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171.
172.
173.
174.
J Santhanalakshmi G Shantha Lakshmi V K Aswal P S Goyal 《Journal of Chemical Sciences》2001,113(1):55-62
Small angle neutron scattering (SANS) measurements of D2O solutions (0.1 M) of sodium cholate (NaC) and sodium deoxycholate (NaDC) were carried out atT= 298 K. Under compositions very much above the critical micelle concentration (CMC), the bile salt micelle size growths were
monitored by adopting Hayter-Penfold type analysis of the scattering data. NaC and NaDC solutions show presence of correlation
peaks atQ = 0.12 and 0.1 ?-1 respectively. Monodisperse ellipsoids of the micelles produce best fits. For NaC and NaDC systems, aggregation number (9.0,
16.0), fraction of the free counterions per micelle (0.79, 0.62), semi-minor (8.0 ?) and semi-major axes (18.4, 31.7 ?) values
for the micelles were deduced. Extent of micellar growth was studied using ESR correlation time measurements on a suitable
probe incorporating NaC and NaDC micelles. The growth parameter (axial ratio) values were found to be 2.3 and 4.0 for NaC
and NaDC systems respectively. The values agree with those of SANS. 相似文献
175.
V. K. Aswal J. V. Joshi P. S. Goyal Rajesh Patel R. V. Upadhyay R. V. Mehta 《Pramana》2004,63(2):285-290
Small-angle neutron scattering studies have been carried out to check the structural integrity of citryltrimethylammonium
bromide (CTABr) micelles in a magnetic fluid for different magnetic fluid concentrations at two different temperatures 303
and 333 K. It is found that the CTABr micelles grow with increasing magnetic fluid concentration and there is a decrease in
the micellar size with increase in temperature. 相似文献
176.
In this paper we consider experimental situations requiring usage of a row-column design where v treatments are to be applied to experimental units arranged in b
1 rows and b
2 columns where row i has size k
1i
, i=1,..., b
1 and column j has size k
2j
, j=1,..., b
2. Conditions analogous to those given in Kunert (1983, Ann. Statis., 11, 247–257) and Cheng (1978, Ann. Statist., 6, 1262–1272) are given which can often be used to establish the optimality of a given row-column design from the optimality of an associated block design. In addition, sufficient conditions are derived which guarantee the existence of an optimal row-column design which can be constructed by appropriately arranging treatments within blocks of an optimal block design.Visiting from the Indian Statistical Institute. 相似文献
177.
Sara M. Resnizky Rita R. Plá Raquel C. Jasan Sonia E. Hevia Mónica A. Moreno Rodrigo Invenizzi 《Accreditation and quality assurance》2006,10(11):590-593
The implementation of a quality system based on the ISO/IEC 17025:1999 standard is a growing necessity for analytical laboratories to demonstrate their technical competence. In 2001, the Nuclear Analytical Techniques Group of the Argentine Atomic Energy Commission obtained the recognition of the International Atomic Energy Agency in the application of neutron activation analysis and the accreditation by the national accreditation body. The importance of the participation of the group in the Agency's Regional Programme for Latin America, ARCAL XXVI on Quality Assurance in Analytical laboratories is discussed, as well as the activities performed to attain these objectives. Some improvements worth mentioning resulted from the implementation of the quality system and, following the premise of continuous improvement, changes were introduced aiming at the laboratory re-accreditation. 相似文献
178.
U. Wahl J. G. Correia E. Rita E. Alves J. C. Soares B. De Vries V. Matias A. Vantomme 《Hyperfine Interactions》2004,159(1-4):363-372
We present results of recent emission channeling experiments on the lattice location of implanted Fe and rare earths in wurtzite
GaN and ZnO. In both cases the majority of implanted atoms are found on substitutional cation sites. The root mean square
displacements from the ideal substitutional Ga and Zn sites are given and the stability of the Fe and rare earth lattice location
against thermal annealing is discussed. 相似文献
179.
Micellar solutions are the suspension of the colloidal aggregates of the sur-factant molecules in aqueous solutions. The structure
(shape and size) and the interaction of these aggregates, referred to as micelles, depend on the molecular architecture of
the surfactant molecule, presence of additives and the solution conditions such as temperature, concentration etc. This paper
gives the usefulness of small-angle neutron scattering to the study of micellar solutions with some of our recent results. 相似文献
180.
In the present work, we introduce and study essentially a class of multi-dimensional modified fractional calculus operators
involving a general class of polynomials in the kernel. These operators are considered in the space of functionsM
γ
(R
+
n
). Some mapping properties and fractional differential formulas are obtained. Also images of some elementary and special functions
are established. 相似文献