El Inca: The Life and Times of Garcilaso de la Vega. By John Grier Varner. (Austin: University of Texas Press, 1968. The Texas Pan American Series. Pp. xiv, 413. $10.00.)

Over the past two years, a series of papers have been published concerning bearing temperature trending and a mechanism to explain this troubling phenomenon. In September of 2008, a collaborative field test between The Union Pacific Railroad (UP), Amsted Rail, Rail Sciences Inc. (RSI), and The University of Texas-Pan American (UTPA) was conducted to corroborate the findings of laboratory research and testing. Field and laboratory results confirm that temperature trended bearings exhibit vibration signals that can be distinguished from healthy bearings. Distinct primary frequencies and overtones associated with the axle, cone, cage, and rollers can be readily identified within a bearing vibration signal. In a previous paper, it was demonstrated that a trended bearing exhibits vibrations of higher magnitude. However, all characteristic frequencies appear in both healthy and trended bearings, but those that dominate, i.e., have higher magnitude, are distinct for trended bearings when compared to healthy bearings. The latter can be repeatedly demonstrated in both field and laboratory experiments. Moreover, the current work identifies and distinguishes between the primary bearing frequencies and those linked to roller misalignment, which is known to increase friction and wear, and consequently raise the bearing temperature.

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Organic Functional Group Conversion

Organic Synthesis ◽

10.1093/oso/9780199965724.003.0005 ◽

2013 ◽

Author(s):

Douglass F. Taber

Keyword(s):

Hong Kong ◽

Allylic Alcohol ◽

Primary Alcohols ◽

National Chemical Laboratory ◽

Chemical Laboratory ◽

University Of Texas ◽

University Of Wisconsin ◽

Pan American ◽

Acetate Formation ◽

The University

Pradeep Kumar of the National Chemical Laboratory, Pune, developed (Tetrahedron Lett. 2010, 51, 744) a new procedure for the conversion of an alcohol 1 to the inverted chloride 3. Michel Couturier of OmegaChem devised (J. Org. Chem. 2010, 75, 3401) a new reagent for the conversion of an alcohol 4 to the inverted fluoride 6. For both reagents, primary alcohols worked as well. Patrick H. Toy of the University of Hong Kong showed (Synlett 2010, 1115) that diethyl-lazodicarboxylate (DEAD) could be used catalytically in the Mitsunobu coupling of 7. Employment of 8 minimized competing acetate formation. In another application of hyper-valent iodine chemistry, Jaume Vilarrasa of the Universitat de Barcelona observed (Tetrahedron Lett. 2010, 51, 1863) that the Dess-Martin reagent effected the smooth elimination of a pyridyl selenide 10. Ken-ichi Fujita and Ryohei Yamaguchi of Kyoto University extended (Org. Lett. 2010, 12, 1336) the “borrowed hydrogen” approach to effect conversion of an alcohol 12 to the sulfonamide 13. Dan Yang, also of the University of Hong Kong, developed (Org. Lett. 2010, 12, 1068, not illustrated) a protocol for the conversion of an allylic alcohol to the allylically rearranged sulfonamide. Shu-Li You of the Shanghai Institute of Organic Chemistry used (Org. Lett. 2010, 12, 800) an Ir catalyst to effect rearrangement of an allylic sulfinate 14 to the sulfone. Base-mediated conjugation then delivered 15. K. Rama Rao of the Indian Institute of Chemical Technology, Hyderabad, devised (Tetrahedron Lett. 2010, 51, 293) a La catalyst for the conversion of an iodoalkene 16 to the alkenyl sulfide 17. Alkenyl selenides could also be prepared. James M. Cook of the University of Wisconsin, Milwaukee, described (Org. Lett. 2010, 12, 464, not illustrated) a procedure for coupling alkenyl iodides and bromides with N-H heterocycles and phenols. Hansjörg Streicher of the University of Sussex showed (Tetrahedron Lett. 2010, 51, 2717) that under free radical conditions, the carboxylic acid derivative 18 could be decarboxylated to the alkenyl iodide 19. Bimal K. Banik of the University of Texas–Pan American found (Synth. Commun. 2010, 40, 1730) that water was an effective solvent for the microwave-mediated addition of a secondary amine 21 to a Michael acceptor 20.

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