Pretreatment of Palm Oil Mill Effluent (POME) Using Magnetic Chitosan

Chitosan is a natural organic polyelectrolyte of high molecular weight and charge density; obtained from deacetylation of chitin. This study explored the potential and effectiveness of applying chitosan-magnetite nanocomposite particles as a primary coagulant and flocculent, in comparison with chitosan for pre-treatment of palm oil mill effluent (POME). A series of batch coagulation processes with chitosan-magnetite nanocomposite particles and chitosan under different conditions, i.e. dosage and pH were conducted, in order to determine their optimum conditions. The performance was assessed in terms of turbidity, total suspended solids (TSS) and chemical oxygen demand (COD) reductions. Chitosan-magnetite particles showed better parameter reductions with much lower dosage consumption, compared to chitosan, even at the original pH of POME, i.e. 4.5. At pH 6, the optimum chitosan-magnetite dosage of 250 mg/L was able to reduce turbidity, TSS and COD levels by 98.8%, 97.6% and 62.5% respectively. At this pH, the coagulation of POME by chitosan-magnetite was brought by the combination of charge neutralization and polymer bridging mechanism. On the other hand, chitosan seems to require much higher dosage, i.e. 370 mg/L to achieve the best turbidity, TSS and COD reductions, which were 97.7%, 91.7% and 42.70%, respectively. The synergistic effect of cationic character of both the chitosan amino group and the magnetite ion in the pre-treatment process for POME brings about enhanced performance for effective agglomeration, adsorption and coagulation

Bio-nanotechnology application in wastewater treatment

The nanoparticles have received high interest in the field of medicine and water purification, however, the nanomaterials produced by chemical and physical methods are considered hazardous, expensive, and leave behind harmful substances to the environment. This chapter aimed to focus on green-synthesized nanoparticles and their medical applications. Moreover, the chapter highlighted the applicability of the metallic nanoparticles (MNPs) in the inactivation of microbial cells due to their high surface and small particle size. Modifying nanomaterials produced by green-methods is safe, inexpensive, and easy. Therefore, the control and modification of nanoparticles and their properties were also discussed

Biochemical Analysis on Blood and Crop Contents of Household Chickens Along With Their Production and Health Status in Bangladesh

This study aimed to assess the biochemical parameters of household chickens at crop and blood levels and measure the body weight. For this purpose, 350 Deshi (local) and 27 Fayoumi day old chicks were reared in 2 separate brooders within a house for 15 days. Body weight, serum total protein and calcium levels of these chicks were evaluated on day 0 and 15. After control house trial, birds were distributed among the selected households. Again, body weights and certain biochemical parameters were assessed from randomly selected birds at 60, 120 and 180 days of age. Fayoumi birds gained higher weight (P<0.001) than at control trial, whereas Deshi birds attained better weight (P<0.001) at household. Crop contents were dominated by carbohydrate. The level of crude proteins and calcium in crop contents increased along with age regardless of bird types. The average phosphorous in the crop contents was 0.3% (60 days), 2.6% (120) and 0.7% (180) regardless of bird types. Both serum total protein (P<0.05) and calcium (P<0.05) were significantly difference in between bird types at control house study. In conclusion, Deshi birds attained higher weight at household. The crude protein was below standard. Calcium and Phosphorous levels in the crop contents varied with ages, regardless of bird types

The enhanced YSO population in Serpens

The Serpens Molecular Cloud is one of the most active sites of ongoing star formation at a distance of about 300 pc, and hence is very well-suited for studies of young low-mass stars and sub-stellar objects. In this paper, for the Serpens star forming region, we find potential members of the Young Stellar Objects population from the Gaia DR3 data and study their kinematics and distribution. We compile a catalog of 656 YSOs from available catalogs ranging from X-ray to the infrared. We use this as a reference set and cross-match it to find 87 Gaia DR3 member stars to produce a control sample with revised parameters. We queried the DR3 catalog with these parameters and found 1196 stars. We then applied three different density-based machine learning algorithms (DBSCAN, OPTICS and HDBSCAN) to this sample and found potential YSOs. The three clustering algorithms identified a common set of 822 YSO members from Gaia DR3 in this region. We also classified these objects using 2MASS and WISE data to study their distribution and the progress of star formation in Serpens.Comment: Accepted in Journal of Astrophysics and Astronomy (JoAA

Using GMM in Open Cluster Membership: An Insight

The unprecedented precision of Gaia has led to a paradigm shift in membership determination of open clusters where a variety of machine learning (ML) models can be employed. In this paper, we apply the unsupervised Gaussian Mixture Model (GMM) to a sample of thirteen clusters with varying ages ($log \ t \approx$ 6.38-9.64) and distances (441-5183 pc) from Gaia DR3 data to determine membership. We use ASteca to determine parameters for the clusters from our revised membership data. We define a quantifiable metric Modified Silhouette Score (MSS) to evaluate its performance. We study the dependence of MSS on age, distance, extinction, galactic latitude and longitude, and other parameters to find the particular cases when GMM seems to be more efficient than other methods. We compared GMM for nine clusters with varying ages but we did not find any significant differences between GMM performance for younger and older clusters. But we found a moderate correlation between GMM performance and the cluster distance, where GMM works better for closer clusters. We find that GMM does not work very well for clusters at distances larger than 3~kpc.Comment: Accepted in Astronomy & Computin

Enhancement of Lipase Enzyme Activity in Non-Aqueous Media through a Rapid Three Phase Partitioning and Microwave Irradiation

Three phase partitioning is fast developing as a novel bio-separation strategy with a wide range of applications including enzyme stability and enhancement of its catalytic activity. pH tuning of enzyme is now well known for use in non-aqueous systems. Tuned enzyme was prepared using a rapid drying technique of microwave dehydration (time required around 15 minutes). Further enhancement was achieved by three phase partitioning (TPP) method. With optimal condition of ammonium sulphate and t-butanol, the protein appeared as an interfacial precipitate between upper t-butanol and lower aqueous phases. In this study we report the results on the lipase which has been subjected to pH tuning and TPP, which clearly indicate the remarkable increase in the initial rate of transesterification by 3.8 times. Microwave irradiation was found to increase the initial reaction rates by further 1.6 times, hence giving a combined increase in activity of about 5.4 times. Hence it is shown that microwave irradiation can be used in conjunction with other strategies (like pH tuning and TPP) for enhancing initial reaction rates

Biodiesel production from waste cooking sunflower oil and environmental impact analysis

Waste cooking oil offers great potential as a low cost biodiesel feedstock. Several parameters were tested for the optimumproduction of biodiesel and these included varying the alcohol:oil molar ratios, different catalyst concentrations,temperatures and stirring speed. For the optimum production of biodiesel, the molar ratio of alcohol to oil used was 6:1.The fatty acid methyl esters identified in the biodiesel were methyl palmitate, methyl linoleate, methyloleate and methylstearate. The viscosity of the produced biodiesel was within the range of international ASTM standards. Engine exhaustemission tests of biodiesel showed that the carbon monoxide and unburned hydrocarbon emissions were lower than thatof petrodiesel. The nitrogenous oxides emission and specific fuel consumption were higher than that of conventionaldiesel fuel. It can be concluded that biodiesel produced from waste sunflower oil can be considered as a great potentialsource of commercial biodiesel

Effects of root dehydration on biomechanical properties of woody roots of <i>Ulex europaeus</i>

Aims: Effects of root water status on root tensile strength and Young’s modulus were studied in relation to root reinforcement of slopes. Methods: Biomechanical properties of woody roots, Ulex europaeus, were tested during progressive dehydration and after thirty-day moisture equilibration in soil with contrasting water contents. Root diameter, water content and water loss were recorded and root water potential versus water content relation was investigated. Tensile stresses induced by root contraction upon dehydration were measured. Results: Root tensile strength and Young’s modulus increased abruptly when root water content dropped below 0.5 g g −1. The strength increase was due to root radial and axial contraction induced by root water potential drop. Diameter decrease and strength gain were the largest for thin roots because of the relatively larger evaporative surface per volume of thin roots. Largely negative water potentials in dry soil induced root drying, affecting root biomechanical properties. Conclusion: Root water status is a factor that can cause (inappropriately) high strength values and the large variability reported in literature for thin roots. Therefore, all root diameter classes should have consistent moisture for fair comparison. Testing fully hydrated roots should be the routine protocol, given that slope instability occurs after heavy rainfall. </p

Microwave Enhanced Synthesis of Chitosan- graft

Polymers have been molecularly imprinted for the purpose of binding specifically to α-tocotrienol (vitamin E). A molecularly imprinted polymer (MIP) material was prepared using α-tocotrienol as the imprinted molecule, acrylamide as functional monomer and macroporous chitosan beads as functional matrix. Chitosan-graft-polyacrylamide was synthesized without any radical initiator or catalyst using microwave (MW) irradiation. The representative microwave synthesized graft copolymer was characterized by fourier transform-infrared spectroscopy, taking chitosan as a reference. Microwave irradiation was exploited for polyacrylamide grafting on the cross-linked chitosan beads to produce MIP, where both time as well as chemicals can be saved. It can be assumed that the chitosan coated polyacrylamide MIP will have better pH stability and enhanced adsorption capacity. The maximum adsorption capacity was observed to be 3.95 mg/g of MIP, which gave removal efficiency of 93%. After 4 h, the change of adsorption capacities for α-tocotrienol did not show notable effects. The Langmuir and Freundlich adsorption models were also applied to describe the equilibrium isotherms

Missed opportunities for family planning counselling among postpartum women in eleven counties in Kenya

Background: Mothers may access medical facilities for their babies and miss opportunities to access family planning (FP) services. This study was undertaken to describe missed opportunities for FP among women within the extended (0–11months) postpartum period from counties participating in Performance Monitoring and Accountability 2020 (PMA2020) surveys. Design and setting: This study analysed cross-sectional household survey data from 11 counties in Kenya between 2014 and 2018. PMA2020 uses questions extracted from the Demographic and Health survey (DHS) and DHS defnitions were used. Multivariable logistic regression was used for inferential statistics with p-value of \u3c0.05 considered to be signifcant. Participants: Women aged 15-49 years from the households visited. Primary outcome measure: Missed opportunity for family planning/contraceptives (FP/C) counselling. Results: Of the 34,832 women aged 15-49 years interviewed, 10.9% (3803) and 10.8% (3746) were in the period 0–11months and 12–23months postpartum respectively, of whom, 38.8 and 39.6% respectively had their previous pregnancy unintended. Overall, 50.4% of women 0-23months postpartum had missed opportunities for FP/C counselling. Among women who had contact with health care at the facility, 39.2% of women 0-11months and 44.7% of women 12-23months had missed opportunities for FP/C counselling. Less than half of the women 0-11months postpartum (46.5%) and 64.5% of women 12 – 23months postpartum were using highly efcacious methods. About 27 and 18% of the women 0-11months and 12 – 23months postpartum respectively had unmet need for FP/C. Multivariable analysis showed that being low parity and being from the low wealth quintile signifcantly increased the odds of missed opportunities for FP/C counselling among women in the extended postpartum period, p\u3c0.05. Conclusions: A large proportion of women have missed opportunities for FP/C counselling within 2 years postpartum. Programs should address these missed opportunities