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Development of inexpensive adsorbents from industrial wastes for the treatment of wastewaters is an important area in environmental sciences. Blast furnace slag, dust and sludge from steel plants, and carbon slurry from fertilizer plants after their treatment have been utilized as inexpensive adsorbents for the removal of phenols, which are an important class of pollutants as they are highly toxic. The characterization of the four adsorbents prepared has shown that the carbonaceous adsorbent prepared from carbon slurry possesses high porosity and maximum surface area (380 m2/g) as compared to the other three adsorbents (4−28 m2/g). The adsorption of four phenols (phenol, 2-chlorophenol, 4-chlorophenol, and 2,4-dichlorophenol) on these adsorbents is parallel to their porosity and surface area order. The uptake of the phenols on carbonaceous adsorbent is substantial and found to be 17.2, 50.3, 57.4, and 132.5 mg/g for phenol, 2-chlorophenol, 4-chlorophenol, and 2,4-dichlorophenol, respectively. The detailed adsorption studies on carbonaceous adsorbent have indicated that the adsorption process follows the Langmuir isotherm, is first order, and is pore diffusion controlled. As adsorption of phenols on prepared carbonaceous adsorbent is significant, its performance has been evaluated with respect to standard activated charcoal. The results indicate that the phenols removal efficiency of carbonaceous adsorbent is about 45% to that of a standard activated charcoal sample. Thus, the carbonaceous adsorbent can be used for the removal of phenols as a low-cost alternative (∼0.1 U.S.$/kg) to activated charcoal.

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We tune the coordination environment of macrocyclic ligands to design two novel fluorescence sensors for Mn(2+). The BODIPY-based Mn(2+) sensor M1 affords an excellent, 52 fold, fluorescence 'turn-on' response despite the paramagnetic nature of Mn(2+). The lipophilic probe is cell-permeable and confocal imaging demonstrates that the sensor distinctly detects Mn(2+) within live cells.

Switched capacitors (SCs)-based modules are being increasingly used for multilevel DC to AC power conversion, especially for low input voltage applications. Many of these topologies operate in two stages involving H-bridge switches, which endure high-voltage stress. The SC 9-level module (SC9LM) presented here operates in a single stage with one DC source and two capacitors. In addition, the peak inverse voltage of all power switches is confined to the voltage of the input DC source. The proposed 9-level module ensures a reduced number of power switches. In addition, with appropriate utilisation of states, two of the eleven switches in the module operate at fundamental switching frequency, thereby minimising the switching losses. A single SC9LM achieves a voltage gain of two. The proposed module is validated through circuit analysis followed by simulation and experimental results.

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A series of thiophene derivatives 1a-d & 2a-c were synthesized by condensation of 5-nitro-2-thiophene carboxaldehyde with mono and diamines respectively. Various imidazole derivatives 3a-c were obtained by condensing 4-(2-ethylamino)-1H-imidazole with 4-acetylpyridine, 2-acetylpyridine and 4-acetylbenzonitrile respectively. Pyridine derivatives 4a-e were synthesized by condensing 2-hydrazino-pyridine with various carbonyl compounds; 5a-c by condensing 2, 6-pyridine dicarbonyl dichloride with various aryl sulfonylhydrazides; 6, 7 by condensing 2, 6-dialdehyde pyridine with 2-hydrazinopyridine and anthranilonitrile respectively and compound 8 by condensing 2, 5-thiophene dialdehyde with hydrazinopyridine. All the compounds were characterized by IR, (1)HNMR, Mass spectra and elemental analysis. Compounds 1a-d; 2a-c; 3a-c; 4a-e; 5a-c, 6, 7 and 8 were screened for anti-inflammatory and analgesic activities. Compounds 1b and 2c exhibited good anti-inflammatory (26.5% and 33.4% at 50mg/kg p.o. respectively) and 3a, 3c good analgesic (100% and 75% at 100 mg/kg p.o. respectively) activities.