scholarly journals DNA-modified silicon nanocrystals studied by X-ray luminescence and X-ray absorption spectroscopies: Observation of a strong infra-red luminescence band

2012 ◽  
Vol 111 (5) ◽  
pp. 054311 ◽  
Author(s):  
P. R. Coxon ◽  
M. Newman ◽  
M. R. C. Hunt ◽  
N. O’Farrell ◽  
B. R. Horrocks ◽  
...  
Keyword(s):  
Silicon Nanocrystals ◽  
Luminescence Band ◽  
X Ray ◽  
Infra Red ◽  
Red Luminescence ◽  
X Ray Absorption

X-ray Absorption Spectroscopy of Functionalized Silicon Nanocrystals

2010 ◽  
Vol 114 (51) ◽  
pp. 22519-22525 ◽  
Author(s):  
Joel A. Kelly ◽  
Eric J. Henderson ◽  
Rhett J. Clark ◽  
Colin M. Hessel ◽  
Ronald G. Cavell ◽  
...  
Keyword(s):  
Absorption Spectroscopy ◽  
Silicon Nanocrystals ◽  
X Ray ◽  
X Ray Absorption

Red-luminescence band: A tool for the quality assessment of germanium and silicon nanocrystals

2017 ◽  
Vol 419 ◽  
pp. 476-483 ◽  
Author(s):  
I. Fraj ◽  
L. Favre ◽  
T. David ◽  
M. Abbarchi ◽  
K. Liu ◽  
...  
Keyword(s):  
Quality Assessment ◽  
Silicon Nanocrystals ◽  
Luminescence Band ◽  
Red Luminescence

The origin of luminescence from di[4-(4-diphenylaminophenyl)phenyl]sulfone (DAPSF), a blue light emitter: an X-ray excited optical luminescence (XEOL) and X-ray absorption near edge structure (XANES) study

2016 ◽  
Vol 18 (9) ◽  
pp. 6406-6410 ◽  
Author(s):  
Duo Zhang ◽  
Hui Zhang ◽  
Xiaohong Zhang ◽  
Tsun-Kong Sham ◽  
Yongfeng Hu ◽  
...  
Keyword(s):  
Blue Light ◽  
Luminescence Band ◽  
Functional Group ◽  
Edge Structure ◽  
X Ray ◽  
Light Emitter ◽  
Phenyl Sulfone ◽  
Optical Luminescence ◽  
Blue Luminescence Band ◽  
X Ray Absorption

The blue luminescence band of DAPSF is primarily associated with the sulfur functional group.

X-ray absorption near-edge structure anomalous behaviour in structures with buried layers containing silicon nanocrystals

2013 ◽  
Vol 21 (1) ◽  
pp. 209-214 ◽  
Author(s):  
V. A. Terekhov ◽  
D. I. Tetelbaum ◽  
D. E. Spirin ◽  
K. N. Pankov ◽  
A. N. Mikhailov ◽  
...  
Keyword(s):  
Silicon Carbide ◽  
Absorption Edge ◽  
Energy Region ◽  
Silicon Nanocrystals ◽  
Silicon Oxide ◽  
Abnormal Behaviour ◽  
Edge Structure ◽  
X Ray ◽  
Absorption Edge Energy ◽  
X Ray Absorption

Substructure and phase composition of silicon suboxide films containing silicon nanocrystals and implanted with carbon have been investigated by means of the X-ray absorption near-edge structure technique with the use of synchrotron radiation. It is shown that formation of silicon nanocrystals in the films' depth (more than 60 nm) and their following transformation into silicon carbide nanocrystals leads to abnormal behaviour of the X-ray absorption spectra in the elementary silicon absorption-edge energy region (100–104 eV) or in the silicon oxide absorption-edge energy region (104–110 eV). This abnormal behaviour is connected to X-ray elastic backscattering on silicon or silicon carbide nanocrystals located in the silicon oxide films depth.

X-ray absorption study of light emitting silicon nanocrystals

2003 ◽  
Vol 16 (3-4) ◽  
pp. 321-325 ◽  
Author(s):  
N. Daldosso ◽  
G. Dalba ◽  
R. Grisenti ◽  
L. Dal Negro ◽  
L. Pavesi ◽  
...  
Keyword(s):  
Silicon Nanocrystals ◽  
Absorption Study ◽  
Light Emitting ◽  
X Ray ◽  
X Ray Absorption

Silicon 1s near edge X-ray absorption fine structure spectroscopy of functionalized silicon nanocrystals

2016 ◽  
Vol 145 (15) ◽  
pp. 154703 ◽  
Author(s):  
A. Ritchie ◽  
W. Cao ◽  
M. Dasog ◽  
T. K. Purkait ◽  
C. Senger ◽  
...  
Keyword(s):  
Fine Structure ◽  
Silicon Nanocrystals ◽  
X Ray ◽  
Absorption Fine ◽  
X Ray Absorption

Electron Microscopy of Human Gallstones

1971 ◽  
Vol 29 ◽  
pp. 296-297
Author(s):  
C. Wolpers ◽  
R. Blaschke
Keyword(s):  
Electron Microscopy ◽  
Room Temperature ◽  
Bile Pigment ◽  
X Ray Diffraction ◽  
Triclinic Crystal System ◽  
X Ray ◽  
Follow Up Study ◽  
Infra Red ◽  
Main Components

Scanning microscopy was used to study the surface of human gallstones and the surface of fractures. The specimens were obtained by operation, washed with water, dried at room temperature and shadowcasted with carbon and aluminum. Most of the specimens belong to patients from a series of X-ray follow-up study, examined during the last twenty years. So it was possible to evaluate approximately the age of these gallstones and to get information on the intensity of growing and solving.Cholesterol, a group of bile pigment substances and different salts of calcium, are the main components of human gallstones. By X-ray diffraction technique, infra-red spectroscopy and by chemical analysis it was demonstrated that all three components can be found in any gallstone. In the presence of water cholesterol crystallizes in pane-like plates of the triclinic crystal system.

X-ray microanalysis of thin specimens in the transmission electron microscope at voltages up to 1000 Kv.

1978 ◽  
Vol 36 (1) ◽  
pp. 540-541
Author(s):  
G. Cliff ◽  
M.J. Nasir ◽  
G.W. Lorimer ◽  
N. Ridley
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Weight Fraction ◽  
Present Series ◽  
Constant Independent ◽  
X Ray ◽  
Transmission Electron ◽  
Series Of Experiments ◽  
Image Position ◽  
X Ray Absorption

In a specimen which is transmission thin to 100 kV electrons - a sample in which X-ray absorption is so insignificant that it can be neglected and where fluorescence effects can generally be ignored (1,2) - a ratio of characteristic X-ray intensities, I1/I2 can be converted into a weight fraction ratio, C1/C2, using the equationwhere k12 is, at a given voltage, a constant independent of composition or thickness, k12 values can be determined experimentally from thin standards (3) or calculated (4,6). Both experimental and calculated k12 values have been obtained for K(11<Z>19),kα(Z>19) and some Lα radiation (3,6) at 100 kV. The object of the present series of experiments was to experimentally determine k12 values at voltages between 200 and 1000 kV and to compare these with calculated values.The experiments were carried out on an AEI-EM7 HVEM fitted with an energy dispersive X-ray detector.

SIGMAL: A Program for Calculating L-Shell lonization Cross-Sections

1981 ◽  
Vol 39 ◽  
pp. 198-199 ◽  
Author(s):  
R.F. Egerton
Keyword(s):  
Cross Sections ◽  
Fortran Program ◽  
Absorption Data ◽  
X Ray ◽  
Atomic Electrons ◽  
Energy Dependent ◽  
Hydrogenic Model ◽  
Electron Energy Loss ◽  
X Ray Absorption ◽  
Shell Ionization

SIGMAL is a short (∼ 100-line) Fortran program designed to rapidly compute cross-sections for L-shell ionization, particularly the partial crosssections required in quantitative electron energy-loss microanalysis. The program is based on a hydrogenic model, the L1 and L23 subshells being represented by scaled Coulombic wave functions, which allows the generalized oscillator strength (GOS) to be expressed analytically. In this basic form, the model predicts too large a cross-section at energies near to the ionization edge (see Fig. 1), due mainly to the fact that the screening effect of the atomic electrons is assumed constant over the L-shell region. This can be remedied by applying an energy-dependent correction to the GOS or to the effective nuclear charge, resulting in much closer agreement with experimental X-ray absorption data and with more sophisticated calculations (see Fig. 1 ).

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