Waste newspaper driven activated carbon to remove polycyclic aromatic hydrocarbon from wastewater.

In this study, a carbon-based adsorbent was developed from waste newspaper through pyrolysis at 800 °C to evaluate the removal efficiency of polycyclic aromatic hydrocarbons (Benzo[ghi]perylene (BghiP) and Indeno [1,2,3-cd] pyrene (IP)) from wastewater. The surface area of the developed adsorbent was estimated at 509.247m2g-1 which allowed the adsorption of the PAHs from wastewater. The maximum adsorption capacity was estimated at 138.436 µg g-1 and 228.705 µg g-1 for BghiP and IP, respectively and the highest removal efficiency was observed at pH 2. Around 91% removal efficiency was observed at pH 7 for both pollutants. Experimental adsorption data were fit for pseudo-second-order kinetics and Langmuir isotherm models, which demonstrate electrostatic interaction, monolayered deposition, hydrogen bonding, and π-π interaction between adsorbate and adsorbent which play a significant role in adsorption. The regeneration study described that the developed adsorbent could be able to intake 52.75% BghiP and 48.073% IP until the 8th and 6th cycles, respectively. The removal efficiency of the adsorbent in the real sample was also evaluated. This study will provide a method to convert waste material into adsorbent and will remove PAHs from wastewater as a function of pollutant mitigation and waste management.

Effect of fibre loading on mechanical properties of jute fibre bundle reinforced gypsum composites.

Gypsum plasterboards are widely used in interior decoration like false ceilings, wall partitioning etc. The main component of this plasterboard is gypsum, which is a mineral material. These boards contain poor mechanical strength with lower durability. The addition of natural fibres in these plasterboards can be useful to achieve better mechanical properties. Since Jute fibre is abundant in Bangladesh and its usability in reinforced composites is well established, for this reason, jute fibre was selected to do the research. The aim of this study was to evaluate the impact of jute fibre on the mechanical properties of the gypsum plasterboard. To make this board, Plaster of Paris and water were thoroughly mixed to make a suspension first. Different fibre loadings of 2, 4, 6, and 8% were incorporated into gypsum composites. Reinforcement of 6% fibre provided the highest tensile properties, but 8% fibre loading showed inferior tensile and flexural properties. Impact test results showed a gradually improving nature with fibre loading, and hardness values showed a decreasing trend in hardness with higher fibre loading. FTIR results and SEM images confirmed that no significant chemical bonding took place in the composites, instead, the composite depended mainly on the mechanical bonding among the reins crystals and between the fibre and gypsum matrix.

Incorporation of Ag-doped ZnO nanorod through Graphite hybridization: Effective approach for degradation of Ciprofloxacin.

To remove the Ciprofloxacin (CIP) from aqueous solution, ZnO-Ag-Gp nanocomposite exhibited efficient photocatalytic properties. The biopersistent CIP is pervasive in surface water and also hazardous to human and animal health. This study utilized the hydrothermal technique to prepare Ag-doped ZnO hybridizing Graphite (Gp) sheet (ZnO-Ag-Gp) to degrade pharmaceuticals pollutant CIP from an aqueous medium. The structural and chemical compositions of the photocatalysts were determined by XRD, FTIR and XPS analysis. FESEM and TEM images revealed the nanorod ZnO with round shape Ag distributed on a Gp surface. The reduced bandgap of the ZnO-Ag-Gp sample enhanced the photocatalytic property which was measured by using UV-vis Spectroscopy. Dose optimization study found that 1.2 g/L is optimum for single (ZnO) and binary (ZnO-Gp and ZnO-Ag), where 0.3 g/L ternary (ZnO-Ag-Gp) exhibited maximum degradation efficiency (98%) within 60 min for 5 mg/L CIP. Pseudo 1st order reaction kinetics rate was found highest for ZnO-Ag-Gp (0.05983 min-1) and it decreased to 0.03428 min-1 for annealed sample. Removal efficiency decreased to only 90.97% at 5th run and hydroxyl radicals played a vital role to degrade CIP from aqueous solution. UV/ZnO-Ag-Gp will be a promising technique to degrade wide-ranging pharmaceutical antibiotics from the aquatic medium.

Forced Convective Heat Transfer Coefficient Measurement of Low Concentration Nanorods ZnO-Ethylene Glycol Nanofluids in Laminar Flow.

This paper presents the experimental forced convective heat transfer coefficient (HTC) of nanorods (NRs) zinc oxide-ethylene glycol nanofluids (ZnO-EG NFs) in laminar flow. First, ZnO NRs were synthesized using a hydrothermal method that uses zinc acetate dihydrate [Zn(CH3COO)2·2H2O] as a precursor, sodium hydroxide as a reducing agent, and polyvinylpyrrolidone (PVP) as a surfactant. The hydrothermal reaction was performed at 170 °C for 6 h in a Teflon-lined stainless-steel tube autoclave. The sample's X-ray diffraction (XRD) pattern confirmed the formation of the hexagonal wurtzite phase of ZnO, and transmission electron microscopy (TEM) analysis revealed the NRs of the products with an average aspect ratio (length/diameter) of 2.25. Then, 0.1, 0.2, and 0.3 vol% of ZnO-EG NFs were prepared by adding the required ZnO NRs to 100 mL of EG. After that, time-lapse sedimentation observation, zeta potential (ζ), and ultraviolet-visible (UV-vis) spectroscopy was used to assess the stability of the NFs. Furthermore, the viscosity (µ) and density (ρ) of NFs were measured experimentally as a function of vol% from ambient temperature to 60 °C. Finally, the HTC of NFs was evaluated utilizing a vertical shell and tube heat transfer apparatus and a computer-based data recorder to quantify the forced convective HTC of NFs in laminar flow at Reynolds numbers (Re) of 400, 500, and 600. The obtained results indicate that adding only small amounts of ZnO NRs to EG can significantly increase the HTC, encouraging industrial and other heat management applications.

Isolation, characterization and in vitro antioxidant activity screening of pure compound from black pepper (Piper nigrum).

The present study's aims of isolation, characterization and in vitro antioxidant activity screening of pure compound from Black pepper (Piper nigrum) were investigated. Nowadays, scientific exploration of medicinal plants from natural sources has become the prime concern globally. All the crude drugs that have been isolated from natural plant origin (herbs, root, stem, bark, fruit and flower) have great significance in drug discovery as well as a lead compound to demonstrate great synergistic effect on pharmacology. For this research work, methanol was selected as a mother solvent, and the crude methanolic extract of black pepper was partitioned in between the solvent chloroform and di-ethyl-ether. A crystal fraction has been eradicated from the chloroform extract of black pepper (Piper nigrum). The crystal compound (C1) was isolated and purified by using thin layer chromatography (TLC) and recrystallization technique. The purified crystal compound (C1) isolated from black pepper possesses a strong in vitro antioxidant activity. The IC50 value of crystal compound (C1) was 4.1 µg/ml where the standard one had 3.2 µg/ml. Physical, phytochemical and chromatographical characterization of pure crystal compound (C1) has been explored, and from the analysis of all characteristics, it was found that, crystal compound (C1) might have resembling features of the standard Piperine of black pepper. The overall research work was really remarkable and introduced a convenient way of isolating pure compound from the natural source which will be a great referential resource in isolating crude drugs for future analysis.

A novel approach for pineapple leaf fiber processing as an ultimate fiber using existing machines.

This research aims to study the spinnability of pristine PALF and PALF blended cotton using the existing spinning machines. Apron draft ring spinning frame and flyer jute spinning frame were used to produce 100% PALF yarn and the yarns count were found 121 tex and 138 tex separately. Besides, 90:10 and 80:20 cotton-PALF blended 30 tex yarn spun in a cotton spinning system with different twist factors. With both yarns, two samples; 1/1 plain and 3/1 twill fabrics, were fabricated through equal density. For plain and twill fabric, PALF yarn of 121 tex and 138 tex were used in the warp way, respectively and PALF blended cotton yarn of 60 tex was used in the weft way. Through the study, physio-mechanical properties of the samples were explored and FTIR & XRD patterns were analyzed to perform the task for diversified use as an ultimate fiber in industrial and domestic purposes.

Antiparasitic, nematicidal and antifouling constituents from Juniperus berries.

A bioassay-guided fractionation of Juniperus procera berries yielded antiparasitic, nematicidal and antifouling constituents, including a wide range of known abietane, pimarane and labdane diterpenes. Among these, abieta-7,13-diene (1) demonstrated in vitro antimalarial activity against Plasmodium falciparum D6 and W2 strains (IC(50) = 1.9 and 2.0 microg/mL, respectively), while totarol (6), ferruginol (7) and 7beta-hydroxyabieta-8,13-diene-11,12-dione (8) inhibited Leishmania donovani promastigotes with IC(50) values of 3.5-4.6 microg/mL. In addition, totarol demonstrated nematicidal and antifouling activities against Caenorhabditis elegans and Artemia salina at a concentration of 80 microg/mL and 1 microg/mL, respectively. The resinous exudate of J. virginiana afforded known antibacterial E-communic acid (4) and 4-epi-abietic acid (5), while the volatile oil from its trunk wood revealed large quantities of cedrol (9). Using GC/MS, the two known abietanes totarol (6) and ferruginol (7) were identified from the berries of J. procera, J. excelsa and J. phoenicea.