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61.
Raj Kumar 《Colloid and polymer science》1979,257(1):95-97
Summary Estimation of zeta potential from experimental data on electroosmotic and electrophoretic effects for Zeokarb 225 (Na+ form)/methanol-water system has been made and discussed. Results indicate that zeta potentials estimated from electroosmotic flux and electrophoretic mobility are not in agreement and vary with applied potential difference in a linear manner. Reasons for the variation of zeta potential with electrical field have been discussed. It has been argued that zeta potentials estimated from electroosmotic data are more reliable in comparison to the values obtained from electrophoretic data.With 2 figures and 2 tables 相似文献
62.
Andrzej Czarnecki A. N. Kamal Qiping Xu 《Zeitschrift fur Physik C Particles and Fields》1992,54(3):411-417
We have analysed the recent data onD→ππ and \(K\bar K\) decays from ARGUS, CLEO and E691. (i) We find that Bauer, Stech and Wirbel (BSW) model does fairly well in explaining all data if we assume that final state interactions simply rotate the amplitudes in the complex plane. However, to get a good fit one needs to raiseD→K transition amplitudes by (5–10)% over the BSW values and lowerD→π amplitudes by a similar amount. (ii) We show that all the data can also be understood in a coupled channel inelastic model. (iii) We also find that the Isgur, Scora, Grinstein and Wise (ISGW) model-form factors, if extrapolated to small momentum transfers (t) by a single pole formula, yield branching ratios too small in comparison to data. We propose an alternate scheme to interpolate between BSW form factors att=0 and ISGW form factors att=t max. 相似文献
63.
64.
We propose a Veneziano-like model for VV reactions near threshold involving exchanges of 0– trajectories int- andu-channels. The model is applied to , , , and processes. The model in its simplest form cannot account for the disparities in the cross sections for
andK
*+
K
*– and for 00 and +–. Further refinements of the model are suggested. 相似文献
65.
The adsorption behavior and differential pulse cathodic adsorptive stripping voltammetry of the pesticide Chlorpyrifos (CP)
were investigated at the hanging mercury drop electrode (HMDE). The pesticide was accumulated at the HMDE and a well-defined
stripping peak was obtained at –1.2 V vs Ag/AgCl electrode at pH 7.50. A voltammetric procedure was developed for the trace
determination of Chlorpyrifos using differential pulse cathodic adsorptive stripping voltammetry (DP-CASV). The optimum working
conditions for the determination of the compound were established. The peak current was linear over the concentration range
9.90 × 10–8– 5.96 × 10–7 mol/L of Chlorpyrifos. The influence of diverse ions and some other pesticides was investigated. The analysis of Chlorpyrifos
in commercial formulations and treated waste water was carried out satisfactorily
Received: 10 July 1997 / Revised: 1 April 1998 / Accepted: 6 April 1998 相似文献
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Osman Ayop Mohamad Kamal A. Rahim Noor Asniza Murad Huda A. Majid 《Applied Physics A: Materials Science & Processing》2014,117(2):651-656
This paper presents the analysis of circular ring metamaterial absorber with the existing of copper lines. The structure is designed using lossy FR4 substrate with thin copper layers. The circular ring shape with copper lines is printed on the top surface of FR4 substrate, while at the bottom surface is printed with full copper ground plane. Parametric study is done to investigate the effect of copper lines on the resonance frequency. From the simulation, the circular ring metamaterial absorber with vertical copper lines can resonates at lower frequency, but this structure is polarized sensitive. This drawback can be improved by adding horizontal copper lines together with the vertical copper lines. The circular ring structure with vertical and horizontal copper lines is not only polarization insensitive, but it can works at wide operating angle of incident waves. 相似文献