Influence of Cyclodextrin in the Synthesis of Magnetite

2009 ◽  
Vol 1243 ◽  
Author(s):  
L. A. Cobos Cruz ◽  
C. A. Martínez Perez ◽  
A Martínez Villafañe ◽  
J. A. Matutes Aquino ◽  
J. R. Farias Macilla ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Inorganic Material ◽  
Inorganic Nanoparticles ◽  
Spherical Particles ◽  
X Ray Diffraction ◽  
Guest Molecules ◽  
X Ray ◽  
Ft Ir ◽  
Scanning Electron ◽  
Made In

ABSTRACTCyclodextrin (CD) has been studied intensively due to its ability to form inclusion complexes with a variety of guest molecules in the solid state. A few studies have paid attention to the use of CD to facilitate the synthesis of inorganic nanoparticles. In this work the synthesis of magnetite (M) is made in the presence of CD. The particle size of the inorganic material is controlled by the presence of CD, in which spherical particles of few nanometers are grown. The synthesis of Fe3O4 (M) in the presence of α-cyclodextrin (α-CD) and β-cyclodextrin (βCD) is described. The formation of an M-CD complex is studied in both cases by Fourier transform infrared spectroscopy (FT-IR) in order to elucidate the chemical bonding of the complex. The morphology and size of the particles are determined by Field Emission Scanning Electron Microscopy (FESEM) and software. X-ray diffraction (XRD) is used to confirm the formation of magnetite.

scholarly journals A Novel Strong Cyan Luminescence Emission of Tb2O3 Particles

2021 ◽  
Author(s):  
Fatma Unal
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Ammonium Carbonate ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
Terbium Oxide ◽  
X Ray ◽  
Ft Ir ◽  
Pl Emission ◽  
Scanning Electron

Abstract Terbium oxide (Tb2O3) particles (NPs) were synthesized by precipitation method using ammonium carbonate as precipitation agent. Effects of precursor molarity (0.1, 0.15 and 0.2 M) on photoluminescence (PL) behaviour of the NPs were investigated. The presence of the Tb2O3 phase was confirmed by X-Ray Diffraction (XRD) and Fourier-transform infrared spectroscopy (FT-IR) analyses. Morphological investigations of the produced powders were made by Field Emission Gun-Scanning Electron Microscopy (FEG-SEM). It showed that the morphology of Tb2O3 particles transformed from the nanograin chain to bundles morphology of rod-like as the amount of precursor molarity increased. Emission spectrum were investigated by Photoluminescence (PL) Spectroscopy. All the Tb2O3 particles exhibited the strongest peak at 493 nm ascribed to 5D4-7F6 (magnetic dipole (MD), C2) transition. The increase in the number of C2 sites released from the MD transition with the increase of the precursor molarity caused a negative increase in the b* (yellowness/blueness of the emission) value in the CIE diagram, indicating that the colour shifted to the blue region. The Tb2O3 particles produced by the precipitation method exhibited novel strong cyan colour and the PL emission intensity increased with increasing molarity.

Electrochemical Synthesis and Photocatalytic Activity of Differently Shaped CuOx Particles

2017 ◽  
Vol 13 ◽  
pp. 330-333
Author(s):  
Anna Ulyankina ◽  
Igor Leontyev ◽  
Nina Smirnova
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Activity ◽  
Electrochemical Method ◽  
Spherical Particles ◽  
Photocatalytic Efficiency ◽  
X Ray Diffraction ◽  
X Ray ◽  
Polyhedral Particles ◽  
Copper Electrodes ◽  
Scanning Electron

CuOx powders with diff erently shaped particles were firstly prepared via an electrochemical method by oxidation and dispersion of copper electrodes in an electrolyte solution under pulse alternating current (PAC). By means of X-ray diffraction (XRD) and scanning electron microscopy (SEM) the current density is found to have an influence on the morphology and composition of CuOx particles. Photocatalytic efficiency of CuOx towards methyl orange (MO) degradation under visible light was investigated. The prepared polyhedral particles show the best photocatalytic activity of 81 % towards MO comparing to octahedral and spherical particles with 70 and 61 %, respectively.

The Characterization of Bovine Bone-Derived Hydroxyapatite Isolated Using Novel Non-Hazardous Method

2020 ◽  
Vol 45 ◽  
pp. 49-56
Author(s):  
Aniek Setiya Budiatin ◽  
Samirah ◽  
Maria Apriliani Gani ◽  
Wenny Putri Nilamsari ◽  
Chrismawan Ardianto ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Extraction Method ◽  
Bovine Bone ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ft Ir ◽  
Novel Method ◽  
Scanning Electron

Bovine bone is a considerable source for the production of hydroxyapatite. The recent study reported a novel method to extract hydroxyapatite from bovine bone without producing hazardous residue. The bovine bones were cut and boiled in the opened chamber followed by boiling in pressurized tank. The bones were then soaked into 95% ethanol. Calcination was then conducted in 800°C, 900°C and 1,000°C, for 2 hours. The result was then grinded and sieved. The powder then was characterized using Fourier transform infrared (FT-IR), Scanning electron microscopy (SEM) and X-ray diffraction analysis (XRD) to measure the purity of hydroxyapatite. It is concluded that the hydroxyapatite derived from this process showed 100% purity, resulting 35.34 ± 0.39% w/w from the wet bone weight and 72.3% w/w from the dried weight. The present extraction method has been proven to yield high amount of pure hydroxyapatite as well as reducing the use of hazardous reagent.

Synthesis of Triethynylborazine-Polyhydromethylsiloxane Copolymers and its Ceramization

2013 ◽  
Vol 774-776 ◽  
pp. 629-633
Author(s):  
Ji Feng Jiang ◽  
Kang Kang Guo ◽  
Ya Ping Zhu ◽  
Fan Wang ◽  
Hui Min Qi
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Nuclear Magnetic Resonance ◽  
Fourier Transform ◽  
Thermogravimetric Analysis ◽  
X Ray Diffraction ◽  
Hydrosilylation Reaction ◽  
X Ray ◽  
Ft Ir ◽  
Scanning Electron

Triethynylborazine-polyhydromethylsiloxane copolymers (TEB-PHMSs) were prepared through hydrosilylation reaction between -C≡CH attached to boron and ≡Si-H. The structures of TEB-PHMSs were characterized by Fourier transform Infrared (FT-IR) and Nuclear Magnetic Resonance (NMR) spectroscopy. Their cure behavior were examined by Differential Scanning Calorimeter (DSC) and FT-IR, and then thermostability and ceramization of cured TEB-PHMS were investigated by Thermogravimetric analysis (TGA), pyrolysis-GC-MS, X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). The results indicated that TEB-PHMSs could be cured and converted into an outstanding thermostable SiBCN ceramics.

Synthesis, Characterization and Magnetism of Nanosized Copper Ferrite

2008 ◽  
Vol 368-372 ◽  
pp. 604-606 ◽  
Author(s):  
Wei Zhong Lv ◽  
Zhong Kuang Luo ◽  
Bo Liu ◽  
Xiang Zhong Ren ◽  
Hong Hua Cai ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Thermal Analysis ◽  
Copper Ferrite ◽  
Sonochemical Method ◽  
Thermal Gravimetric ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Ft Ir ◽  
Scanning Electron

Copper ferrite powders were successfully synthesized by sonochemical method. The resultant powders were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), FT-IR, differential thermal analysis-thermal gravimetric (DTA-TG), differential scanning calorimetry (DSC) and VSM. The particle saturation magnetization (Ms) is 66 emu/g and an intrinsic coercive force (iHc) is 2100 Oe when the precursor calcined at 950 °C for 15 h.

scholarly journals FT-IR φασματοσκοπική μελέτη ασθενειών των οστών

2016 ◽  
Author(s):  
Στυλιανός Κυριαζής
Keyword(s):  
Electron Microscopy ◽  
Reactive Oxygen Species ◽  
Scanning Electron Microscopy ◽  
Oxygen Species ◽  
X Ray Diffraction ◽  
Cross Link ◽  
X Ray ◽  
Ft Ir ◽  
Ros Reactive Oxygen Species ◽  
Scanning Electron

Οι παθήσεις των οστών και η θεραπεία τους σχετίζονται άμεσα με την γνώση των βλαβών που προκαλούν οι ασθένειες σε μοριακό επίπεδο των βιολογικών μορίων, ιστών και υγρών του σώματος. Μέχρι σήμερα, πολλές από τις ασθένειες δεν μπορούν να αντιμετωπιστούν μη επεμβατικά, επειδή δεν έχουν παρασκευασθεί φάρμακα τα οποία θα μπορούσαν να επιδιορθώσουν τις βλάβες. Δυστυχώς, μέχρι σήμερα, η συνήθης αντιμετώπιση των περισσότερων ασθενειών είναι η χειρουργική αφαίρεση του τμήματος του οστού που έχει φθαρεί. Η γνώση επομένως των βλαβών οι οποίες προκαλούνται από τις ασθένειες θα μπορούσε ενδεχομένως να οδηγήσει στην ανάπτυξη φαρμάκων και την εξέλιξη της μη επεμβατικής αντιμετώπισης αυτών των ασθενειών .Στην παρούσα μελέτη χρησιμοποιήθηκαν μη καταστρεπτικές μέθοδοι, όπως η υπέρυθρη φασματοσκοπία με μετασχηματισμό Fourier (Fourier Transform Infrared, FT-IR) και ηλεκτρονιακό μικροσκόπιο σάρωσης (Scanning Electron Microscopy, SEM) και περίθλαση ακτίνων Χ (XRD, X-Ray Diffraction).Για την μελέτη λήφθηκαν δείγματα φλοιώδους και σπογγώδους οστού, καθώς και χόνδρου οστού από 42 ασθενείς ηλικίας 31 έως 87 ετών, οι οποίοι υποβλήθηκαν σε χειρουργική αντιμετώπιση. Από αυτά 15 προήλθαν από ασθενείς με αναπτυξιακή δυσπλασία του ισχίου, 1 από αγκυλοποιητική αρθρίτιδα του ισχίου, 4 από έκτοπη οστεοποίηση του ισχίου, 3 λόγω οστεονέκρωσης της μηριαίας κεφαλής, 1 από ρευματοειδή αρθρίτιδα του γόνατος, 2 έπειτα από χαλάρωση ολικής αρθροπλαστικής γόνατος, 4 έπειτα από χαλάρωση ολικής αρθροπλαστικής ισχίου και 2 από ψωριασική αρθρίτιδα (ισχίου και γόνατος) και 10 καρκινικά. Τα δείγματα δεν υπέστησαν καμία επεξεργασία πέραν της αφαίρεσης των προσμίξεων αίματος και λιπαρών συστατικών του εξωτερικού περιβάλλοντος του οστού. Τα υπέρυθρα φάσματα έδειξαν σημαντικές διαφορές μεταξύ των υγιών οστών και των οστών τα οποία προήλθαν από τα δείγματα των ασθενών. Οι μεταβολές ήταν συνάρτηση της ασθένειας αλλά και των συστατικών του εκάστοτε οστού. Γενικά διαπιστώθηκε ότι σε κάθε περίπτωση το οξειδωτικό στρες συμμετέχει σε κάποιο από τα στάδια της ανάπτυξης της ασθένειας. Κατά το οξειδωτικό στρες παράγονται ελεύθερες ρίζες (ROS, reactive oxygen species) οι οποίες οδηγούν σε υπεροξείδωση των λιπιδίων και φωσφολιπιδίων των μεμβρανών των κυττάρων και κατά συνέπεια στην καταστροφή των κυττάρων. Από τις μειώσεις των εντάσεων και τις μετατοπίσεις των απορροφήσεων τάσης των ομάδων νΟΗ και νΝΗ στην περιοχή του φάσματος από 4000-3000 cm-1 φαίνεται ότι ο υδροξυαπατίτης χάνει τις ομάδες -ΟΗ, ενώ οι δεσμοί υδρογόνου οι οποίοι συγκρατούν την α-έλικα των κολλαγονούχων πρωτεϊνών μεταβάλλουν την έντασή τους. Αυτό επιβεβαιώνεται από τις μετατοπίσεις των ταινιών των Amide I και Amide II των πρωτεϊνών προς μικρότερες συχνότητες στην περιοχή 1700-1500 cm-1, ως αποτέλεσμα της καταστροφής της α-έλικας. Το φαινόμενο αυτό είναι περισσότερο έντονο στην περίπτωση των χόνδρων. Η ταινία περίπου στα 3080 cm-1, η οποία συνδέεται με την ολεφινική ομάδα (v=CH) επιβεβαιώνει την επίδραση των ελευθέρων ριζών στα στάδια της ασθένειας. Η αύξηση των εντάσεων των ταινιών των μεθυλ (vCH3) και μεθυλενομάδων (vCH2) στην περιοχή 3000-2850 cm-1 συνδέεται με την αύξηση του λιπόφιλου περιβάλλοντος, ως αποτέλεσμα της επίδρασης του οξειδωτικού στρες και τον σχηματισμό αμυλοειδών πρωτεϊνών. Η ταινία στα 1743 cm-1 η οποία αποδίδεται σε σχηματισμό αλδεϋδικών ομάδων συνδέεται με το οξειδωτικό στρες και επομένως με την φλεγμονή. Σε ασθενείς οι οποίοι εμφάνιζαν χρόνια φλεγμονή η ένταση της ταινίας είναι αρκετά υψηλή. Τα υπέρυθρα φάσματα έδειξαν την καταστροφή του υδροξυαπατίτη των οστών και την μετατροπή του σε άλατα του φωσφορικού ασβεστίου, προσδίδοντας επομένως μεγαλύτερη σκληρότητα και ευθραυστότητα στο οστό. Η καταστροφή του βιολογικού υδροξυαπατίτη επιβεβαιώθηκε με XRD ανάλυση.Οι SEM αναλύσεις έδειξαν την καταστροφή των πρωτεϊνών του οστού. Από την ανάλυση της εικόνας φάνηκαν οι θέσεις διασταυρούμενων (cross-link) και διακλαδούμενων (branch-link) πολυμερισμών. Οι θέσεις αυτές αποτελούν δραστικά σημεία σχηματισμού φωσφορικών αλάτων, τα οποία μειώνουν την αντοχή των οστών. Επίσης επιβεβαιώνουν την επίδραση των ελευθέρων ριζών.Η έκτοπη οστεοποίηση φαίνεται να μην είναι αποτέλεσμα της δράσης των οστεοβλαστών, αλλά της αδυναμίας λειτουργίας του ATP στον φυσιολογικό κύκλο λόγω ισχαιμικών επεισοδίων που επικρατούν στην περιοχή ανάπτυξης του οστού. Αυτό επιβεβαιώθηκε από την σύγκριση των φασμάτων έκτοπου οστού και επασβεστωμένης αορτικής βαλβίδας. Τέλος, στον σχηματισμό των αμυλοειδών πρωτεϊνών αποδίδουμε την αντίσταση στην θεραπευτική αγωγή και ακτινοθεραπεία των οστών.

Nanostructured CaWO4, CaWO4:Eu3+ and CaWO4:Tb3+ Particles: Sonochemical Synthesis and Luminescent Properties

2008 ◽  
Vol 8 (3) ◽  
pp. 1183-1190 ◽  
Author(s):  
Chunxia Li ◽  
Cuikun Lin ◽  
Xiaoming Liu ◽  
Jun Lin
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Field Emission ◽  
Spherical Particles ◽  
X Ray Diffraction ◽  
Blue Emission Band ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Electron

Nanostructured CaWO4, CaWO4:Eu3+, and CaWO4:Tb3+ phosphor particles were synthesized via a facile sonochemical route. X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, transmission electron microscopy, photoluminescence, low voltage cathodoluminescence spectra, and photoluminescence lifetimes were used to characterize the as-obtained samples. The X-ray diffraction results indicate that the samples are well crystallized with the scheelite structure of CaWO4. The transmission electron microscopy and field emission scanning electron microscopy images illustrate that the powders consist of spherical particles with sizes from 120 to 160 nm, which are the aggregates of even smaller nanoparticles ranging from 10 to 20 nm. Under UV light or electron beam excitation, the CaWO4 powder exhibited a blue emission band with a maximum at 430 nm originating from the WO2−4 groups, while the CaWO4:Eu3+ powder showed red emission dominated by 613 nm ascribed to the 5D0 → 7F2 of Eu3+, and the CaWO4:Tb3+ powders showed emission at 544 nm, ascribed to the 5D4 → 7F5 transition of Tb3+. The PL excitation and emission spectra suggest that the energy is transferred from WO2−4 to Eu3+CaWO4:Eu3+ and to Tb3+ in CaWO4:Tb3+. Moreover, the energy transfer from WO2−4 to Tb3+ in CaWO4:Tb3+ is more efficient than that from WO2−4 to Eu3+ in CaWO4:Eu3+. This novel and efficient pathway could open new opportunities for further investigating the novel properties of tungstate materials.

Preparation of Nanosized Barium Ferrite Spinel by a Sonochemical Method

2008 ◽  
Vol 368-372 ◽  
pp. 607-609
Author(s):  
Bo Liu ◽  
Wei Zhong Lv ◽  
Zhong Kuang Luo ◽  
Xiang Zhong Ren ◽  
Hong Hua Cai ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Barium Ferrite ◽  
Sonochemical Method ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Ultrasound Radiation ◽  
Ft Ir ◽  
Scanning Electron ◽  
Ferrite Spinel

Nanosized barium ferrite spinel particles were prepared with the aid of ultrasound radiation by a precursor approach. A precursor was got by sonicating an aqueous solution of BaCl2, Fe (NO3)3·9H2O and urea firstly. Nanosized BaFe2O4 particles with a size of ca.40nm were prepared after the precursor was heated at 950 °C for 15 h. The nanosized barium ferrite particles and the precursor were characterized by powder X-ray diffraction, scanning electron microscopy, FT-IR and differential scanning calorimetry.

Study of the Reproducibility of Ni-Zn Nanoferrite Obtained by Combustion Reaction

2014 ◽  
Vol 775-776 ◽  
pp. 415-420 ◽  
Author(s):  
Débora Albuquerque Vieira ◽  
Verônica Cristina Souza Diniz ◽  
Daniel R. Cornejo ◽  
Ana Cristina Figueiredo de Melo Costa ◽  
Ruth Herta Goldsmith Aliaga Kiminami
Keyword(s):  
Electron Microscopy ◽  
Combustion Synthesis ◽  
Soft Magnetic Materials ◽  
Spherical Particles ◽  
Magnetic Characteristics ◽  
X Ray Diffraction ◽  
Soft Magnetic ◽  
X Ray ◽  
Crystallite Sizes ◽  
Scanning Electron

This work involved a study of the reproducibility of the process of combustion synthesis to produce Ni-Zn ferrites. The structural, morphological and magnetic characteristics of the samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and magnetometry using an alternating gradient magnetometer (AGM). The XRD diffractograms of the samples indicated that they are monophasic, crystalline, with crystallite sizes ranging from 21 to 38 nm, and have a homogeneous morphology consisting of agglomerates of spherical particles. The samples behaved as soft magnetic materials, with magnetization levels ranging from 37 to 47 emug-1. The combustion synthesis was found to be efficient in producing Ni-Zn nanoferrites, yielding reproducible results.

From Layered Ni(OH)2 Thin Films to Ni(so4)0.3(OH)1.4 Nanobelts through so42- Inserting in Colloid-Based Route

2011 ◽  
Vol 295-297 ◽  
pp. 1548-1553
Author(s):  
Zhi Yong Jia
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Large Scale ◽  
Ph Value ◽  
Shape Evolution ◽  
X Ray Diffraction ◽  
Weak Base ◽  
X Ray ◽  
Ft Ir ◽  
Scanning Electron

The single-crystalline nanobelts of monoclinic Ni(SO4)0.3(OH)1.4have been synthesized on a large scale through a convenient, low-temperature hydrothermal method. The influences of reaction time, pH value, concentration of ammonia on the phase and shape evolution of nanobelts were systematically investigated. It was found that the initial layered Ni(OH)2 thin films as intermediates could be split and converted into the monoclinic Ni(SO4)0.3(OH)1.4nanobelts through SO42-ions inserting process. The formation mechanism of nanobelts involved in the inserting process and the corresponding drive force have been investigated in detail by means of X-ray diffraction (XRD), and scanning electron microscopy (SEM), FT-IR spectra and pH value analyses. In addition to, we have also found that the ammonia molecules acted as both weak base and ligand agent was crucial to the controlling nucleation and inserting process in the formation process of nanobelts.

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