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41.
Empirical formula suggested by Kita and Koizumi for evaluation of relaxation intensity in a limited range of frequency around
the relaxation frequency for the Cole-Cole type distribution has been tested for poly butyl acrylate (PBA), Poly butyl methacrylate
(PBMA) and poly isobutyl methacrylate (PiBMA).
The relaxation intensity Δε is expressed in terms ofε″
M
, the dielectric loss maxima andW, the frequency separation for half, two thirds or three quarters ofε″
M
, in the form Δε=ε″
M
/[(C
1/W)+C
2+C
3
W], where the numerical constantsC
1,C
2,C
3 are given for the respective type of relaxation. 相似文献
42.
A. V. Varlamov T. N. Borisova S. B. Barge L. G. Voskresenskii A. I. Chernyshev E. M. Semenova 《Chemistry of Heterocyclic Compounds》1998,34(12):1418-1422
8-Substituted tetrahydropyrido[3,2-e]pyrrolizines are formed in the [3+2]-cycloaddition of 2-formyltetrahydropyrrolo[3,2-c]pyridine and acrolein, acrylonitrile, and methyl acrylate in the presence of trilon B.
Russian International Friendship University, 117923 Moscow. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12,
pp. 1670–1675, December, 1998. 相似文献
43.
44.
Aime S Barge A Batsanov AS Botta M Castelli DD Fedeli F Mortillaro A Parker D Puschmann H 《Chemical communications (Cambridge, England)》2002,(10):1120-1121
The rate of axial water exchange in well-defined series of lanthanide complexes depends on the extent of second sphere hydration which is determined by complex hydrophobicity and the nature of the lanthanide ion and its counter-ion. 相似文献
45.
This paper is devoted to the study of some aspects of the stability theory of flows. In particular, we study Morse decompositions induced by non-saddle sets, including their corresponding Morse equations, attractor-repeller splittings of non-saddle sets and bifurcations originated by implosions of the basin of attraction of asymptotically stable fixed points. We also characterize the non-saddle sets of the plane in terms of the Euler characteristic of their region of influence. 相似文献
46.
In this present work, for the first time, we are reporting a green synthesis approach for the preparation of vinyl modified reduced graphene oxide-based magnetic and bimetallic (Fe/Ag) nanodendrite (RGO@BMNDs). Herein, the RGO@BMNDs acts as a platform for the synthesis of the pyrazinamide (PZA)-imprinted polymer matrix and used for designing of the electrochemical sensor. We have demonstrated how the change in morphology could affect the electrochemical and magnetic property of nanomaterials and for this the reduced graphene oxide-based bimetallic nanoparticle (Fe/Ag) was also prepared It was found that the combination of graphene and bimetallic nanodendrites shows improvement as well as enhancement in the electrocatalytic activity and adsorption capacity, in comparison to their respective nanoparticles. The application of imprinted-RGO@BMNDs sensor was explored for trace level detection of PZA (Limit of detection = 6.65 pg L−1, S/N = 3), which is a drug used for the cure of Tuberculosis. This is lowest detection limit reported so far for the detection of PZA. The sensor is highly selective, cost-effective, simple and free from any interfering effect. The real time application of the sensor was explored by successful detection of PZA in pharmaceutical and human blood serum, plasma and urine samples. 相似文献
47.
48.
Jake R. Zimmerman Brian J. Myers Samantha Bouhall Allison McCarthy Olivia Johntony Madhuri Manpadi 《Tetrahedron letters》2014
In this study, we report a two-step, one pot tandem microwave-assisted reaction of 3-formylchromones with aminopyrazoles followed by a tin-free radical addition. A library of alkyl substituted dihydropyrazolopyrimidines was prepared using this new process. 相似文献
49.
Neeraj Mishra Niranjan Patra Sunil Pandey Marco Salerno Madhuri Sharon Maheshwar Sharon 《Journal of Thermal Analysis and Calorimetry》2014,117(2):885-892
Present research deals with the conversion of waste commodity plastics to valuable commercial product in the form of wax by pyrolysis. Optimization of both processes yield and produced wax quality was performed by means of a statistical tool originally proposed by G. Taguchi, using temperature, catalyst, carrier gas, and dwell time as the parameters. The obtained wax was characterized by Raman spectroscopy, differential scanning calorimetry, and thermogravimetric analysis. Yield of wax was found to be maximum when the parameters were 600 °C, Fe catalyst, nitrogen gas atmosphere, and 15 min time. However, stability of the wax was found to be optimum at 700 °C. Calorific value of the wax thus obtained was ~43 MJ kg?1, which supports its suitability as fuels like other petroleum products. 相似文献
50.
Substitution reactions of propyl cobaloxime with imidazole, substituted imidazoles, histidine, histamine, glycine and ethyl
glycine ester are carried out as a function of pH. Trends in the formation constants are explained based on the steric hindrance,
extent of π-bonding and Σ-donor capacity of the incoming ligand. Molecular mechanics is used to theoretically determine the
bond length and bond strain values by MM2 parametrization and these are correlated with the experimental data. 相似文献