Elastic-Recoil-Detection Measurement of Instabilities in Proton-Exchanged Lithium Niobate

1987 ◽  
Vol 101 ◽  
Author(s):  
G. W. Arnold ◽  
A. Carnera ◽  
G. Mazzi ◽  
P. Mazzoldi
Keyword(s):  
Crystal Orientation ◽  
Annealing Temperature ◽  
Exchange Process ◽  
Proton Exchange ◽  
Elastic Recoil ◽  
Elastic Recoil Detection ◽  
Simultaneous Measurements ◽  
Acid Proton ◽  
Proton Source ◽  
Orientation Time

ABSTRACTThe H and Li profiles in proton-exchanged (PE) LiNbO3, have been measured using elastic recoil detection (ERD). Profiles were determined as a function of crystal orientation, time after PE, annealing temperature, MgO-doping, and added Li-benzoate to the benzoic acid proton source. The proton-exchange process produces Hx Li1−x NbO3 structures where x stabilizes near values of x=0.5 or x=0.7-0.75 depending on specific conditions. The ERD measurements represent the first direct and simultaneous measurements of H- and Li-concentrations in PE LiNbO3 and their variation with process parameters.

Yttrium Oxyhydrides for Photochromic Applications: Correlating Composition and Optical Response

2018 ◽  
Author(s):  
Dmitrii Moldarev ◽  
Elbruz M. Baba ◽  
Marcos V. Moro ◽  
Chang C. You ◽  
Smagul Zh. Karazhanov ◽  
...  
Keyword(s):  
Medical Devices ◽  
Ternary Diagram ◽  
Optical And Electrical Properties ◽  
Ambient Conditions ◽  
Elastic Recoil ◽  
Elastic Recoil Detection Analysis ◽  
Photochromic Properties ◽  
Smart Windows ◽  
Elastic Recoil Detection ◽  
Detection Analysis

It has been recently demonstrated that yttrium oxyhydride(YHO) films can exhibit reversible photochromic properties when exposed to illumination at ambient conditions. This switchable optical propertyenables their utilization in many technological applications, such as smart windows, sensors, goggles, medical devices, etc. However, how the composition of the films affects their optical properties is not fully clear and therefore demands a straightforward investigation. In this work, the composition of YHO films manufactured by reactive magnetron sputtering under different conditions is deduced in a ternary diagram from Time-of-Flight Elastic Recoil Detection Analysis (ToF-ERDA). The results suggest that stable compounds are formed with a specificchemical formula – YH<sub>2-δ</sub>O<sub>δ</sub>. In addition, optical and electrical properties of the films are investigated, and a correlation with their compositions is established. The corresponding photochromic response is found in a specific oxygen concentration range (0.45 < δ < 1.5) with maximum and minimum of magnitude on the lower and higher border, respectively.

Study of the rapid thermal nitridation and silicidation of Ti using elastic recoil detection. I. Ti on Si

1988 ◽  
Vol 63 (10) ◽  
pp. 5104-5109 ◽  
Author(s):  
G. J. P. Krooshof ◽  
F. H. P. M. Habraken ◽  
W. F. van der Weg ◽  
L. Van den hove ◽  
K. Maex ◽  
...  
Keyword(s):  
Elastic Recoil ◽  
Elastic Recoil Detection ◽  
Thermal Nitridation

scholarly journals Phosphate-Catalyzed Succinimide Formation from an NGR-Containing Cyclic Peptide: A Novel Mechanism for Deammoniation of the Tetrahedral Intermediate

Molecules ◽  
2018 ◽  
Vol 23 (9) ◽  
pp. 2217 ◽  
Author(s):  
Ryota Kirikoshi ◽  
Noriyoshi Manabe ◽  
Ohgi Takahashi
Keyword(s):  
Conformational Changes ◽  
Density Functional ◽  
Cyclic Peptide ◽  
Density Functional Theory Method ◽  
Proton Exchange ◽  
Computational Method ◽  
Side Chain ◽  
Tetrahedral Intermediate ◽  
Rate Determining Step ◽  
Proton Source

Spontaneous deamidation in the Asn-Gly-Arg (NGR) motif that yields an isoAsp-Gly-Arg (isoDGR) sequence has recently attracted considerable attention because of the possibility of application to dual tumor targeting. It is well known that Asn deamidation reactions in peptide chains occur via the five-membered ring succinimide intermediate. Recently, we computationally showed by the B3LYP density functional theory method, that inorganic phosphate and the Arg side chain can catalyze the NGR deamidation using a cyclic peptide, c[CH2CO–NGRC]–NH2. In this previous study, the tetrahedral intermediate of the succinimide formation was assumed to be readily protonated at the nitrogen originating from the Asn side chain by the solvent water before the release of an NH3 molecule. In the present study, we found a new mechanism for the decomposition of the tetrahedral intermediate that does not require the protonation by an external proton source. The computational method is the same as in the previous study. In the new mechanism, the release of an NH3 molecule occurs after a proton exchange between the peptide and the phosphate and conformational changes. The rate-determining step of the overall reaction course is the previously reported first step, i.e., the cyclization to form the tetrahedral intermediate.

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