Fabrication and Radiation Dose Properties of Well-dispersed Calcium Borate Nanoparticles

2019 ◽  
Vol 9 (2) ◽  
pp. 198-209
Author(s):  
Maryam E. Haghiri ◽  
Nayereh Soltani ◽  
Elias Saion ◽  
Azra Izanloo ◽  
Ghazaleh Bahmanrokh ◽  
...  
Keyword(s):  
Polymer Concentration ◽  
Chemical Properties ◽  
Frequency Factor ◽  
Heating Process ◽  
Calcium Borate ◽  
Heating Treatment ◽  
Mean Size ◽  
Co Precipitation ◽  
Average Size ◽  
Physical And Chemical

Background:Development of novel materials represents a new and fast evolving application of research in physics and medicine. The area of nanomaterial research has presented interesting physical and chemical properties that cannot be obtained from their macroscopic counterparts.Objective:This study has attempted to attain well-dispersed nanoparticles by variation of polymer concentration.Methods:In order to obtain the calcium borate nanoparticles, polyvinyl pyrrolidone has been used as a capping agent and the preparation method was performed via simple co-precipitation technique followed by heating treatment. In absence of polymer, the heating process causes un-controlled growth of particles with more flocculation and the nanoplate-shaped particles with mean size of 16.0 ×30.0 nm was formed. The introduction of polymer concentration of 1 wt% was conducted to the formation of spherical shaped nanoparticles with sufficiently narrow size distribution and small average size of 5.5 nm and 13.0 nm for the initial precipitation and heating process, respectively. Moreover, the synthesized calcium borate nanoparticles showed good luminescence properties with a simple glow curve dominating at 150°C.Results:This curve was utilized to derive trapping parameters including the activation energy, order of kinetic and frequency factor.Conclusion:The well-dispersed calcium borate nanoparticles have been prepared successfully by introduction of sufficient concentration of polymer.

Cobalt Metal ion Doped Cerium Oxide (Co-CeO2) Nanoparticles Effect Enhanced Photocatalytic Activity

MRS Advances ◽  
2020 ◽  
pp. 1-13
Author(s):  
G. Killivalavan ◽  
B. Sathyaseelan ◽  
G. Kavitha ◽  
I. Baskarann ◽  
K. Senthilnathan ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Metal Ion ◽  
Chemical Properties ◽  
Visible Spectrum ◽  
Average Crystallite Size ◽  
Cobalt Metal ◽  
Uv Visible ◽  
Co Precipitation ◽  
Average Size ◽  
Physical And Chemical

Abstract The REE (rare-earth-elements) cerium (Ce) is the most abundant earth-crust element and their oxides have great attention in the form of nanocrystalline nature with superior physical and chemical properties. Pure and Co (1%, 3% and 5%) doped CeO2 nanoparticles (NPs) synthesized by co-precipitation technique were characterized through X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), UV-visible spectroscopy. XRD shows face-centred-cubic (FCC) crystal symmetry with average crystallite size 6–12 nm. HRTEM exhibits almost identical cubical shaped particles with average size 4–10 nm. Tuned band-gap may be observed from UV-visible spectrum of CeO2-NPs upon Co (1%, 3% & 5%) incorporation. Enhancement of the photocatalytic activity observed for Co-doped (1%, 3% & 5%) to the degradation of methylene-blue (MB) dye under visible-light absorption.

scholarly journals Study on quenching effect of nitrite ions on zinc oxide modified by polyvinylpyrrolidone

2015 ◽  
Vol 11 (3) ◽  
Author(s):  
Ing Hua Tang ◽  
Siti Zarina Mohd So’ad ◽  
Hendrik O. Lintang ◽  
Leny Yuliati
Keyword(s):  
Zinc Oxide ◽  
Chemical Properties ◽  
Precipitation Method ◽  
Broad Absorption Band ◽  
Quenching Effect ◽  
Physical Mixing ◽  
Mixing Method ◽  
Volmer Plot ◽  
Co Precipitation ◽  
Physical And Chemical

Zinc oxide (ZnO) is appeared to be an attractive material for application for multidisciplinary fields, owing to its unique physical and chemical properties. In this study, ZnO was synthesized using the co-precipitation method, where the zinc acetate was used as the precursor. The ZnO was further modified by adding different amounts of polyvinylpyrrolidone (PVP) via simple physical mixing method to obtain PVP/ZnO composites. The ZnO and the PVP/ZnO composites were characterized using Fourier transform infrared (FTIR), diffuse reflectance ultraviolet-visible (DR UV-Vis), and fluorescence spectroscopy. The FTIR spectra detected the presence of ZnO group and the functional groups from the PVP. The PVP peaks become more apparent with the increase of the PVP amount. From the DR UV-Vis spectra, no significant change was observed after modification with the PVP, and all composites showed similar broad absorption band to that of the ZnO. The fluorescence spectra showed that the addition of PVP decreased the emission intensity and red shifted the peak wavelength, indicating certain interactions between the ZnO and the added PVP. Quenching study was investigated in the presence of nitrite ions (NO2-) with various concentrations (2-10 mM). A linear Stern-Volmer plot was observed and the highest quenching constant rate (KSV) was obtained on the PVP/ZnO sample with PVP content of 0.1 wt%. This study demonstrated that the addition of the PVP on the ZnO improved the interaction between the ZnO and the NO2-, which will be one of the important factors for sensing and catalytic applications for detection and conversion of NO2-.

scholarly journals Morphological changes of ZnO nanostructures upon addition of Trisodium Citrate (Na3C6H5O7) at different reaction temperatures

2021 ◽  
Vol 5 (1) ◽  
pp. 18-22
Author(s):  
Aqilah Kamaruzaman ◽  
Nurul Akmal Che Lah
Keyword(s):  
Size Distribution ◽  
Reaction Temperature ◽  
Morphological Changes ◽  
Chemical Properties ◽  
Trisodium Citrate ◽  
Zno Nanostructure ◽  
Mean Diameter ◽  
Mean Size ◽  
The Mean ◽  
Physical And Chemical

Due to its interesting physical and chemical properties, zinc oxide (ZnO) is considered one of the front runners of numerous metal oxide semiconductors. In this paper, ZnO nanostructure are synthesised by hydrothermal method with trisodium citrate (TC) as the emulsfying agent. The mean diameetr of ZnO nanostructure are observed with increment of reaction temperature. The mean size results into no change to mean diameter upon increment of reaction temperature but the cumulative frequencies of size distribution showing ZnO nanostructure synthesised in higher temperature to have narrower size distribution. The addition of TC also results into much smaller ZnO nanostructure with mean diameter 8nm

scholarly journals Green Synthesis of Mn + Cu Bimetallic Nanoparticles Using Vinca rosea Extract and Their Antioxidant, Antibacterial, and Catalytic Activities

Crystals ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 72
Author(s):  
Mohamad M. Ahmad ◽  
Hicham Mahfoz Kotb ◽  
Shehla Mushtaq ◽  
Mir Waheed-Ur-Rehman ◽  
Christopher M. Maghanga ◽  
...  
Keyword(s):  
Bimetallic Nanoparticles ◽  
Dye Degradation ◽  
Antibacterial Properties ◽  
Chemical Properties ◽  
Inhibition Zone ◽  
Vinca Rosea ◽  
Ft Ir ◽  
Average Size ◽  
Phytochemical Components ◽  
Physical And Chemical

This article outlines the preparation of manganese-doped copper nanoparticles (Mn + Cu NPs) using Vinca rosea (L.) leaf extract as a convenient and environmentally friendly substance. UV–vis, FT–IR, XRD, SEM–EDAX, and DLS instrumental techniques were employed to describe the physical and chemical properties of synthesized V. rosea extract-mediated Vr-Mn + Cu NPs. The synthesized Vr-Mn + Cu NPs were observed to be monodispersed and spherical, with an average size of 412 nm. The plant extract includes a variety of phytochemical components. The Vr-Mn + Cu NPs also have potential antioxidant and antibacterial properties against selected pathogens. The green synthesized Vr-Mn + Cu NPs showed a maximum inhibition zone of 16.33 ± 0.57 mm against E. coli. For dye degradation, MR, EBT, and MO showed the highest degradation percentage capabilities with Vr-Mn + Cu NP-based adsorbents, which were determined to be 78.54 ± 0.16, 87.67 ± 0.06, and 69.79 ± 0.36. The results clearly show that biosynthesized Vr-Mn + Cu NPs may be employed as an antioxidant, antibacterial, photocatalytic dye degradation, and catalytic agent, as well as being ecologically benign.

scholarly journals Magnetic Properties of NiZn Ferrite Nanofibers Prepared by Electrospinning

2019 ◽  
Vol 9 (20) ◽  
pp. 4297 ◽  
Author(s):  
Na ◽  
Kim ◽  
Song ◽  
Choi
Keyword(s):  
Magnetic Properties ◽  
Electromagnetic Interference ◽  
Polymer Concentration ◽  
Chemical Properties ◽  
Size Control ◽  
Precursor Solution ◽  
X Ray Diffraction ◽  
Crystallite Sizes ◽  
20 Nm ◽  
Physical And Chemical

When the size of a material is decreased to the nanoscale, the effects of forces that are not influential on a macroscopic scale become increasingly important and the electronic structure is improved. The material then exhibits significantly different physical and chemical properties than in the bulk state. The smaller the size of the material, the more exposure it receives to the nano effects, and the physical properties can be changed via size control. In this study, Ni0.5Zn0.5Fe2O4 ferrite nanofibers were prepared by electrospinning, and the sizes of the prepared samples were controlled to ensure different average diameters by controlling the polymer concentration of the precursor solution. Field emission scanning electron microscope images showed that the samples had average diameters of 224 to 265 nm. The single crystal phase of Ni0.5Zn0.5Fe2O4 and the different crystallite sizes of 13 to 20 nm were confirmed by X-ray diffraction analysis. The magnetization behavior of the samples was measured using a vibrating sample magnetometer and the result confirmed that the samples had different magnetic properties, according to the diameter and crystallite size of the nanofibers. This study suggests that control of magnetic properties and excellent electrical conductivity in a one-dimensional nanostructure can be positively applied to improve the performance of a filler for the electromagnetic-interference shielding film.

scholarly journals Pt Nanoparticles Supported on Nitrogen doped Carbon as an Efficient Catalyst for Decalin Dehydrogenation

2020 ◽  
Vol 194 ◽  
pp. 02025
Author(s):  
Huiru Yun ◽  
Zhuo Li ◽  
Shiguang Fan ◽  
Jian Wang ◽  
He Liu
Keyword(s):  
Chemical Properties ◽  
Pt Nanoparticles ◽  
Mesoporous Structure ◽  
Catalytic Performance ◽  
High Specific Surface Area ◽  
Efficient Catalyst ◽  
Transmission Electron ◽  
Mean Size ◽  
Nitrogen Doped Carbon ◽  
Physical And Chemical

A novel Pt/CN catalyst was synthesized by sodium borohydride treatment. The physical and chemical properties of Pt/CN catalyst were characterized by X-ray diffraction (XRD), brunner-emmet-teller (BET), transmission electron microscope (TEM) and High-resolution transmission electron microscopy (HRTEM). The characterized results showed that the catalyst has a high specific surface area, mesoporous structure and the mean size of Pt nanoparticles is 2.59 nm. Subsequently, the catalytic performance of Pt/CN catalyst for decline dehydrogenation was studied. Pt/CN catalyst exhibited excellent performance in decalin dehydrogenation with the conversion of decalin was 30.70%, and the selectivity of naphthalene was 90.86% at 200 ℃ for 150 minutes. When the reaction temperature increased to 210 ℃, the conversion of catalyst increased to 52.02%, and the selectivity of naphthalene reduced to 90.21%. The possible reason may be attributed to the difficulty in converting decalin to tetralin. This paper would provide a novel method for the synthesis of efficient dehydrogenation catalyst of decalin..

scholarly journals Removal of Elemental Mercury from Flue Gas using the Magnetic Attapulgite by Mn-Cu Oxides Modification

2021 ◽  
Author(s):  
Yifei Long ◽  
Zhong He ◽  
Xiaoyi Li ◽  
Yajie Yin ◽  
Yuan Wang ◽  
...  
Keyword(s):  
Removal Efficiency ◽  
Flue Gas ◽  
Active Sites ◽  
Chemical Properties ◽  
Elemental Mercury ◽  
Mercury Removal ◽  
Impregnation Method ◽  
Active Components ◽  
Co Precipitation ◽  
Physical And Chemical

Abstract Mercury pollution has become one of the most concerned environmental issues in the world because of its high toxicity, non-degradability and bioaccumulation. Attapulgite adsorbents modified by magnetic manganese-copper (MnxCuy-MATP) were fabricated by co-precipitation and ultrasonic impregnation method,aiming at removing Hg0 from coal-fired flue gas. BET, SEM, XRD, VSM and XPS were used to systematically explore the physical and chemical properties of the adsorbents, the effects of manganese and copper additions, reaction temperature and various components in the flue gas on the efficiency of Hg0 removal were investigated. Mn8Cu5-MATP exhibited the optimal properties, and excessive copper loadings led to the aggregation of the active components. The efficiency of mercury removal can be effectively improved by NO and HCl regardless of the absence and presence of O2, because the NO+, NO3, NO2 and Cl* produced during the reaction can promote the adsorption and oxidation of Hg0. SO2 and H2O inhibited the oxidation of Hg0 because of the competitive adsorption at the active sites, while a large amount of sulfite and sulfate were formed to block the pores. However, the introduction of copper caused the sample to obtain SO2 resistance, which resulted in a mercury removal efficiency of 84.3% even under 1500 ppm SO2. In addition, after 5 cycles of adsorption and regeneration, Mn8Cu5-MATP can still maintain excellent Hg0 removal ability. The fabricated adsorbent can save the actual production cost and effectively improve the mercury removal efficiency in sulfur-containing flue gas.

Using Granulate Composites with Calcined Phosphogypsum and Pet Additive in Asphalting

2022 ◽  
Vol 1049 ◽  
pp. 257-265
Author(s):  
Pavel Borisovich Razgovorov ◽  
Аleksey A. Ignatiev ◽  
Valeriy Michailovich Gotovtsev ◽  
Elena Aleksandrovna Vlasova
Keyword(s):  
Polyethylene Terephthalate ◽  
Raw Materials ◽  
Chemical Properties ◽  
Crushed Rock ◽  
Great Promise ◽  
X Ray Diffraction ◽  
Average Size ◽  
Tropical Climates ◽  
Physical And Chemical ◽  
And Chemical Properties

The paper discusses the change of phosphogypsum surface state produced by Apatit (Cherepovetsky branch, Vologda region) during calcination at 298-1173 K. The authors have determined the average size of its crystallites and studied the atomic composition of raw materials and finished composites that include crushed rock fraction (5-10 mm), oil bitumen, and polyethylene terephthalate additive (1.0-1.2 wt. %). The compounds present in calcined phosphogypsum have been analyzed by X-ray diffraction. The granulate was obtained by pelletizing phosphogypsum with a mixture of the above components. The paper presents the assessment of its physical and chemical properties. The granulated composites based on the specified samples of calcined phosphogypsum, bitumen, and melted polyethylene terephthalate waste show great promise for construction road works in European countries in summer and winter, as well as countries with tropical climates.

ULTRAFINE AU NANODOTS ON GRAPHENE OXIDE FOR CATALYTIC REDUCTION OF 4-NITROPHENOL

NANO ◽  
2013 ◽  
Vol 08 (03) ◽  
pp. 1350034 ◽  
Author(s):  
JIANLI CHEN ◽  
GANG CHENG ◽  
ZHUANGNAN LI ◽  
FUJUN MIAO ◽  
XIAOQIANG CUI ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Catalytic Activity ◽  
Catalytic Reduction ◽  
Synthesis Method ◽  
Chemical Properties ◽  
Electrochemical Sensing ◽  
Graphene Oxide Nanosheet ◽  
Average Size ◽  
Physical And Chemical ◽  
Au Nanodots

Graphene oxide nanosheet is an ideal platform to capture nanoparticles for highly efficient catalysis, electrochemical sensing and biosensing. In this work, we have described a simple synthesis method for preparation graphene oxide– Au nanohybrid. Au nanodots with an average size of 1.6 nm uniformly dispersed on the surface of graphene oxide. The well-defined nanostructure has been characterized by transmission electron microscopy (TEM) and atomic force microscopy (AFM). The nanohybrid also exhibits enhanced catalytic activity toward the reduction of 4-nitrophenol by NaBH4 . Comparing with pure Au nanodots and graphene oxide, graphene oxide– Au nanohybrid shows the highest catalytic activity. This approach not only suggests a wide potential application of graphene oxide nanosheet as a host material for supporting a variety of nanoparticles, but also provides a new approach for the fabrication of graphene-based nanohybrids with multiple physical and chemical properties.

Sign in / Sign up

Export Citation Format

Share Document