Raun Duran (oxygenfir9)

In order to increase CO2/N2 selectivity of polyimide (PI) dense membranes, task-specific ionic liquid (TSIL), 1-aminoethyl-3-buthylimidazolium hexafluorophosphate ([NH2ebim][PF6]), has been grafted to polymer chains as large side groups by forming the structure of Schiff base for the first time. The modified membranes were characterized by Fourier transform infrared spectroscopy (FT-IR), elemental analysis, thermogravimetric analysis (TGA), X-ray diffraction (XRD), dynamic thermomechanical analysis (DMA), and stress-strain testing. The results showed that TSIL had been successfully linked to PI chains by forming "C=N." The modified membranes had more free volume, which was favorable to the improvement of CO2 permeability. The reduction of spin degree of freedom means the rigidity increment of polymer chains, which indicated that the selectivity of CO2/N2 can be enhanced. As a result, CO2 permeability of the modified membrane (TSIL-0.8 wt%) was increased from 5.28 to 10.2 Barrer, and CO2/N2 selectivity was increased from 21.9 to 92.8 at 30 °C and 0.1 MPa. Meanwhile, the effects of different feed pressures (0.1-0.6 MPa) and different operating temperatures (30-60 °C) on CO2/N2 transport properties were also investigated, and it was found that the separation performances of the modified membranes had already exceeded Robeson's upper bound.The economic complexity index, which indicates the level of knowledge and skills needed in the production of the exported goods, is a measure of economic development. Some researchers have investigated the validity of the environmental Kuznets curve (EKC) hypothesis by considering the effect of economic complexity on environmental pollution. This study, for the first time, examines the impact of economic complexity, globalization, and renewable and non-renewable energy consumption on both CO2 emissions and ecological footprint within the framework of the EKC hypothesis in the USA. To this end, the combined cointegration test and three different estimators are utilized for the period from 1980 to 2016. The main finding of the study indicates that the inverted U-shaped EKC relationship between economic complexity and environmental pollution holds for the USA. In addition to this finding, globalization and renewable energy consumption play a dominant role in reducing environmental pollution, while non-renewable energy consumption contributing factor to environmental pressure. Overall, the outcomes indicate that increasing economic complexity helps to minimize environmental degradation after a threshold, and the US government can provide a better environment by using renewable energy sources and globalization. Graphical abstract.The aquaponic system is an alternative strategy to treat aquaculture waste and achieve food independence. Bacteria play vital roles in the aquaponic system as they can transform ammonia or ammonium into nitrite and then into nitrate, which is more favorable for bacteria, fish, and plants. The objective of this study was to determine the effect of nitrifying bacteria (Nitrosomonas europaea Winogradsky and Nitrobacter winogradskyi Winslow) on the aquaponic system in terms of water quality, nutrient availability, and productivity of carp (Cyprinus carpio), lettuce (Lactuca sativa var. crispa), and vetiver grass (Chrysopogon zizanioides L.). The experiment consisted of four treatments aquaculture of carp as a control for fish (A), hydroponic of lettuce and vetiver grass without nutrient addition as a control for plants (B), aquaponic (carp, lettuce, vetiver grass) (C), and aquaponic with nitrifying bacteria addition (D). The results showed nitrifying bacteria addition had a significant effect on daily growth rate (DGR) and relative growth rate (RGR) of lettuce within a treatment; on the other hand, the nitrifying bacteria did not give a significant effect to RGR of vetiver grass. The growth rate, specific growth rate, and survival rate of the carp in aquaculture treatment (A)