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111.
A simple and rapid method is described for the estimation of the rubidium in coconut palm leaves by neutron activation analysis.
The method is found suitable for the estimation of stable Rb used as a tracer in root distribution studies. The average of
five determinations is 5.15 μg, which varies between 5.07 μg and 5.26 μg at 95% confidence limit. 相似文献
112.
A short survey on the development of the radioanalytical chemistry in India, including 130 references is given. 相似文献
113.
A. Haldar R. Martinez-Flores H. Katkhuda 《Theoretical and Applied Fracture Mechanics》2008,50(1):74-80
Crack detection is existing structures using measured dynamic response information is presented in this paper. The general area of health assessment of existing structures in the presence of uncertainty in modeling the structure, characteristics of sensors, and the dynamic response information collected by the sensors is emphasized. A time domain system identification-based procedure is proposed to assess health of a structure at the finite element level in the presence of all major sources of uncertainty. It is denoted as the GILS-EKF-UI method. The method does not require information on excitation that caused the response and the noise-contaminated response information needs not be available at all dynamic degrees of freedom. The method is verified using computer generated analytical and actual measured response information emphasizing three items: (1) identification of the defect-free frame, (2) detection of location of a crack accurately within a defective element, and (3) detection of a crack using limited response information using the GILS-EKF-UI method. 相似文献
114.
Pranab Sarkar 《Pramana》2001,56(4):537-543
We have calculated pure rotational transitions of water molecule from a kinetic energy operator (KEO) with the z-axis perpendicular to the molecular plane. We have used rotational basis functions which are linear combinations of symmetric
top functions so that all matrix elements are real. The calculated spectra agree well with the observed values. 相似文献
115.
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117.
Homopolymer of decyl acrylate (D) was synthesised, characterised (Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance (NMR)) and evaluated for its additive performance as antiwear (AW), pour point depressant (PPD) and viscosity modifier (VM). Physical blends of the polymer were also made with three different types of liquid crystals (each containing three samples), evaluated and the results were compared. The study indicated that additive performances (AW, VM and PPD) of the blended composites were much better in comparison to the homopolymer of polydecyl acrylates. 相似文献
118.
Nilay K. Pramanik Ramsankar Haldar Utpal K. Niyogi MD. Sarwar Alam 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(4):296-307
The non-isothermal crystallization kinetics was studied by differential scanning calorimetric analysis on nylon 66 and e-beam irradiated nylon 66 at different cooling rates. The Modified Avrami equation, the Ozawa equation and the Combined Avrami-Ozawa equation were applied to study the kinetics of non-isothermal crystallization of nylon 66. The crystallization behavior of pristine nylon 66 polymer was compared with that of e-beam irradiated nylon 66 and observed that the kinetics of non-isothermal crystallization of nylon66 was affected largely upon e-beam irradiation. E-beam irradiation not only decreased the crystallization temperature of nylon 66, but influenced the mechanism of nucleation and crystal growth and reduced the overall crystallization rate of nylon 66 also. The crystallization activation energy calculated by the Kissinger method for irradiated nylon 66 was lower than that of pristine nylon 66. 相似文献
119.
120.
Pranab K. Mukhopadhyay J. George S. K. Sharma K. Ranganathan T. P. S. Nathan 《Optics & Laser Technology》2002,34(5)
A practical method is described and used for determination of the effective stimulated emission cross-section (σe) in an operating diode pumped Nd:YVO4 micro-laser at 1064 nm with various doping concentrations. In this method a micro-laser is formed by keeping a small piece of the sample in a plane–plane resonator under semi-monolithic configuration and a fiber coupled diode laser (808 nm) was used for pumping. The pump power induced thermal lensing effect was used to make the cavity stable. In thermally stabilized solid-state lasers the cavity parameters change dynamically with the pump power and hence the overlap integrals become a function of the absorbed pump power. In our method the overlap integrals were estimated by measuring the thermal lens focal length at the threshold. The value of σe of Nd:YVO4 crystal with different doping concentrations obtained by this method were in well agreement with the reported values. 相似文献