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Ronda M. Sandifer Lynn M. Shaffer Wayne M. Hollinger David C. Reames Charles F. Beam 《Journal of heterocyclic chemistry》1976,13(3):607-608
Several C(α),O-dilithiooximes of aromatic ketones were condensed with aroyl chlorides. The presumed diacyl intermediates were not isolated, and the reaction mixtures containing them were acid-cyclized to give 4-acylisoxazoles in 22–62% yield. 相似文献
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A comparison is made of the chemisorption behavior of H2 and CO over a carbided and nitrided Ni(100) surface. These results together with previous results for S and Cl support the argument that adatom electronegativity rather than radius is primarily responsible for modification of chemisorption behavior. 相似文献
125.
Vocalization and breathing were studied in 40 healthy infants, including five boys and five girls each at ages 5 weeks, 2.5 months, 6.5 months, and 12 months. Breathing was monitored through the use of a variable inductance plethysmograph that enabled estimates of the volume changes of the rib cage, abdomen, and lung, as well as estimates of selected temporal features of the breathing cycle. Four vocalization types were studied intensively. These included cries, whimpers, grunts, and syllable utterances. Breathing behavior was highly variable across the four vocalization types, demonstrating the degrees of freedom of performance available to the infant to accomplish the aeromechanical drive required. Such behavior was influenced by body length, body position, and age, but not by vocalization type and sex. The protocol established is a useful tool for observing the natural course of the emergence of vocalization and breathing during the first year of life. 相似文献
126.
Using a DC-biased room-temperature photoconductive switching element, a picosecond resolution optical streak camera is operated at sweep rates up to 7 ps/mm. Single-shot jitter is 2 ps with complete absence of short and long-term drift characteristic of all other sweep drivers. This high accuracy allows the streak camera to be used in a single-shot averaging mode which leads to a sub-picosecond absolute timing accuracy. When operated in this manner, the streak camera becomes a highly reliable and accurate device for measuring transient events on a time scale of single picoseconds. The simplicity of this method makes it highly attractive for many applications in laser fusion and picosecond chemistry and photophysics studies where reliable no-drift operation is highly desirable. 相似文献
127.
Robert E. Stevens Phillip C.C. Liu Wayne L. Gladfelter 《Journal of organometallic chemistry》1985,287(1):133-143
The reaction of PP(NO2) with M4(CO)12 (M = Co, Rh) gives the nitrido clusters [M6N(CO)15]? in 13 and 21% yields, respectively. A high yield synthesis (77%) of [Rh6N(CO)15)]? directly from Rh6(CO)16 and PPN(NO2) is also presented. PPN(NO2) reacts with Ir4(CO)12 to give the new isocyanato cluster, [Ir4(NCO)(CO)11]? in 34% yield, while the direct synthesis of this isocyanate product occurs in 77% yield from PPN(N3) and Ir4(CO)12. Modifications of published procedures for the preparation of [N(C2H5)4]2 [Ir6(CO)15] and Ir6(CO)16 are reported that allow shorter reaction times and give higher yields. The reaction of Ir6(CO)16 with one equivalent of PPN(NO2) generates a new cluster, PPN[Ir6(CO)15(NO)], in 57% yield which is proposed to contain a bent nitrosyl ligand. An additional equivalent of PPN(NO2) gives (PPN)2[Ir6(CO)15] in 84% yield with the evolution of N2O as well as CO2. 相似文献
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D. P. Neikirk Wayne W. Lam D. B. Rutledge 《International Journal of Infrared and Millimeter Waves》1984,5(3):245-278
The bismuth microbolometer is a simple, easily made detector suitable for use throughout the far-infrared, which has been integrated with a variety of planar antennas. The general thermal properties of these devices and some of the constraints on bolometer materials are discussed. The fabrication and performance of several different types of microbolometers and microthermocouples are described.Supported by the Department of Energy contract DE-AM03-765F-00010 Task IIA; Army Research Office contract DAAG29-82-K-0165; and the Jet Propulsion Laboratory through Dr. M. Litvak. 相似文献