Ultra lowq a discharge experiments in the SINP tokamak

Operation of most tokamaks in limited byq _a, the edge safety factor, which is usually about 2–3. In the SINP tokamak we have been able to obtain discharges withq _a values as low as 0·8. In this paper we describe our results on the setting up processes and the MHD activity associated with these ultra lowq _a discharges.     

Synthesis of new heterocondensed pteridines

Reaction of 2-aminopyrazine 1 with isothiocyanate, isocyanate or dithioketal reagent furnished pteridines 3,4 in good yield. Thioxo compound 3a was chlorinated, methylated and subsequently displaced by amines. A simple one-step synthesis of heterocondensed pteridines 8–13 by reaction of 2-aminopyrazine with various imino thioacetals was described 8–13 .     

Fluorescence from relaxed and unrelaxed excited state of benzil

This note reports the detection of fluorescence from unrelaxed S₁ state of benzil using Boxcar gating technique. The new emission exhibits mirror image relationship with absorption and blue shift in hydroxylic solvent. In order to ascertain wheter geometrical relaxation occurs in S₁ state, intensities of fluorescence from relaxed and unrelaxed state have been compared at various temperatures.     

Shell model yrast states of the N=83 nucleus 150Ho

Studies of delayed γ-rays from the reactions ¹²²Te(³²S, p3n) and ¹²¹Sb(³²S, 3n) have located high-spin excitations in ¹⁵⁰Ho up to a 92 ± 8 ns isomer at 2625 keV. The main yrast level sequence is found to agree closely with shell model predictions (based on an inert ¹⁴⁶Gd core) of level energies, isomeric half-life and deexcitation pathway for the $\text{(πh}{}_{\mathrm{<mtext>11</mtext><mtext>2</mtext>}}\text{)}{}^3\text{vf}{}_{\mathrm{<mtext>7</mtext><mtext>2</mtext>}}$ configuration.     

Influence of alloy composition on the dependence of the diffusivity-mobility ratio in ternary semiconductors on a quantizing magnetic field

An expression is derived for the diffusivity-mobility ratio in degenerate narrow-gap ternary semiconductors in the presence of a quantizing magnetic field. With the help of this expression, the diffusivity-mobility ratio is shown, taking n-Hg_1–xCd_xTe as an example, to have an oscillatory dependence on a quantizing magnetic field. The influence of alloy composition on such dependence is also investigated.     

First synthesis of lower-rim-substituted aryl ethers of p-tert-butylcalix[4]arene

With the use of S(N)Ar or Ullmann reactions, the synthesis of the first lower-rim aryl ether derivatives of tert-butylcalix[4]arene is reported, as are some of their conformational properties, (1)H NMR spectra, and X-ray crystal structures. The lower-rim aryl pendants reported herein provide for new scaffolds upon which a host of other new molecular architectures can be constructed, thus extending the capability of the versatile calix[4]arenes even further.     

A Highly Sensitive Nonenzymatic Glucose Sensor Based on Carbon Electrode Amplified with PdxCuy Catalyst

Approximately global Pd and Pd₉₄Cu₆ alloy nano catalysts of average diameter 10.5 and 5.9 nm respectively, have been synthesized hydrothermally by wet chemical reduction and co-reduction methods without addition of any capping agent. X-ray diffraction and various microscopic studies are used to characterize the crystal phase and the morphology of the catalysts. Non-enzymatic amperometric glucose sensors based on these synthesized catalyst materials are tested and compared in alkali at different potentials by cyclic voltammetry and chronoamperometry. The sensors characterized by fixed potential chronoamperometry are found to be sufficiently sensitive to glucose at different negative potentials like −0.65 V, −0.40 V, −0.10 V with respect to Hg/HgO electrode (E⁰≈0.1 V), where the reactions of glucose oxidation are different. The sensor constructed with Pd₉₄Cu₆ nanocatalyst shows an outstanding sensitivity of 10.1 mA cm⁻² mM⁻¹ which is considerably higher than that constructed with similarly synthesized Pd nanoparticles at any potential and that found in the literature of Pd based glucose sensors. The lower detection limit and response time obtained with Pd₉₄Cu₆ nanoparticles are 10 μM and 3 s respectively. These sensors also exhibit high specificity to glucose and significant anti-interference property against some common species like ascorbic acid (AA), uric acid (UA) and some monosaccharides whose interfering effects are found to decrease with decrease of potential of glucose oxidation. The electrocatalytic ability of the synthesized Pd and Pd₉₄Cu₆ nanoparticles toward glucose oxidation has also found promising in blood sample at different potentials.     

Application of Pomegranate by-Products in Muscle Foods: Oxidative Indices,Colour Stability,Shelf Life and Health Benefits

In recent years, considerable importance is given to the use of agrifood wastes as they contain several groups of substances that are useful for development of functional foods. As muscle foods are prone to lipid and protein oxidation and perishable in nature, the industry is in constant search of synthetic free additives that help in retarding the oxidation process, leading to the development of healthier and shelf stable products. The by-products or residues of pomegranate fruit (seeds, pomace, and peel) are reported to contain bioactive compounds, including phenolic and polyphenolic compounds, dietary fibre, complex polysaccharides, minerals, vitamins, etc. Such compounds extracted from the by-products of pomegranate can be used as functional ingredients or food additives to harness the antioxidant, antimicrobial potential, or as substitutes for fat, and protein in various muscle food products. Besides, these natural additives are reported to improve the quality, safety, and extend the shelf life of different types of food products, including meat and fish. Although studies on application of pomegranate by-products on various foods are available, their effect on the physicochemical, oxidative changes, microbial, colour stabilizing, sensory acceptability, and shelf life of muscle foods are not comprehensively discussed previously. In this review, we vividly discuss these issues, and highlight the benefits of pomegranate by-products and their phenolic composition on human health.