关于Saitō猜想

Hakeda在[1]中研究了c-代数中Jordan映射的可加性,设M和N为AW-代数,M→N被称为Jordan-映射,如果满足下述条件: (3)为双射,其中,x·y=1/2(xy yx).     

非混沌的树映射

设f是树T上的连续自映射,SAP(f),ω(f);Ω(f)分别是f的强几乎周期点集,ω-极限集,非游荡集.本文证明下面几条是等价的:(i)f是非混沌的;(ii)SAP(f)=ω(f);(iii)fΩ(f)是逐点等度连续的;(iv)f│ω(f)是逐点等度连续的;(v)f是一致非混沌的。     

图映射的吸引中心与拓扑熵

设f是图G上的连续自映射，P(f)，AГ(f)，ω(f)，Ω(f)，sα(y，f)分别表示f的周期点集，单侧γ-极限点集，ω-极限集，非游荡集，相对于y的特殊α-极限点集．本文证明了：(1)x∈sα(y，f)(对某个y∈G)当且仅当x∈sα(x，f)(2)AГ(f)∪P(f)包含∪y∈Gsα(y，f)(3)AГ(f)∪P(f)=ω(Ω(f))=ω(ω(f))=ω(∪y∈Gsα(y,f))=ω(∪（AГ(f)∪P(f))．此外，本文还得到了，具有正拓扑熵的几个等价条件。     

从一道习题谈起

<正> 在参考资料(1)中有这样一个命题(见(1)P129习题8),“若函数项级数sum from n=1 to ∞u_n(x)在区间〔a,b〕上收敛于函数S(x),而且所有u_n(x)都是〔a,b〕上的非负连续函数,则函数S(x)必     

2,6—二甲酸吡啶氮氧化物与稀土硝酸盐配合物的合成及表征

在无水乙醇介质中合成了２，６－二甲酸吡啶氮氧化物（Ｈ２ＰｄＣＯ）和稀土硝酸盐形成的配合物［ＲＥ（ＰｄＣＯ）·ＮＯ３·２Ｈ２Ｏ］（ＲＥ＝Ｌａ－Ｎａ，Ｓｍ，Ｅｕ，Ｔｂ，Ｈｏ，Ｅｒ，Ｙ）。通过元素分析，摩尔电导，红外光谱，紫外光谱，１Ｈ核磁共振谱及热重－差热分析等对该系列配合物进行了表征，并研究了Ｅｕ（Ⅲ），Ｔｂ（Ⅲ）配合物荧光性质。     

Effect of additional silicon on titanium/4H-SiC contacts properties

The Ti electrode was deposited on the(0001) face of an n-type 4H-SiC substrate by magnetron sputtering. The effect of the electrode placement method during the annealing treatment on the contact property was carefully investigated. When the electrode was faced to the Si tray and annealed, it showed ohmic behavior, otherwise it showed a non-ohmic property.X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS), scanning electron microscopy(SEM), and atomic force microscopy(AFM) were used to characterize the electrode phase, composition, thickness, and surface morphology. The additional silicon introduced from the Si tray played a key role in the formation of the ohmic contact on the Ti/4H-SiC contact.     

CRYSTALLINE CARBON NITRIDE THIN FILMS DEPOSITED BY MICROWAVE PLASMA CHEMICAL VAPOR DEPOSITION

The crystalline carbon nitride thin films have been prepared on Si (100) substrates using microwave plasma chemical vapor deposition technique. The experimental X-ray diffraction pattern of the films prepared contain all the strong peaks of α-C₃N₄ and β-C₃N₄, but most of the peaks are overlapped.The films are composed of α-C₃N₄ and β-C₃N₄. The N/C atomic ratio is close to the stoichiometric value 1.33. X-ray photoelectron spectroscopic analysis indicated that the binding energies of C 1s and N 1s are 286.43eV and 399.08 eV respectively. The shifts are attributed to the polarization of C-N bond. Both observed Raman and Fourier transform infrared spectra were compared with the theoretical calculations. The results support the existence of C-N covalent bond in α- and β-C₃N₄ mixture.     

微波等离子体化学气相沉积法制备C3N4薄膜的结构研究

采用微波等离子体化学气相沉积法,用高纯氮气(99.999%)和甲烷(99.9%)作反应气体,在单晶Si(100)基片上沉积C₃N₄薄膜.利用扫描电子显微镜观察薄膜形貌,表明薄膜由密排的六棱晶棒组成.X射线衍射和透射电子显微镜结构分析说明该薄膜主要由β-C₃N₄和α-C₃N₄组成,并且这些结果与α-C₃N₄相符合较好.由虎克定律近似关 关键词： 3N₄')" href="#">C₃N₄ 微波等离子体化学气相沉积法 薄膜沉积     

激光触发能量对横向结构4H-SiC光导开关导通电阻的影响

采用钒掺杂半绝缘4H-SiC衬底,利用磁控溅射在硅衬底上制备了Ni/Au金属电极,并封装加工成同面型横向电极结构SiC光导开关,研究了不同激光触发能量对光导开关光电响应及导通电阻的影响。用波长532nm的激光作为触发源,当激光触发能量从26.7mJ增加到43.9mJ时,光导开关的导通电阻从295Ω降低到197Ω。利用复合理论推导出激光触发时导带中载流子浓度随时间的变化规律,并利用MATLAB模拟计算了不同触发能量下开关的导通电阻,得到了与实验较一致的结果。在此基础上,提出了降低开关导通电阻的两种途径。     

SUPERSYMMETRIC INVARIANCE AND UNIVERSAL CENTRAL EXTENSIONS OF LIE SUPERTRIPLE SYSTEMS

In this article, we discuss some properties of a supersymmetric invariant bilinear form on Lie supertriple systems. In particular, a supersymmetric invariant bilinear form on Lie supertriple systems can be extended to its standard imbedding Lie superalgebras. Furthermore, we generalize Garland＇s theory of universal central extensions for Lie supertriple systems following the classical one for Lie superalgebras. We solve the problems of lifting automorphisms and lifting derivations.