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Pakistan experiences extreme flood events almost every year during the monsoon season. Recently, flood events have become more disastrous as their frequency and magnitude have increased due to climate change. This situation is further worsened due to the limited capacity of existing water reservoirs and their ability to absorb and mitigate peak floods. Thus, the simulation of stream flows using projected data from climate models is essential to assess flood events and proper water resource management in the country. This study investigates the future floods (in near future and far future periods) using the integrated flood analysis system (IFAS) model under the RCP2.6, RCP4.5, and RCP8.5 climate change scenarios. Downscaled and bias corrected climatic data of six general circulation models and their ensemble were used in this study. The IFAS model simulated the stream flow efficiently (R2 = 0.86–0.93 and Nash–Sutcliffe efficiency = 0.72–0.92) in the Jhelum River basin (JRB), Kabul River basin (KRB), and upper Indus River basin (UIRB) during the calibration and validation periods. The simulation results of the model showed significant impact of projected climate change on stream flows that will cause the mean monthly stream flow in the JRB to be lower, while that of the KRB and UIRB to be higher than that of the historical period. The highest flow months are expected to shift from May–June (Jhelum basin) and June–July (Kabul basin) to April–May with no changes in the UIRB. Higher frequencies of low to medium floods are projected in the KRB and UIRB, while the JRB expects fewer flood events. Based on the results from the IFAS model, it is concluded that stream flow in the study area will increase with several flood events. [ABSTRACT FROM AUTHOR]

Mechanized harvesting is one of the components of agricultural mechanization used to overcome grain losses and enhance the production compared to the conventional harvesting. Power tiller operated reapers are quite effective for harvesting practices in small fields and especially in mountainous regions where the crops are grown on terraces. Compared to the tractor mount reaper and combine harvester, it saves fuel and cuts the maximum straw to produce the fodder of almost 4000 kg ha-1 after the threshing operation. Thus, in case of wheat crop, it helps to save a significant energy of 1,524,000 kcal ha-1 avoiding the environmental pollution by infield burn of the straw. However, un-optimized use of power tiller operated reaper may result in high maintenance cost, low efficiency and distress among the small land holding farmers. The main objective of this study was to quantify the optimum cutting knife dynamics by optimizing the performance parameters of power tiller operated reaper like cutting speed, operating speed, cutting index, field capacity and fuel consumption. A combination of forward speed at 2.82 km h-1 and cutting speed at 3.42 km h-1 with cutting index of 1.21 was found to be most effective for a minimum grain harvesting loss of 101.33±1.0 kg ha-1 at a fuel consumption of 6.27±0.030 L ha-1. A higher field efficiency of 71% was also recorded at cutting index of 1.21 for the same combination of forward and cutting speeds. Locus of cutter bar knife for the optimum combination of forward and cutting speeds helped to examine the operation of crank and cutter bar, prolonging the life of cutting mechanism. Thus, optimized performance of power tiller operated reaper will help to attain higher field efficiency at low fuel consumption and low maintenance. [ABSTRACT FROM AUTHOR]

Experiments were conducted to investigate the effect of experimental factors (types of promotor and noble metals, H2injection, and suspension pH) on catalytic nitrate reduction by bimetallic catalysts supported by nanoscale zero-valent iron (NZVI). NZVI without H2injection showed 71% of nitrate reduction in 1 h. Cu/NZVI showed the almost complete nitrate reduction (96%) in 1 h, while 67% of nitrate was reduced by Ni/NZVI. The presence of noble metals (Pd and Pt) on Cu/NZVI without H2injection resulted in the decrease of removal efficiency to 89% and 84%, respectively, due probably to the electron loss of NZVI for formation of metallic Pd and Pt. H2injection into Cu-Pd/NZVI suspension significantly improved both catalytic nitrate reduction (>97% in 30 min) and N2selectivity (18%), indicating that adsorbed H on active Pd sites played an important role for the enhanced nitrate reduction and N2selectivity. The rapid passivation of NZVI surface resulted in a dramatic decrease in nitrate reduction (79–28%) with an increase in N2selectivity (8–66%) as the suspension pH increased from 8 to 10. [ABSTRACT FROM PUBLISHER]

In this study, we investigated catalyticnitrate removal usingnanoscale zerovalent iron (NZVI) supported Cu–Pd bimetalliccatalyst (Cu–Pd/NZVI) in a continuous reactor system. Controlexperiments showed that Cu, Pd, and a proper supply of H2are essential for relatively sustainable nitrate (30 mg/L NO3–-N) reduction in continuous mode. Whenwe optimized operational parameters to enhance removal efficiencyand N2selectivity, we finally achieved complete nitrateremoval with 48% N2selectivity at 9 h. During a longevitytest (200 h reaction), excellent removal was observed (>91% in24h) with 42–60% N2selectivity. However, removalgradually decreased to 13% in 200 h with increasing nitrite production.X-ray diffraction, transmission electron microscopy, and X-ray photoelectronspectroscopy analysis revealed that both the support (NZVI) and theCu(0) oxidized after continuous denitrification. This indicated thatloss of NZVI reductive capacity and the oxidation of Cu(0) to Cu(I)and Cu(II) deactivated nitrate removal during the continuous nitratereduction by Cu–Pd/NZVI. [ABSTRACT FROM AUTHOR]

The ability of encapsulated Burkholderia cepacia G4 (ATCC 53617) for trichloroethylene (TCE) degradation (1.5, 5, 10, and 20 mg/L) in the presence of toluene (10 and 60 mg/L) as enhancement substrate was evaluated experimentally. Burkholderia cepacia G4 cultures were encapsulated in cylindrical pellets (4 mm in diameter and 4 mm in height (preferred)) using polyethylene glycol (PEG). Higher transformation capacities were observed for the encapsulated cultures for both toluene concentrations. The highest transformation capacities measured for the encapsulated cultures and suspended cultures were 46.98 and 5.94 μg TCE/mg biomass, respectively. The Monod equation was used to simulate the degradation rates of toluene and Haldane's equation was employed to describe the degradation kinetics of TCE. The first-order reaction rate constant ( k/ Ks) for toluene degradation in the encapsulated cultures was 2.3-fold higher than the value of the suspended cultures, whereas the kc/ Ksc value for TCE was 4.3-fold higher compared to the suspended cultures. The higher kinetic values of the encapsulated cultures indicate that the degradation efficiency and capability of B. cepacia G4 was enhanced through PEG encapsulation. Moreover, the higher inhibition constant value for the encapsulated cultures compared with the suspended cultures demonstrated that PEG-encapsulated B. cepacia G4 can tolerate and degrade much higher TCE concentrations. [ABSTRACT FROM AUTHOR]

The effect of biomass density, effect of different ratios of trichloroethylene (TCE) and toluene on biomass, and strategies to cope with problems using acclimated Burkholderia cepacia G4 were investigated. Complete degradation of TCE was achieved when B. cepacia G4 was exposed to 0.5 mg/L TCE and 10 mg/L toluene after starvation of 100 h. Overall results of this study show that degradation rates of toluene decreased as TCE concentration increased. On the contrary, degradation rates of TCE increased up to 10 mg/L TCE and then decreased. Transformation capacity of B. cepacia G4 increased as toluene concentration increased but transformation yield decreased showing that excessive substrate supply may not help to improve specific performance parameters. Results of these experiments bear that instead of simultaneous injection of TCE and substrate, the supply of substrate in pulses can increase the efficiency of B. cepacia G4 or similar bacterial strains. [ABSTRACT FROM AUTHOR]

Textile wastewater, heavily contaminated with organic dyes, is generating severe problems to environment and human health. The implementation of gC 3 N 4 with biochar (gC 3 N 4 -BC) for the treatment of textile wastewater is less effective due to the limited adsorption capacity and slower degradation kinetics. To tackle these problems, peroxydisulfate (PDS) is integrated with gC 3 N 4 -BC photocatalyst to enhance the process efficiency and kinetics. The synthesized gC 3 N 4 -BC-5 composite shows higher separation of charge carriers, light absorbance, and lower energy bandgap (2.62 eV). The results of photocatalytic degradation and rate constant are enhanced up to 99.9 % and 0.041 min -1 using gC 3 N 4 -BC-5 with PDS as compared to without PDS (96.8 % and 0.028 min -1 , respectively). The radicals (SO 4 -• ,O 2 -• , and OH • ) are responsible to improve the degradation process efficiency and kinetics. The reusability of optimized sample indicates that gC 3 N 4 -BC-5 is stable and effective up to five cycles. The gC 3 N 4 -BC-5 composite attains highest adsorption (70.9 %) when compared to BC (62.3 %) and pure gC 3 N 4 (27.1 %). The well-fitted models of adsorption (Pseudo-Second-Order and Freundlich) confirm the favorable, chemical, and multilayered adsorption process. The coupling of gC 3 N 4 -BC-5 with PDS is effective, efficient, and stable process to enhance the kinetics and degradation of textile wastewater., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)