The present study was carried out to investigate the effect of various combinations of different levels of NPK i.e. 0, 50, 75 and 100% recommended dose and potassium humate (K. humate) i.e. 0, 8, 12 and 16 kg ha-1 on yield parameters and economic performance of potato (Solanum tuberosum L.) cv. Cardinal under agro-climatic conditions of Multan (Pakistan). For the purpose, four field experiments, two for each of autumn and spring crops, were conducted during 2010-11 and 2011-12. NPK and K. humate application resulted in a significant improvement in yield attributes such as tuber number, tubers yield, tuber dry weight, biological yield and harvest index. The interaction between both fertilizers also caused significant effect on tuber fresh and dry weights and biological yield. There was a significant and economically positive response of the both autumn and spring crops to the applied NPK and K. humate levels. The highest tuber yield and harvest index were obtained at the application of 100% NPK recommended dose along with 16 kg K. humate ha-1. However, the highest benefit cost ratio (BCR) was recorded with 75% NPK recommended dose + 16 kg K. humate ha-1 in case of autumn crops and with 100% NPK recommended dose + K. humate 16 kg ha-1 in spring crops. The autumn crops were more beneficial than spring crop due to higher tuber yield and BCR value.
In this study, locally available adsorbent pineapple (Ananas cosmosus) peel has been tested by preparing activated carbon by KOH activation for its effectiveness in removing hexavalent chromium and divalent lead present in the water at low concentrations. Batch adsorption method was employed to investigate the efficiency of the adsorbent. Adsorption parameters like adsorbent dose, pH, contact time and temperature were obtained. Adsorption isotherms Freundlich and Langmuir, which states that heterogeneity of the adsorbent surface, were tested and the data obtained best fitted to Freundlich model. The adsorption kinetics followed pseudo-second-order kinetic model. Thermodynamic parameters for Pb (II) and Cr(VI) adsorption, enthalpy change, (-0.149 and -0.081kJ/mol), entropy change (0.183 and 0.012 kJ/mol), and Gibbs free energy change (-3.138 and -3.554 kJ/mol at 293 K, -3.191 and -3.615 kJ/mol at 298 K, -3.245 and -3.675 kJ/mol at 303 K), respectively have been calculated. The results showed that adsorption was feasible, spontaneous in nature, and exothermic.