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• Author or Editor: R. Nair
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## On Templeman averages and variation functions

Periodica Mathematica Hungarica
Author:
R. Nair

## Abstract

Let S be a countable semigroup acting in a measure-preserving fashion (gT g ) on a measure space (Ω, A, µ). For a finite subset A of S, let |A| denote its cardinality. Let (A k ) k=1 be a sequence of subsets of S satisfying conditions related to those in the ergodic theorem for semi-group actions of A. A. Tempelman. For A-measureable functions f on the measure space (Ω, A, μ) we form for k ≥ 1 the Templeman averages
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\pi _k (f)(x) = \left| {A_k } \right|^{ - 1} \sum\nolimits_{g \in A_k } {T_g f(x)}$$ \end{document}
and set V q f(x) = (Σ k≥1|π k+1(f)(x) − π k (f)(x)|q)1/q when q ∈ (1, 2]. We show that there exists C > 0 such that for all f in L 1(Ω, A, µ) we have µ({x ∈ Ω: V q f(x) > λ}) ≤ C(∫Ω | f | dµ/λ). Finally, some concrete examples are constructed.
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## Thermogravimetric analysis of PVC/NR-b-PU blends

Journal of Thermal Analysis and Calorimetry
Authors:
and
M. R. Gopinathan Nair

## Abstract

Thermal stability of solution-cast blends of poly(vinylchloride) and NR-b-PU block copolymers of three different chain extender diols was studied by thermogravimetry. Thermal degradation of individual components and their blends were investigated with special reference to blend ratio. As the block copolymer content in the blends increased their thermal stability was also found to increase. Enhanced thermal stability of PVC is believed due to the favorable interaction with PVC and the PU hard segments of the block copolymer. DTG curves were used for the determination of different stages involved in the degradation. Activation energy for degradation was determined from Coats–Redfern plot.

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## Radioimmunoassay for individual lactate dehydrogenase isoenzymes 1 and 2

Journal of Radioanalytical and Nuclear Chemistry
Authors:
M. Menon
,
G. Nambiar
, and
R. Nair

## Abstract

Radioimmunoassays (RIA) for the determination of the individual lactate dehydrogenase (LDH) isoenzymes, LDH-1 and LDH-2 have been developed. LDH-1 can be measured in the range of 5–100 ng and LDH-2 in the range of 5–80 ng, if there is no significant cross reactivity. Immunization of several rabbits with LDH-1 and LDH-2 isoenzymes reveals that some animals do not produce antisera to LDH-2 while those injected with LDH-1 generated antiserum in each case. The results of the binding studies suggest that a 50% binding that is recommended for RIA can be achieved with a titer value of 12000 dilution of the antisera. Cross reactivity studies indicate that LDH-1 cross reacts with the antisera to LDH-2 if its concentration is higher than 30 ng/ml of the RIA mixture while LDH-2 cross reacts with the antisera to LDH-1 only if its concentration exceeds 80 ng/ml.

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## Speciation and instrumental neutron activation analysis for arsenic in water samples

Journal of Radioanalytical and Nuclear Chemistry
Authors:
R. Acharya
,
A. Nair
, and
A. Reddy

## Abstract

Ground water samples obtained from West Bengal, India were analyzed for total arsenic and its inorganic species contents by instrumental neutron activation analysis (INAA). Two anion exchange separation methods using Dowex 1X8 in chloride and acetate forms were standardized for the speciation of As(III) and As(V) using radiotracers. The method by Dowex 1X8 in the acetate form was validated using synthetic mixtures of As(III) and As(V), and applied to water samples; the species concentrations were determined by INAA. The accuracy of the INAA method was evaluated by analyzing the NRCC CRM DORM-2 for total arsenic.

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## On theC p toC v conversion of solid linear macromolecules II

Journal of Thermal Analysis and Calorimetry
Authors:
R. Pan
,
Manika Nair
, and
B. Wunderlich
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## Estimation of thorium intake due to consumption of vegetables by inhabitants of high background radiation area by INAA

Journal of Radioanalytical and Nuclear Chemistry
Authors:
R. Sathyapriya
,
Suma Nair
,
V. Kamesh
,
R. Prabhath
,
,
R. Acharya
, and
D. Rao

## Abstract

A study was conducted to estimate the thorium concentration in locally grown vegetables in high background radiation area (HBRA) of southern coastal regions of India. Locally grown vegetables were collected from HBRA of southern coastal regions of India. Thorium concentration was quantified using instrumental neutron activation analysis. The samples were irradiated at CIRUS reactor and counted using a 40% relative efficiency HPGe detector coupled to MCA. The annual intake of thorium was evaluated using the consumption data provided by National Nutrition Monitoring Board. The daily intake of 232Th from the four food categories (green leafy vegetables, others vegetables, roots and tubers, and fruits) ranged between 0.27 and 5.352 mBq d−1. The annual internal dose due to ingestion of thorium from these food categories was 46.8 × 10−8 for female and 58.6 × 10−8 Sv y−1 for male.

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## A computation scheme to evaluate debye and tarasov equations for heat capacity computation without numerical integration

Journal of Thermal Analysis and Calorimetry
Authors:
R. Pan
,
M. Varma-Nair
, and
B. Wunderlich
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## Availability of essential trace elements in medicinal herbs used for diabetes mellitus and their possible correlations

Journal of Radioanalytical and Nuclear Chemistry
Authors:
R. Choudhury
,
R. Acharya
,
A. Nair
,
A. Reddy
, and
A. Garg

## Abstract

Four plant parts (leaves, roots, fruits and seeds) of twenty samples of sixteen antidiabetic herbs including three commercially marketed capsules have been analyzed for 6 minor (Na, K, Ca, Cl, Mg, and P) and 21 trace (As, Ba, Br, Ce, Co, Cr, Cs, Cu, Eu, Fe, Hg, La, Mn, Rb, Sb, Sc, Se, Sm, Th, V and Zn) elements by instrumental neutron activation analysis (INAA). Further, Ni, Cd and Pb contents were determined by AAS. Elemental data were validated by simultaneously analyzing reference material (RM), MPH-2 Mixed Polish Herbs. Several elements such as Cr and V (1–2 μg/g), Rb (10–40 μg/g), Cs (80–300 ng/g), Se (∼100 ng/g) and Zn (25–60 μg/g) play an important role in diabetes mellitus. Interelemental linear correlations have been observed for Cu vs. Zn (r = 0.89) and Rb vs. Cs (r = 0.87). K/P ratio varies in a narrow range with a mean value of 6.2 ± 1.4. Toxic elements As and Hg were found in <1 μg/g whereas Cd and Pb were in ∼5 μg/g and <10 μg/g, respectively.

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## Multielement analysis of natural ruby samples by neutron activation using the single comparator method

Journal of Radioanalytical and Nuclear Chemistry
Authors:
R. Acharya
,
P. Burte
,
A. Nair
,
A. Reddy
, and
S. Manohar

## Abstract

Multielement analysis was carried out in two samples of natural rubies obtained from Kenya and Tanzania and a synthetic ruby obtained locally. The trace element profile was used to characterise the ruby samples. Instrumental Neutron Activation Analysis (INAA) by the single comparator (K 0 method) was used to determine the concentrations of 22 elements with gold as the comparator. High resolution -ray spectrometry was employed for radiometric assay of the activation products. The accuracy and precision were evaluated by analysing standard reference materials such as USGS-W-1 and AGV-1 and were found to be satisfactory.

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## A rapid and selective separation of palladium

Journal of Radioanalytical and Nuclear Chemistry
Authors:
A. Dakshinamoorthy
,
A. Nair
,
S. Das
,
R. Singh
, and
Satya Prakash

## Abstract

Palladium was separated from Al, Ru, Rh, U, Pu and also from a mixture of fission products using -benzoin-oxime as the extractant and Solvesso-100 as the diluent. The extraction is quantitative over a wide range of acidity from 0.1M to 4M HNO3. The method has been found to be equally effective to separate Pd at trace level (carrier-free form). The stoichiometry of the complex, the interference of foreign elements in Pd separation, etc., are reported. The applicability of the method to separate palladium formed in fission rapidly from all other fission products, especially the most strongly interfering molybdenum isotopes, and the recovery of this element from high level radioactive waste are also mentioned.

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