scholarly journals Optical Properties of In Situ Eye Lenses Measured with X-Ray Talbot Interferometry: A Novel Measure of Growth Processes

PLoS ONE ◽  
2011 ◽  
Vol 6 (9) ◽  
pp. e25140 ◽  
Author(s):  
Masato Hoshino ◽  
Kentaro Uesugi ◽  
Naoto Yagi ◽  
Satoshi Mohri ◽  
Justyn Regini ◽  
...  
Author(s):  
Mette Ø. Filsø ◽  
Iman Chaaban ◽  
Amer Al Shehabi ◽  
Jørgen Skibsted ◽  
Nina Lock

Two different two-dimensional thiostannates (SnS) were synthesized using tris(2-aminoethyl)amine (tren) or 1-(2-aminoethyl)piperidine (1AEP) as structure-directing agents. Both structures consist of negatively charged thiostannate layers with charge stabilizing cations sandwiched in-between. The fundamental building units are Sn3S4broken-cube clusters connected by double sulfur bridges to form polymeric (Sn3S72−)nhoneycomb hexagonal layers. The compounds are members of theR-SnS-1 family of structures, whereRindicates the type of cation. Despite consisting of identical structural units, the band gaps of the two semiconducting compounds were found to differ substantially at 2.96 eV (violet–blue light) and 3.21 eV (UV light) for tren–SnS-1 and 1AEP–SnS-1, respectively. Aiming to explain the observed differences in optical properties, the structures of the two thiostannates were investigated in detail based on combined X-ray diffraction, solid-state13C and119Sn MAS NMR spectroscopy and scanning electron microscopy studies. The compound tren–SnS-1 has a hexagonal structure consisting of planar SnS layers with regular hexagonal pores and disordered cations, whereas 1AEP–SnS-1 has an orthorhombic unit cell with ordered cations, distorted hexagonal pores and non-planar SnS layers. In the formation of 1AEP–SnS-1, an intramolecular reaction of the structure-directing piperidine takes place to form anN-heterobicyclic cation throughin situC—H activation. Hirshfeld surface analysis was used to investigate the interaction between the SnS layers and cations in 1AEP–SnS-1 and revealed that the most nucleophilic part of the SnS sheets is one of the two crystallographically distinct double sulfur bridges.


2005 ◽  
Vol 86 (9) ◽  
pp. 092501 ◽  
Author(s):  
W. Li ◽  
X. H. Li ◽  
H. Y. Sun ◽  
J. W. Zhang ◽  
X. Y. Zhang

2003 ◽  
Vol 81 (1-2) ◽  
pp. 479-484 ◽  
Author(s):  
S Takeya ◽  
Y Kamata ◽  
T Uchida ◽  
J Nagao ◽  
T Ebinuma ◽  
...  

X-ray diffraction measurements were conducted to determine the hydrate structures formed from a mixture of CH4 and C2H6 gases at 263 K. With increasing initial fractions of C2H6 in the gas, the crystal structures of the hydrate were structure I, structure I + structure II, structure II, structure I + structure II, and structure I. In situ observations of the growth processes of the mixed gas hydrates under constant gas concentration suggest that the coexistence of structure I and structure II hydrate were caused by occurrences of metastable hydrate structure. PACS No.: 82.75Fq


NANO ◽  
2015 ◽  
Vol 10 (02) ◽  
pp. 1550021 ◽  
Author(s):  
Zhankui Cui ◽  
Senlin Li ◽  
Junqiang Zhou ◽  
Jianli Zhang ◽  
Suxiang Ge ◽  
...  

Spherical Bi 2 S 3 nanoparticles (NPs) were prepared by a facile in situ thermal sulfuration method. Different Bi 2 S 3 samples were obtained by controlling the sulfuration time. The products were characterized by X-ray diffractometer (XRD), scanning electron microscopy (SEM), Raman and Fourier-transform infrared (FT-IR) methods. The optical properties were examined by UV-visible-near-infrared (UV-Vis–NIR) and photoluminescence (PL) techniques. The results show that the phase of the products after sulfuration is pure and the spherical shape of Bi NPs has been successfully transmitted to Bi 2 S 3 samples. The light absorption edges exhibit red shift to 1060 nm while the light emission displays blue shift to 868 nm, compared with the energy bandgap of bulk Bi 2 S 3. The reason for the special optical properties of Bi 2 S 3 NPs by this in situ sulfuration route is considered to associate with the defects and quantum size effect of NPs.


Author(s):  
R. E. Herfert

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.


1997 ◽  
Vol 7 (C2) ◽  
pp. C2-619-C2-620 ◽  
Author(s):  
M. Giorgett ◽  
I. Ascone ◽  
M. Berrettoni ◽  
S. Zamponi ◽  
R. Marassi

2016 ◽  
Vol 12 (3) ◽  
pp. 4394-4399
Author(s):  
Sura Ali Noaman ◽  
Rashid Owaid Kadhim ◽  
Saleem Azara Hussain

Tin Oxide and Indium doped Tin Oxide (SnO2:In) thin films were deposited on glass and Silicon  substrates  by  thermal evaporation technique.  X-ray diffraction pattern of  pure SnO2 and SnO2:In thin films annealed at 650oC and the results showed  that the structure have tetragonal phase with preferred orientation in (110) plane. AFM studies showed an inhibition of grain growth with increase in indium concentration. SEM studies of pure  SnO2 and  Indium doped tin oxide (SnO2:In) ) thin films showed that the films with regular distribution of particles and they have spherical shape.  Optical properties such as  Transmission , optical band-gap have been measured and calculated.


2019 ◽  
Author(s):  
Christian Prehal ◽  
Aleksej Samojlov ◽  
Manfred Nachtnebel ◽  
Manfred Kriechbaum ◽  
Heinz Amenitsch ◽  
...  

<b>Here we use in situ small and wide angle X-ray scattering to elucidate unexpected mechanistic insights of the O2 reduction mechanism in Li-O2 batteries.<br></b>


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