scholarly journals Влияние водорода на импеданс структур Pd/оксид/InP

Author(s):  
В.А. Шутаев ◽  
Е.А. Гребенщикова ◽  
В.Г. Сидоров ◽  
М.Е. Компан ◽  
Ю.П. Яковлев

The impedance and capacitance properties of Pd/oxide/InP structures within the frequency range from 0.1 Hz to 10 kHz in air and in gaseous hydrogen–nitrogen mixture at 300 K have been studied. The characteristics of investigated structures can be characterized by parallel RC circuit model with the connected serial resistance. In hydrogen medium the active resistance of the structures decreases by 3 orders of magnitude and the capacitance increases by 1–3 orders of magnitude depending on frequency that is due probably to the positive charged centers formed in the oxide layer. In hydrogen medium the hysteresis has been found on CV-characteristics of the structures that may be explained by ion polarization of formed centers. It is shown that measured in electron units the full charge of the centers practically coincides with the quantity of hydrogen atoms absorbed by palladium.

2013 ◽  
Vol 33 (1) ◽  
pp. 0117001
Author(s):  
李小霞 Li Xiaoxia ◽  
何俊 He Jun ◽  
韩雪梅 Han Xuemei

1996 ◽  
Vol 109 (2) ◽  
pp. 159-163 ◽  
Author(s):  
Jae-Min Hong ◽  
Yong Soo Kang ◽  
Jyongsik Jang ◽  
Un Young Kim

Metamaterials ◽  
2009 ◽  
Vol 3 (2) ◽  
pp. 57-62 ◽  
Author(s):  
V. Delgado ◽  
O. Sydoruk ◽  
E. Tatartschuk ◽  
R. Marqués ◽  
M.J. Freire ◽  
...  

Author(s):  
T. Takeyama ◽  
H. Takahashi

It is considered that hydrogen atoms in iron dissolve interstitially in the matrix, segregate at some lattice defects, are absorbed at the interface of foreign atoms or inclusion, and/or precipitate as a gas phase. This precipitation of gaseous hydrogen in iron causes the formation of void, microcrack and blister, which affects the mechanical properties of the iron. Fracture due to hydrogen embrittlement may be caused by a crack initiation and growth, and propagation. It is obvious that this fracture depends on the diffusion of hydrogen atoms through the iron. However, the mechanism of hydrogen embrittlement cracking has not been fully explained.The aim of the present work was to investigate the microcrack and microvoid generated by the precipitation of hydrogen charged by cathodic method.Pure iron was cold-rolled to a sheet of 0.5mm thickness. After cutting, specimens were annealed at 700°C for one hour in a vacuum of 10-5torr. The grain size was l0̴20 μm. The specimens were charged with hydrogen by applying cathodic potentials in electrolytic cells containing O.1N-H2SO4 with the addition of 250 mg/ℓsodium arsenite to act as a recombination poison.


2016 ◽  
Vol 2016 (1) ◽  
pp. 000288-000292
Author(s):  
Timothy Clingenpeel ◽  
Arian Rahimi ◽  
Seahee Hwangbo ◽  
Yong-Kyu Yoon ◽  
Aric Shorey

Abstract This work presents the fabrication process, electrical characteristics, and circuit model of through glass via (TGV) structures consisting of TGV holes with each diameter of 100 μm and different conductors including copper and composite in the frequency range of 300 kHz to 20 GHz. The Cu/NiFe superlattice metaconductors in combination with high-quality glass (Corning SGW3) are intended to reduce radio-frequency losses especially in 10 GHz and above for next generation communication applications such as 5G communications. The measured results of the copper structure are compared to simulated results. Superlattice metaconductor results will be presented. Based on the simulation and measurement results, a circuit model is demonstrated.


Author(s):  
Karel Mozdřeň ◽  
Eduard Sojka ◽  
Radovan Fusek ◽  
Milan Šurkala

1996 ◽  
Vol 109 (2) ◽  
pp. 149-157 ◽  
Author(s):  
Yong Soo Kang ◽  
Jae-Min Hong ◽  
Jyongsik Jang ◽  
Un Young Kim

It has been shown that ethynyl radicals may be satisfactorily generated by the photolysis, at 253.7 nm, of bromoacetylene in the presence of nitric oxide. Acetylene and butadiyne are primary products, being formed exclusively by the reactions C 2 H . + C 2 HBr→C 2 H 2 + C 2 Br . , C 2 H . + C 2 HBr→C 4 H 2 + Br . . Nitric oxide decreases the rates of formation of both products, indicating the effective scavenging of ethynyl radicals by this compound. Addition of an inert gas (nitrogen or carbon dioxide) increases the ratio [C 4 H 2 ]/[C 2 H 2 ] from 3.5 (no inert gas) to 7 (total pressure 80 kPa (1 Pa = 1 N m -2 )), the ratio thereafter remaining constant. The most obvious explanation for this behaviour is that, during photolysis, ethynyl radicals produced in the absence of inert gas have excess translational energy and, probably, enhanced reactivity. With increasing inert gas pressure, fewer ‘hot’ radicals react and the change in the ratio [C 4 H 2 ]/[C 2 H 2 ] reflects the change in selectivity of ‘thermalized’ ethynyl radicals. On account of this, investigations of the reactions of C 2 H . with added hydrocarbons were carried out with a standard 1:1:100 bromoacetylene-nitric oxide-nitrogen mixture. Results obtained with added alkanes (methane, ethane, 2,2 dimethylpropane) showed that ethynyl radicals abstract hydrogen atoms to form acetylene: C 2 H . + RH→C 2 H 2 + R . , The relative importance of reactions (1) and (2) has been estimated and values for k 1 / k 2 of 0.016 ± 0.005, 0.54 ± 0.04 and 0 .91 ± 0.04 have been obtained for methane, and ethane 2,2-dimethylpropane respectively. The ratio k 1 / k 2 did not vary over the temperature range 298 to 478 K in the case of 2,2-dimethylpropane but with methane, values for E 1 — E 2 and A 2 / A 1 of 12.54 ± 1.27 kJ mol -1 and 0.54 ± 0.25, respectively, were obtained. Studies of the reactions of ethynyl radicals with alkynes (acetylene, butadiyne and propyne) have shown that the radicals abstract hydrogen atoms (to form acetylene), displace hydrogen atoms (to form a di- or triyne) and, in the case of propyne, displace a methyl radical. For propyne, the relevant reactions are C 2 H . + C 3 H 4 →C 2 H 2 + C 3 H 3 . , C 2 H . + C 3 H 4 →C 4 H 2 + CH 3 . , C 2 H . + C 3 H 4 →C 5 H 4 + H . , and Values of 25 ± 3, 5 ± 2, 9.9 ± 1 and 23 ± 3 at 298 K have been obtained for k 7 / k 9 , k 4 / k 9 , k 8 / k 9 and k 2 / k 9 respectively. In the presence of butadiyne, acetylene and hexatriyne are formed as primary products. Acetylene is formed by reactions (4) and (13), C 2 H . +C 4 H 2 → C 2 H 2 + C 4 H . , whilst hexatriyne is formed by the displacement reaction (14) C 2 H . + C 4 H 2 →C 6 H 2 +H . . Kinetic measurements have shown that at 298 K k 4 / k 14 =0.6 ± 0.1 and k 13 / k 14 = 1.1 ± 0.2. Addition of acetylene-d 2 to bromoacetylene-nitrogen mixtures yields acetylene-d 1 and butadiyne-d 1 C 2 H . + C 2 D 2 → C 2 HD +C 2 D . , C 2 H . + C 2 D 2 → C 4 HD + D . . The rate-constant ratios k 12 / k 11 and k 2 / k 12 are 2 .8 ± 2.5 and 1.5 ± 0.3 respectively. This work thus indicates that ethynyl radical addition-elimination reactions, leading to polyalkynes, occur to a comparable extent to hydrogen-abstraction reactions in acetylene-containing systems. These results are shown to be of significance in regard to the formation and subsequent reactions of polyalkynes in both the pyrolysis and flames of acetylene and other hydrocarbons.


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