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Energy storage materials, particularly chalcogenides, are fascinating electrode materials for supercapacitors (SCs) because of their high capacitance, remarkable electrical conductivity, and multiple oxidation states contributed by numerous metal cations. Herein, a novel nanocomposite based on zinc sulfide and copper diselenide, denoted as (ZnS–CuSe 2), was prepared via a sonochemical-assisted method. The structural analysis revealed the cubic structure for pure ZnS, orthorhombic for CuSe 2, and co-existing cubic and orthorhombic phases for ZnS–CuSe 2 nanocomposites with high purity and crystallinity. The ZnS–CuSe 2 nanocomposite offered exceptional electrochemical performance with redox peaks from the CV analysis, and coupled with plateaus in the charge/discharge profile, confirming the faradaic energy storage properties with functional reversibility. Similarly, a high conductive feature of the ZnS–CuSe 2 composite was revealed by impedance study, with a minor charge transfer resistance than their bulk materials. A hybrid asymmetric supercapacitor (HASCs) composed of ZnS–CuSe 2 //AC was constructed, which manifested an enlarged voltage window up to 1.7 V with capacitance of 95 F g−1 and a maximum specific energy of 38 Wh kg−1. Also, high power delivery was attained at 3927 Wkg-1 when specific energy goes down to 12 Wh kg− at 5 A g−1. Interestingly, only 81.8% retention was left beneath when cycled to 8000 cycles, specifying decent stability of the ZnS–CuSe 2 //AC HASCs. [ABSTRACT FROM AUTHOR]

Abstract: This article investigates the rapid expansion of private schooling in the Northern Areas of Pakistan during the period 1993–2003. Our observations are mainly based on a survey of about 40% of the total number of private schools in the Northern Areas in which we attested trends that are characteristic of many private schools elsewhere, both nationally and internationally. For instance, most of the parents are by no means wealthy, most think that private schools provide better quality than government schools, English-medium instruction is a key requirement, and all have pragmatic expectations of the benefits for their children both from private schooling and from English-medium education. [Copyright &y& Elsevier]