Pakistan is experiencing increasing CO2 emissions in contrast with other regions of the world. The country is also facing the problems of low economic growth, energy poverty, and environmental pollution. The objective of the study is to analyze economic growth of Pakistan and obtain some alternate sources of production for sustainable environment. Time series data of Pakistan from 1985 to 2018 is used. In order to estimate direct and substitution effect among energy and non-energy factors on economic growth, translog functional form is used. selleck chemicals llc The presence of multicollinearity among explanatory variables approves to employ ridge regression. Capital per worker has the highest elasticity (0.1531) among all variables followed by consumption of oil (0.0571), natural gas (0.0333), technology (0.0329), and hydroelectricity (0.02). Average output elasticity for oil, natural gas, hydroelectricity, capital per worker, and technology are 0.4474, 0.3127, 0.433, 1.0037, and 0.2309, respectively. Technical progress of variables is ranked as capital per worker, oil consumption, natural gas consumption, hydroelectricity, and technology. Relatively lower but efficient substitution between oil and natural gas provides opportunity to save huge foreign exchange on import of oil. Investment on capital per worker in transport, power, fertilizer, and industrial sectors can reduce the demand of oil and natural gas which would eventually lower carbon dioxide emissions in the country. Increasing 10% investment on capital/worker would mitigate 208.283 million tons of carbon dioxide. Energy inputs are substitutes; therefore, mega hydropower projects and small renewable projects may be launched to cope with energy poverty and environmentally sustainable challenges.The novel magnetic biochar (MBC), derived from co-pyrolysis of sewage sludge and biomass loading nanosized iron oxide particles, was used as an environmentally friendly adsorbent. The loading of magnetic particles was in favor of increasing the adsorption capacity and separation from aqueous system for biochar (BC). The physical/chemical characteristics of MBC were revealed by elemental analysis, VSM, SEM-EDS, XRD, FTIR, zeta potential, and batch adsorption-desorption experiments. The nanosized γ-Fe2O3 particles grown on the surface of biochar showed ferromagnetic property. For the remediation of Cu(II) contamination, MBC-5 showed remarkable adsorption capacity of 67.68 mg/g, and presented a wide pH range of 3.0-6.0. The Langmuir isothermal and pseudo-second-order model could describe adsorption process well. The adsorption mechanism of Cu(II) involved physical adsorption, ion exchange, and electrostatic surface complexation on the surface of MBCs. In the desorption experiments, MBC-5 holds the adsorption efficiency of 81.09% after fifth recycle still, which illustrated a remarkable performance of cyclic utilization by the solid waste of sewage sludge and biomass.A simple and effective tandem process of photo-electrocatalytic oxidation (PECO)-MoS2 adsorption was developed for the synchronous removal of triazole fungicides (TFs) and toxicological transformation products (TPs). In order to accurately identify trace TPs and evaluate degradation pathway during water treatment, a sensitive analytical method was developed on the basis of the stir bar sorptive extraction (SBSE) pretreatment tandem LC-MS/MS technique. Firstly, the typical TFs (PRO, TET, and DIN, C0 = 1.0 mg/L) in actual water samples were treated under the optimal process (bias voltage 1.8 V, pH 4, irradiation intensity 50 mW/cm2, 0.05 g MoS2/100 mL, 350 rpm, adsorption of 5 min). The result indicated that the residues of PRO, TET, and DIN in secondary effluent were 0.0973, 0.0617, and 0.0012 mg/L, respectively, with the removal rates of 90.3%, 93.8%, and 99.9%, respectively, undergoing 30-min photo-electrocatalysis and 5-min adsorption. The alkaline medium was favorable for the adsorption of MoS2 to TFs. The assessment results of potential cancer risk indicated that the residues of TFs in secondary effluent were safe for drinking water consumption. Besides, the major TPs were identified via the SBSE-HRLC-MS/MS technique, and one possible transformation pathway of TFs was proposed. TFs mainly underwent dehydrochlorination, cyclization, hydroxylation, etc. to produce a series of nitrogenous heterocyclic compounds that possess higher polarity than parents, hinting that TPs might pose potential aquatic toxicity. However, TPs can be removed synchronously by this tandem technique. The current study can provide a theoretical basis for the harmless treatment of TFs in the water environment.Studies have shown that mixed electron donors (MEDs) can enhance the CO2-fixing efficiency of non-photosynthetic microbial communities (NPMCs), even up to the level of fixation observed when H2 is used as an electron donor. However, this promotion effect is not stable because its mechanism remains unclear. To elucidate the mechanisms involved, allowing further regulation and optimization of the MED system for improving the CO2-fixing efficiency of NPMCs consistently, cbb gene transcription level and efficiency, extracellular free organic carbon (EFOC) content as well as microbial structure of NPMCs under MED and other electron donor systems were investigated. MEDs synergistically promoted CO2 fixation efficiency of NPMCs, even producing levels seen when H2 was used as the electron donor. Subsequent experiments revealed that the cbb gene abundance and transcription level in the MED system were high compared with those in other single-electron donor systems; the concentration of EFOC per unit cell was relatively lower than that in any other electron donor system; and the system developed a large number of dominant heterotrophic bacteria such as Enterobacteriaceae and Vibrionaceae. Data analysis revealed a high negative correlation between EFOC concentration per unit cell and cbb gene abundance as well as gene transcription level. These results implied that MEDs can promote a complex microbial community structure enriched with high-efficiency heterotrophic bacteria, which can effectively reduce excessive EFOC generated by NPMCs in the CO2 fixation process, promoting overall cbb gene abundance and transcription level within the NPMC and thus enhancing CO2 fixation.