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This study provides comprehensive details of evaporative cooling options for building air-conditioning (AC) in Multan (Pakistan). Standalone evaporative cooling and standalone vapor compression AC (VCAC) systems are commonly used in Pakistan. Therefore, seven AC system configurations comprising of direct evaporative cooling (DEC), indirect evaporative cooling (IEC), VCAC, and their possible combinations, are explored for the climatic conditions of Multan. The study aims to explore the optimum AC system configuration for the building AC from the viewpoints of cooling capacity, system performance, energy consumption, and CO2 emissions. A simulation model was designed in DesignBuilder and simulated using EnergyPlus in order to optimize the applicability of the proposed systems. The standalone VCAC and hybrid IEC-VCAC & IEC-DEC-VCAC system configurations could achieve the desired human thermal comfort. The standalone DEC resulted in a maximum COP of 4.5, whereas, it was 2.1 in case of the hybrid IEC-DEC-VCAC system. The hybrid IEC-DEC-VCAC system achieved maximum temperature gradient (21 °C) and relatively less CO2 emissions as compared to standalone VCAC. In addition, it provided maximum cooling capacity (184 kW for work input of 100 kW), which is 85% higher than the standalone DEC system. Furthermore, it achieved neutral to slightly cool human thermal comfort i.e., 0 to −1 predicted mean vote and 30% of predicted percentage dissatisfied. Thus, the study concludes the hybrid IEC-DEC-VCAC as an optimum configuration for building AC in Multan.

Wastewater containing heavy metals, such as nickel ions (Ni 2+), discharged from industry to water streams poses a serious threat because even at low concentrations, it does not naturally degrade and is toxic to human and aquatic life. This article reviews a novel technique for wastewater treatment using a Sayong ball clay (SBC) membrane to remove nickel from industrial wastewater. SBC powder was achieved through milling using a planetary ball mill (milling time; 10, 20 and 30 h), further labelled as SBC 10, SBC 20 and SBC 30, with a ball-to-powder of ratio 7:1 and rotation speed of 300 rpm. The physical characteristics of the apparent porosities, bulk density and shrinkage were investigated. XRD was used to study the phase, while FESEM was used to analyse the microstructure of the fired membrane. The FESEM microstructure indicates a decreased particle size (SB30). Filtration was conducted using a dead-end filtration system. The fabricated SBC 10, 20 and 30 membranes showed significant removal of nickel from industrial wastewater-88.87%, 82.96% and 85.13%, respectively. This study revealed that the SBC membrane is a promising membrane to remove nickel from industrial wastewater. The results also indicate the possibility of highlighting the introduced technique as a new technique for the treatment of industrial wastewater. As a new trend for waste management, pollution prevention could be applied in Malaysia as one of the advanced biotechnologies to solve various environmental problems.

We report the prevalence of extended-spectrum β-lactamases and carbapenemases in Escherichia coli isolated from retail chicken in Peshawar, Pakistan. One hundred E. coli isolates were recovered from retail chicken. Antibiotic susceptibility testing was carried out against ampicillin, chloramphenicol, kanamycin, nalidixic acid, cephalothin, gentamicin, sulfamethoxazole-trimethoprim, and streptomycin. Phenotypic detection of β-lactamase production was analyzed through double disc synergy test using the antibiotics amoxicillin-clavulanate, cefotaxime, ceftazidime, cefepime, and aztreonam. Fifty multidrug-resistant isolates were screened for detection of sul1, aadA, cmlA, int, bla, bla, bla, bla, bla, bla, and bla genes. Resistance to ampicillin, nalidixic acid, kanamycin, streptomycin, cephalothin, sulfamethoxazole-trimethoprim, gentamicin, cefotaxime, ceftazidime, aztreonam, cefepime, amoxicillin-clavulanate, and chloramphenicol was 92, 91, 84, 73, 70, 67, 53, 48, 40, 39, 37, 36, and 23% respectively. Prevalence of sul1, aadA, cmlA, int, bla, bla, bla, and bla was 78% ( n = 39), 76% ( n = 38), 20% ( n = 10), 90% ( n = 45), 74% ( n = 37), 94% ( n = 47), 22% ( n = 11), and 4% ( n = 2), respectively. bla, bla, and bla were not detected. The coexistence of multiple antibiotic resistance genes in multidrug-resistant strains of E. coli is alarming. Hence, robust surveillance strategies should be developed with a focus on controlling the spread of antibiotic resistance genes via the food chain.

Thermally driven adsorption-based atmospheric water harvesting (AWH) is becoming an emerging technology to provide potable water. In this regard, various adsorbent materials including solid (MOFs, silica-gels, and zeolites), liquid (CaCl2 and LiCl), and composite adsorbents are explored in the literature. This study reviews recent advancements in adsorbent materials based on their water production capacity at different conditions that is air temperature and relative humidity (RH). The MOF of type MIL-101(Cr) shows water production capacity of 3.10 L/m2/day at RH ranging from 10% to 40%. Similarly, Zr-MOF-808 possesses water production capacity of 8.60 L/m2/day at RH more than 50%. Among the studied silica-gels, mesoporous silica-gel shows highest water production capacity that is 1.30 L/m2/day at RH ranging from 10% to 40%. The zeolite yielded water production capacity of 0.94 L/m2/day at RH ranging from 10% to 40%. On the other hand, liquid adsorbents like CaCl2 + cloth, K-LiCl showed water production capacity of 3.02 L/m2/day, and 2.9 g/g/day, respectively at RH of about 70%. Composite adsorbent modified with binary salts and functionalized carbon nanotubes resulted water production capacity of 5.60 g/g at RH of about 35%. The study will be useful to identify the energy-efficient adsorbent for the development of sustainable AWH device.