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91.
The courtship behaviors and cuticular hydrocarbons ofDrosophila rajasekari are described. Sexually mature males orient, tap, follow, vibrate their abdomens, extend and vibrate their wings, and attempt copulation during courtship. They perform these behaviors in response to immature and matureD. rajasekari of both sexes, and their courtship activities are facilitated by light. The predominant cuticular hydrocarbon found in both sexes is (Z,Z)-7,11-heptacosadiene (HCD), a compound known to be used as a courtship-stimulating sex pheromone by another fruit fly,D. melanogaster. Therefore, it is not surprising thatD. melanogaster males actively court both males and females from theD. rajasekari stock. However, HCD is apparently not used byD. rajasekari as a courtship-stimulating pheromone since matureD. rajasekari males do not courtD. melanogaster females, which produce large quantities of HCD. 相似文献
92.
(Z)-11-Octadecenyl acetate (Z11–18Ac) and (Z)-11-eicosenyl acetate (Z11–20Ac) were identified as the aggregation pheromones ofDrosophila ananassae, andZ11–20Ac was identified as the aggregation pheromone ofDrosophila bipectinata. Z11–18Ac andZ11–20Ac were not attractive alone; however, in combination with fermenting food odors, the acetates attracted flies of both sexes in a wind-tunnel olfactometer. The pheromones were present in the ejaculatory bulb of sexually mature male flies and transferred to the female during mating. MaleD. bipectinata released little if anyZ11–20Ac to the food; however, recently mated females releasedZ11–20Ac to the surrounding surfaces in just a few hours after mating.D. ananassae males, on the other hand, appeared to release moreZ11–18Ac andZ11–20Ac to the surroundings than mated females. AlthoughD. bipectinata males had noZ11–18Ac, flies were as attracted toZ11–18Ac as to an equal quantity ofZ11–20Ac.D. ananassae were attracted toZ11–18Ac but not toZ11–16Ac orZ11–20Ac. However,Z11–20Ac in combination withZ11–18Ac was significantly more attractive thanZ11–18Ac alone. 相似文献
93.
GAS ABSORPTION IN A HOLLOW FIBER DEVICE 总被引:6,自引:0,他引:6
The absorption of S02 and NH3 from air and air/CO 2 streams was studied for the first time in a certain novel hollow fiber mass transfer device, for various inlet gas compositions, liquid compositions, gas flow rates, and liquid flow rates. The gas and liquid flows were countercurrent. Analyses of the amounts of S02and NH3 absorbed demonstrate that the hollow fiber unit has a relatively small membrane resistance and is an effective gas scrubbing device. Additionally, it offers a large interfacial area per unit volume, and avoids flooding problems entirely 相似文献
94.
Ilhaam Al-Maskery Kathryn Girling S. David Jackson Lynsey Pugh Ron R. Spence 《Topics in Catalysis》2010,53(15-18):1163-1165
The isomerisation of allylbenzene, dimethoxyallylbenzene (4-allyl-1,2-dimethoxybenzene), eugenol (2-methoxy-4-(2-propenyl)phenol), and estragole (4-allylanisole) into their respective cis/trans internal alkenyl aromatics has been studied over a supported solid base catalysts (K2CO3/alumina). The catalyst was active at 305 K with conversions as high as 36%. However all reactants cause deactivation of the catalyst. 相似文献
95.
Heather F. Jackson Daniel D. Jayaseelan William E. Lee Michael J. Reece Fawad Inam Dario Manara Carlo Perinetti Casoni Franck De Bruycker Konstantinos Boboridis 《International Journal of Applied Ceramic Technology》2010,7(3):316-326
Melting temperatures of zirconium carbide were investigated in validating a novel thermal analysis technique for refractory materials. Commercial ZrC0.96 powder was densified by spark plasma sintering to >96% relative density after 6–30 min at 2173–2453 K under 40–100 MPa. Sintered ceramics were heated to >4000 K via pulsed laser heating. Mean values for solidus and liquidus transitions were 3451 and 3608 K, respectively, in fair agreement with the present phase diagram. Postmelting analysis revealed dendritic microstructure and composition consistent with single-phase ZrC. Subsurface gas porosity and ZrC–C eutectic indicate complex processes occurring during melting and freezing. 相似文献
96.
The synthesis and in vitro biological evaluation (JEG-3 cells) of a series of novel and potent aromatase inhibitors, prepared by microwave-enhanced Suzuki cross-coupling methodology, are reported. These compounds possess a biphenyl template incorporated with the haem-ligating triazolylmethyl moiety, either on its own or in combination with other substituent(s) at various positions on the phenyl rings. The most potent aromatase inhibitor reported herein has an IC(50) value of 0.12 nM, although seven of its congeners are also highly potent (IC(50)相似文献
97.
The formation of active species for oxidative dehydrogenation of propane on magnesium molybdates 总被引:1,自引:0,他引:1
James E. Miller Nancy B. Jackson Lindsey Evans Allen G. Sault Mary M. Gonzales 《Catalysis Letters》1999,58(2-3):147-152
Pure and mixed magnesium molybdate phases (MoO3, MgMoO4, and MgMo2O7) have been examined for the oxidative dehydrogenation reaction of propane. The results are very sensitive to the stoichiometry and method of preparation. The catalysts exhibiting superior activity and selectivity are characterized by a unique temperature-programmed reduction peak that is not present for the poorly active or selective catalysts. Mixtures of MgMoO4 and MoO3 or MgMoO4 and MgMo2O7, materials that perform poorly by themselves, show significant improvements in performance upon heating. The solid-state interactions leading to these improvements correspond to the appearance of the characteristic reduction peak. The results suggest that the beneficial synergistic effects seen with mixtures of inactive phases are due to formation of a new phase or species, rather than remote communication between phases (e.g., oxygen spillover). This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
98.
Considerable work has been carried out on overlay bond coats in the past several decades because of its excellent oxidation resistance and good adhesion between the top coat and superalloy substrate in the thermal barrier coating systems. Previous studies mainly focus on oxidation and diffusion behavior of these coatings. However, the mechanical behavior and the dominant fracture and deformation mechanisms of the overlay bond coats at different temperatures are still under investigation. Direct comparison between individual studies has not yet been achieved due to the fragmentary data on deposition processes, microstructure and, more apparently, the difficulty in accurately measuring the mechanical properties of thin coatings. One of the miniaturized specimen testing methods, small punch testing, appears to have the potential to provide such mechanical property measurements for thin coatings. The purpose of this paper is to give an overview of using small punch testing to evaluate material properties and to summarize the available mechanical properties that include the ductile-to-brittle transition and creep of MCrAlY bond coat alloys, in an attempt to understand the mechanical behavior of MCrAlY coatings over a broad temperature range. 相似文献
99.
Alan L. Chaffee Galinda Lay Marc Marshall W. Roy Jackson Yi Fei T. Vincent Verheyen Steven G. Scott 《Fuel》2010,89(11):3241-3249
The structure of a suite of high-volatile, bituminous Surat Basin, Queensland coals has been investigated by a combination of analytical probes. These included elemental analyses, pyrolysis-gas chromatography-mass spectroscopy and Fourier transform infrared spectroscopy, together with a study of their liquefaction products in both tetralin and solvent free-tin catalysed hydrogenations. Samples were gathered across a 300 m depth interval intersected by the sampling well. Most techniques revealed clear but subtle differences in structure as a function of depth. The oils produced by solvent free-tin catalysed hydrogenation, however, showed very distinct dependence with depth and the waxy content, as indicated by 1H-NMR, could be correlated with the coal seam gas content. 相似文献
100.
Felipe A. Perdomo Siti H. Khalit Claire S. Adjiman Amparo Galindo George Jackson 《American Institute of Chemical Engineers》2021,67(3):e17194
The SAFT-γ Mie group-contribution equation of state is used to represent the fluid-phase behavior of aqueous solutions of a variety of linear, branched, and cyclic amines. New group interactions are developed in order to model the mixtures of interest, including the like and unlike interactions between alkyl primary, secondary, and tertiary amine groups (NH2, NH, N), cyclic secondary and tertiary amine groups (cNH, cN), and cyclic methine-amine groups (cCHNH, cCHN) with water (H2O). The group-interaction parameters are estimated from appropriate experimental thermodynamic data for pure amines and selected mixtures. By taking advantage of the group-contribution nature of the method, one can describe the fluid-phase behavior of mixtures of molecules comprising those groups over broad ranges of temperature, pressure, and composition. A number of aqueous solutions of amines are studied including linear, branched aliphatic, and cyclic amines. Liquid–liquid equilibria (LLE) bounded by lower critical solution temperatures (LCSTs) have been reported experimentally and are reproduced here with the SAFT-γ Mie approach. The main feature of the approach is the ability not only to represent accurately the experimental data employed in the parameter estimation, but also to predict the vapor–liquid, liquid–liquid, and vapor–liquid–liquid equilibria, and LCSTs with the same set of parameters. Pure compound and binary phase diagrams of diverse types of amines and their aqueous solutions are assessed in order to demonstrate the main features of the thermodynamic and fluid-phase behavior. 相似文献