Vibrational Studies of Ultra-Thin Oxides and Initial Silicon Oxidation

Author(s):  
Y. J. Chabal ◽  
M. K. Weldon ◽  
K. T. Queeney ◽  
A. Estève
2002 ◽  
Vol 66 (16) ◽  
Author(s):  
Y. J. Chabal ◽  
Krishnan Raghavachari ◽  
X. Zhang ◽  
E. Garfunkel

2020 ◽  
Vol 7 (2) ◽  
pp. 21-28
Author(s):  
SALI RADZHAPOV ◽  
◽  
RUSTAM RAKHIMOV ◽  
BEGJAN RADZHAPOV ◽  
MARS ZUFAROV

The article describes the developed radiometer for Express measurement of alpha radiation of radioactive elements based on a large-diameter silicon detector. The main element of the PPD detector is made using computer mathematical modeling of all stages of the technological process of manufacturing detectors, taking into account at each stage the degree of influence of the properties of the initial silicon on the electrophysical and radiometric characteristics of the detector. Detectors are manufactured for certain types of devices. The developed radiometer is designed to measure alpha radiation of natural isotopes (238U, 234U, 232Th, 226Ra, 222Rn, 218Po, 214Bi, etc.) in various environments. It also shows the principle of operation of the device, provides a block diagram of the measuring complex, describes the electronic components of the radiometer, as well as the block diagram. Signal transformations (spectrum transfer, filtering, accumulation) are implemented programmatically on the basis of a digital processing module. The device can detect the presence of specific elements in various environments, as well as protect people from the harmful effects of adverse radiation and can be used both in the field and stationary.


2019 ◽  
Author(s):  
Evan Gardner ◽  
Caitlyn Cobb ◽  
Jeffery A. Bertke ◽  
Timothy H. Warren

A modular synthesis provides access to a series of new tris(pyrazolyl)borate ligands <sup>XpyMe</sup>TpK that possess a single functionalized pendant pyridyl (py) or pyrimidyl (pyd) arm designed to engage in tunable intramolecular H-bonding to metal–bound functionalities. To illustrate such H-bonding interactions, a series of [<sup>XpyMe</sup>TpCu]<sub>2</sub>(𝜇–OH)<sub>2</sub>(<b>6a</b><b>–6e</b>) complexes were synthesized from the corresponding <sup>XpyMe</sup>TpCu–OAc (<b>5a–5e</b>) complexes. Single crystal X-ray structures of three new dinuclear [<sup>XpyMe</sup>TpCu]<sub>2</sub>(𝜇–OH)<sub>2</sub>complexes reveal H-bonding between the pendant heterocycle and bridging hydroxide ligands while the donor arm engages the copper center in an unusual monomeric <sup>DMAPMe</sup>TpCu–OH complex. Vibrational studies (IR) of each bridging hydroxide complex reveal reduced 𝜈<sub>OH </sub>frequencies that tracks with the H-bond accepting ability of the pendant arm.


2019 ◽  
Author(s):  
Evan Gardner ◽  
Caitlyn Cobb ◽  
Jeffery A. Bertke ◽  
Timothy H. Warren

A modular synthesis provides access to a series of new tris(pyrazolyl)borate ligands <sup>XpyMe</sup>TpK that possess a single functionalized pendant pyridyl (py) or pyrimidyl (pyd) arm designed to engage in tunable intramolecular H-bonding to metal–bound functionalities. To illustrate such H-bonding interactions, a series of [<sup>XpyMe</sup>TpCu]<sub>2</sub>(𝜇–OH)<sub>2</sub>(<b>6a</b><b>–6e</b>) complexes were synthesized from the corresponding <sup>XpyMe</sup>TpCu–OAc (<b>5a–5e</b>) complexes. Single crystal X-ray structures of three new dinuclear [<sup>XpyMe</sup>TpCu]<sub>2</sub>(𝜇–OH)<sub>2</sub>complexes reveal H-bonding between the pendant heterocycle and bridging hydroxide ligands while the donor arm engages the copper center in an unusual monomeric <sup>DMAPMe</sup>TpCu–OH complex. Vibrational studies (IR) of each bridging hydroxide complex reveal reduced 𝜈<sub>OH </sub>frequencies that tracks with the H-bond accepting ability of the pendant arm.


2020 ◽  
Vol 59 (SM) ◽  
pp. SM0801
Author(s):  
Shuichi Ogawa ◽  
Akitaka Yoshigoe ◽  
Jaiyi Tang ◽  
Yuki Sekihata ◽  
Yuji Takakuwa
Keyword(s):  

2005 ◽  
Vol 61 (a1) ◽  
pp. c79-c80 ◽  
Author(s):  
F. Datchi ◽  
S. Ninet ◽  
M. Gauthier ◽  
A. M. Saitta

2009 ◽  
Vol 2009 ◽  
pp. 1-4 ◽  
Author(s):  
L. Bourja ◽  
B. Bakiz ◽  
A. Benlhachemi ◽  
M. Ezahri ◽  
J. C. Valmalette ◽  
...  

A series of ceramics samples belonging to theCeO2-Bi2O3phase system have been prepared via a coprecipitation route. The crystallized phases were obtained by heating the solid precursors at600∘Cfor 6 hours, then quenching the samples. X-ray diffraction analyses show that forx<0.20a solid solutionCe1−xBixO2−x/2with fluorine structure is formed. For x ranging between 0.25 and 0.7, a tetragonalβ′phase coexisting with the FCC solid solution is observed. For x ranging between 0.8 and 0.9, a new tetragonalβphase appears. Theβ′phase is postulated to be a superstructure of theβphase. Finally, close tox=1, the classical monoclinicα Bi2O3structure is observed. Raman spectroscopy confirms the existence of the phase changes as x varies between 0 and 1.


2009 ◽  
Vol 40 (9) ◽  
pp. 1150-1157 ◽  
Author(s):  
J. Santos Coelho ◽  
W. Paraguassu ◽  
M. Maczka ◽  
A. G. Souza Filho ◽  
P.T.C. Freire ◽  
...  

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