scholarly journals Adsorption Studies on Magnetic Nanoparticles Functionalized with Silver to Remove Nitrates from Waters

Water ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 1757
Author(s):  
Yesica Vicente-Martínez ◽  
Manuel Caravaca ◽  
Antonio Soto-Meca ◽  
Miguel Ángel Martín-Pereira ◽  
María del Carmen García-Onsurbe
Keyword(s):  
Magnetic Nanoparticles ◽  
Nitrate Content ◽  
Adsorption Efficiency ◽  
Experimental Conditions ◽  
Dependent Behavior ◽  
Before And After ◽  
Naoh Solution ◽  
High Concentrations ◽  
Interference Studies

This paper presents a novel procedure for the treatment of contaminated water with high concentrations of nitrates, which are considered as one of the main causes of the eutrophication phenomena. For this purpose, magnetic nanoparticles functionalized with silver (Fe3O4@AgNPs) were synthesized and used as an adsorbent of nitrates. Experimental conditions, including the pH, adsorbent and adsorbate dose, temperature and contact time, were analyzed to obtain the highest adsorption efficiency for different concentration of nitrates in water. A maximum removal efficiency of 100% was reached for 2, 5, 10 and 50 mg/L of nitrate at pH = 5, room temperature, and 50, 100, 250 and 500 µL of Fe3O4@AgNPs, respectively. The characterization of the adsorbent, before and after adsorption, was performed by energy dispersive X-ray spectroscopy, scanning electron microscopy, Brunauer-Emmett-Teller analysis and Fourier-transform infrared spectroscopy. Nitrates can be desorbed, and the adsorbent can be reused using 500 µL of NaOH solution 0.01 M, remaining unchanged for the first three cycles, and exhibiting 90% adsorption efficiency after three regenerations. A deep study on equilibrium isotherms reveals a pH-dependent behavior, characterized by Langmuir and Freundlich models at pH = 5 and pH = 1, respectively. Thermodynamic studies were consistent with physicochemical adsorption for all experiments but showed a change from endothermic to exothermic behavior as the temperature increases. Interference studies of other ions commonly present in water were carried out, enabling this procedure as very selective for nitrate ions. In addition, the method was applied to real samples of seawater, showing its ability to eliminate the total nitrate content in eutrophized waters.

Preparation and Characterization of Monodispersed Magnetic Nanoparticles with Carboxylic Groups via Polymerization Induced by a Double-Bond Ended Surfactant with Acrylic Acid

2013 ◽  
Vol 815 ◽  
pp. 112-115
Author(s):  
Jing Li ◽  
Guo Lun Zhong ◽  
Wen Kai Chen ◽  
Yong Hong Wang ◽  
Hong Lei Mao ◽  
...  
Keyword(s):  
Magnetic Nanoparticles ◽  
Double Bond ◽  
Acrylic Acid ◽  
Carboxyl Groups ◽  
Experimental Conditions ◽  
Carboxylic Groups ◽  
20 Nm ◽  
Carboxyl Functionalization ◽  
Undecenoic Acid

A new method for synthesizing magnetically responsive Fe3O4@UA@AA nanoparticles have been reported in this paper. The superparamagnetic Fe3O4@UA nanoparticles were prepared via carboxyl-functionalization of 10-undecenoic acid and Fe3O4@UA@AA made by a polymerization of 10-undecenoic acid on the surface of nanoparticles with acrylic acid. Thus the magnetic nanoparticles were functionalized with carboxylic groups. The compositions of as-prepared nanoparticles were characterized by FTIR, TGA, TEM, VSM and conductivity titration. Under optimized experimental conditions, Fe3O4@UA@AA nanoparticles with diameter of about 20 nm and 0.437mmol/g of carboxyl groups and 65 emu/g of saturation magnetization were prepared successfully.

scholarly journals Isolation and Characterization of Bacillus cereus Phage vB_BceP-DLc1 Reveals the Largest Member of the Φ29-Like Phages

2020 ◽  
Vol 8 (11) ◽  
pp. 1750
Author(s):  
Chun Li ◽  
Xiaoming Yuan ◽  
Na Li ◽  
Juan Wang ◽  
Shubo Yu ◽  
...  
Keyword(s):  
Bacillus Cereus ◽  
Dna Packaging ◽  
Model Organisms ◽  
Experimental Conditions ◽  
Isolation And Characterization ◽  
Bacillus Phage ◽  
Pharmaceutical Industries ◽  
High Concentrations ◽  
Ph Range

Bacillus phage φ29 and its relatives have been considered as one of the most important model organisms for DNA replication, transcription, morphogenesis, DNA packaging studies, and nanotechnology applications. Here, we isolated and characterized a new member of the φ29-like phage, named Bacillus cereus phage vB_BceP-DLc1. This phage, with a unique inserted gene cluster, has the largest genome among known φ29-like phages. DLc1 can use the surface carbohydrate structures of the host cell as receptors and only infects the most related B. cereus strains, showing high host-specificity. The adsorption rate constant and life cycle of DLc1 under experimental conditions were also determined. Not only stable under temperatures below 55 °C and pH range from 5 to 11, the new phage also showed tolerance to high concentrations of NaCl, 75% ethanol, chloroform, and mechanical vortex, which is preferable for practical use in the food and pharmaceutical industries.

scholarly journals PENURUNAN KADAR BESI (II) PADA AIR BERSIH MENGGUNAKAN AMPAS DAUN TEH DIAKTIVASI

2019 ◽  
Vol 17 (2) ◽  
Author(s):  
Laili Purwaningsih ◽  
Rachmaniyah . ◽  
Pratiwi Hermiyanti
Keyword(s):  
Contact Time ◽  
Polluted Water ◽  
Adsorption Efficiency ◽  
Tea Leaves ◽  
Anova Test ◽  
Iron Solution ◽  
Before And After ◽  
High Concentrations ◽  
One Way Anova ◽  
Spent Tea Leaves

The production of dried tea leaves and tea consumption in Indonesia has increased from year to year. This condition was directly proportional to the spent tea leaves produced. Spent tea leaves contained 37% cellulose which can adsorb heavy metals in polluted water. Iron (II) metal was often found in high concentrations in ground water, so a treatment process was needed. This study aimed to analyze the removal of iron (II) in water by using activated spent tea leaves.The type of this research was true experiment with a pretest-posttest controlled group design. Spent tea leaves with size 80 mesh was activated with 0.1 N HCl for 36 hours. The method was carried out with a batch system in an artificial iron solution the initial concentration was 9.85 mg / L, with mass of adsorbent was 10 grams, pH = 7, stirring speed 100 rpm, contact time 15 minutes, 25 minutes, and 35 minutes. Measurement of iron levels was carried out before and after treatment using the SSA method. FTIR test carried out before and after activated spent tea leaves were used adsorption. Data analysis was carried out descriptively and analytically (One-way Anova Test and LSD Test).The results showed that activated spent tea leaves can remove iron (II) levels in water. The result of One-way Anova test and LSD test, the higgest removal of iron (II) occurred at 35 minutes contact time with adsorption efficiency was 90.36%. FTIR test results showed that activated spent tea leaves in this study contained functional groups were O-H, C-H, C=O, C=C, and C-N.This study concluded that activated spent tea leaves can remove iron (II) in water. The higgest removal of iron (II) occurred at 35 minutes contact time. Further research is needed to achieve 100% adsorption efficiency and find an effort to reduce turbidity in sample water after treatment.

Influence of plutonyl ion on electrochemical characterization of zirconium in plutonium nitrate solutions

2020 ◽  
Vol 108 (9) ◽  
pp. 701-706
Author(s):  
Masaumi Nakahara ◽  
Yuichi Sano ◽  
Kazunori Nomura
Keyword(s):  
Open Circuit Potential ◽  
Nitrate Solution ◽  
Open Circuit ◽  
Electrochemical Characterization ◽  
Experimental Conditions ◽  
Breakdown Potential ◽  
Before And After ◽  
Reprocessing Plant ◽  
Nitrate Solutions

AbstractWith the aim of evaluating the corrosion behavior of a Pu evaporator made from Zr in the Rokkasho Reprocessing Plant (RRP), the electrochemical characterization of Zr was investigated in Pu nitrate solutions. Before and after experiments, spectra of Pu nitrate solutions were recorded, and Pu4+ was oxidized to PuO22+ by heating these solutions. The ratio of PuO22+ in 3 mol dm−3 HNO3 was higher than that in 7 mol dm−3 HNO3 in our experiments. The maximum open circuit potential of Zr in the Pu nitrate solution was approximately 1 V in the Pu nitrate solution containing 7 mol dm−3 HNO3. However, there were no significant changes at high PuO22+ concentrations, and this value remained below the passivity breakdown potential under our experimental conditions. In this study, Zr showed high corrosion resistance, even though many PuO22+ ions existed in the Pu nitrate solution containing 7 mol dm−3 HNO3.

scholarly journals Characterization of magnetic nanoparticles using programmed quadrupole magnetic field-flow fractionation

2010 ◽  
Vol 368 (1927) ◽  
pp. 4419-4437 ◽  
Author(s):  
P. Stephen Williams ◽  
Francesca Carpino ◽  
Maciej Zborowski
Keyword(s):  
Magnetic Field ◽  
Magnetic Material ◽  
Magnetic Nanoparticles ◽  
Specific Binding ◽  
Dipole Moments ◽  
Field Flow Fractionation ◽  
Experimental Conditions ◽  
Flow Fractionation ◽  
Quadrupole Magnetic Field

Quadrupole magnetic field-flow fractionation is a relatively new technique for the separation and characterization of magnetic nanoparticles. Magnetic nanoparticles are often of composite nature having a magnetic component, which may be a very finely divided material, and a polymeric or other material coating that incorporates this magnetic material and stabilizes the particles in suspension. There may be other components such as antibodies on the surface for specific binding to biological cells, or chemotherapeutic drugs for magnetic drug delivery. Magnetic field-flow fractionation (MgFFF) has the potential for determining the distribution of the magnetic material among the particles in a given sample. MgFFF differs from most other forms of field-flow fractionation in that the magnetic field that brings about particle separation induces magnetic dipole moments in the nanoparticles, and these potentially can interact with one another and perturb the separation. This aspect is examined in the present work. Samples of magnetic nanoparticles were analysed under different experimental conditions to determine the sensitivity of the method to variation of conditions. The results are shown to be consistent and insensitive to conditions, although magnetite content appeared to be somewhat higher than expected.

scholarly journals PENURUNAN KADAR BESI (II) PADA AIR BERSIH MENGGUNAKAN AMPAS DAUN TEH DIAKTIVASI

2019 ◽  
Vol 17 (2) ◽  
Author(s):  
Laili Purwaningsih ◽  
Rachmaniyah . ◽  
Pratiwi Hermiyanti
Keyword(s):  
Contact Time ◽  
Polluted Water ◽  
Adsorption Efficiency ◽  
Tea Leaves ◽  
Anova Test ◽  
Iron Solution ◽  
Before And After ◽  
High Concentrations ◽  
One Way Anova ◽  
Spent Tea Leaves

The production of dried tea leaves and tea consumption in Indonesia has increased from year to year. This condition was directly proportional to the spent tea leaves produced. Spent tea leaves contained 37% cellulose which can adsorb heavy metals in polluted water. Iron (II) metal was often found in high concentrations in ground water, so a treatment process was needed. This study aimed to analyze the removal of iron (II) in water by using activated spent tea leaves.The type of this research was true experiment with a pretest-posttest controlled group design. Spent tea leaves with size 80 mesh was activated with 0.1 N HCl for 36 hours. The method was carried out with a batch system in an artificial iron solution the initial concentration was 9.85 mg / L, with mass of adsorbent was 10 grams, pH = 7, stirring speed 100 rpm, contact time 15 minutes, 25 minutes, and 35 minutes. Measurement of iron levels was carried out before and after treatment using the SSA method. FTIR test carried out before and after activated spent tea leaves were used adsorption. Data analysis was carried out descriptively and analytically (One-way Anova Test and LSD Test).The results showed that activated spent tea leaves can remove iron (II) levels in water. The result of One-way Anova test and LSD test, the higgest removal of iron (II) occurred at 35 minutes contact time with adsorption efficiency was 90.36%. FTIR test results showed that activated spent tea leaves in this study contained functional groups were O-H, C-H, C=O, C=C, and C-N.This study concluded that activated spent tea leaves can remove iron (II) in water. The higgest removal of iron (II) occurred at 35 minutes contact time. Further research is needed to achieve 100% adsorption efficiency and find an effort to reduce turbidity in sample water after treatment. Keywords: Clean Water, Iron (II), Spent tea leaves

An Electron Microscope Study of Interdiffusion and Compound Formation in Ta-Au Thin Films

1973 ◽  
Vol 31 ◽  
pp. 32-33 ◽  
Author(s):  
T. C. Tisone ◽  
S. Lau
Keyword(s):  
Electron Microscope ◽  
Electron Microscope Study ◽  
Thermally Grown Oxide ◽  
Ion Milling ◽  
Compound Formation ◽  
Technology Application ◽  
Transmission Electron ◽  
Before And After ◽  
Au Thin Films

In a study of the properties of a Ta-Au metallization system for thin film technology application, the interdiffusion between Ta(bcc)-Au, βTa-Au and Ta2M-Au films was studied. Considered here is a discussion of the use of the transmission electron microscope(TEM) in the identification of phases formed and characterization of the film microstructures before and after annealing.The films were deposited by sputtering onto silicon wafers with 5000 Å of thermally grown oxide. The film thicknesses were 2000 Å of Ta and 2000 Å of Au. Samples for TEM observation were prepared by ultrasonically cutting 3mm disks from the wafers. The disks were first chemically etched from the silicon side using a HNO3 :HF(19:5) solution followed by ion milling to perforation of the Au side.

New Technologies for Decontamination of Radioactive Substances Scattered by Nuclear Accident / Nowe Technologie Dekontaminacji Radioaktywnych Substancji Rozproszonych Przez Awarie Nuklearna

2013 ◽  
Vol 58 (1) ◽  
pp. 283-290 ◽  
Author(s):  
Y. Nishizaki ◽  
H. Miyamae ◽  
S. Ichikawa ◽  
K. Izumiya ◽  
T. Takano ◽  
...  
Keyword(s):  
Radioactive Waste ◽  
New Technologies ◽  
Ferric Hydroxide ◽  
Nuclear Accident ◽  
Radioactive Cesium ◽  
Cesium Ions ◽  
Naoh Solution ◽  
High Concentrations ◽  
Water Rinsing

Our effort for decontamination of radioactive cesium scattered widely by nuclear accident in March 2011 in Fukushima, Japan has been described. Radioactive cesium scattered widely in Japan has been accumulating in arc or plasma molten-solidified ash in waste incinerating facilities up to 90,000 Bq/kg of the radioactive waste. Water rinsing of the ash resulted in dissolution of cesium ions together with high concentrations of potassium and sodium ions. Although potassium inhibits the adsorption of cesium on zeolite, we succeeded to precipitate cesium by in-situ formation of ferric ferrocyanide and iron rust in the radioactive filtrate after rinsing of the radioactive ash with water. Because the regulation of no preservation of any kind of cyanide substances, cesium was separated from the precipitate consisting of cesium-captured ferric ferrocyanide and ferric hydroxide in diluted NaOH solution and subsequent filtration gave rise to the potassium-free radioactive filtrate. Cesium was captured by zeolite from the potassium-free radioactive filtrate. The amount of this final radioactive waste of zeolite was significantly lower than that of the arc-molten-solidified ash.

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