Wyniki wyszukiwania - BazTech

1

Effect of electron beam injection on boron redistribution in silicon and oxide layer

Qin S., Tan Y., Li J., Jiang D., Wen S., Shi S.

Materials Science Poland

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2017

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Vol. 35, No. 1

14--17

EN

The behavior of boron redistribution in silicon with and without oxide layer after electron beam injection (EBI) was investigated. Special defect shapes were generated on the surface of bare and oxidized silicon wafers. Secondary ion mass spectrometer was used to measure the boron profile. The results showed that after long EBI time, boron tended to be induced from both sides of the transition region between the oxide layer and silicon. For the sample without oxide layer after EBI, boron tended to diffuse towards the surface and its concentration obviously reduced inside the silicon. The results of the study show the potential use of the process in removing boron impurity in silicon.

2

Phase, microstructure and microwave dielectric properties of A-site deficient (La, Nd) 2/3TiO3 perovskite ceramics

Saleem M., Iqbal Y., Qin S., Wu X., Zhu F.

Materials Science Poland

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2015

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Vol. 33, No. 1

126--130

EN

(La, Nd)2/3TiO3 ceramics were prepared through a conventional solid state mixed oxide route. For phase and microstructure analysis, XRD and SEM were used, respectively. Microwave dielectric properties were measured using a network analyzer. XRD patterns revealed the formation of the parent (La, Nd)2/3TiO3 phase along with (La, Nd)4Ti9O24 as a secondary phase. The microstructure consisted of rectangular and needle shaped grains, which decreased in size from 4 μ m to 2 μm with an increase in sintering temperature from 1300 °C to 1350 °C. Decrease in grain size caused an increase in density of the samples from 4.81 g/cm3 to 5.17 g/cm3. Microwave dielectric properties of the samples calcined and sintered in air atmosphere were εr = 40.35, Q × f = 3499 GHz and τ f = 0 ppm/°C, whereas for a sample calcined in nitrogen and sintered in air they were εr = 40.18, Q × f = 4077 GHz and τ f = +4.9 ppm/°C, respectively.

3

Analysis of Wind Stability of Cable-stayed Bridge with Single Cable Plane

Wang H., Qin S., Tan Y.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 9b

22-24

EN

Taking Lanqi SongHua River Bridge as an example, this paper has made an analysis of the dynamic character, wind-resistant stability and flutter instability are analyzed, especially the analysis of the flutter stability at maximum double cantilever stage during construction phase. This paper analyzes the dynamic characters of the FE model of the whole bridge through response spectrum method to reap the natural frequency, the vibration modes and other parameters, and then checks the flutter stability. The results show that the bridge is very safe. The analysis method provides bases and references for the wind-resistant of Lanqi SongHua River Bridge.

PL

W artykule zaprezentowano wykorzystanie metody element skończonego do analizy właściwości dynamicznych mostu wiszącego na rzece Langi SongHua. Analizowano stabilność drgań, naturalną częstotliwość drań, wibracje odporność na porywy wiatru.

4

On pinching theorems for compact pseudo-umbilical submanifold

Mao J., Qin S.

Demonstratio Mathematica

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2012

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Vol. 45, nr 3

645-654

EN

Consider submanifolds in the nested space. For a compact pseudoumbilical submanifold with parallel mean curvature vector of a Riemannian submanifold with constant curvature immersed in a quasi-constant curvature Riemannian manifold, two sufficient conditions are given to let the pseudo-umbilical submanifold become a totally umbilical submanifold.

5

Crystallization of TeO2-Nb2O5 glasses and their network structural evolution

Lin J., Huang W., Ma L., Bian Q., Qin S., Wei H., Chen J.

Materials Science Poland

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2009

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Vol. 27, No. 1

329--338

EN

TeO2-Nb2O5 glass is a kind of heavy metal oxide glass with a chain-like network structure, in which Nb5+ ions connect the Te-O chains and adjust the types of [TeOx] (x = 3, 4) coordination polyhedra to stabilize the glass network. (100 - y)TeO2-yNb2O5 (y = 3-20 mol %) glasses were prepared, the crystallization behaviour and their network structural evolution were studied by means of differential thermal analysis (DTA), X-ray diffraction (XRD) and Fourier transform infrared spectra (FT-IR). The results show that the stabilization of the TeO2-Nb2O5 glass network is greatly influenced by the constitution of Te-O chains and their linkage. The glass structure with lower Nb5+ content is inhomogeneous, it is composed of edge sharing Te-O chains, partly edge sharing chains connected by Nb5+ ions, apical sharing chains and apical sharing chains connected by Nb5+ ions. Crystalline phases of ß-TeO2, Nb2Te4O13, .beta.-TeO2 and Te3Nb2O11 will be formed in turn when the treatment temperature of the glass is increased. When the concentration of Nb5+ ions is sufficient to well connect Te-O chains, the glass network will tend to homogenize, only one crystalline phase, Nb2Te4O13, will be formed. A suitable preheat treatment will also help to homogenize the glass structure and make the glass more stable.