Search results for " isotherm"

Removal of Pesticide Oxadixyl from an Aqueous Solution

2007

ABSTRACT The mycelium of Phomopsis helianthi (Ascomycete) was hydrolyzed with boiling NaOH to give an insoluble fraction composed of chitosan and glucans. The biomass obtained was tested as an agent for the removal of pesticides from an aqueous solution. Oxadixyl, which has a solubility in water of 3400 mg L−1, has been chosen as a hydrophilic organic contaminant model. The new, cheap material was demonstrated to recover up to 6 mg of oxadixyl per gram of adsorbent. The experimental data show an excellent correlation with the Langmuir isotherm model.

Monolayer Properties of Hydrophobic .alpha.-Helical Peptides Having Various End Groups at the Air/Water Interface

1994

Controlling the wetting properties of the Asakura-Oosawa model and applications to spherical confinement.

2012

We demonstrate for the Asakura-Oosawa model and an extension of this model that uses continuous rather than hard potentials, how wetting properties at walls can be easily controlled. By increasing the interaction range of the repulsive wall potential acting on the colloids (while keeping the polymer-wall interactions constant) polymers begin to substitute colloids at walls and the system can be driven from complete wetting of colloids via partial wetting to complete wetting of polymers. As an application, we discuss the morphology and wetting behavior of colloid-polymer mixtures in spherical confinement. We apply the recently developed 'ensemble switch method' where the Hamiltonian is exten…

Investigation of Adsorption behaviour of Acetone Vapour towards a Surface Plasmon Resonance Sensing Layer using Adsorption Isotherm Models

2021

Abstract Surface plasmon resonance (SPR) sensors are widely explored due their ultra-sensitivity to even a minute alteration of refractive index. Knowledge of adsorption processes could be exploited to explain the performance and interaction mechanism of an SPR sensor. Here in, we report the fitting of the experimental SPR sensing data during the detection of low concentrations of acetone vapour (0.5-5 ppm) using the linearized and non-linearized format of the Langmuir and the Freundlich isotherm models. The sensing layer is made from a ternary composite material of doped polyaniline, reduced graphene oxide and chitosan. The objective is to find the best model, understand the interaction me…

Efficiency of biochar for reducing mobility of inorganic contaminants

2013

Anthropogenic activities have produced numerous sites with extensive contamination close to residential areas. Several physicochemical and biological remediation methods exist for remediation of metal contaminated soils and lands, such as soil washing, soil flushing, phytoremediation, and electrokinetics. Biochar (biologically derived charcoal) is produced by pyrolysis of biomasses under low oxygen conditions, and it can be applied for recycling organic waste in soils. The main objectives of the present study were to determine the possible use of biochar from forest ersidues (Populus nigra) in order to achieve a stabilization of inorganic contaminants by adsorption processes. Adsorption of …

Protein Adsorption Hysteresis and Transient States of Fibrinogen and BMP-2 as Model Mechanisms for Proteome-Binding to Implants

2020

Abstract Protein adsorption studies returned to the focus of medical therapeutics, when it was found that up to 2500 non-plasma proteins adsorbed to hip implants during arthroplastic surgery, challenging peri-implant healing models. Questions have re-emerged as to the implications of uncontrolled protein unfolding after adsorption. In past studies on the cooperativity of protein binding we discovered protein adsorption hysteresis, a thermodynamically irreversible process. The present precursory study comprises real-time kinetic (TIRF-Rheometry) and equilibrium (125I-tracer ) studies on the hysteretic binding of fibrinogen and rhBMP-2 to titanium and glass surfaces via transient states. Ther…

Removal of Fe(III) from synthetic wastewater into raw and modified clay: Experiments and models fitting

2017

Water pollution by heavy metal ions has become a serious environmental issue especially due to their toxicity and tendency to bioaccumulation. Natural smectite clay was treated using sulfuric acid ...

In-Field LAMP Detection of Flavescence Dorée Phytoplasma in Crude Extracts of the Scaphoideus titanus Vector

2022

One of the most destructive diseases affecting grapevine in Europe is caused by Flavescence Dorée phytoplasma (FDp), which belongs to the 16Sr-V group and is a European Union quarantine pathogen. Although many molecular techniques such as loop-mediated isothermal amplification (LAMP) are widely used for the rapid detection of FDp in infected grapevine plants, there is no developed isothermal amplification assay for FDp detection in the insect vectors that are fundamental for the spread of the disease. For this reason, a simple in-field real-time LAMP protocol was optimized and developed for the specific detection of FDp in the insect vector Scaphoideus titanus. The LAMP assay was optimized …

Phosphorous removal from human urine using lateritic soil

2023

Phosphorous (P) in human urine is among the macronutrients in municipal wastewater that has exacerbated eutrophication of water bodies. Adsorption of P from wastewater using cost effective, environmentally friendly, and efficient adsorbents is considered as an attractive method that can both mitigate the eutrophication problem and augment the already strained P reserves. In the present study the adsorption capacity and structural properties of lateritic soil (LS), the adsorbent for removal of P from human urine, was investigated using XRF, SEM, TGA and FTIR techniques. Batch adsorption experiments were conducted to determine various adsorption parameters such as the sorption rates, the conc…

Ocena właściwości sorpcyjnych Hottonia palustris L.

2016

Zbadano w warunkach laboratoryjnych kinetykę i równowagę procesu sorpcji wybranych metali ciężkich: Cu i Zn w roślinie wodnej - okrężnicy bagiennej (Hottonia palustris L.). Wykazano, że stan równowagi w układzie roztwór soli metalu - okrężnica bagienna zostaje osiągnięty po około 60 minutach. W warunkach prowadzenia eksperymentu około 36% jonów miedzi i około 49% jonów cynku sorbowanych jest z roztworów początkowych w pierwszych 10 minutach. Do opisu równowag wykorzystano model izotermy Langmuira. Stwierdzono, że Hottonia palustris L. sorbuje jony metali ciężkich proporcjonalnie do ich zawartości w roztworze, w którym została zanurzona. Na podstawie przeprowadzonych badań można przypuszczać…