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81.
Iron-doped zircon: the mechanism of formation 总被引:1,自引:0,他引:1
Iron-doped zircon (zirconium silicate) has been prepared from silica, zirconia and iron(II) sulphate heptahydrate using a mixture of sodium halides and alkali metal nitrates as mineralisers to lower the temperature of reaction. The formation of a silicon- and fluorine-containing glassy phase in the reaction vessel, together with evidence for a SiF3 breakdown product and the analysis of solid phases formed at intermediate temperatures, implicate the participation of a volatile silicon fluoride intermediate, probably SiF4, in the formation of the iron-doped zircon. 相似文献
82.
Holloway L.E. Xiaoyi Guan Sundaravadivelu R. Ashley J. Jr. 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2000,30(5):696-712
Automated control synthesis methods for discrete-event systems promise to reduce the time required to develop, debug, and modify control software. Such methods must be able to translate high-level control goals into detailed sequences of actuation and sensing signals. In this paper, we present such a technique. It relies on analysis of a system model, defined as a set of interacting components, each represented as a form of condition system Petri net. Control logic modules, called taskblocks, are synthesized from these individual models. These then interact hierarchically and sequentially to drive the system through specified control goals. The resulting controller is automatically converted to executable control code. The paper concludes with a discussion of a set of software tools developed to demonstrate the techniques on a small manufacturing system 相似文献
83.
Effects of reinforced concrete structures on RF communications 总被引:3,自引:0,他引:3
Dalke R.A. Holloway C.L. McKenna P. Johansson M. Ali A.S. 《Electromagnetic Compatibility, IEEE Transactions on》2000,42(4):486-496
The proliferation of communication systems used in and around man-made structures has resulted in a growing need to determine the reflection and transmission properties of various commonly used building materials at radio frequencies typically used in businesses and residential environments. This paper describes the calculation of reflection and transmission coefficients for reinforced concrete walls as a function of wall thicknesses and rebar lattice configuration over a frequency range of 100-6000 MHz. The transmission and reflection coefficients were calculated using a finite-difference time-domain (FDTD) solution of Maxwell's equations. The rebar structures analyzed include both a two-dimensional (2-D) trellis-like structure and a one-dimensional (1-D) structure, where the reenforcing bars are all oriented in the same direction. In general, the results show that the reinforced concrete structures severely attenuate signals with wavelengths that are much larger than the rebar lattice and that the transmitted signal has a complex structure with resonances and nulls that strongly depend upon the geometry of the reinforcing structure and the concrete wall thickness 相似文献
84.
William Holloway Xiaolong Yin Sankaran Sundaresan 《American Institute of Chemical Engineers》2010,56(8):1995-2004
In this article, we extend the low Reynolds number fluid‐particle drag relation proposed by Yin and Sundaresan for polydisperse systems to include the effect of moderate fluid inertia. The proposed model captures the fluid‐particle drag results obtained from lattice‐Boltzmann simulations of bidisperse and ternary suspensions at particle mixture Reynolds numbers ranging from 0 ≤ Remix ≤ 40, over a particle volume fraction range of 0.2 ≤ ? ≤ 0.4, volume fraction ratios of 1 ≤ ?i/?j ≤ 3, and particle diameter ratios of 1 ≤ di/dj ≤ 2.5. © 2009 American Institute of Chemical Engineers AIChE J, 2010 相似文献
85.
Mundle R Holloway T Zhang K Bahoura M Pradhan AK 《Journal of nanoscience and nanotechnology》2012,12(5):3938-3942
The electric and Kelvin force probe microscopy were used to investigate the surface potentials on the ZnO seed layer, which shows a remarkable dependence on the annealing temperature. The optimum temperature for the growth of nanorod arrays normal to the surface was found to be at 600 degrees C, which is in the range of right surface potentials and energy measured between 500 degrees C and 700 degrees C. We demonstrated from both electric and Kelvin force probe microscopy studies that surface potential controls the growth of ZnO nanorods, illustrating the fact that this is a promising technique to visualize the control of ZnO nanorod arrays by studying their surface potentials. This study will provide important understanding of growth of other nanostructures. 相似文献
86.
Gulab N. Jham Bryan R. Moser Shailesh N. Shah Ronald A. Holser Onkar D. Dhingra Steven F. Vaughn Mark A. Berhow Jill K. Winkler-Moser Terry A. Isbell Ray K. Holloway Erin L. Walter Ricardo Natalino Jason C. Anderson David M. Stelly 《Journal of the American Oil Chemists' Society》2009,86(9):917-926
Wild mustard (Brassica juncea L.) oil is evaluated as a feedstock for biodiesel production. Biodiesel was obtained in 94 wt.% yield by a standard transesterification
procedure with methanol and sodium methoxide catalyst. Wild mustard oil had a high content of erucic (13(Z)-docosenoic; 45.7 wt.%) acid, with linoleic (9(Z),12(Z)-octadecadienoic; 14.2 wt.%) and linolenic (9(Z),12(Z),15(Z)-octadecatrienoic; 13.0 wt.%) acids comprising most of the remaining fatty acid profile. The cetane number, kinematic viscosity,
and oxidative stability (Rancimat method) of the methyl esters was 61.1, 5.33 mm2 s−1 (40 °C) and 4.8 h (110 °C), respectively. The cloud, pour and cold filter plugging points were 4, −21 and −3 °C, respectively.
Other properties such as acid value, lubricity, free and total glycerol content, iodine value, Gardner color, specific gravity,
as well as sulfur and phosphorous contents were also determined and are discussed in light of biodiesel standards ASTM D6751
and EN 14214. Also reported are the properties and composition of wild mustard oil, along with identification of wild mustard
collected in Brazil as Brassica juncea L. (2n = 36) as opposed to the currently accepted Sinapis arvensis L. (2n = 18) classification. In summary, wild mustard oil appears to be an acceptable feedstock for biodiesel production.
Disclaimer: Product names are necessary to report factually on available data; however, the USDA neither guarantees nor warrants
the standard of the product, and the use of the name by USDA implies no approval of the product to the exclusion of others
that may also be suitable. 相似文献
87.
Holloway Kevin S.; Balthazart Jacques; Cornil Charlotte A. 《Canadian Metallurgical Quarterly》2005,119(1):49
Demonstrations of increased reproductive success due to sexual conditioning in Japanese quail (Coturnix japonica) have been reported, although the mechanisms that underlie these effects have remained elusive. One possible mechanism is conditioned rhythmic cloacal sphincter movements (RCSM). Two experiments were conducted with male quail to determine whether associations between a conditioned stimulus (CS) and a hen would result in the ability of the CS to elicit RCSM, and to explore the androgen mediation of conditioned RCSM. The results suggest that a focal CS paired with visual access to a female will elicit RCSM via a representation of the hen activated by the CS. Further, the available evidence indicates that conditioned RCSM is androgen mediated and that this learning may transfer across breeding seasons. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
88.
Miville Marie L.; Gelso Charles J.; Pannu Raji; Liu Will; Touradji Pegah; Holloway Pauline; Fuertes Jairo 《Canadian Metallurgical Quarterly》1999,46(3):291
Universal-diverse orientation was defined as an attitude of awareness and acceptance of both the similarities and differences that exist among people. A 45-item scale developed to measure the construct was administered to 4 separate samples (ns?=? 93, 111, 153, and 135). Internal consistency and retest reliability for the Miville-Guzman Universality-Diversity Scale (M-GUDS) ranged from .89 to .95. The M-GUDS significantly correlated in theoretically predicted ways with measures of racial identity, empathy, healthy narcissism, feminism, androgyny, homophobia, and dogmatism (the last 2 correlations were negative). The M-GUDS displayed discriminant validity by failing to correlated with Scholastic Achievement Test Verbal Scores, although mixed results were obtained with social desirability. In summary, the data suggest considerable reliability and initial construct validity for the M-GUDS. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
89.
A prototype solid-state, multispectral hybrid laser has been designed and tested. The laser provides simultaneous outputs at several wavelengths. The hybrid-laser concept is based on the efficient use of flash-lamp-pump energy distributed between two complementary lasing materials, Nd:YAG and Cr:LiSAF, that share the same pump cavity. The prototype Q-switched hybrid laser provides dual-fundamental-wavelength output at 850 and 1064 nm as well as frequency-doubled output at 532 nm. The laser achieved 3.6% slope efficiency (combined) in free-running operation and 2.4% when Q switched. Higher efficiencies can be obtained with improvements in laser crystal quality and pump cavity configuration. 相似文献
90.