2,408 research outputs found
Enhanced Removal Efficiency of Arsenic and Copper from Aqueous Solution Using Activated Acorus calamus Based Adsorbent
Water security, due to heavy metal pollution in water resources, has become a serious problem in modern urbanized society. Plants with a good source of cellulose, hemicellulose, pectin, lignin, etc., are the most promising adsorbents for the removal of heavy metals from water. In this work, for the first time, a low-cost local plant named Acorus calamus (AC; flag root or sweet flag) and citric acid modified AC root powder (CAMAC) were used as potential adsorbents. The samples were characterized by SEM, FT-IR, XRD, and the sorption properties were investigated by different parameters, such as solution pH, batch kinetic study, batch isotherm, effect of adsorbent dose, effect of initial concentration, and effect of contact time. The results of ACRP on removal efficiency of copper (II) and arsenic (III) in an aqueous solution showed an excellent adsorption behavior (~ 80 % adsorption efficiency). This study opens up an easy and economical method for the decontamination of harsh polluting metal ions from water.
This work is licensed under a Creative Commons Attribution 4.0 International License
Intangible-Related Profit Allocation within MNEs based on Key DEMPE Functions: Selected Issues and Interaction with Pillar One and Pillar Two of the Digital Debate
Thermal Instability in a Horizontal Layer of Walter’s (Model B\u27) Visco-Elastic Nanofluid- A More Realistic Approach
Thermal instability in a horizontal layer of Walter’s (Model B\u27) visco-elastic nanofluid is investigated for more realistic boundary conditions. The flux of volume fraction of nanoparticles is taken to be zero on the isothermal boundaries. The model used for nanofluid incorporates the effect of Brownian diffusion and thermophoresis. Perturbation method, normal mode technique and Galerkin method are used in the solution of the eigenvalue problem. Oscillatory convection has been ruled out for the problem under consideration. The influences of the Lewis number, modified diffusivity ratio and nanoparticle Rayleigh number on the stationary convection are shown both analytically and graphically
Kinesin Light Chains Are Essential for Axonal Transport in Drosophila
Kinesin is a heterotetramer composed of two 115-kD heavy chains and two 58-kD light chains. The microtubule motor activity of kinesin is performed by the heavy chains, but the functions of the light chains are poorly understood. Mutations were generated in the Drosophila gene Kinesin light chain (Klc), and the phenotypic consequences of loss of Klc function were analyzed at the behavioral and cellular levels. Loss of Klc function results in progressive lethargy, crawling defects, and paralysis followed by death at the end of the second larval instar. Klc mutant axons contain large aggregates of membranous organelles in segmental nerve axons. These aggregates, or organelle jams (Hurd, D.D., and W.M. Saxton. 1996. Genetics. 144: 1075-1085), contain synaptic vesicle precursors as well as organelles that may be transported by kinesin, kinesin-like protein 68D, and cytoplasmic dynein, thus providing evidence that the loss of Klc function blocks multiple pathways of axonal transport. The similarity of the Klc and Khc ((Saxton et al. Cell 64:1093-1102; Hurd, D.D., and W.M. Saxton. 1996. Genetics 144: 1075-1085) mutant phenotypes indicates that KLC is essential for kinesin function, perhaps by tethering KHC to intracellular cargos or by activating the kinesin motor
Intensification of oxidation capacity using chloroalkanes as additives in hydrodynamic and acoustic cavitation reactors
The effect of the presence and absence of the chloroalkanes, dichloromethane (CH2Cl2), chloroform (CHCl3) and carbon tetrachloride (CCl4) on the extent of oxidation of aqueous I- to I3- has been investigated in (a) a liquid whistle reactor (LWR) generating hydrodynamic cavitation and (b) an ultrasonic probe, which produces acoustic cavitation. The aim has been to examine the intensification achieved in the extent of oxidation due to the generation of additional free radicals/oxidants in the reactor as a result of the presence of chloroalkanes. It has been observed that the extent of increase in the oxidation reaction is strongly dependent on the applied pressure in the case of the LWR. Also, higher volumes of the chloroalkanes favour the intensification and the order of effectiveness is CCl4> CHCl3 > CH2Cl2. However, the results with the ultrasonic probe suggest that an optimum concentration of CH2Cl2 or CHCl3 exists beyond which there is little increase in the extent of observed intensification. For CCl4, however, no such optimum concentration was observed and the extent of increase in the rates of oxidation reaction rose with the amount of CCl4 added. Stage wise addition of the chloroalkanes was found to give marginally better results in the case of the ultrasonic probe as compared to bulk addition at the start of the run. Although CCl4 is the most effective, its toxicity and carcinogenicity may mean that CH2Cl2 and CHCl3 offer a safer viable alternative and the present work should be useful in establishing the amount of chloroalkanes required for obtaining a suitable degree of intensification
Stability Analysis of Double-diffusive Convection in a Couple Stress Nanofluid
Stability of double-diffusive convection in a horizontal layer of nanofluid is studied. The couple-stress fluid model is employed to describe the rheological behavior of the nanofluid. Stability of nanofluid has been influenced by the features of couple-stress fluid, suspended nanoparticles and examined under the consideration of momentum and thermal slip boundary conditions. By applying normal mode analysis method and linear stability theory, the dispersion relation describing the effect of various parameters is derived. We have assumed that the nanoparticle concentration flux is zero on the boundaries which neutralizes the possibility of oscillatory convection and only stationary convection occurs. The impact of the physical parameters, like the couple stress parameter, solutal-Rayleigh Number, thermo-nanofluid Lewis number, thermo-solutal Lewis number, Soret parameter and Dufour parameter have also been observed and compared with the published work. A very good agreement is found between the present paper and earlier published results
PHARMACEUTICAL STANDARDIZATION OF JATIPHALADYA VATI
Standardization is the process of developing and agreeing upon technical standards. A standard is a document that establishes uniform engineering or technical specifications, criteria, methods, processes or practices. Many drugs are described in Ayurvedic classical texts for the treatment of various disorders. Jatiphaladya Vati is one such Kharaliya Rasayana mentioned in Rasendra Saara Samgraha, indicated in Arshas (Haemorrhoids). Jatiphala (Myristica fragrans Houtt.), Lavanga (Syzygium aromaticum), Pippali (Piper longum), Saindhava lavana (Rock salt), Shunthi (Zingiber officinale Roxb), Dhattura beeja (Datura metel Linn.), Hingula (Cinnabar) and Tankana (Borax) are the main ingredients. Shodhana (Purification), Churna nirmana (Preparation of powder), Bhavana (Soaking with liquid and triturating till drying) and Mardana (Trituration) are the important steps involved in preparation of Jatiphaladya Vati. Shodhana of Hingula, Tankana and Dhattura beeja was carried out by classical method to remove the impurities. Churna of all above ingredients were prepared by subjecting it to grinding in Khalwa yantra and filtering through cloth. All ingredients were mixed properly to make homogenous mixture; later on it was triturated with Nimbu swarasa to obtain 250 mg tablets (brick red in colour) in tablet compression machine. The present study has been planned to standardize the method of preparation of an important Herbo-mineral formulation i.e. Jatiphaladya Vati
- …