Preparation and Photoluminescent Properties of Polystyrene Encapsulated SrAl2O4:Eu2+,Dy3+ Nanocrystals

2013 ◽  
Vol 538 ◽  
pp. 197-200 ◽  
Author(s):  
Bao Gai Zhai ◽  
Yuan Ming Huang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Optical Properties ◽  
Phase Morphology ◽  
X Ray ◽  
Weight Percentage ◽  
Deep Blue ◽  
The Matrix ◽  
Pl Spectrum ◽  
Scanning Electron

Polystyrene encapsulated phosphors SrAl2O4:Eu2+,Dy3+ were prepared by dispersing the phosphors into the matrix of polystyrene. The phase, morphology and optical properties of the polystyrene encapsulated phosphors were characterized with X-ray diffractometry, scanning electron microscopy and photoluminescence (PL) spectroscopy, respectively. It has been observed that both the PL spectrum and the luminescent color of the polystyrene encapsulated phosphors can be dramatically modified although the phosphorescence of the polystyrene encapsulated phosphors is not affected. Tunable photoluminescent colors from green to deep-blue are expected for the polystyrene encapsulated phosphors by the control of the weight percentage of the phosphors in the composites.

scholarly journals Structural and optical properties of SnO2–Al2O3 nanocomposite synthesized via sol-gel route

2015 ◽  
Vol 33 (4) ◽  
pp. 714-718 ◽  
Author(s):  
Neeraj K. Mishra ◽  
Chaitnaya Kumar ◽  
Amit Kumar ◽  
Manish Kumar ◽  
Pratibha Chaudhary ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Optical Properties ◽  
Sol Gel ◽  
Physical Interaction ◽  
X Ray Diffraction ◽  
Structural And Optical Properties ◽  
X Ray ◽  
Sensing Applications ◽  
Scanning Electron

AbstractA nanocomposite of 0.5SnO2–0.5Al2O3 has been synthesized using a sol-gel route. Structural and optical properties of the nanocomposite have been discussed in detail. Powder X-ray diffraction and scanning electron microscopy with energy-dispersive X-ray diffraction spectroscopy confirm the phase purity and the particle size of the 0.5SnO2–0.5Al2O3 nanocomposite (13 to 15 nm). The scanning electron microscopy also confirms the porosity in the sample, useful in sensing applications. The FT-IR analysis confirms the presence of physical interaction between SnO2 and Al2O3 due to the slight shifting and broadening of characteristic bands. The UV-Vis analysis confirms the semiconducting nature because of direct transition of electrons into the 0.5SnO2–0.5Al2O3 nanocomposites.

Characteristics of Ni–Cr–Fe laser clad layers on EA4T steel

2017 ◽  
Vol 31 (16-19) ◽  
pp. 1744031
Author(s):  
Wenjing Chen ◽  
Hui Chen ◽  
Yongjing Wang ◽  
Congchen Li ◽  
Xiaoli Wang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cladding Layer ◽  
Metallurgical Bonding ◽  
The Matrix ◽  
Feeding Speed ◽  
Upper Bainite ◽  
Scanning Electron

The Ni–Cr–Fe metal powder was deposited on EA4T steel by laser cladding technology. The microstructure and chemical composition of the cladding layer were analyzed by optical microscopy (OM), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The bonding ability between the cladding layer and the matrix was measured. The results showed that the bonding between the cladding layer and the EA4T steel was metallurgical bonding. The microstructure of cladding layer was composed of planar crystals, columnar crystals and dendrite, which consisted of Cr2Ni3, [Formula: see text] phase, M[Formula: see text]C6 and Ni3B phases. When the powder feeding speed reached 4 g/min, the upper bainite occurred in the heat affected zone (HAZ). Moreover, the tensile strength of the joint increased, while the yield strength and the ductility decreased.

scholarly journals The Influence of A Mo Addition on the Interfacial Morphologies and Corrosion Resistances of Novel Fe-Cr-B Alloys Immersed in Molten Aluminum

Materials ◽  
2019 ◽  
Vol 12 (2) ◽  
pp. 256 ◽  
Author(s):  
Zicheng Ling ◽  
Weiping Chen ◽  
Weiye Xu ◽  
Xianman Zhang ◽  
Tiwen Lu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Electron Probe ◽  
Molten Aluminum ◽  
Dendritic Structure ◽  
H13 Steel ◽  
X Ray ◽  
Transmission Electron ◽  
The Matrix ◽  
Scanning Electron

The influence of a Mo addition on the interfacial morphologies and corrosion resistances of novel Fe-Cr-B alloys in molten aluminum at 750 °C was systematically investigated using scanning electron microscopy, X-ray diffractometer, electron probe microanalysis, and transmission electron microscopy. The results indicated that Mo could not only strengthen the matrix but also facilitate the formation of borides. Furthermore, the microstructures of Mo-rich M2B boride changed from a local eutectic net-like structure to a typical coarse dendritic structure and a blocky hypereutectic structure with increasing Mo addition. This was true of the blocky Mo-rich M2B boride, rod-like Cr-rich M2B boride and the corrosion products, which had a synergistic effect on retarding of the diffusion of molten aluminum. Notably, the corrosion resistance of the Fe-Cr-B-Mo alloy, with an 8.3 wt.% Mo addition, was 3.8 times higher than that of H13 steel.

Sintering characteristics of Y–Ba–Cu–oxide–Agx superconductors

1999 ◽  
Vol 14 (11) ◽  
pp. 4148-4156 ◽  
Author(s):  
L. C. Pathak ◽  
S. K. Mishra ◽  
D. Bhattacharya ◽  
K. L. Chopra
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Weak Link ◽  
Sintering Atmosphere ◽  
X Ray ◽  
The Matrix ◽  
Apparent Activation Energies ◽  
Sintering Characteristics ◽  
Powder Compacts ◽  
Scanning Electron

The sintering characteristics of Y–Ba–Cu–oxide (YBCO)–Agx (x = 0 to 1.2) using thermomechanical analyzer were systematically investigated to understand the sintering mechanism of the metal superconductor composites. The addition of Ag was observed to lower the sintering temperatures, and the apparent densities of the sintered compacts increased with x from 0 to 0.6. A further increase of x above 0.6 decreased the apparent densities of the sintered compacts. The presence of Ag globules in the YBCO–Ag compacts was observed by scanning electron microscopy and energy dispersive x-ray spectroscopy. The apparent activation energies for sintering of the powder compacts were estimated and observed to vary between 900 to 2000 kJ/mol. The formation of AgOx by absorbing oxygen from YBCO and sintering atmosphere possibly controls the sintering and superconducting behavior. Incorporation of Ag into the matrix modifies the weak-link characteristics from superconductor–insulator– normal–superconductor (S–I–N–S) to superconductor–normal–superconductor (S–N–S) type.

Hydrothermal Synthesis of SrSO4:Eu2+ Microcrystals with Different Morphologies and its Luminescence Properties

2014 ◽  
Vol 633-634 ◽  
pp. 341-344 ◽  
Author(s):  
Jia Yue Sun ◽  
Qiu Mei Di ◽  
Liu Han ◽  
Qi Guang Xu ◽  
Chen Liang Ma
Keyword(s):  
Electron Microscopy ◽  
Aqueous Solution ◽  
Scanning Electron Microscopy ◽  
Optical Properties ◽  
Hydrothermal Synthesis ◽  
Emission Spectroscopy ◽  
Electron Trapping ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scanning Electron

Electron trapping materials SrSO4:Eu2+were prepared by hydrothermal method from fatty alcohol polyoxyethylene (3) ether (AEO-3) aqueous solution at 200 °C for 20 h. The phase structure, microstructure and optical properties were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM) and excitation-emission spectroscopy (PL-PLE), respectively.

scholarly journals Magnetic nanowires (Fe, Fe-Co, Fe-Ni) – magnetic moment reorientation in respect of wires composition

Nukleonika ◽  
2015 ◽  
Vol 60 (1) ◽  
pp. 63-67 ◽  
Author(s):  
Beata Kalska-Szostko ◽  
Urszula Wykowska ◽  
Dariusz Satuła
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Strong Dependence ◽  
Magnetic Nanowires ◽  
Deposition Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ni Alloy ◽  
The Matrix ◽  
Scanning Electron

Abstract Magnetic nanowires of Fe, Fe-Co, and Fe-Ni alloy and layered structure were prepared by electrochemical alternating current (AC) deposition method. The morphology of the nanowires in and without the matrix was studied by energy dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), and X-ray diffraction (XRD), respectively. The wires either show strong dependence on the combination of elements deposition (alloy or layered) or chemical composition (Co or Ni). The magnetic properties of the nanostructures were determined on the basis of Mössbauer spectroscopy (MS).

Effect of Ca on Microstructure and Properties of Mg-Al-Si Alloys

2011 ◽  
Vol 194-196 ◽  
pp. 1369-1373 ◽  
Author(s):  
Chun Xiang Xu ◽  
Hui Ju ◽  
Yang Zhou
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Scanning Electron Microscopy ◽  
Chinese Script ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ca Addition ◽  
The Matrix ◽  
Morphology Modification ◽  
Scanning Electron

Effect of Ca addition on the morphology modification in Mg-7Al-0.8Zn-0.2Mn-1Si (AS71) alloys has been investigated using X-ray diffraction (XRD), optical microscopy (OM), and scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and various testing machines. The results show that when adding 0.1 wt% Ca, a small fraction of Mg2Si change from Chinese script type to polygonal type; with the Ca addition up to 0.3 wt%, edges and angles of polygonal type Mg2Si phase are changed; further increase in Ca addition, the morphology of Mg2Si is changed to strip-like or spot-like one. Meanwhile, the addition of Ca results in the morphology of β- Mg17Al12 phase changing from discontinuous net-like to dispersive island-like. Ca exists as solid-soluting atomic in the matrix with small Ca addition while in the form of CaSi2 with large Ca addition. Optimal mechanical properties can be achieved when Ca addition is 0.3 wt%.

Soft-Template Synthesis of Single-Crystalline CdS Dendrites

2006 ◽  
Vol 6 (1) ◽  
pp. 162-167 ◽  
Author(s):  
Haixia Niu ◽  
Qing Yang ◽  
Kaibin Tang ◽  
Yi Xie ◽  
Yongchun Zhu
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Optical Properties ◽  
Soft Template ◽  
X Ray Diffraction ◽  
Single Crystalline ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Electron

The single-crystalline CdS dendrites have been fabricated from the reaction of CdCl2 and thiourea at 180 °C, in which glycine was employed as a soft template. The obtained products were explored by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and selected area electronic diffraction. The optical properties of CdS dendrites have been investigated by ultraviolet and visible light (UV-vis) and photoluminescence techniques. The investigations indicated that the dendrites were grown due to the anisotropic properties enhanced by the use of Glycine in the route.

scholarly journals Study of Structural and Optical Properties of Zinc Oxide Rods Grown on Glasses by Chemical Spray Pyrolysis

2012 ◽  
Vol 2012 ◽  
pp. 1-5 ◽  
Author(s):  
Erdal Sonmez ◽  
Serdar Aydin ◽  
Mehmet Yilmaz ◽  
Mustafa Tolga Yurtcan ◽  
Tevhit Karacali ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Atomic Force Microscopy ◽  
Optical Properties ◽  
Spray Pyrolysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
Scanning Electron

We have investigated morphological and optical properties of zinc oxide rods. Highly structured ZnO layers comprising with well-shaped hexagonal rods were prepared by spray pyrolysis deposition of zinc chloride aqueous solutions at ~550∘C. The rods were characterized by X-ray diffraction, scanning electron microscopy, atomic force microscopy, photoluminescence, and ultraviolet and visible absorption spectroscopy measurements. The deposition of the 0.1 mol/L solution at ~550∘C resulted in crystals with a diameter of 400–1000 nm and length of 500–2000 nm. Sharp near-band edge emission peaks, centered at 3844 and 3680 Å, dominated the PL spectra of ZnO at 300 K and 6.2 K, respectively. In addition to this, absorption coefficient was determined by absorption measurement. X-ray diffraction, scanning electron microscopy and atomic force microscopy, results suggest that ZnO rods, prepared by spray pyrolysis, have high crystalline quality. This is desirable in nanotechnology applications.

scholarly journals Structure Analysis and Properties of Unleaded Brasses

2015 ◽  
Vol 60 (1) ◽  
pp. 323-328 ◽  
Author(s):  
S. Rzadkosz ◽  
J. Kozana ◽  
A. Garbacz-Klempka ◽  
M. Piękoś
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Scanning Electron Microscopy ◽  
Light Microscopy ◽  
Structure Analysis ◽  
Structure And Properties ◽  
X Ray ◽  
Ecological Characteristics ◽  
The Matrix ◽  
Scanning Electron

Abstract The analysis of brasses regarding their microstructure, mechanical properties and ecological characteristics has been presented. The influence of characteristic alloying elements contained in the brasses and the possibilities of replacing them with other elements have been assessed. The paper contains the results of studies on the influence of chosen additional elements shaping the structure and properties of unleaded alloys based on Cu-Zn system as the matrix. The research aimed at determining the mechanism and the intensity of influence of such additives as tellurium and bismuth. The microstructures were investigated with the help of light microscopy and scanning electron microscopy with X-ray microanalysis (SEM-EDS) for determining significant changes of the properties.

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