scholarly journals FusariumAntifungal Activities of Copper Nanoparticles Synthesized by a Chemical Reduction Method

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Pham Van Viet ◽  
Hai Thi Nguyen ◽  
Thi Minh Cao ◽  
Le Van Hieu
Keyword(s):  
Copper Nanoparticles ◽  
Reduction Method ◽  
Chemical Reduction ◽  
Fungal Growth ◽  
Spherical Shape ◽  
Xrd Analysis ◽  
Chemical Reduction Method ◽  
Transmission Electron ◽  
Ft Ir ◽  
Average Size

We report on the process of synthesizing copper nanoparticles (Cu Nps) for a short reactive time by chemical reduction method with a support of CTAB reductive agent. Their properties were determined by ultraviolet-visible (UV-Vis) absorption spectrum, the X-ray (XRD) analysis, Fourier transform infrared spectroscopy (FT-IR), and Transmission Electron Microscopy (TEM) images. The antifungal activity of Cu Nps was evaluated by testing againstFusariumsp. The Cu Nps were obtained with the average size in the range of 20–50 nm having spherical shape. The survey shows that when Cu Nps were used at 450 ppm concentration in 9-day incubation, 93.98% of fungal growth was inhibited.

scholarly journals Glycerol Valorization over ZrO2-Supported Copper Nanoparticles Catalysts Prepared by Chemical Reduction Method

Catalysts ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1040
Author(s):  
Juan Garcés ◽  
Ramón Arrué ◽  
Néstor Novoa ◽  
Andreia F. Peixoto ◽  
Ricardo J. Chimentão
Keyword(s):  
Copper Nanoparticles ◽  
Reduction Method ◽  
Chemical Reduction ◽  
X Ray Diffraction ◽  
Chemical Reduction Method ◽  
X Ray ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
Region I ◽  
Temperature Programmed

Copper nanoparticles (NPs) and ZrO2-supported copper NPs (Cu NPs/ZrO2) were synthesized via a chemical reduction method applying different pH (4, 7 and 9) and evaluated in a glycerol dehydration reaction. Copper NPs were characterized with transmission electron microscopy (TEM) and UV–vis spectroscopy. Transmission electron microcopy (TEM) results revealed a homogeneous distribution of copper NPs. A hypsochromic shift was identified with UV–vis spectroscopy as the pH of the synthesis increased from pH = 4 to pH = 9. Zirconia-supported copper NPs catalysts were characterized using N2 physisorption, X-ray diffraction (XRD), TEM, X-ray photoelectron spectroscopy (XPS), temperature-programmed reduction (TPR), temperature-programmed desorption of ammonia (NH3-TPD) and N2O chemisorption. The presence of ZrO2 in the chemical reduction method confirmed the dispersion of the copper nanoparticles. X-ray diffraction indicated only the presence of tetragonal zirconia patterns in the catalysts. XPS identified the Cu/Zr surface atomic ratio of the catalysts. TPR patterns showed two main peaks for the Cu NPS/ZrO2 pH = 9 catalyst; the first peak between 125 and 180 °C (region I) was ascribed to more dispersed copper species, and the second one between 180 and 250 °C (region II) was assigned to bulk CuO. The catalysts prepared at pH = 4 and pH = 7 only revealed reduction at lower temperatures (region I). Copper dispersion was determined by N2O chemisorption. With NH3-TPD it was found that Cu NPs/ZrO2 pH = 9 exhibited the highest total quantity of acidic sites and the highest apparent kinetic constant, with a value of 0.004 min−1. The different pH applied to the synthesis media of the copper nanoparticles determined the resultant copper dispersion on the ZrO2 support, providing active domains for glycerol conversion.

Formation of Platinum Nanodendrites Embedded Organic Insulator for Memory Application

2014 ◽  
Vol 1024 ◽  
pp. 44-47 ◽  
Author(s):  
Nur Syafinaz Ridhuan ◽  
Nabil Iman Muzzafaruddin ◽  
Abdul Razak Khairunisak ◽  
K.C. Aw
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Reduction Method ◽  
Chemical Reduction ◽  
Chemical Reduction Method ◽  
Growth Duration ◽  
X Ray ◽  
Transmission Electron ◽  
Average Size ◽  
Memory Characteristics

This work describes the formation of platinum nanodendrites (PtNDs) using the chemical reduction method. The PtNDs were formed with varying concentration of K2PtCl4 precursor (5-20 mM) and growth duration (8-16 min). The optimum concentration of K2PtCl4 was 15 mM whereby high crystalline nanodendrites with an average size of 118 nm were produced. Aggregation of nanodendrites occurred when the growth duration was prolonged to more than 12 minutes. The morphology and size of PtNDs were characterized by using a transmission electron microscope (TEM), high resolution transmission electron microscope (HRTEM) and X-ray diffractometer (XRD). Additionally, the memory characteristics of PtNDs embedded in polymethylsilsesquioxanes (PMSSQ)/Si with gold electrodes were studied in this work. PtNDs played a role as charge-trapped sites and showed good memory effect when embedded in PMSSQ. Optimum memory properties of PMSSQ-embedded PtNDs were obtained for PtNDs synthesized with 15 mM K2PtCl4 concentration at 12 min of growth duration with 170 electrons trapped per PtNDs and Vth of 2.8 V.

Preparation of Fe3O4-Coated Microsilica Composites via Chemical Reduction Method

2013 ◽  
Vol 750-752 ◽  
pp. 1071-1074
Author(s):  
Hui Xia Feng ◽  
Bai Yi Chen ◽  
De Yi Zhang ◽  
Jian Qiang Zhang ◽  
He Ming Luo
Keyword(s):  
Electron Microscope ◽  
Reduction Method ◽  
Chemical Reduction ◽  
Vibrating Sample Magnetometer ◽  
Chemical Reduction Method ◽  
Magnetic Composites ◽  
X Ray ◽  
The Core ◽  
Transmission Electron ◽  
Novel Method

Fe3O4-coated microsilica composites were synthesized by a novel method. The struction like precursor Fe3O4 nanoparticles as the shell and microsillica as the core for the composite has been prepared by chemical reduction method. The Fe3O4-coated microsilica composite presents a saturation magnetization value of 38.03 emu/g, which is sufficient to complete magnetic separation. The synthesized magnetic composites are characterized by X-ray diffractometer (XRD), transmission electron microscope (TEM) and vibrating sample magnetometer (VSM). The results indicated that Fe3O4 nanoparticles successfully coated on microsilica.

Seed mediated copper nanoparticle synthesis for fabricating oxidation free interdigitated electrodes using intense pulse light sintering for flexible printed chemical sensors

2017 ◽  
Vol 5 (42) ◽  
pp. 11128-11137 ◽  
Author(s):  
Krishnamraju Ankireddy ◽  
Thad Druffel ◽  
Swathi Vunnam ◽  
Gregor Filipič ◽  
Ruvini Dharmadasa ◽  
...  
Keyword(s):  
Copper Nanoparticles ◽  
Chemical Sensors ◽  
Reduction Method ◽  
Chemical Reduction ◽  
Nanoparticle Synthesis ◽  
Intense Pulse Light ◽  
Copper Nanoparticle ◽  
Chemical Reduction Method ◽  
Interdigitated Electrodes ◽  
Seed Mediated

A facile aqueous-based seed-mediated chemical reduction method is developed for the synthesis of copper nanoparticles.

scholarly journals Green Synthesis of Silver Nanoparticles and Their Bactericidal and Antimycotic Activities against Oral Microbes

2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Osvelia E. Rodríguez-Luis ◽  
Rene Hernandez-Delgadillo ◽  
Rosa Isela Sánchez-Nájera ◽  
Gabriel Alejandro Martínez-Castañón ◽  
Nereyda Niño-Martínez ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Fungal Growth ◽  
Spherical Shape ◽  
Xrd Analysis ◽  
Glycyrrhiza Glabra ◽  
X Ray Diffraction ◽  
Synthesize Silver Nanoparticles ◽  
Oral Biofilms ◽  
Oral Microbes ◽  
Average Size

Nanotechnology is a new discipline with huge applications including medicine and pharmacology industries. Although several methods and reducing agents have been employed to synthesize silver nanoparticles, reactive chemicals promote toxicity and nondesired effects on the human and biological systems. The objective of this work was to synthesize silver nanoparticles fromGlycyrrhiza glabraandAmphipterygium adstringensextracts and determine their bactericidal and antimycotic activities againstEnterococcus faecalisandCandida albicansgrowth, respectively. 1 and 10 mM silver nitrate were mixed with an extract ofGlycyrrhiza glabraandAmphipterygium adstringens.Green silver nanoparticles (AgNPs) were characterized by TEM, Vis-NIR, FTIR, fluorescence, DLS, TGA, and X-ray diffraction (XRD) analysis. Bactericidal and antimycotic activities of AgNPs were determined by Kirby and Bauer method and cell viability MTT assays. AgNPs showed a spherical shape and average size of 9 nm if prepared withGlycyrrhiza glabraextract and 3 nm if prepared withAmphipterygium adstringensextract. AgNPs inhibited the bacterial and fungal growth as was expected, without a significant cytotoxic effect on human epithelial cells. Altogether, these results strongly suggest that AgNPs could be an interesting option to control oral biofilms.

scholarly journals Enhancing Photocatalytic Degradation of Methyl Blue Using PVP-Capped and Uncapped CdSe Nanoparticles

2017 ◽  
Vol 2017 ◽  
pp. 1-6 ◽  
Author(s):  
Kgobudi Frans Chepape ◽  
Thapelo Prince Mofokeng ◽  
Pardon Nyamukamba ◽  
Kalenga Pierre Mubiayi ◽  
Makwena Justice Moloto
Keyword(s):  
Photocatalytic Degradation ◽  
Reduction Method ◽  
Organic Dyes ◽  
Chemical Reduction ◽  
Cdse Nanoparticles ◽  
Methyl Blue ◽  
Simple Type ◽  
Chemical Reduction Method ◽  
Tem Analysis ◽  
Transmission Electron

Quantum confinement of semiconductor nanoparticles is a potential feature which can be interesting for photocatalysis, and cadmium selenide is one simple type of quantum dot to use in the following photocatalytic degradation of organic dyes. CdSe nanoparticles capped with polyvinylpyrrolidone (PVP) in various concentration ratios were synthesized by the chemical reduction method and characterized. The transmission electron microscopy (TEM) analysis of the samples showed that 50% PVP-capped CdSe nanoparticles were uniformly distributed in size with an average of 2.7 nm and shape which was spherical-like. The photocatalytic degradation of methyl blue (MB) in water showed efficiencies of 31% and 48% when using uncapped and 50% PVP-capped CdSe nanoparticles as photocatalysts, respectively. The efficiency of PVP-capped CdSe nanoparticles indicated that a complete green process can be utilized for photocatalytic treatment of water and waste water.

scholarly journals Silver Nanoparticle-Based Paper Packaging to combat Black Anther Disease in Orchid Flowers

2018 ◽  
Author(s):  
Bang-on Nokkrut ◽  
Sawitree Pisuttipiched ◽  
Somwang Khantayanuwong ◽  
Buapan Puangsin
Keyword(s):  
Water Resistance ◽  
Reduction Method ◽  
Chemical Reduction ◽  
Metal Nanoparticle ◽  
Chemical Reduction Method ◽  
High Antimicrobial Activity ◽  
Coating Solution ◽  
Atomic Force ◽  
Vis Spectroscopy ◽  
Average Size

Metal nanoparticle has been reported to have a high antimicrobial activity against fungi, bacteria, and yeasts. In this study, silver nanoparticles (AgNPs) were synthesized using a chemical reduction method, at 90 oC, and used as an antifungal coating in paper packaging, to control the growth of C. gloeosporioides in cut orchid flowers during shipping. AgNPs were characterized by UV-Vis spectroscopy and atomic force microscope (AFM). The results indicated that the shape of AgNPs was spherical and homogenous with an average size of 47 nm. Twenty and 50 particles per million (ppm) concentration of AgNPs, mixed with starch, were prepared as the coating solution. The paper coated with 50 ppm AgNPs exhibited a significant antifungal activity against C. gloeosporioides compared to 20 ppm AgNPs coating. The AgNPs coated paper had a better water resistance and mechanical properties compared to paper without coating. We observed a significant reduction in the number of anthers, of orchid inflorescences, infected by C. gloeosporioides, when stored in the coated boxes. The current study demonstrates that paper boxes coated with AgNPs are a potential solution to control the infection of C. gloeosporioides in the storage of cut orchid flowers.

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