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61.
An instrumental neutron activation analytical (INAA) technique is described for the determination of 26 toxic and other trace elements in Eastern Coal (NBS SRM-1632a), local coal and its ash. The coal ash was produced by heating coal at 750°C in a muffled furnace. The transfer of these elements to the environment on the complete compustion of coal is estimated from the difference between the elemental concentration of coal and its ash.  相似文献   
62.
We report the absorption spectra of RDX and TNT explosive samples in solid form at room temperature using a carbon dioxide laser-based photo-acoustic technique. A continuous wave 12C16O2 laser, tunable between the 9.25–10.74 μm wavelength region, was used as an energy source. Interference-free limits of detection of solid RDX and TNT in simulated samples are estimated to be 10.0 and 16.5 ppbw, respectively. Published in Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 1, pp. 113–118, January–February, 2006.  相似文献   
63.
64.
The radiation effects using the Rosseland approximation on the flow of an incompressible viscous electrically conducting fluid over a stretching sheet near the stagnation point in the presence of uniform transverse magnetic field is studied. The governing equations transform to ordinary differential equation by using suitable similarity transformation and then by a perturbation technique the numerical results for temperature distribution were obtained and discussed graphically.  相似文献   
65.
In the present study, a novel p-phenylcarboxylic acid BODIPY ( L ) immobilized MCM-41 based solid chemosensor material L-propylsilyl@MCM-41 ( MS4 ) was developed to detect multiple metal ions in a pure aqueous medium. The synthesized solid chemosensor material MS4 shows high sensitivity and removal ability towards trivalent (Al3+, Cr3+) and divalent (Cu2+, Hg2+) metal ions. The emission intensity of MS4 enhanced multifold selectively in the presence of trivalent (Al3+, Cr3+) metal ions and shows quenching in the presence of divalent (Cu2+, Hg2+) metal ions. The limit of detection was calculated to be in the nanomolar range with Al3+, Cr3+, Cu2+, and Hg2+ metal ions in the aqueous medium. The spectroscopic and analytical results suggest that MS4 selectively binds with Al3+ and Cr3+ through −NH functionality and with Hg2+ and Cu2+ through −COOH functionality of p-phenylcarboxylic acid BODIPY ( L ). Further, MS4 selectively removes Al3+, Cr3+, Cu2+, and Hg2+ metal ions from the aqueous media with removal efficiency of 97.28 %, 96.34 %, 87.19 %, and 95.63 %, respectively. No noticeable change in the concentration was observed for other metal ions. The recycling potential of MS4 was evaluated using EDTA for up to seven cycles with no significant reduction in sensing capability.  相似文献   
66.
A sedentary lifestyle or lack of physical activity increases the risk of different diseases, including obesity, diabetes, heart diseases, certain types of cancers, and some neurological diseases. Physical exercise helps improve quality of life and reduces the risk of many diseases. Irisin, a hormone induced by exercise, is a fragmented product of FNDC5 (a cell membrane protein) and acts as a linkage between muscles and other tissues. Over the past decade, it has become clear that irisin is a molecular mimic of exercise and shows various beneficial effects, such as browning of adipocytes, modulation of metabolic processes, regulation of bone metabolism, and functioning of the nervous system. Irisin has a role in carcinogenesis; numerous studies have shown its impact on migration, invasion, and proliferation of cancer cells. The receptor of irisin is not completely known; however, in some tissues it probably acts via a specific class of integrin receptors. Here, we review research from the past decade that has identified irisin as a potential therapeutic agent in the prevention or treatment of various metabolic-related and other diseases. This article delineates structural and biochemical aspects of irisin and provides an insight into the role of irisin in different pathological conditions.  相似文献   
67.
The effect of addition of 3-methyl-1-pentylimidazolium tetrafluoroborate ([C5mim][BF4]) on the micellization of a nonionic surfactant, Triton X-100 (TX-100), has been investigated. The techniques employed to study the aggregation behavior are fluoremetry, dynamic light scattering (DLS), and transmission electron microscopy (TEM) and the concentration range covered is 0–2?wt% [C5mim][BF4]. The probes, viz. pyrene and pyrene-1-carboxaldehyde (PyCHO), have been used for fluorescence analysis. According to the findings, the addition of pentyl-chained ionic liquid (IL) to aqueous TX-100 results in a dramatic increase in critical micelle concentration (cmc) decrease in micellar size, and aggregation number pointing toward an overall “unfavorable” aggregation process.  相似文献   
68.
Nanocomposites comprise functionalised multi-walled carbon nanotubes (0.00 wt%, 0.05 wt% and 0.07 wt%) and ferroelectric liquid crystals (FLCs) have been studied in the 5-μm- and 12-μm-thickness cells. Effect of anchoring energy and dopant concentration on the mesomorphic, electro-optic and dielectric behaviour of FLC has been explored. Fast switching time and increase in permittivity of non-doped FLCs and resulting nanocomposites as a function of increased cell thickness (from 5 to 12 μm) can be attributed to the change in the anchoring energy and direct current (DC) conductivity of the non-doped and doped systems. π–π stacking between carbon nanotubes and FLC layers give rise to the spontaneous polarisation of nanocomposites. Effect of cell thickness and anchoring energy on bistability are also discussed.  相似文献   
69.
Journal of Solid State Electrochemistry - Sodium-ion batteries are the commercially and environmentally viable next-generation candidates for automobiles. Structural and electrochemical aspects are...  相似文献   
70.
2‐Benzylidene‐1‐tetralones, obtained via Claisen condensation of 1‐tetralones with aromatic aldehydes, in one pot condensation with thiosemicarbazide/semicarbazide and α‐haloketones in the presence of trifluoroethanol and conc. HCl gives rise to a series of new substituted‐3,3a,4,5‐tetrahydro‐2H‐benzo[g]indazol‐2yl‐thiazoles. The condensation was also carried out in two steps, and the intermediates 3‐substituted‐3,3a,4,5‐tetrahydro‐2H‐benzo[g]indazole‐2‐carbothioamides/carboxamides, obtained in the first step by the reaction of 2‐bezylidene‐1‐tetralones with thiosemicarbazide/semicarbazide, on reaction with α‐haloketones gives rise to indazolyl–thiazoles. A detailed X‐ray diffractometry of intermediate (3aR)‐3‐phenyl‐3,3a,4,5‐tetrahydro‐2H‐benzo[g]indazole‐2‐carbothioamide were carried out to establish its crystal structure. Further, density functional theory studies on (3aR)‐3‐phenyl‐3,3a,4,5‐tetrahydro‐2H‐benzo[g]indazole‐2‐carbothioamide and its regioisomer were carried out. There is good correlation between the theoretical and experimental spectral data. The antibacterial and antifungal activities of the selected compounds were examined, and some are found to exhibit excellent activities.  相似文献   
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