Highly efficient catalytic degradation of low-density polyethylene using a novel tungstophosphoric acid/kaolin clay composite catalyst

In order to take advantage of Bronsted acidity of tungstophosphoric acid(TPA) and Lewis acidity of kaolin, TPA loaded kaolin catalysts with varying percentages of TPA (10-50wt%) have been prepared by wet impregnation method. Fourier Transform Infra-Red Spectrometer, X-ray diffractometer, Brunauer-Emmett-Teller surface area analyzer, and Scanning Electron Microscope characterizations were performed to confirm the successful loading of TPA onKaolin. Catalytic cracking of low-density polyethylene (LDPE), by employing our TPA loaded Kaolin as the catalyst, produced a higher percentage of fuel oil (liquid and gaseous hydrocarbons) with negligible amount of semisolid wax (1.0 wt.%), significantly lower compared to the thermal cracking which produced ~22wt.% solid black residue. Moreover, GCMS analysis of oil showed that thermal cracking produces mainly higher hydrocarbons(C22) as compared to the catalytic cracking where larger fraction oflowerhydrocarbons were obtained. We purpose that the higher performance of our catalysts was due to the presence of both Bronsted and Lewis acid sites, which increase their catalytic efficiency and degraded the LDPE at the relatively lower temperatures. Our results suggest that prepared materials were effectivecatalysts with low cost and easily scalable production method; suitable for large-scale highperformance catalytic cracking of LDPE based materials

EFFECT OF HUDIARA DRAIN ON THE QUALITY OF GROUNDWATER IN THE HOUSING SCHEMES OF LAHORE

A study was carried out to assess the effect of Hudiara Drain on groundwater quality in its vicinity, particularly some well planned residential neighborhoods such as Khayaban-e-Amin and Valencia in the city of Lahore (Qadeer, 2011). A total of eleven sampling points were selected. Three samples were collected from Hudiara Drain and eight samples were drawn from deep and shallow groundwater wells. Eight physical, chemical and biological parameters including pH, turbidity, total dissolved solids, total hardness, chloride, total iron, lead and total coliforms were examined and compared with the desired values mentioned in National Standards for Drinking Water Quality (NSDWQ) and World Health Organization (WHO) guidelines. The test results indicated that physical quality of all groundwater sources was satisfactory. Chemical quality of all groundwater sources was satisfactory for total dissolved solids (TDS), total hardness, and chlorides, however for total iron and lead the water quality was not meeting NSDWQ and WHO guidelines. Bacteriological contamination was also detected in almost all groundwater samples. The presence of higher concentrations of lead in groundwater certainly indicates that there is an external effect on groundwater. It is recommended that release of industrial wastewater in Hudiara Drain should be controlled and strictly monitored. In addition, proper disinfection should be practiced at the tube wells to ensure safe drinking water at the consumers end

Spatial distribution and water quality index of Lahore Canal, Pakistan

The Lahore Canal (LC) in Lahore city of Pakistan, with the discharge of 402 cusecs, runs along the city's centre. With rapid urbanization and population growth, the LC water is deteriorating. This study determined the water quality index and spatial distribution of pollutants. Three months of sampling from six separate locations were performed. Water quality parameters were analysed. The results indicated that pH, solids, turbidity, hardness, alkalinity, and chlorides were within guidelines, but DO BOD and nitrogen were beyond guidelines. Moderate BOD values (2.24–8.06 mg/L) and low DO values (0.13–3.56 mg/L) indicated a low oxygen environment. Heavy metal concentration was as follows: Fe > Pb > Cr > Cu. The Pearson correlation coefficient indicated ± poor to moderate (0.3–0.7) correlation. The ANOVA result supported the alternative hypothesis, i.e., the pollutants originated from the same source. Principal component analysis and cluster analysis showed three primary sources for the different pollutants based on loading of variance and Euclidean distance, respectively. The WQI of LC at all locations was above 300, indicating that LC water is not suitable for any usage. The spatial distribution of parameters indicated the effects of urbanization and commercialization (small household industries) at Location-4. The poor water quality of LC needs immediate government attention. HIGHLIGHTS The Lahore Canal (LC) showed an abundance of organic matter as untreated wastewater is discharged continuously in it.; The source and correlation study indicated various urban and domestic sources as a point of origin.; The water quality index of LC was above 300 indicating the LC water is not suitable for any activity.; The spatial distribution of parameters indicated the effects of urbanization and commercialization.

BEGSS! : pruning candidate selection for ConvNets

Deep learning has been used to get human-level performance on classification on some of the renowned problems like speech and object recognition. It is very difficult to port deep learning algorithms to resource-limited devices because of their computational cost. However, many ideas have been proposed by the researchers to reduce the computational cost and in this work, we addressed the same problem. We propose one of the promising techniques i.e., Pruning. Pruning starts with learning a large-sized network and then removing the least adversarial parameters. Since in feature map pruning, all the outgoing and incoming kernels are removed, which affects the parameters. Therefore, achieving a high pruning ratio is difficult. To achieve a high pruning ratio, we need to select the candidate for pruning intelligently. Therefore, we propose BEGSS! the pruning candidate selection based on Best of random, Entropy, Gray threshold, Sparsity, and Signal strength. We first computed the statistics of each feature map and select the least adversarial based on these statistics for pruning. The experimental results show that increasing pruning ratio results in degradation of network performance. On Cifar-10 dataset, introducing 70% pruning in the network resulted in 50% performance degradation but on the other hand, the inference time is reduced by 60% of actual inference time. To compensate for the performance degradation, we retrained the pruned network. After retraining the network, we found that the accuracy is improved even for a high pruning ratio. The proposed techniques performed better than existing absolute weight sum voting technique

Fe-POM/ attapulgite composite materials: efficient catalysts for plastic pyrolysis

This article describes the catalytic cracking of low-density polyethylene over attapulgite clay and iron substituted tungstophosphate/attapulgite clay (Fe-POM/attapulgite) composite materials to evaluate their suitability and performance for recycling of plastic waste into liquid fuel. The prepared catalysts enhanced the yield of liquid fuel (hydrocarbons) produced in cracking process. A maximum yield of 82% liquid oil fraction with a negligible amount of coke was obtained for 50% Fe-POM/attapulgite composite. Whereas, only 68% liquid oil fractions with a large amount of solid black residue was produced in case of non-catalytic pyrolysis. Moreover, Fe-POM/attapulgite clay composites showed higher selectivity towards lower hydrocarbons (C5–C12) with aliphatic hydrocarbons as major fractions. These synthesised composite catalysts significantly lowered the pyrolysis temperature from 375°C to 310°C. Hence, recovery of valuable fuel oil from polyethylene using these synthesised catalysts suggested their applicability for energy production from plastic waste at industrial level as well as for effective environment pollution control