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The novel flower-like Co9S8/reduced graphene oxide (rGO) microsphere nanocomposites were synthesized using wet chemical method in combination with a spray drying technique. The structures and morphologies of as-synthesized Co9S8/rGO nanocomposites were characterized by X-ray diffractometer (XRD), scanning electron microscopy (SEM) and transmission electron microscope (TEM). The results reveal that Co9S8 is homogeneously dispersed on the surface of rGO microspheres. The significantly enhanced photocatalytic activity of Co9S8/rGO nanocomposites in comparison with a pure Co9S8 was investigated by the degradation of methylene blue (MB) using ultraviolet (UV) spectroscopy. The photodegradation ratios of MB using flower-like Co9S8/rGO nanocomposites with a Co9S8 mass ratio of 67.3, 35.3 and 55.6 wt% are about 86.7, 92.0, and 98.7%, respectively, after irradiation for 80 min. By comparing the nanocomposites and pure flower-like Co9S8, the pure Co9S8 showed less photocatalytic activity upon the degradation of MB than the nanocomposites. It can be attributed to the improved electron–hole pair separation and enhanced adsorption due to the presence of rGO microspheres. [ABSTRACT FROM AUTHOR]

Some new pyrimidine derivatives have been synthesised by electrochemical oxidation of catechol (1a) in the existence of 2-mercapto-6-(trifluoromethyl) pyrimidine-4-ol (3) as a nucleophile in aqueous solution using Cyclic Voltammetric and Controlled Potential Coulometry. The catechol has been oxidised to o-quinone through electrochemical method and participative in Michael addition reaction, leading to the development of some new pyrimidine derivatives. The products were achieved in good yield with high pureness. The mechanism of the reaction has been conformed from the Cyclic Voltammetric data and Controlled Potential Coulometry. After purification, the compounds were characterised using modern techniques. The synthesised materials were screened for antimicrobial actions using Gram positive and Gram negative strain of bacteria. These new synthesised pyrimidine derivatives showed very good antimicrobial activity. [ABSTRACT FROM AUTHOR]

History shows that Pakistan and India have been vying for power in Afghanistan and they have been locked in a zero-sum struggle there since the inception of both the countries in 1947. Pakistan's losses in Afghanistan are considered India's victory and vice versa. The animosity between the two adversaries has manifested itself in a competition on the soil of Afghanistan for having a political clout, reminiscent of the competition and rivalry between the Tsarist Russia and then its successor, the Communist Russia, and the British Empire in the 19th and 20th centuries, respectively, and generally known as the "Great Game." The antagonism between Pakistan and India has been so strong and deep that both the countries lose no opportunity to checkmate each other on the Afghan soil. This paper is aimed at looking into the factors of Indo-Pak rivalry in Afghanistan. It will also shed light on Indo-Afghan relations in historical perspective and India's geo-political and geo-strategic interests in Afghanistan. Besides, the paper will also address the questions that what are the interests of Pakistan and India in Afghanistan and what are the implications of Indo-Pak rivalry in Afghanistan for the region and world at large. [ABSTRACT FROM AUTHOR]

A highly efficient, quick and environmentally benign protocol has been adopted to synthesize AuNPs using the plant extract of Sueda fruciotosa . UV–vis spectroscopy, XRD, HRTEM, SEM and FTIR were used to characterize the prepared AuNPs. Different concentrations of plant extract were used to optimize the size, morphology and distribution of AuNPs. AuNPs were of small size and spheroid in shape at lower concentration. AuNPs showed a surface plasmon resonance at 443 nm. According to HRTEM the average size of AuNPs was 6–8 nm. The AuNPs were appraised for their photo degradation activity on methylene blue (MB) as an experimental substrate. Photo-catalytic activity of AuNPs was found to be dependent on the concentration of catalyst, irradiation time, size and aggregation of AuNPs. Furthermore, AuNPs exhibited an excellent electro-catalytic activity. The sensitivity of modified AuNPs was also studied for phenolic Azo dyes (PAD) which showed its good degradation activity. These gold nanoparticles found to be significantly applicable in the field of electrochemistry, sensors, catalysis, nano-devices, treatment of waste water and conversion of toxic agents into less toxic compound. [ABSTRACT FROM AUTHOR]