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61.
Reported herein is an example of a solution-state cross-coupling cyclization with an outcome mediated by perfluorophenyl-phenyl electrostatic interactions. 相似文献
62.
Grooved-dielectric, phase-correcting, Fresnel zone plate antennas are analyzed using the body-of-revolution finite-difference time-domain (BOR-FDTD) method. Parametric studies of the focusing ability of these antennas are performed to examine the effects of the focal length, diameter, number of zones, and the thickness of the lens, as well as the number of phase corrections per zone. The results of these studies are presented as design graphs and are used to lend insight into the focusing mechanism of phase-correcting zone plates. The BOR-FDTD analysis is validated by comparison with previous measurements. 相似文献
63.
Grainger Reid J. Ko Samuel Koslov Eugene Prokop Ales Tanner Robert D. Loha Veara 《Applied biochemistry and biotechnology》2000,84(1-9):761-768
Human insulin in zinc suspension was used as a model protein to test the effect of shear on the settling rate of proteins,
a possible inference for protein denaturation. The rate of settling was determined directly in a spectropho-tometer. Shear
effects are important in retaining the activity of proteins and are present in bubble, foam, and droplet protein fractionation
processes. A sim pletest, such as that conducted here, mayeven be useful for monitoring changes in protein structure caused
by commercial shipping of the protein. The settling ratefor insulin was continously monitored in theoriginal bottle by spectrophotometric
absorbance changes as a function of time. A settling curve was determined following each shear experiment, which included
shaking the “worked” insulin solution in a vortex mixer for different lengths of time. It was determined, when comparing long
shaking times with short ones, that the initial settling rate was less for the long-term shaking of the insulin samples and
greater for the short-term shaking. The secondary effects of light and heat, along with shaking, a pparently did not produce
differences from shaking alone. 相似文献
64.
Ivan D. Reid Lap Y. Lee David M. Garner Donald J. Arseneau Masa Senba Donald G. Fleming 《Hyperfine Interactions》1986,32(1-4):801-806
This paper reports preliminary new measurements of the thermal reaction rate constants of muonium (Mu) with hydrogen and deuterium
gases in the range 480–675 K. From Arrhenius plots of the measured reaction rate constants new values of the pre-exponential
factors log10 (A) and activation energies Ea have been determined for these reactions, representing a significant improvement over earlier results. 相似文献
65.
Kean P.N. Smith K. Sinclair B.D. Sibbett W. Rowe C.J. Reid D.C.J. 《Electronics letters》1987,23(23):1241-1243
We have constructed a completely integrated fibre Raman oscillator using two fibre grating reflectors. This was synchronously mode-locked using a CW mode-locked Nd:YAG laser operating at 1.06?m. Spectral and temporal characteristics of the Raman oscillator are presented. 相似文献
66.
67.
E. Emmet Reid 《Analytical and bioanalytical chemistry》1921,60(9-10):369-369
68.
69.
70.
Patterned bandpass dielectric interference filters with centre wavelengths around 1.3 mu m have been applied to top-entry photodiodes to produce high-speed, high-responsivity, photodetectors for wavelength division multiplexing. The measured responsivity exceeded 25 A/W with a full width half maximum of 19 nm and peak rejection of over 25 dB.<> 相似文献