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41.
Nicole Fietkau Fran?ois G Chevallier Li Jiang Timothy G J Jones Richard G Compton 《Chemphyschem》2006,7(10):2162-2167
The size of a glass sphere positioned in the center of a microdisk electrode is determined by using a simple electrochemical procedure and is confirmed, additionally, by a microscopical measurement of the sphere at the time of the electrochemical measurement. The cyclic voltammetric response of the naked electrode and of the electrode with the sphere positioned in its center is recorded over a wide range of scan rates (0.002-1.5 V s(-1)). The size of the sphere is then determined by comparison of the experimental voltammogram with simulations for each individual scan rate. 相似文献
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Paul Schaffer James F. Britten Alan Davison Alun G. Jones John F. Valliant 《Journal of organometallic chemistry》2003,680(1-2):323-328
Two homoleptic Re(I) complexes of ortho and para-carborane isocyanide ligands were prepared as the first examples of a new class of metal-based BNCT and BNCS agents. The target compounds were prepared in low yield through the reaction of [Re2(O2CPh)4Cl2] and [Re2(OAc)4Cl2] with 3-isocyano-1,2-dicarba-closo-dodecaborane and a para-carborane azetidine derivative respectively. The desired product from the latter reaction was characterized crystallographically and is only the second reported molecular structure of a homoleptic Re(I) isonitrile complex. 相似文献
45.
A. S. Paschoa M. Cholewa K. W. Jones N. P. Singh M. E. Wrenn 《Journal of Radioanalytical and Nuclear Chemistry》1987,115(2):231-240
A combination of two techniques, PIXE (particle induced x-ray emission) and RBS (Rutherford backscattering), is proposed as an analytical tool to measure uranium and thorium in environmental and biological samples and in the study of the micro-distribution of uranium is low Z matrices such as biological tissue.Work supported by U.S. Department of Energy Contracts DE-AC02-76CH-00116 (MC, KWJ) and DE-AC02-76EV-00119 (NPS, MEW). One of us (ASP) is grateful to FINEP (Financiadora de Estudos e Projetos) and CNPq (Conselho Nacional de Desenvolvimento Cientifico e Technológico). 相似文献
46.
Pyrolysis of homoadamant-3-ene (), generated from 1-adamantylcarbene (), leads to the same three olefins (, , and ) that are produced from pyrolysis of 3-homoadamantyl acetate (). 相似文献
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The interaction of an ultrasonic wave with a bubbly two-phase flow is studied both experimentally and theoretically. Brief theoretical reviews of acoustic wave generation by a piston and of the interaction of a plane wave with a single bubble are given. A theory relating ultrasonic wave transmission through a bubbly flow with two-phase flow parameters, notably the bubble size and the volumetric interfacial area, is derived and compared with preliminary data. The theoretical and experimental limitations concerning the application of ultrasonic transmission measurements to the study of bubbly flow are discussed in detail, and recommendations for future work in this area are made.Nomenclature
A
projected cross-sectional area of a bubble
-
a
bubble radius
-
a
T
emitter radius
-
c
speed of sound
-
d
equivalent bubble diameter
-
I
intensity
-
I
0
incident intensity
-
J
0
Bessel function of zero order
-
J
0
Bessel function of first order
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j
1
spherical Bessel function of the first kind and of order l
-
k
wave number
-
n
l
spherical Bessel function of the second kind (Nishi's notation)
-
n
number of bubbles per unit volume or per unit area
-
P
0
pressure amplitude at the emitter; equilibrium pressure in the liquid
-
p
pressure perturbation
-
r
spherical coordinate, radial distance to the x-axis
-
S
total scattering cross-sectional area, surface of the piston
-
S
i
scattering cross-sectional area of the i-th bubble
-
T
transmittance
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t
time
-
U
complex source strength divided by the source area
-
W
ratio of radial distance from the axis on the emitter surface to the radius of the emitter
-
x
axis coinciding with the direction of propagation of the plane wave; distance between the transducers
-
void fraction
-
interfacial area per unit volume
-
spherical coordinate
-
ultrasonic wavelength
-
density
-
angular frequency 相似文献