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1.
A set of a-SiOx:H (0.52 <x< 1.58) films are fabricated by plasma-enhanced-chemical-vapor-deposition (PECVD) method at the substrate temperature of 250°C. The microstructure and local bonding configurations of the films are investigated in detail using micro-Raman scattering, X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). It is found that the films are structural inhomogeneous, with five phases of Si, Si2O:H, SiO:H, Si2O3:H and SiO2 that coexist. The phase of Si is composed of nonhydrogenated amorphous silicon (a-Si) clusters that are spatially isolated. The average size of the clusters decreases with the increasing oxygen concentration x in the films. The results indicate that the structure of the present films can be described by a multi-shell model, which suggests that a-Si cluster is surrounded in turn by the subshells of Si2O:H, SiO:H, Si2O3:H, and SiO2.  相似文献   

2.
A set of a-SiOx:H (0.52 <x< 1.58) films are fabricated by plasma-enhanced-chemical-vapor-deposition (PECVD) method at the substrate temperature of 250°C. The microstructure and local bonding configurations of the films are investigated in detail using micro-Raman scattering, X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). It is found that the films are structural inhomogeneous, with five phases of Si, Si2O:H, SiO:H, Si2O3:H and SiO2 that coexist. The phase of Si is composed of nonhydrogenated amorphous silicon (a-Si) clusters that are spatially isolated. The average size of the clusters decreases with the increasing oxygen concentration x in the films. The results indicate that the structure of the present films can be described by a multi-shell model, which suggests that a-Si cluster is surrounded in turn by the subshells of Si2O:H, SiO:H, Si2O3:H, and SiO2.  相似文献   

3.
Two strong photoluminescence (PL) bands in the spectral range of 550–900 nm have been observed at room temperature from a series of a-SiO x :H films fabricated by plasma-enhanced chemical vapor deposition (PECVD) technique. One is composed of a main band in the red-light region and a shoulder; the other is located at about 850 nm, only found after 1170°C annealing in N2 atmosphere. In conjunction with infrared (IR) and micro-Raman spectra, it is thought that the two PL bands are associated with a-Si clusters in the SiO x network and nanocrystalline silicon in SiO2, respectively. Project supported by the National Natural Science Foundation of China (Grant No. 69576025).  相似文献   

4.
本文研究了不可压磁流体方程组弱解的正则性准则,设(u(t,x),6(t,x))是不可压磁流体方程组在(O,T)上的光滑解,如果旋度和电流密度满足(▽× u,▽× b) ∈ L 2-a/2 (O, T;B-aa∞, ∞(R3)) ηL1-a/2(O,T;B-∞1,-a∞(R3)),0<α<1,则光滑解(u(t,x),b(t,x))可以连续延拓到(O,T'),T'>T.而且这个条件可以保证满足能量不等式的弱解是(O,T)上的光滑解.  相似文献   

5.
正规六边形和更广泛具有正规结构的Banach 空间   总被引:1,自引:1,他引:0  
高继 《数学杂志》2000,20(3):241-248
假设X是一个实Banach空间,S(X)是单位球面。作者引进了一个新的几何参数(H(X),讨论了H(X)和Neumann-Jordan常数CNJ(X)R 性质以及H(X)和其他几何常数的关系,本文主要结果是:H(X)〈2或CNJ(X)〈4/5一致正规结构。  相似文献   

6.
C3N4 films have been synthesized on both Si and Pt substrates by microwave plasma chemical vapor deposition (MPCVD) method. X-ray spectra were calculated for single phase α-C3N4 and β-C3N4 respectively. The experimental X-ray spectra of films deposited on both Si and Pt substrates showed all the strong peaks of α-C3N4 and β-C3N4, so the films are mixtures of α-C3N4 and β-C3N4. The N/C atomic ratio is in the range of 1.0-2.0. X-ray photoelectron spectroscopy (XPS) analysis indicated that the binding energy of C 1s and N 1s are 286.2 eV and 399.5 eV respectively, corresponding to polarized C-N bond. Fourier transform infrared absorption (FT-IR) and Raman spectra support the existence of C-N covalent bond in the films. Nano-indentation hardness tests showed that the bulk modulus of a film deposited on Pt is up to 349 GPa.  相似文献   

7.
Motivated by Schur-concavity, we introduce the notion of G -concavity where G is a closed subgroup of the orthogonal group O ( V ) on a finite dimensional real inner product space V . The triple ( V , G , F ) is an Eaton triple if F ² V is a nonempty closed convex cone such that (A1) Gx 7 F is nonempty for each x ε V . (A2) max g ε G ( x,gy ) = ( x,gy ) for all x, y ε F . If W := span F and H := { g | W : g ε G , gW = W } ² O ( W ), and ( W , H , F ) is an Eaton triple, then ( W , H , F ) is called a reduced triple of the Eaton triple ( V , G , F ). In this event, a characterization of the G -concavity in terms of H -concavity is obtained. Some differential characterizations of G -concavity are then given. The results are applied to Lie groups. Various matrix examples are given.  相似文献   

8.
设H是一实Hillber空间,K是H之一非空间凸子集,设{Ti}Ni=1是N个Lipschitz伪压缩映象使得F=∩Ni=1F(Ti)≠0,其中F(Ti)={x∈K:Tix=x}并且{αn}n∞=1,{βn}∞n=1[0,1]是满足如下条件的实序列(i)∑∞n=1(1-αn)2= ∞;(ii)limn→∞(1-αn)=0;(iii)∑∞n=1(1-βn)< ∞;(iv)(1-αn)L2<1,n1;(v)αn(1-βn)2 αn[βn L(1-βn)]2<1,其中L1是{Ti}iN=1的公共Lipschitz常数,对于x0∈K,设{xn}n∞=1是由下列定义的复合隐格式迭代xn=αnxn-1 (1-αn)Tnyn,yn=βnxn (1-βn)Tnxn,其中Tn=TnmodN,则(i)limn→∞‖xn-p‖存在,对于所有的p∈F;(ii)limn→∞d(xn,f)存在,其中d(xn,F)=infp∈F‖xn-p‖;(iii)liminfn→∞‖xn-Tnxn‖=0.本文的结果推广并且改进H-K.Xu和R.G.Ori在2001年的结果和Osilike在2004年的结果,并且在这篇文章中,主要的证明方法也不同与H-K.Xu和Osilike的方法.  相似文献   

9.
In this paper, it was proved that the commutator Hβ,b generated by an n-dimensional fractional Hardy operator and a locally integrable function b is bounded from Lp1(Rn) to Lp2 (Rn) if and only if b is a C(M)O(Rn) function, where 1/p1 - 1/p2 = β/n, 1 < p1 <∞, 0 ≤β< n. Furthemore,the characterization of Hβ,b on the homogenous Herz space (K)qα,p(Rn) was obtained.  相似文献   

10.
黄正中 《数学学报》1956,6(3):452-463
<正> 1952年P.Hartman和A.Wintner建立了下述定理:設連續函數E(u,ν),F(u,ν),G(u,ν)在點(0,0)的鄰域內满足條件  相似文献   

11.
谢晖春 《数学学报》1959,9(3):281-291
<正> 关于奈望利纳(Nevanlinna)氏第二基本不等式曾有引入纪(导)数而作之种种不同的推广,在这些推广式中,极点的密指量每见出现且有特殊作用,因之能否将此量消去是一问题.米约(Milloux)氏及熊庆来教授由不同途径各获得与极点无涉之一不等式此二结果形状互异而各有特点.熊庆来教授指出这两个结果尚可推广到更普遍的境地,我们由此方向探研得如下两个定理,为熊、米二氏者之推广.  相似文献   

12.
C3N4 films have been synthesized on both Si and Ft substrates by microwave plasma chemical vapor deposition (MPCVD) method. X-ray spectra were calculated for single phase α-C3N4 and β-C3N4 respectively. The experimental X-ray spectra of films deposited on both Si and Pt substrates showed all the strong peaks of α-C3N4 and β-C3N4 so the films are mixtures of α-C3N4 and β-C3N4. The N/C atomic ratio is in the range of 1.0–2.0. X-ray photoelectron spectroscopy (XPS) analysis indicated that the binding energy of Is and N ls are 286.2 eV and 399.5 eV respectively, corresponding to polarized C-N bond. Fourier transform infrared absorption (FT-IR) and Raman spectra support the existence of C-N covalent bond in the films. Nano-indentation hardness tests showed that the bulk modulus of a film deposited on Pt is up to 349 GPa  相似文献   

13.
Microtwins in the 3C-SiC films grown on Si(001) by APCVD were analyzed in detail using an X-ray four-circle diffractometer. The Φ scan shows that 3C-SiC films can grow on Si substrates epitaxially and the epitaxial relationship is revealed as (001)3C-SiC//(001)Si,[111]3C-SiC//[111]Si. Other diffractions emerged in the pole figures of the (111) 3C-SiC. We performed the (1010)h-SiC and the reciprocal space mapping of the (002) plane of twins for the first time, finding that the diffractions at χ=15.8° result from not hexagonal SiC but microtwins of 3C-SiC, and twin inclusions are estimated to be 1%.  相似文献   

14.
关于图中子图的(n,k)—正交因子分解   总被引:1,自引:0,他引:1  
李建湘 《数学研究》2001,34(4):339-344
设G是一个具有顶点集V(G)和边集E(G)的图. 设g和f是定义在V(G)上的两个整数值函数,使得g(x)f(x)对所有的点x∈V(G)都成立.如果G是一个(mg+n,mf-n)-图,1n<m2k,且g(x)2k-1对所有的点x∈V(G)都成立,则对任意给定具有|E(H)|=nk边的G的子图H,存在G的一个子图G′使G′有一个(g,f)-因子分解(n,k)-正交H.  相似文献   

15.
心理状态数的Bayes估计   总被引:4,自引:0,他引:4  
设误差 X在心理状态数的作用下的分布为偏正态分布 ,即 X有密度f ( x;σ2 ,C) =C2πσe-x22σ2   x 02 - C2πσe-x22σ2   x >0其中 0 C 2为心理状态数 ,σ>0为未知参数 ,本文分别在 C服从 [C1,C2 ]上的均匀分布 ,Jeffreys无信息先验分布和共轭先验分布的假设下 ,得到了心理状态数 C的 Bayes估计。  相似文献   

16.
假设E为一致凸的Banach空间,对偶空间E*有Kadec-Klee性质,K为E的非空闭凸子集{Ti:i=1,2,…,N}:K→K为Browder-Petryshyn意义下的严格伪压缩映像且F=∩Ni=1F(Ti)≠0.{αn}n∞=1满足0相似文献   

17.
秦元勳 《数学学报》1960,10(1):125-142
<正> §1.問題的提出及解法 錢学森在[1]中提出了有时滞的系統的无条件稳定性的問題,并叙述了Satche的作图法.对于有时滞的系統的稳定性問題,一般化为超越方程的根的实部的符号的判定問題,这方面有及,Hayes及Bellman等人的工  相似文献   

18.
李建湘 《经济数学》2002,19(3):19-23
设G是一个n阶图.设1≤a<b是整数.设H1和H2是G的任意两个边不交子图,它们分别具有m1和m5条边,以及δ(G)表示最小度.证明了若δ(G)≥a+m 2,n≥2(d+b-m2)(a+b-m1-1)/(b-m1),a≤b-(m1+m2),并且|NG(x)UNG(y)|≥an/(d+b-m1)+2m2对任意两个不相邻的顶点x和y成立,那么G有[a,b]-因子F使得F含有H1的边并不含H3的边.  相似文献   

19.
给出了最佳参数α_1,α_2,α_3,β_1,β_2,β_3∈R,使得双向不等式α_1Q(a,b)+(1-α_1)G(a,b)0且a≠b成立.其中A(a,b)=(a+b)/2,H(a,b)=2ab/(a+b),G(a,b)=(ab)~(1/2),Q(a,b)=((a~2+b~2)/2)~(1/2),C(a,b)=(a~2+b~2)/(a+b),T(a,b)=2/π∫_0~(π/2)(a~2cos~2t+b~2sin~2)~(1/2)tdt分别是两个正数a和b的算术平均,调和平均,几何平均,二次平均,反调和平均和Toader平均.  相似文献   

20.
董光昌 《数学学报》1956,6(2):242-249
<正>考虑下列混合型议程的唯一性问题 K(y)u_(xx)+u_(yy)=0 (K(0)=0;当y≠0时,■(1) 所考慮的區域D由三條曲綾圍成.其一是雙曲區域(y<0)中由原點引出的特徵线Γ_1,它滿足下面條件  相似文献   

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