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1.
Well-cubic perovskite lanthanum aluminate (LaAlO3) film on (110) silicon substrate was fabricated by sol-gel method with corresponding inorganic salts. Lanthanum acetate and
aluminum acetate glacial acetic acid solutions were prepared via ligand exchange starting from lanthanum nitrate hexahydrate
and aluminum nitrate hexahydrate after being refluxed. (CH3CO)2O removed nitrates and the crystallized H2O completely, acetylacetone (AcAc) was partially bidentated with metallic ion of the metallic acetates and formed La(OAc)3−x
(AcAc)
x
which were hydrolyzed into La(AcAc)3−x(OH)
x
by adding 10 ml 0.4% methyl cellulose (MCL) solution. The La(AcAc)3−x
(OH)
x
, polymerizing and combining with MCL, formed the LaAlO3 sol precursor with heteropolymeric structure and formed film easily. The epitaxial LaAlO3 film on Si(110) substrate was crystallized after being annealed in thermal annealing furnace for 650–750 °C/30 min. The morphologies
and microstructures were characterized. The refractive index of the LAO film was 1.942 to 2.007; the dielectric constant and
the dissipation factors were estimated to be 23–26 and 2.1×10−4−2.4×10−4 respectively.
Project (No. 2002CB613305) supported by the National Basic Research Program (973) of China 相似文献
2.
Aditya Mahabhai Vora 《上海大学学报(英文版)》2008,12(4):311-317
A well-known pseudopotential is used to investigate the superconducting state parameters (SSP), viz., electronphonon coupling strength, Coulomb pseudopotential, transition temperature, isotope effect exponent and effective
interaction strength for Ag
x
Zn1 − x
and Ag
x
Al1 − x
binary alloys theoretically for the first time. We have incorporated here five different types of the local field correction
functions to show the effect of exchange and correlation on the aforesaid properties. Very strong influence of various exchange
and correlation functions is concluded from the present study. Comparison with others such experimental values is encouraging,
which confirms applicability of the model potential in explaining the superconducting state parameters of binary mixture.
相似文献
3.
JIANG Xiao-yuan DU Feng ZHANG Xu JIA Yan-rong ZHENG Xiao-ming 《浙江大学学报(A卷英文版)》2007,8(11):1839-1845
Using SnxTi1-xO2 as carriers, CuO/Sn0.9Ti0.1O2 and CuO/Sn0.7Ti0.3O2 catalysts with different loading amounts of copper oxide (CuO) were prepared by an impregnation method. The catalytic properties of CuO/Sn0.9Ti0.1O2 and CuO/Sn0.7Ti0.3O2 were examined using a microreactor-gas chromatography (GC) NO CO reaction system and the methods of BET (Brun- auer-Emmett-Teller), TG-DTA (themogravimetric and differential thermal analysis), X-ray diffraction (XRD) and H2-temperature programmed reduction (TPR). The results showed that NO conversions of Sn0.9Ti0.1O2 and Sn0.7Ti0.3O2 were 47.2% and 43.6% respectively, which increased to 95.3% and 90.9% at 6 wt% CuO loading. However, further increase in CuO loading caused a decrease in the catalytic activity. The nitrogen adsorption-desorption isotherm and pore-size distribution curve of Sn0.9Ti0.1O2 and Sn0.7Ti0.3O2 represented type IV of the BDDT (Brunauer, Deming, Deming and Teller) system and a typical mesoporous sample. There were two CuO diffraction peaks (2θ 35.5° and 38.7°), and the diffraction peak areas increased with increasing CuO loading. TPR analysis also detected three peaks (α, β and γ) from the CuO-loaded catalysts, suggesting that the α peak was the reduction of the highly dispersed copper oxide, the β peak was the reduction of the isolated copper oxide, and the γ peak was the reduction of crystal phase copper oxide. In addition, a fourth peak (δ) of the catalysts meant that the SnxTi1-xO2 mixed oxides could be reductive. 相似文献
4.
MBE growth of ZnSxSe1−x thin films on ITO coated glass substrates were carried out using ZnS and Se sources with the substrate temperature ranging
from 270°C to 330°C. The XRD σ/2σ spectra resulted from these films indicated that the as-grown polycrystalline ZnSxSe1−x thin films had a preferred orientation along the (111) planes. The evaluated crystal sizes as deduced from the FWHM of the
XRD layer peaks showed strong growth temperature dependence, with the optimized temperature being about 290 °C. Both AFM and
TEM measurements of these thin films also indicated a similar growth temperature dependence. High quality ZnSxSe1−x thin film grown at the optimized temperature had the smoothest surface with lowest RMS value of 1.2 nm and TEM cross-sectional
micrograph showing a well defined columnar structure.
Project supported by the National Science Council of PRC (No. 59910161981) and RGC grant from the Hong Kong Government under
Grant (No. NS-FC/HKUST 35) 相似文献
5.
6.
The construction of multirate rearrangeable network has long been an interesting problem. Of many results published, all were
achieved on 3-stage Clos network. The monotone routing algorithm proposed by Huet al. (2001) was also first applied to 3-stage Clos network. In this work, we adopt this algorithm and apply it to log
d
(N,m,p) networks. We first analyze the properties of log
d
(N,m,p) networks. Then we use monotone algorithm in log
d
(N,0,p) network. Furthermore we extend the result to construct multirate rearrangeable networks based on log
d
(N,m,p) network (1≤m≤n−1).
Project (No. 10371028) supported by the National Natural Science Foundation of China 相似文献
7.
LetH
n
be the set of real algebraic polynomials of degreen, whose zeros all lie in the interval [−1,1]. The well known Turán type inequalities tell us that forf(x)∈H
n
, it holds ‖f′‖≥C√n‖f‖. This note deals with the weighted Turán type inequalities with the weights having inner singularities underL
p
norm for 0<p≤∞. Our results essentially extend the result of Wang and Zhou (2002), and the method used in this paper is simpler and more
direct than that of Wang and Zhou (2002). The results and methods have their own values in approximation theory and computation. 相似文献
8.
Xi-qiang Li 《上海大学学报(英文版)》2000,4(2):163-166
Single crystal Ga
x
In1−x
As films have grown up on GaAs(100) substrate at 375°C and on InP(100) substrate at 390°C, respectively, by the method of
rf-sputtering with using undoped GalnAs polycrystal as target. However, on Si(100) or Si(111) substrates at 260–390°C, even
at 465°C, only polycrystalline films were obtained. In addition, the structure, composition, electrical characteristic and
optical properties of the Ga
x
In1−x
As films were investigated using X-ray diffraction (XRD), reflection of high energy electron diffraction (RHEED), energy dispersion
analyzer of X-ray (EDAX), Hall measurements and spectroscopic ellipsometry. 相似文献
9.
10.
Well-cubic perovskite lanthanum aluminate (LaAlO3) film on (110) silicon substrate was fabricated by sol-gel method with corresponding inorganic salts. Lanthanum acetate and aluminum acetate glacial acetic acid solutions were prepared via ligand exchange starting from lanthanum nitrate hexahydrate and aluminum nitrate hexahydrate after being refluxed. (CH3CO)2O removed nitrates and the crystallized H2O completely, acetylacetone (AcAc) was partially bidentated with metallic ion of the metallic acetates and formed La(OAc)3(x(AcAc)x, which were hydrolyzed into La(AcAc)3(x(OH)x by adding 10 ml 0.4% methyl cellulose (MCL) solution. The La(AcAc)3(x(OH)x, polymerizing and combining with MCL, formed the LaAlO3 sol precursor with heteropolymeric structure and formed film easily. The epitaxial LaAlO3 film on Si(110) substrate was crystallized after being annealed in thermal annealing furnace for 650(750 (C/30 min. The morphologies and microstructures were characterized. The refractive index of the LAO film was 1.942 to 2.007; the dielectric constant and the dissipation factors were estimated to be 23(26 and 2.1(10(4 ( 2.4(10(4 respectively. 相似文献
11.
Supersaturated solid solutions Fe1-xCx (0≤x≤0.9 ) of wide composition range have been prepared by mechanical alloying process. Nanocrystalline phase was formed for 0 ≤ x ≤ 0.67 and a large grain phase for 0.75 ≤ x ≤ 0.9. The large fraction of graphite volume puts off formation of nanocrystalline phase for high carbon content. In the large grain phase, magnetization follows simple magnetic dilution, and eoereivity He is mainly due to dissolution of carbon at grain boundaries. In the nanocrystalline phase the alloying effect of carbon is revealed by a distinct reduction of average magnetic moment. The increasing lattice constant with increasing carbon content is observed for x ≤ 0.5, suggesting that the high carbon concentration may enhance diffusion of carbon into the Fe lattice. It shows a discontinuity in the Hc variation with a grain size D of nanocrystalline phase. For small grain D below the critical value, Hc increases with D. For a large grain D, Hc decreases with increasing D. The solubility limit of carbon in a-Fe extended by nanocry- stalline phase formation is discussed. 相似文献
12.
A novel nano-TiO2-xNx composite was used as photocatalyst and added to the interior wall paint. The average diameter of nano-TiO2-xNx was about 20 nm. The majority crystal component of the sample was anatase and its optical absorption edge was shifted from 387 nm to 520 nm significantly. Nano-composite paint containing different dosage of nano- TiO2-xNx was investigated to study the properties of formaldehyde decomposition in the air. Testing results show that the formaldehyde decomposition ratio of that nano-paint can almost reach above 80%, especially for that of the paint containing 3% (w/w) nano-TiO2-xNx which exceeded 90%. The primary investigation on the reaction kinetics of photocatalytic formaldehyde decomposition indicated that the experiment data well fit the model of first-order reaction kinetics. 相似文献
13.
14.
Xian-jin Yu Ph. D. Guang-li Zhang Zhu-xian Qiu Min-shou Zhao Qiang Su 《上海大学学报(英文版)》1999,3(3):251-254
ZnFe2O4 and ZnFe2O4-based materials were tested to obtain the electrical conductivity and corrosion resistance in melting bath for aluminum electrolysis.
The results proved that adequate additives, such as Ni2O3 CuO, Cu, ZnO and CeO2 would increase the electrical conductivity, and the ZnFe2O4-based anodes with these additives were of good corrosion resistance. The current density on anode, the mole ratio of NaF/AlF3 (MR) and the content of alumina in the bath effect the anode corrosion rate in different way.
Project supported by the Science Foundation of Liaoning Province, P. R. China (95 – 156) 相似文献
15.
Scrubbing of NO
x
from the gas phase with Fe(II)EDTA has been shown to be highly effective. A new biological method can be used to convert
NO to N2 and regenerate the chelating agent Fe(II)EDTA for continuous NO absorption. The core of this biological regeneration is how
to effectively simultaneous reduce Fe(III)EDTA and Fe(II)EDTA-NO, two mainly products in the ferrous chelate absorption solution.
The biological reduction rate of Fe(III)EDTA plays a main role for the NO
x
removal efficiency. In this paper, a bacterial strain identified asKlebsiella Trevisan sp. was used to demonstrate an inhibition of Fe(III)EDTA reduction in the presence of Fe(II)EDTA-NO. The competitive inhibition
experiments indicted that Fe(II)EDTA-NO inhibited not only the growth rate of the iron-reduction bacterial strain but also
the Fe(III)EDTA reduction rate. Cell growth rate and Fe(III)EDTA reduction rate decreased with increasing Fe(II)EDTA-NO concentration
in the solution.
Project (No. 20176052) supported by the National Natural Science Foundation of China and the Scientific Research Foundation
for Returned Overseas Chinese Scholars, Ministry of Education 相似文献
16.
This paper proposes a new approach for multi-objective robust control. The approach extends the standard generalizedl
2 (Gl
2) and generalizedH
2 (GH
2) conditions to a set of new linear matrix inequality (LMI) constraints based on a new stability condition. A technique for
variable parameterization is introduced to the multi-objective control problem to preserve the linearity of the synthesis
variables. Consequently, the multi-channel multi-objective mixed Gl
2/GH
2 control problem can be solved less conservatively using computationally tractable algorithms developed in the paper.
Project supported by the National Natural Science Foundation of China (No. 60374028), and the Scientific Research Foundation
for Returned Overseas Chinese Scholars, Ministry of Education (No. [2004]176) 相似文献
17.
In this paper, the Tφ-convex functions were introduced as a generalizations of convex functions. Then the characteristics of the Tφ-convex functions were discussed. Furthermore, some new inequalities for the Tφ-convex functions were derived. 相似文献
18.
19.
SO4^2- / TiO2-La2O3, a novel solid superacid, was prepared and its catalytic activities at different synthetic conditions are discussed with esterification of n-butanoic acid and n-butyl alcohol as probing reaction. The optimum conditions have also been found, mole ratio of n(La^3+):n(Ti^4+) is 1:34, the soaked consistency of H2SO4 is 0.8 tool/L, the soaked time of HESO4 is 24 h, the calcining temperature is 480 ℃, the calcining time is 3 h. Then it was applied in the catalytic synthesis often important ketals and acetals as catalyst and revealed high catalytic activity. Under these conditions on which the molar ratio of aldehyde/ketone to glycol is l: 1.5, the mass ratio of the catalyst used in the reactants is 0.5%, and the reaction time is 1.0 h, the yields of ketals and acetals can reach 41.4%-95.8%. 相似文献
20.
1 Introduction Ahugeamountofliteratureexistsonthestudyofi dentifyingtracemetalionsbymeansofspectropho tometry[1 3] ,fluorimetry[4 6 ] aswellas polarogra phy[7 9] ,whichhaveactiononlocatingtheendpointoftheindicatingreaction .Howeverbothspectropho tometryandfluorimetryareeasytobeinterferedbycolororprecipitation ,whilepolarographyhasanissueofmercurypollution .Thecatalyzingkineticanalysishasthecharacteristicsofhighsensitivityandspeedi ness.Oscillographicpotentiometryisasimpleintu itionisticanal… 相似文献