Physicochemical Characterization of Starch from Unripe Lam Pulp as a Low-Cost Starch Source for Oilfield Applications

2019 ◽  
Author(s):  
C. N Adewumi ◽  
O Achugasim ◽  
R. E Ogali ◽  
O Akaranta
2021 ◽  
Vol 2021 ◽  
pp. 1-41
Author(s):  
H. E. Reynel-Ávila ◽  
K. I. Camacho-Aguilar ◽  
A. Bonilla-Petriciolet ◽  
D. I. Mendoza-Castillo ◽  
H. A. González-Ponce ◽  
...  

This review covers the preparation, characterization, and application of magnetic adsorbents obtained from carbon-based sources and their application in the adsorption of both inorganic and organic pollutants from water. Different preparation routes to obtain magnetic adsorbents from activated carbon, biochar, hydrochar, graphene, carbon dots, carbon nanotubes, and carbon nanocages, including the magnetic phase incorporated on the solid surface, are described and discussed. The performance of these adsorbents is analyzed for the removal of fluoride, arsenic, heavy metals, dyes, pesticides, pharmaceuticals, and other emerging and relevant water pollutants. Properties of these adsorbents and the corresponding adsorption mechanisms have been included in this review. Overall, this type of magnetic adsorbents offers an alternative for facing the operational problems associated to adsorption process in water treatment. However, some gaps have been identified in the proper physicochemical characterization of these adsorbents, the development of green and low-cost preparation methods for their industrial production and commercialization, the regeneration and final disposal of spent adsorbents, and their application in the multicomponent adsorption of water pollutants.


2019 ◽  
Vol 21 (1) ◽  
pp. 166 ◽  
Author(s):  
Małgorzata Zienkiewicz-Strzałka ◽  
Anna Deryło-Marczewska ◽  
Yury A. Skorik ◽  
Valentina A. Petrova ◽  
Adam Choma ◽  
...  

A simple, low-cost, and reproducible method for creating materials with even silver nanoparticles (AgNP) dispersion was established. Chitosan nanofibers with silica phase (CS/silica) were synthesized by an electrospinning technique to obtain highly porous 3D nanofiber scaffolds. Silver nanoparticles in the form of a well-dispersed metallic phase were synthesized in an external preparation step and embedded in the CS/silica nanofibers by deposition for obtaining chitosan nanofibers with silica phase decorated by silver nanoparticles (Ag/CS/silica). The antibacterial activity of investigated materials was tested using Gram-positive and Gram-negative bacteria. The results were compared with the properties of the nanocomposite without silver nanoparticles and a colloidal solution of AgNP. The minimum inhibitory concentration (MIC) of obtained AgNP against Staphylococcus aureus (S. aureus) ATCC25923 and Escherichia coli (E. coli) ATCC25922 was determined. The physicochemical characterization of Ag/CS/silica nanofibers using various analytical techniques, as well as the applicability of these techniques in the characterization of this type of nanocomposite, is presented. The resulting Ag/CS/silica nanocomposites (Ag/CS/silica nanofibers) were characterized by small angle X-ray scattering (SAXS), X-ray diffraction (XRD), and atomic force microscopy (AFM). The morphology of the AgNP in solution, both initial and extracted from composite, the properties of composites, the size, and crystallinity of the nanoparticles, and the characteristics of the chitosan fibers were determined by electron microscopy (SEM and TEM).


2020 ◽  
pp. 99-103
Author(s):  
A De Olivera ◽  
C Kreutz ◽  
R Martins

The pharmaceuticals as emerging contaminants have become one of the most controversial environmental issues at global scale. Over the years, the presence of antibiotics and anti-inflammatory drugs inside rivers, lakes, and even inside drinking water streams has increased. The wastewater treatment plants (WWTPs) lack the necessary technology to remove concentrations between the range ng/l-mg/l and therefore, the need to develop new methods able to remove contaminants in an effective, low cost and environmental friendly way arises. The present work is focused on studying the potential adsorption capacity of Moringa oleífera (MO) to remove Diclofenac (DCF) and Oxytetracycline (OTC) from wastewater. Through different experiences, it was possible to characterizes the main functional groups of MO and determine the principal responsible of the biosorption process.


2021 ◽  
Vol 66 ◽  
pp. 73-84
Author(s):  
Farzaneh Saeedi Landi ◽  
Babak Negahdari ◽  
Fariba Esmaeili ◽  
Sedigheh Kolivand ◽  
Amir Amani

Electrospray technique has received increasing attentions for intracellular gene delivery as well as production of nanoparticles. In this study, chitosan/pDNA nanoparticles with N/P ratio of 5 were prepared and transferred to HEK293T cells by electrospray technique. Physicochemical characterization of prepared nanoparticles, including size, zeta potential and entrapment efficiency was performed and attachment of pDNA to chitosan was confirmed by gel agarose electrophoresis. Moreover, transfection efficiency was investigated using flow cytometry. MTT assay was performed for cell viability studies. Nanoparticles were prepared at three pDNA concentrations of 10, 55 and 100 μg/ml in fixed N/P ratio. Size of nanoparticles was obtained as 110, 188 and 240 nm, using DLS. SEM showed size of 102.34 ± 10.66 nm for samples having 55 μg/ml pDNA. Zeta potential and entrapment efficiency were +25 mv and 85±4%m respectively. The effect of pDNA concentration, electrospray time and incubation time on transfection efficiency was investigated using Box-Behnken design. Percent of GFP-positive cells was 41.05 ± 3.04% which was taken as an indicator of transfection efficiency. Transfection efficiency of this method was then compared with that of calcium phosphate (31.1 ± 2.4%), showing improved efficiency. Considering the fact that electrospray is an easy, low cost, one-step process which makes low damage to cells and produces monodispersed nanoparticles, the method is introduced as a fascinating approach in gene transfection.


2019 ◽  
Vol 38 (2) ◽  
pp. 385 ◽  
Author(s):  
Marwa M. El-Naggar ◽  
Wael S. I. Abou-Elmagd ◽  
Ashraf Suloma ◽  
Hamza A. El-Shabaka ◽  
Magdy T. Khalil ◽  
...  

Author(s):  
Kumar P ◽  
S Kumar ◽  
A Kumar ◽  
M Chander

The purpose of this study was to prepare and characterize solid dispersions of the antibacterial agent Cefdinir with PEG 4000 and PVP K-30 with a view to improve its dissolution properties. Investigations of the properties of the dispersions were performed using release studies, X-ray powder diffraction (XRD) and Fourier transform infrared (FTIR). The results obtained showed that the rate of dissolution of Cefdinir was considerably improved when formulated in solid dispersions with PVP K-30 and PEG 4000 as compared with pure drug and physical mixtures. The results from XRD studies showed the transition of crystalline nature of drug to amorphous form, while FTIR studies demonstrated the absence of drug-carriers interaction.


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