and it sometimes needs to be corrected after total synthesis or single-crystal X-ray diffraction (XRD) analysis. Herein, the absolute configuration of amidochelocardin is revised using a combination of XRD, NMR spectroscopy, experimental ECD spectra, and time-dependent density-functional theory (TDDFT)-ECD calculations. As amidochelocardin was obtained via biosynthetic engineering of chelocardin, we propose the same absolute configuration for chelocardin based on the similar biosynthetic origins of the two compounds and result of TDDFT-ECD calculations. The evaluation of spectral data of two closely related analogues, 6-desmethyl-chelocardin and its semisynthetic derivative 1 , also supports this conclusion. 相似文献
265.
Mabrouk Walid Jebri Sonia Charradi Khaled Silimi Bishir Alzahrani Abdullah Y. A. Boubakri Ali Ghodbane Ouassim Raouafi Noureddine Keshk Sherif. M. A. S. 《Journal of Solid State Electrochemistry》2023,27(4):991-999
Journal of Solid State Electrochemistry - In this study, graphene (G) was blended with sulfonated polyether sulfone octyl sulfonamide (SPESOS) in different ratios (1, 1.5, and 2 wt.%) to enhance... 相似文献