scholarly journals Synthesis of nanomaterials using expired medicines: an eco-friendly option

2012 ◽  
Vol 2 (1) ◽  
pp. 7 ◽  
Author(s):  
Anal K. Jha ◽  
Kamal Prasad
Keyword(s):  
Single Step ◽  
Molecular Organization ◽  
Cds Nanoparticles ◽  
X Ray Diffraction ◽  
Green Approach ◽  
Transmission Electron ◽  
Novel Method ◽  
Molecular Forces ◽  
First Time ◽  
Expired Medicines

Expired medicines are a burden to the environment. In this paper, a novel method is suggested to reutilize expired medicines in order to assess the possibilities of synthesizing a variety of nanomaterials. To this end, expired flouroquinolone (norfloxacin) and tinidazole combinations were used to synthesize metal (Au), oxide (ZrO<sub>2</sub>) and chalcognide (CdS) nanoparticles using for the first time a green chemistry approach. Au, ZrO<sub>2</sub> and CdS nanoparticles are available in convenient sizes of 6 nm, 26 nm and 18 nm, respectively, and remain stable for at least six months. This novel procedure is possible thanks to their molecular organization and elements. The inclusion of a fluorine atom in a drug molecule may influence both the disposition of the drug and its interaction with its pharmacological target; for example, the effects of fluorine substitution on the inter- and intra-molecular forces that affect binding of ligands. The presence of sulfur in the tinidazole molecules may also have contributed towards synthesis through proton withdrawal. The nanomaterials synthesized in this way were characterized using X-ray diffraction analysis and transmission electron microscopy to identify the formation of the desired nanoparticles. This single-step green approach is very convenient, simple and can be extended to synthesize a variety of nanomaterials that might find new technological and pharmaceutical applications.

SYNTHESIS, CHARACTERIZATION AND PHOTOCATALYTIC ACTIVITIES OF Ba2YbZrO5.5 NANOPARTICLES UNDER SOLAR IRRADIATION

NANO ◽  
2011 ◽  
Vol 06 (03) ◽  
pp. 279-286 ◽  
Author(s):  
V. RATHEESH KUMAR ◽  
V. S. PRASAD ◽  
P. R. S. WARIAR ◽  
J. KOSHY
Keyword(s):  
Combustion Process ◽  
Visible Spectrum ◽  
Single Step ◽  
Solar Irradiation ◽  
X Ray Diffraction ◽  
Selected Area Electron Diffraction ◽  
Transmission Electron ◽  
Photocatalytic Activities ◽  
20 Nm ◽  
First Time

The complex perovskite Ba2YbZrO5.5 has been successfully synthesized as nanoparticles through a single step combustion process for the first time. The X-ray diffraction analysis revealed that the combustion product is phase-pure and has an ordered cubic perovskite structure. Transmission electron microscopy results indicated that the particle sizes are 10–20 nm. The selected area electron diffraction pattern has shown that as-prepared powder is polycrystalline in nature. The UV–visible spectrum analysis confirmed that the optical absorption edge of Ba2YbZrO5.5 is around 340 nm, corresponding to a band gap of ~ 3.65 eV. Photocatalytic activity of Ba2YbZrO5.5 nanoparticles is investigated for the degradation of methyl orange under solar irradiation.

scholarly journals Quartz Crystallite Size and Moganite Content as Indicators of the Mineralogical Maturity of the Carboniferous Chert: The Case of Cherts from Eastern Asturias (Spain)

Minerals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 611
Author(s):  
Celia Marcos ◽  
María de Uribe-Zorita ◽  
Pedro Álvarez-Lloret ◽  
Alaa Adawy ◽  
Patricia Fernández ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Crystallite Size ◽  
Archaeological Sites ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Infrared And Raman Spectroscopy ◽  
First Time ◽  
Geological Formations

Chert samples from different coastal and inland outcrops in the Eastern Asturias (Spain) were mineralogically investigated for the first time for archaeological purposes. X-ray diffraction, X-ray fluorescence, transmission electron microscopy, infrared and Raman spectroscopy and total organic carbon techniques were used. The low content of moganite, since its detection by X-ray diffraction is practically imperceptible, and the crystallite size (over 1000 Å) of the quartz in these cherts would be indicative of its maturity and could potentially be used for dating chert-tools recovered from archaeological sites. Also, this information can constitute essential data to differentiate the cherts and compare them with those used in archaeological tools. However, neither composition nor crystallite size would allow distinguishing between coastal and inland chert outcrops belonging to the same geological formations.

scholarly journals The Effect of Surfactant-Modified Montmorillonite on the Cross-Linking Efficiency of Polysiloxanes

Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2623
Author(s):  
Monika Wójcik-Bania ◽  
Jakub Matusik
Keyword(s):  
Total Pore Volume ◽  
Cross Linking ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
The Cross ◽  
Chain Lengths ◽  
First Time ◽  
Substituent Influence ◽  
Benzyl Substituent

Polymer–clay mineral composites are an important class of materials with various applications in the industry. Despite interesting properties of polysiloxanes, such matrices were rarely used in combination with clay minerals. Thus, for the first time, a systematic study was designed to investigate the cross-linking efficiency of polysiloxane networks in the presence of 2 wt % of organo-montmorillonite. Montmorillonite (Mt) was intercalated with six quaternary ammonium salts of the cation structure [(CH3)2R’NR]+, where R = C12, C14, C16, and R’ = methyl or benzyl substituent. The intercalation efficiency was examined by X-ray diffraction, CHN elemental analysis, and Fourier transform infrared (FTIR) spectroscopy. Textural studies have shown that the application of freezing in liquid nitrogen and freeze-drying after the intercalation increases the specific surface area and the total pore volume of organo-Mt. The polymer matrix was a poly(methylhydrosiloxane) cross-linked with two linear vinylsiloxanes of different siloxane chain lengths between end functional groups. X-ray diffraction and transmission electron microscopy studies have shown that the increase in d-spacing of organo-Mt and the benzyl substituent influence the degree of nanofillers’ exfoliation in the nanocomposites. The increase in the degree of organo-Mt exfoliation reduces the efficiency of hydrosilylation reaction monitored by FTIR. This was due to physical hindrance induced by exfoliated Mt particles.

scholarly journals A REVIEW: A GREEN APPROACH FOR THE SYNTHESIS OF SILVER NANOPARTICLES AND ITS ANTIBACTERIAL APPLICATIONS

2018 ◽  
Vol 11 (8) ◽  
pp. 74 ◽  
Author(s):  
Shyla Marjorie Haqq ◽  
Amit Chattree
Keyword(s):  
Silver Nanoparticles ◽  
Antimicrobial Properties ◽  
Nanoparticle Synthesis ◽  
Silver Ions ◽  
Multidrug Resistant ◽  
X Ray Diffraction ◽  
Green Approach ◽  
Transmission Electron ◽  
Uv Visible ◽  
Silver Nanoparticle Synthesis

  This review is based on the synthesis of silver nanoparticles (AgNPs) using a green approach which is biofabricated from various medicinal plants. AgNPs were prepared from the various parts of the plants such as the flowers, stems, leaves, and fruits. Various physiochemical characterizations were performed using the ultraviolet (UV)-visible spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction spectroscopy, transmission electron microscopy, and energy dispersive spectroscopy. AgNPs were also used to inhibit the growth of bacterial pathogens and were found to be effective against both the Gram-positive and Gram-negative bacteria. For the silver to have antimicrobial properties, it must be present in the ionized form. All the forms of silver-containing compounds with the observed antimicrobial properties are in one way or another source of silver ions. Although the antimicrobial properties of silver have been known, it is thought that the silver atoms bind to the thiol groups in enzymes and subsequently leads to the deactivation of enzymes. For the silver to have antimicrobial properties, it must be present in the ionized form. The study suggested that the action of the AgNPs on the microbial cells resulted into cell lysis and DNA damage. AgNPs have proved their candidature as a potential antibacterial against the multidrug-resistant microbes. The biological agents for synthesizing AgNPs cover compounds produced naturally in microbes and plants. Reaction parameters under which the AgNPs were being synthesized hold prominent impact on their size, shape, and application. Silver nanoparticle synthesis and their application are summarized and critically discussed in this review.

Facile Refluxing Synthesis of Hydroxyapatite Nanoparticles

2015 ◽  
Vol 68 (8) ◽  
pp. 1293 ◽  
Author(s):  
Pakvipar Chaopanich ◽  
Punnama Siriphannon
Keyword(s):  
Crystallite Size ◽  
Reaction Times ◽  
Single Step ◽  
Hydroxyapatite Nanoparticles ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Aqueous Mixture ◽  
Diffraction Patterns ◽  
Microscopy Images

Hydroxyapatite (HAp) nanoparticles were successfully synthesized from an aqueous mixture of Ca(NO3)2·4H2O and (NH4)2HPO4 by a facile single-step refluxing method using polystyrene sulfonate (PSS) as a template. The effects of reaction times, pH, and PSS concentration on the HAp formation were investigated. It was found that the crystalline HAp was obtained under all conditions after refluxing the precursors for 3 and 6 h. The longer refluxing time, the greater the crystallinity and the larger the crystallite size of the HAp nanoparticles. The HAp with poor crystallinity was obtained at pH 8.5; however, the well-crystallized HAp was obtained when reaction pH was increased to 9.5 and 10.5. In addition, the X-ray diffraction patterns revealed that the presence of PSS template caused the reduction of HAp crystallite size along the (002) plane from 52.6 nm of non-template HAp to 43.4 nm and 41.4 nm of HAp with 0.05 and 0.2 wt-% PSS template, respectively. Transmission electron microscopy images of the synthesized HAp revealed the rod-shaped crystals of all samples. The synthesized HAp nanoparticles were modified by l-aspartic acid (Asp) and l-arginine (Arg), having negative and positive charges, respectively. It was found that the zeta potential of HAp was significantly changed from +5.46 to –24.70 mV after modification with Asp, whereas it was +4.72 mV in the Arg-modified HAp. These results suggested that the negatively charged amino acid was preferentially adsorbed onto the synthesized HAp surface.

Boron Nitride Nanotubes: Nanoparticles Functionalization and Junction Fabrication

2007 ◽  
Vol 7 (2) ◽  
pp. 530-534 ◽  
Author(s):  
Chunyi Zhi ◽  
Yoshio Bando ◽  
Guozhen Shen ◽  
Chengchun Tang ◽  
Dmitri Golberg
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Boron Nitride ◽  
Boron Nitride Nanotubes ◽  
X Ray Diffraction ◽  
Carbon Nanostructure ◽  
Wet Chemistry ◽  
X Ray ◽  
Transmission Electron ◽  
First Time

Adopting a wet chemistry method, Au and Fe3O4 nanoparticles were functionalized on boron nitride nanotubes (BNNTs) successfully for the first time. X-ray diffraction pattern and transmission electron microscopy were used to characterize the resultant products. Subsequently, a method was proposed to fabricate heterojunction structures based on the particle-functionalized BNNTs. As a demonstration, BNNT-carbon nanostructure, BNNT-ZnO and BNNT-Ga2O3 junctions were successfully fabricated using the functionalized particles as catalysts.

An expeditious one-pot synthesis of pyrido[2,3-d]pyrimidines using Fe3O4–ZnO–NH2–PW12O40 nanocatalyst

2019 ◽  
Vol 43 (3-4) ◽  
pp. 135-139
Author(s):  
Pegah Farokhian ◽  
Manouchehr Mamaghani ◽  
Nosrat Ollah Mahmoodi ◽  
Khalil Tabatabaeian ◽  
Abdollah Fallah Shojaie
Keyword(s):  
Electron Microscopy ◽  
Vibrating Sample Magnetometer ◽  
X Ray Diffraction ◽  
Facile Synthesis ◽  
Pyrimidine Derivatives ◽  
One Pot ◽  
X Ray ◽  
Transmission Electron ◽  
Novel Method ◽  
Operational Simplicity

An efficient protocol for the facile synthesis of a series of pyrido[2,3- d]pyrimidine derivatives has been developed applying Fe3O4–ZnO–NH2–PW12O40 nanocatalyst in water. This novel method has the benefits of operational simplicity, green aspects by avoiding toxic solvents and high to excellent yields of products. Fe3O4–ZnO–NH2–PW12O40 was synthesized and characterized by Fourier transform infrared, X-ray diffraction, vibrating sample magnetometer, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and transmission electron microscopy analyses. The nanocatalyst is readily isolated and recovered from the reaction mixture by an external magnet.

scholarly journals Formation of ZnO/Zn0.5Cd0.5Se Alloy Quantum Dots in the Presence of High Oleylamine Contents

Nanomaterials ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 999
Author(s):  
Yi-An Chen ◽  
Kuo-Hsien Chou ◽  
Yi-Yang Kuo ◽  
Cheng-Ye Wu ◽  
Po-Wen Hsiao ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Quantum Dots ◽  
Particle Size ◽  
X Ray Diffraction ◽  
One Pot ◽  
X Ray ◽  
Transmission Electron ◽  
Average Size ◽  
Alloy Quantum Dots ◽  
First Time

To the best of our knowledge, this report presents, for the first time, the schematic of the possible chemical reaction for a one-pot synthesis of Zn0.5Cd0.5Se alloy quantum dots (QDs) in the presence of low/high oleylamine (OLA) contents. For high OLA contents, high-resolution transmission electron microscopy (HRTEM) results showed that the average size of Zn0.5Cd0.5Se increases significantly from 4 to 9 nm with an increasing OLA content from 4 to 10 mL. First, [Zn(OAc)2]–OLA complex can be formed by a reaction between Zn(OAc)2 and OLA. Then, Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) data confirmed that ZnO is formed by thermal decomposition of the [Zn(OAc)2]–OLA complex. The results indicated that ZnO grew on the Zn0.5Cd0.5Se surface, thus increasing the particle size. For low OLA contents, HRTEM images were used to estimate the average sizes of the Zn0.5Cd0.5Se alloy QDs, which were approximately 8, 6, and 4 nm with OLA loadings of 0, 2, and 4 mL, respectively. We found that Zn(OAc)2 and OLA could form a [Zn(OAc)2]–OLA complex, which inhibited the growth of the Zn0.5Cd0.5Se alloy QDs, due to the decreasing reaction between Zn(oleic acid)2 and Se2−, which led to a decrease in particle size.

Direct Preparation of Ce0.8Sm0.2O1.9 Powders Oxidized With H2O2 for Low Temperature SOFCs Application

2005 ◽  
Author(s):  
Jianbing Huang ◽  
Zongqiang Mao ◽  
Bin Zhu ◽  
Lizhai Yang ◽  
Ranran Peng ◽  
...  
Keyword(s):  
Single Phase ◽  
Fluorite Structure ◽  
X Ray Diffraction ◽  
Composite Electrolyte ◽  
Xrd Pattern ◽  
Transmission Electron ◽  
Direct Preparation ◽  
Novel Method ◽  
Power Densities

A novel method was developed to prepare fine doped ceria (DCO) powders directly. Ceria doped with 20 mol. % of samarium (Ce0.8Sm0.2O1.9, SDC) was prepared by in-situ oxidization of hydroxide precipitates with H2O2 in the solutions. The resultant powder desiccated at 85°C overnight was characterized by X-ray diffraction (XRD), thermogravimetry /differential thermal analysis (TG/DTA), and transmission electron microscopy (TEM). The XRD pattern showed that the as-dried SDC powder is single phase with a cubic fluorite structure like that of pure CeO2. An anode-supported SOFC was also fabricated based on SDC and 20wt. % (62mol. %Li2CO3–38 mol. %K2CO3) composite electrolyte, LiNiO2 as cathode and NiO as anode, by cold pressing. Using hydrogen as the fuel and air as the oxidant, the I-V and I-P characteristics exhibit excellent performances and the maximum power densities are about 696, 469, 377 and 240 mWcm−2 at 650, 600, 550 and 500°C, respectively.

scholarly journals Development of a Novel Method for the Fabrication of Nanostructured Zr(x)Ni(y) Catalyst to Enhance the Desorption Properties of MgH2

Catalysts ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 849
Author(s):  
Gracia Shokano ◽  
Zahir Dehouche ◽  
Basile Galey ◽  
Georgeta Postole
Keyword(s):  
Hydrogen Desorption ◽  
Milling Process ◽  
Hydrogen Release ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Electron Microscope Analysis ◽  
Novel Method ◽  
Temperature Programmed ◽  
The Impact

The present work involves the development of a novel method for the fabrication of zirconium nickel (Zr(x)Ni(y)) alloy used as a nanocatalyst to improve the hydrogen storage properties of the Mg/MgH2 system. The catalyst was fabricated through the high-pressure reactor and activated under hydrogen prior to being mechanically milled with the MgH2 for 5 h under argon. The microstructure characterisation of the samples was determined via SEM-EDX (scanning electron microscope analysis–energy dispersive X-ray spectroscopy), XRD (X-ray diffraction) and FE-HRTEM (field emission high resolution transmission electron microscopy), and the desorption characteristic of the nanocomposite (10 wt.% Zr(x)Ni(y)–MgH2) was determined via TPD (temperature-programmed desorption). The nanostructured MgH2 powder milled with 10 wt.% of the activated Zr(x)Ni(y) based nanocatalyst resulted in a faster hydrogen release—5.9 H2-wt.% at onset temperature 210 °C/peak temperature 232 °C. The observed significant improvement in the hydrogen desorption properties was likely to be the result of the impact of the highly dispersed catalyst on the surface of the Mg/MgH2 system, the reduction in particle size during the ball milling process and/or the formation of Mg0.996Zr0.004 phase during the milling process.

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