scholarly journals Development of magnetic nanoparticles Fe+32 X+21O4 (X= Fe, Co y Ni) coated by amino silane

2017 ◽  
Author(s):  
◽  
I. A. Flores-Urquizo
Keyword(s):  
Magnetic Nanoparticles ◽  
Crystal Size ◽  
Organic Molecules ◽  
Magnetic Core ◽  
Stoichiometric Ratio ◽  
Vibrational Modes ◽  
X Ray Diffraction ◽  
X Ray ◽  
Amino Silane ◽  
Diffraction Patterns

Magnetic nanoparticles are proposed as heat mediators in hyperthermia treatments. In this work, three core-shell materials of different composition and magnetic anisotropy were developed to determine their properties as crystal size, saturation magnetization and their coating with organic molecules. The magnetic core of these materials was made by means of the coprecipitation reaction, following the stoichiometric ratio X+2Fe2+3O4 where X is Fe, Co or Ni for each material. From the X-ray diffraction patterns the crystal size of each material was determined, these were 10.39 nm, 7.27 nm y 3.86 nm. In addition, magnetization was 55.84 emu/g, 36.56 emu/g y 16.21 emu/g for magnetite, cobalt ferrite and nickel respectively. Each material was coated with aminosilane and by FTIR the vibrational modes of the C-N, N-H, C-H and Si-O bonds involved in the coating were identified.

Radiolabeled D-Penicillamine Magnetic Nanocarriers for Targeted Purposes

2016 ◽  
Vol 16 (4) ◽  
pp. 4174-4179 ◽  
Author(s):  
Seniha Yolcular Özyüncü ◽  
Serap Teksöz ◽  
Çiğdem İçhedef ◽  
E. İlker Medine ◽  
Çığır Biray Avcı ◽  
...  
Keyword(s):  
Magnetic Nanoparticles ◽  
Human Breast ◽  
X Ray Diffraction ◽  
Mcf7 Cells ◽  
New Agents ◽  
X Ray ◽  
Amino Silane ◽  
Magnetic Nanocarriers ◽  
New Occurrences

The aim of this study is to synthesize D-Penicillamine (D-PA) conjugated magnetic nanocarriers for targeted purposes. Magnetic nanoparticles were prepared by partial reduction method and surface modification was done with an amino silane coupling agent’s (structural properties), AEAPS, the particles were characterized by Scanning Electron Microscope (SEM), X-ray Diffraction (XRD). After that D-PA was linked with the magnetic nanoparticles (MNPs) and has been radiolabeled with [99mTc(CO)3]+ core. Quality controls of [99mTc(CO)3-MNP-D-PA] were established by Cd(Te) detector. The radiolabeling efficiency of magnetic nanoparticles ([99mTc(CO)3-MNP-D-PA]) was about 97.05% with good in vitro stability during the 24 hour period. As a parallel study, radiolabeled D-PA complex ([99mTc(CO)3-D-PA]) was prepared with a radiolabeling yield of 97.93%. At the end, biologic activities of binding complexes were investigated on MCF7 human breast cancer cells. Our results show that, radiolabeled magnetic nanoparticles with core [99mTc(CO)3]+ ([99mTc(CO)3-MNP-D-PA]) showed the highest uptake on MCF7 cells which were applied magnetic field in the wells. In that case, result of this study emphasizes that radiolabeled magnetic nanoparticles with core [99mTc(CO)3]+ would support new occurrences of new agents.

Preparation and Application of Carboxyl-Functioned Magnetic Nanoparticles for Arylsulfatase Immobilization

2016 ◽  
Vol 13 (10) ◽  
pp. 7408-7415
Author(s):  
Yongxing Li ◽  
Qiong Xiao ◽  
Qin Yin ◽  
Hui Ni ◽  
Yanbing Zhu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Magnetic Nanoparticles ◽  
Vibrating Sample Magnetometry ◽  
X Ray Diffraction ◽  
Sulfate Ester ◽  
Xrd Pattern ◽  
X Ray ◽  
Transmission Electron ◽  
Mean Diameter ◽  
Diffraction Patterns

Arylsulfatase, one of a few enzymes that can enhance the gelling strength of agar by cleaving the sulfate ester bonds in agar, was covalently immobilized with carboxyl functioned magnetic nanoparticles (CMNPs). The resultant CMNPs and immobilized arylsulfatase were characterized by transmission electron microscopy (TEM), Dynamic Light scattering (DLS), X-ray diffraction (XRD), vibrating sample magnetometry (VSM) and thermogravimetric analysis (TGA). The TEM result indicated that the CMNPs and immobilized arylsulfatase had a similar mean particle size of 10 nm. The arylsulfatase-CMNPs had a mean diameter of 1200 nm in aqueous solution determined by the DLS, which was much bigger than the CMNPs (433.6 nm). The different sizes demonstrated that the arylsulfatase was coated on CMNPs successfully. XRD showed that diffraction patterns of the CMNPs and arylsulfatase-CMNPs were close to the standard XRD pattern of Fe3O4. Saturation magnetizations were 52.1 emu/g for carriers and 47.9 emu/g for immobilized arylsulfatase, which indicated that the particles had superparamagnetic characteristics. The TGA revealed that the amount of arylsulfatase bound to the surface of CMNPs was 5.65%. The arylsulfatase exhibited better thermal stability and reusability after immobilization, the immobilized arylsulfatase can retain more than 50% enzyme activity up to the 9th cycle.

scholarly journals Effect of the Nano Crystal Size on the X-ray Diffraction Patterns of Biogenic Hydroxyapatite from Human, Bovine, and Porcine Bones

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Sandra M. Londoño-Restrepo ◽  
Rodrigo Jeronimo-Cruz ◽  
Beatriz M. Millán-Malo ◽  
Eric M. Rivera-Muñoz ◽  
Mario E. Rodriguez-García
Keyword(s):  
Crystal Size ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diffraction Patterns ◽  
Nano Crystal ◽  
Biogenic Hydroxyapatite

scholarly journals Determination of crystal size distribution by two-dimensional X-ray diffraction

2014 ◽  
Vol 70 (a1) ◽  
pp. C1131-C1131
Author(s):  
Alejandro Rodriguez-Navarro ◽  
Krzysztof Kudłacz
Keyword(s):  
Size Distribution ◽  
Crystal Size ◽  
High Sensitivity ◽  
Crystal Size Distribution ◽  
Polycrystalline Materials ◽  
Two Dimensional ◽  
X Ray Diffraction ◽  
X Ray ◽  
Area Detector ◽  
Diffraction Patterns

Polycrystalline materials properties and behaviour are ultimately determined by their crystallinity, phase composition and microstructure (i.e., crystal size, preferential orientation). Two-dimensional (2D) diffraction patterns collected with an area detector (i.e., CDD), available in modern X-ray diffractometers, contain detailed information about all these important material characteristics. Furthermore, recent advances in detector technologies permits the collection of high resolution diffraction patterns in which the microstructure of the material can be directly imaged. If the size of beam relative to the crystal size in the sample is adequately choosen, the diffraction pattern produced will have spotty rings in which the spots are the diffracted images of individual grains. The resolution of the image is mainly dependent on the characteristics of the X-ray beam (i.e., diameter, angular divergence), which can be modulated by X-ray optics, sample to detector distance, the pixel size of the detector and the sharpness of the point spread function. From these patterns, the crystal size distribution of different crystalline phases present in the sample can be independently determined using specialized software capable of extracting and combining the information contained in these patterns. This technique is applicable to materials with crystal sizes ranging from submicron to mm sizes and is complementary to techniques based on peak profile analyses (i.e., Scherrer method) which are applicable only to nanocrystalline materials. Finally, given the high sensitivity of current detectors, crystal size evolution can be followed in real-time to study important transformation processes such as crystallization, annealing, etc. The use of 2D X-ray diffraction as applied to microstructure characterization will be illustrated through several examples.

Studi Difraksi Sinar-X Struktur Nano Seng Oksida (ZnO)

2018 ◽  
Vol 2 (2) ◽  
pp. 53-57
Author(s):  
Suhufa Alfarisa ◽  
Dwi Ahmad Rifai ◽  
Parmin Lumban Toruan
Keyword(s):  
Diffraction Study ◽  
Crystallite Size ◽  
Crystal Size ◽  
Sonochemical Method ◽  
Sonication Time ◽  
X Ray Diffraction ◽  
Nano Zno ◽  
X Ray ◽  
Zno Nanostructure ◽  
Diffraction Patterns

Abstrak – Kajian terhadap difraksi sinar-X struktur nano ZnO dengan waktu sonikasi yang berbeda telah dilakukan menggunakan metode hidrotermal-sonokimia. Variasi waktu sonikasi yang digunakan dalam kajian ini adalah 0 (tanpa sonikasi), 30, 45, dan 60 menit. Pola difraksi sinar-X diplotkan dan dibandingkan untuk mengetahui struktur, kristalinitas dan kemurnian ZnO yang dihasilkan. Estimasi ukuran kristal ZnO juga dihitung menggunakan persamaan Scherrer. Hasil penelitian menunjukkan bahwa struktur nano ZnO yang disintesis tanpa proses sonikasi memiliki kemurnian kristal yang rendah dengan ukuran kristal yang sedang berkisar dari 22,36 – 32,90 nm. Proses sonikasi telah menyebabkan kristalinitas dan kemurnian ZnO meningkat jadi lebih baik. Namun, memperpanjang waktu sonikasi hingga 45 sampai 60 menit menyebabkan membesarnya ukuran kristal ZnO. Waktu sonikasi yang paling optimal adalah 30 menit dimana mampu menghasilkan ZnO dengan kristalinitas dan kemurnian yang baik dan rentang ukuran kristal ZnO yang lebih kecil antara 22,09 – 21,97 nm.                                                                                   Kata kunci: difraksi sinar-X, struktur nano, ZnO, sonikasi, Scherrer Abstract – Research on the X-ray diffraction study of ZnO nanotructure synthesized at different sonication times has been done using hydrothermal-sonochemical method. Sonication variation times that were used in this study were 0 (without sonication), 30, 45, and 60 minutes. The X-ray diffraction patterns were plotted and compared to understand the structure, crystallinity and purity of the resulted ZnO. The estimated crystallite size of ZnO nanostructure were also calculated using Scherrer equation. The results showed that the ZnO nanostructure synthesized without sonication process has a low crystal purity and a fair crystallite size in the range of 22.36 - 32.90 nm. Sonication process has led to a better crystallinity and purity of ZnO. However, longer sonication times up to 45 to 60 minutes has caused to the larger crystal size of ZnO. The most optimum sonication time was found to be 30 minutes which resulted in a good crstallinity and purity of ZnO and smaller crystallite size in the range of 22.09 – 31.97 nm.Key words: X-ray diffraction, nanostructures, ZnO, sonication, Scherrer

scholarly journals Structural and Optical Changes of Undoped GaN Layers Grown via Radio-frequency Magnetron Sputtering Obtained from GaN Powders

2019 ◽  
Vol 4 (2) ◽  
pp. 59-63
Author(s):  
Erick Gastellóu ◽  
Crisoforo Morales ◽  
Godofredo García ◽  
Rafael García ◽  
Gustavo Alonso Hirata ◽  
...  
Keyword(s):  
Magnetron Sputtering ◽  
Radio Frequency ◽  
Crystal Size ◽  
Radio Frequency Magnetron ◽  
Radio Frequency Magnetron Sputtering ◽  
X Ray Diffraction ◽  
Homogeneous Surface ◽  
X Ray ◽  
Significant Difference ◽  
Diffraction Patterns

Undoped GaN layers were grown via radio-frequency magnetron sputtering, using a target manufactured with undoped GaN powders. Where the GaN powders were sintetized by nitridation of metallic gallium at 1000 °C in ammonia flow for two hours. X-ray diffraction patterns demonstrated that there are not a significant difference between the diffraction angles of the GaN powders and the GaN layers. The x-ray diffraction patterns for the GaN powders showed narrow peaks with a crystal size of 41 nm, while the GaN layers showed broad peaks with a crystal size of 7.7 nm. Scanning electron microscopy micrographs demonstrated the formation of crystals of irregular size with an average length of 1.56 μm for the GaN powders, while a homogeneous surface morphology with a thickness of 6.6 μm for the GaN layers was observed. Photoluminescence spectra showed a high emission at 3.49 eV (355.13 nm) for the GaN powders and an emission band energy located at 3.42 eV (361.54 nm) for the GaN layers, both emission bands were related to the band-to-band transition for the GaN. Raman spectra for the GaN powders showed the A1(TO), E1(TO), and E2(High) classical vibration modes. The GaN layers only showed the A1(TO) mode.

Structural and Photoluminescence Characteristics of Cu Doped CdS Nanoparticles

2018 ◽  
Vol 24 (8) ◽  
pp. 5657-5660
Author(s):  
K Raviteja ◽  
N Sreelekha ◽  
D. Amaranatha Reddy ◽  
R. P Vijayalakshmi ◽  
K Subramanyam
Keyword(s):  
Green Emission ◽  
Host Lattice ◽  
Emission Peak ◽  
Cds Nanoparticles ◽  
Stoichiometric Ratio ◽  
X Rays ◽  
X Ray Diffraction ◽  
X Ray ◽  
Green Emission Peak ◽  
Diffraction Patterns

EDTA surfactant assisted bare and Cu doped CdS nanoparticles were prepared by simple chemical coprecipitation method. As the prepared samples were characterized by energy dispersive analysis of X-rays (EDAX), X-ray diffraction patterns (XRD), transmission electron microscopy (TEM), Raman spectroscopy and photoluminescence spectroscopy (PL). Existence of Cu in host lattice with near stoichiometric ratio was corroborated by EDAX spectra. X-ray diffraction patterns revealed that cubic structure as that of CdS host lattice. TEM images suggested that spherical nature of nanoparticles with a size ranging from 4–6 nm. Room temperature photoluminescence (PL) spectra revealed that pristine host lattice nanoparticles demonstrate a strong green emission peak located at 525 nm as well as weak red emission shoulder situated at 598 nm. Auxiliary in Cu doped CdS samples, the luminescence intensity was gradually reduced as well as the green emission peak was shifted to red region (660 nm). With increase of Cu content in host matrix a red shift is found in the PL emission peak.

SYNTHESIS OF NANOCRYSTALLINE ANATASE TiO2 BY SOL–GEL METHOD

2006 ◽  
Vol 05 (02n03) ◽  
pp. 239-243 ◽  
Author(s):  
HUAMING YANG ◽  
RONGRONG SHI ◽  
KE ZHANG ◽  
YUEHUA HU ◽  
HUIHUI ZHANG ◽  
...  
Keyword(s):  
Crystal Size ◽  
Sol Gel ◽  
Atomic Ratio ◽  
Stoichiometric Ratio ◽  
Average Crystal Size ◽  
X Ray Diffraction ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method ◽  
Nanocrystalline Anatase Tio2

Synthesis of uniform nanocrystalline anatase TiO 2 by sol–gel method was investigated using different thermal analysis (DTA), thermogravimetric analysis (TGA), X-ray diffraction (XRD) and scanning electron microscope (SEM) techniques. Thermal treatment of the precursor at 350°C for 2 h in air results in the formation of nanocrystalline anatase TiO 2 with the average crystal size of 21.5 nm. Quantitative analysis through energy dispersive X-ray spectroscopy (EDS) indicated that the atomic ratio of Ti:O ≈ 1:1 is close to the stoichiometric ratio of TiO 2, leading to the evident fact that the prepared nanoparticles are indeed the TiO 2 material.

High Resolution Replication of Organoclay Surfaces

1982 ◽  
Vol 40 ◽  
pp. 576-577
Author(s):  
W. W. Barker ◽  
W. E. Rigsby ◽  
V. J. Hurst ◽  
W. J. Humphreys
Keyword(s):  
Clay Mineral ◽  
Organic Molecule ◽  
Organic Molecules ◽  
X Ray Diffraction ◽  
Xrd Pattern ◽  
X Ray ◽  
Naturally Occurring ◽  
Silicate Layers ◽  
Mineral Identification

Experimental clay mineral-organic molecule complexes long have been known and some of them have been extensively studied by X-ray diffraction methods. The organic molecules are adsorbed onto the surfaces of the clay minerals, or intercalated between the silicate layers. Natural organo-clays also are widely recognized but generally have not been well characterized. Widely used techniques for clay mineral identification involve treatment of the sample with H2 O2 or other oxidant to destroy any associated organics. This generally simplifies and intensifies the XRD pattern of the clay residue, but helps little with the characterization of the original organoclay. Adequate techniques for the direct observation of synthetic and naturally occurring organoclays are yet to be developed.

Evaluation of Freezing Methods by Low Temperature X-Ray Diffraction

1977 ◽  
Vol 35 ◽  
pp. 330-333
Author(s):  
T. Gulik-Krzywicki ◽  
M.J. Costello
Keyword(s):  
Biological Materials ◽  
Molecular Organization ◽  
X Ray Diffraction ◽  
Glass Capillary ◽  
X Ray ◽  
Rate Dependent ◽  
Before And After ◽  
Freeze Etching ◽  
Diffraction Patterns ◽  
Set Up

Freeze-etching electron microscopy is currently one of the best methods for studying molecular organization of biological materials. Its application, however, is still limited by our imprecise knowledge about the perturbations of the original organization which may occur during quenching and fracturing of the samples and during the replication of fractured surfaces. Although it is well known that the preservation of the molecular organization of biological materials is critically dependent on the rate of freezing of the samples, little information is presently available concerning the nature and the extent of freezing-rate dependent perturbations of the original organizations. In order to obtain this information, we have developed a method based on the comparison of x-ray diffraction patterns of samples before and after freezing, prior to fracturing and replication.Our experimental set-up is shown in Fig. 1. The sample to be quenched is placed on its holder which is then mounted on a small metal holder (O) fixed on a glass capillary (p), whose position is controlled by a micromanipulator.

Sign in / Sign up

Export Citation Format

Share Document